Heat and Drought Stresses in Crops and Approaches for Their Mitigation.

PubMed

Lamaoui, Mouna; Jemo, Martin; Datla, Raju; Bekkaoui, Faouzi

2018-01-01

Drought and heat are major abiotic stresses that reduce crop productivity and weaken global food security, especially given the current and growing impacts of climate change and increases in the occurrence and severity of both stress factors. Plants have developed dynamic responses at the morphological, physiological and biochemical levels allowing them to escape and/or adapt to unfavorable environmental conditions. Nevertheless, even the mildest heat and drought stress negatively affects crop yield. Further, several independent studies have shown that increased temperature and drought can reduce crop yields by as much as 50%. Response to stress is complex and involves several factors including signaling, transcription factors, hormones, and secondary metabolites. The reproductive phase of development, leading to the grain production is shown to be more sensitive to heat stress in several crops. Advances coming from biotechnology including progress in genomics and information technology may mitigate the detrimental effects of heat and drought through the use of agronomic management practices and the development of crop varieties with increased productivity under stress. This review presents recent progress in key areas relevant to plant drought and heat tolerance. Furthermore, an overview and implications of physiological, biochemical and genetic aspects in the context of heat and drought are presented. Potential strategies to improve crop productivity are discussed.

Crop development related to temperature and photoperiod in temperate cereals

USDA-ARS?s Scientific Manuscript database

Plant development, or the progression of plants through their life cycle, has been of great interest in human history because of the need to know and predict when the harvested part of the plant was at the optimum stage. This knowledge was especially important (even vital) in medicinal plants, where...

Comparative Infection Progress Analysis of Lettuce big-vein virus and Mirafiori lettuce virus in Lettuce Crops by Developed Molecular Diagnosis Techniques.

PubMed

Navarro, Jose A; Botella, Francisco; Maruhenda, Antonio; Sastre, Pedro; Sánchez-Pina, M Amelia; Pallas, Vicente

2004-05-01

ABSTRACT Nonisotopic molecular dot blot hybridization technique and multiplex reverse transcription-polymerase chain reaction assay for the specific detection of Lettuce big-vein virus (LBVV) and Mirafiori lettuce virus (MiLV) in lettuce tissue were developed. Both procedures were suitable for the specific detection of both viruses in a range of naturally infected lettuce plants from various Spanish production areas and seven different cultivars. The study of the distribution of both viruses in the plant revealed that the highest concentration of LBVV and MiLV occurred in roots and old leaves, respectively. LBVV infection progress in a lettuce production area was faster than that observed for MiLV. In spite of different rates of virus infection progress, most lettuce plants became infected with both viruses about 100 days posttransplant. The appearance of both viruses in lettuce crops was preceded by a peak in the concentration of resting spores and zoosporangia of the fungus vector Olpidium brassicae in lettuce roots.

Not all GMOs are crop plants: non-plant GMO applications in agriculture.

PubMed

Hokanson, K E; Dawson, W O; Handler, A M; Schetelig, M F; St Leger, R J

2014-12-01

Since tools of modern biotechnology have become available, the most commonly applied and often discussed genetically modified organisms are genetically modified crop plants, although genetic engineering is also being used successfully in organisms other than plants, including bacteria, fungi, insects, and viruses. Many of these organisms, as with crop plants, are being engineered for applications in agriculture, to control plant insect pests or diseases. This paper reviews the genetically modified non-plant organisms that have been the subject of permit approvals for environmental release by the United States Department of Agriculture/Animal and Plant Health Inspection Service since the US began regulating genetically modified organisms. This is an indication of the breadth and progress of research in the area of non-plant genetically modified organisms. This review includes three examples of promising research on non-plant genetically modified organisms for application in agriculture: (1) insects for insect pest control using improved vector systems; (2) fungal pathogens of insects to control insect pests; and (3) virus for use as transient-expression vectors for disease control in plants.

Effects of selenium biofortification on crop nutritional quality.

PubMed

Malagoli, Mario; Schiavon, Michela; dall'Acqua, Stefano; Pilon-Smits, Elizabeth A H

2015-01-01

Selenium (Se) at very low doses has crucial functions in humans and animals. Since plants represent the main dietary source of this element, Se-containing crops may be used as a means to deliver Se to consumers (biofortification). Several strategies have been exploited to increase plant Se content. Selenium assimilation in plants affects both sulfur (S) and nitrogen (N) metabolic pathways, which is why recent research has also focused on the effect of Se fertilization on the production of S- and N- secondary metabolites with putative health benefits. In this review we discuss the function of Se in plant and human nutrition and the progress in the genetic engineering of Se metabolism to increase the levels and bioavailability of this element in food crops. Particular attention is paid to Se biofortification and the synthesis of compounds with beneficial effects on health.

Two facets of world arsenic problem solution: crop poisoning restriction and enforcement of phytoremediation.

PubMed

Kofroňová, Monika; Mašková, Petra; Lipavská, Helena

2018-05-07

This review provides insights into As toxicity in plants with focus on photosynthesis and sugar metabolism as important arsenic targets and simultaneously defence tools against accompanying oxidative stress. Heavy metal contamination is a great problem all over the world. Arsenic, a metalloid occurring naturally in the Earth's crust, also massively spreads out in the environment by human activities. Its accumulation in crops poses a severe health risk to humans and animals. Besides the restriction of human-caused contamination, there are two basic ways how to cope with the problem: first, to limit arsenic accumulation in harvestable parts of the crops; second, to make use of some arsenic hyperaccumulating plants for phytoremediation of contaminated soils and waters. Progress in the use of both strategies depends strongly on the level of our knowledge on the physiological and morphological processes resulting from arsenic exposure. Arsenic uptake is mediated preferentially by P and Si transporters and its accumulation substantially impairs plant metabolism at numerous levels including damages through oxidative stress. Rice is a predominantly studied crop where substantial progress has been made in understanding of the mechanisms of arsenic uptake, distribution, and detoxification, though many questions still remain. Full exploitation of plant potential for soil and water phytoremediations also requires deep understanding of the plant response to this toxic metalloid. The aim of this review is to summarize data regarding the effect of arsenic on plant physiology with a focus on mechanisms providing increased arsenic tolerance and/or hyperaccumulation. The emphasis is placed on the topic unjustifiably neglected in the previous reviews - i.e., carbohydrate metabolism, tightly connected to photosynthesis, and beside others involved in plant ability to cope with arsenic-induced oxidative and nitrosative stresses.

[Plant physiological and molecular biological mechanism in response to aluminium toxicity].

PubMed

Liu, Qiang; Zheng, Shaojian; Lin, Xianyong

2004-09-01

Aluminium toxicity is the major factor limiting crop growth on acid soils, which greatly affects the crop productivity on about 40% cultivated soils of the world and 21% of China. In the past decades, a lot of researches on aluminium toxicity and resistant mechanisms have been doing, and great progress was achieved. This paper dealt with the genetic differences in aluminium tolerance among plants, screening and selecting methods and technologies for identifying aluminium resistance in plants, and physiological and molecular mechanism resistance to aluminium toxicity. Some aspects needed to be further studied were also briefly discussed.

Challenges towards Revitalizing Hemp: A Multifaceted Crop.

PubMed

Schluttenhofer, Craig; Yuan, Ling

2017-11-01

Hemp has been an important crop throughout human history for food, fiber, and medicine. Despite significant progress made by the international research community, the basic biology of hemp plants remains insufficiently understood. Clear objectives are needed to guide future research. As a semi-domesticated plant, hemp has many desirable traits that require improvement, including eliminating seed shattering, enhancing the quantity and quality of stem fiber, and increasing the accumulation of phytocannabinoids. Methods to manipulate the sex of hemp plants will also be important for optimizing yields of seed, fiber, and cannabinoids. Currently, research into trait improvement is hindered by the lack of molecular techniques adapted to hemp. Here we review how addressing these limitations will help advance our knowledge of plant biology and enable us to fully domesticate and maximize the agronomic potential of this promising crop. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Dynamic Succession of Soil Bacterial Community during Continuous Cropping of Peanut (Arachis hypogaea L.)

PubMed Central

Chen, Mingna; Li, Xiao; Yang, Qingli; Chi, Xiaoyuan; Pan, Lijuan; Chen, Na; Yang, Zhen; Wang, Tong; Wang, Mian; Yu, Shanlin

2014-01-01

Plant health and soil fertility are affected by plant–microbial interactions in soils. Peanut is an important oil crop worldwide and shows considerable adaptability, but growth and yield are negatively affected by continuous cropping. In this study, 16S rRNA gene clone library analyses were used to study the succession of soil bacterial communities under continuous peanut cultivation. Six libraries were constructed for peanut over three continuous cropping cycles and during its seedling and pod-maturing growth stages. Cluster analyses indicated that soil bacterial assemblages obtained from the same peanut cropping cycle were similar, regardless of growth period. The diversity of bacterial sequences identified in each growth stage library of the three peanut cropping cycles was high and these sequences were affiliated with 21 bacterial groups. Eight phyla: Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Planctomycetes, Proteobacteria and Verrucomicrobia were dominant. The related bacterial phylotypes dynamic changed during continuous cropping progress of peanut. This study demonstrated that the bacterial populations especially the beneficial populations were positively selected. The simplification of the beneficial microbial communities such as the phylotypes of Alteromonadales, Burkholderiales, Flavobacteriales, Pseudomonadales, Rhizobiales and Rhodospirillales could be important factors contributing to the decline in peanut yield under continuous cropping. The microbial phylotypes that did not successively changed with continuous cropping, such as populations related to Rhizobiales and Rhodospirillales, could potentially resist stress due to continuous cropping and deserve attention. In addition, some phylotypes, such as Acidobacteriales, Chromatiales and Gemmatimonadales, showed a contrary tendency, their abundance or diversity increased with continuous peanut cropping progress. Some bacterial phylotypes including Acidobacteriales, Burkholderiales, Bdellovibrionales, and so on, also were affected by plant age. PMID:25010658

Plant salt-tolerance mechanisms

DOE PAGES

Deinlein, Ulrich; Stephan, Aaron B.; Horie, Tomoaki; ...

2014-06-01

Crop performance is severely affected by high salt concentrations in soils. To engineer more salt-tolerant plants it is crucial to unravel the key components of the plant salt-tolerance network. Here we review our understanding of the core salt-tolerance mechanisms in plants. Recent studies have shown that stress sensing and signaling components can play important roles in regulating the plant salinity stress response. We also review key Na+ transport and detoxification pathways and the impact of epigenetic chromatin modifications on salinity tolerance. In addition, we discuss the progress that has been made towards engineering salt tolerance in crops, including marker-assisted selectionmore » and gene stacking techniques. We also identify key open questions that remain to be addressed in the future.« less

Genetically modified (GM) crops: milestones and new advances in crop improvement.

PubMed

Kamthan, Ayushi; Chaudhuri, Abira; Kamthan, Mohan; Datta, Asis

2016-09-01

New advances in crop genetic engineering can significantly pace up the development of genetically improved varieties with enhanced yield, nutrition and tolerance to biotic and abiotic stresses. Genetically modified (GM) crops can act as powerful complement to the crops produced by laborious and time consuming conventional breeding methods to meet the worldwide demand for quality foods. GM crops can help fight malnutrition due to enhanced yield, nutritional quality and increased resistance to various biotic and abiotic stresses. However, several biosafety issues and public concerns are associated with cultivation of GM crops developed by transgenesis, i.e., introduction of genes from distantly related organism. To meet these concerns, researchers have developed alternative concepts of cisgenesis and intragenesis which involve transformation of plants with genetic material derived from the species itself or from closely related species capable of sexual hybridization, respectively. Recombinase technology aimed at site-specific integration of transgene can help to overcome limitations of traditional genetic engineering methods based on random integration of multiple copy of transgene into plant genome leading to gene silencing and unpredictable expression pattern. Besides, recently developed technology of genome editing using engineered nucleases, permit the modification or mutation of genes of interest without involving foreign DNA, and as a result, plants developed with this technology might be considered as non-transgenic genetically altered plants. This would open the doors for the development and commercialization of transgenic plants with superior phenotypes even in countries where GM crops are poorly accepted. This review is an attempt to summarize various past achievements of GM technology in crop improvement, recent progress and new advances in the field to develop improved varieties aimed for better consumer acceptance.

Biotechnology and synthetic biology approaches for metabolic engineering of bioenergy crops.

PubMed

Shih, Patrick M; Liang, Yan; Loqué, Dominique

2016-07-01

The Green Revolution has fuelled an exponential growth in human population since the mid-20th century. Due to population growth, food and energy demands will soon surpass supply capabilities. To overcome these impending problems, significant improvements in genetic engineering will be needed to complement breeding efforts in order to accelerate the improvement of agronomical traits. The new field of plant synthetic biology has emerged in recent years and is expected to support rapid, precise, and robust engineering of plants. In this review, we present recent advances made in the field of plant synthetic biology, specifically in genome editing, transgene expression regulation, and bioenergy crop engineering, with a focus on traits related to lignocellulose, oil, and soluble sugars. Ultimately, progress and innovation in these fields may facilitate the development of beneficial traits in crop plants to meet society's bioenergy needs. © 2016 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

Elevating crop disease resistance with cloned genes

PubMed Central

Jones, Jonathan D. G.; Witek, Kamil; Verweij, Walter; Jupe, Florian; Cooke, David; Dorling, Stephen; Tomlinson, Laurence; Smoker, Matthew; Perkins, Sara; Foster, Simon

2014-01-01

Essentially all plant species exhibit heritable genetic variation for resistance to a variety of plant diseases caused by fungi, bacteria, oomycetes or viruses. Disease losses in crop monocultures are already significant, and would be greater but for applications of disease-controlling agrichemicals. For sustainable intensification of crop production, we argue that disease control should as far as possible be achieved using genetics rather than using costly recurrent chemical sprays. The latter imply CO2 emissions from diesel fuel and potential soil compaction from tractor journeys. Great progress has been made in the past 25 years in our understanding of the molecular basis of plant disease resistance mechanisms, and of how pathogens circumvent them. These insights can inform more sophisticated approaches to elevating disease resistance in crops that help us tip the evolutionary balance in favour of the crop and away from the pathogen. We illustrate this theme with an account of a genetically modified (GM) blight-resistant potato trial in Norwich, using the Rpi-vnt1.1 gene isolated from a wild relative of potato, Solanum venturii, and introduced by GM methods into the potato variety Desiree. PMID:24535396

Infection processes of xylem-colonizing pathogenic bacteria: possible explanations for the scarcity of qualitative disease resistance genes against them in crops.

PubMed

Bae, Chungyun; Han, Sang Wook; Song, Yu-Rim; Kim, Bo-Young; Lee, Hyung-Jin; Lee, Je-Min; Yeam, Inhwa; Heu, Sunggi; Oh, Chang-Sik

2015-07-01

Disease resistance against xylem-colonizing pathogenic bacteria in crops. Plant pathogenic bacteria cause destructive diseases in many commercially important crops. Among these bacteria, eight pathogens, Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, Erwinia amylovora, Pantoea stewartii subsp. stewartii, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. actinidiae, and Xylella fastidiosa, infect their host plants through different infection sites and paths and eventually colonize the xylem tissues of their host plants, resulting in wilting symptoms by blocking water flow or necrosis of xylem tissues. Noticeably, only a relatively small number of resistant cultivars in major crops against these vascular bacterial pathogens except X. oryzae pv. oryzae have been found or generated so far, although these pathogens threaten productivity of major crops. In this review, we summarize the lifestyles of major xylem-colonizing bacterial pathogens and then discuss the progress of current research on disease resistance controlled by qualitative disease resistance genes or quantitative trait loci against them. Finally, we propose infection processes of xylem-colonizing bacterial pathogens as one of possible reasons for why so few qualitative disease resistance genes against these pathogens have been developed or identified so far in crops.

RNAi-mediated resistance to viruses in genetically engineered plants.

PubMed

Ibrahim, Abdulrazak B; Aragão, Francisco J L

2015-01-01

RNA interference (RNAi) has emerged as a leading technology in designing genetically modified crops engineered to resist viral infection. The last decades have seen the development of a large number of crops whose inherent posttranscriptional gene silencing mechanism has been exploited to target essential viral genes through the production of dsRNA that triggers an endogenous RNA-induced silencing complex (RISC), leading to gene silencing in susceptible viruses conferring them with resistance even before the onset of infection. Selection and breeding events have allowed for establishing this highly important agronomic trait in diverse crops. With improved techniques and the availability of new data on genetic diversity among several viruses, significant progress is being made in engineering plants using RNAi with the release of a number of commercially available crops. Biosafety concerns with respect to consumption of RNAi crops, while relevant, have been addressed, given the fact that experimental evidence using miRNAs associated with the crops shows that they do not pose any health risk to humans and animals.

Natural genetic and induced plant resistance, as a control strategy to plant-parasitic nematodes alternative to pesticides.

PubMed

Molinari, Sergio

2011-03-01

Plant-parasitic nematodes are pests of a wide range of economically important crops, causing severe losses to agriculture. Natural genetic resistance of plants is expected to be a valid solution of the many problems nematodes cause all over the world. Progress in resistance applications is particularly important for the less-developed countries of tropical and subtropical regions, since use of resistant cultivars may be the only possible and economically feasible control strategy in those farming systems. Resistance is being considered of particular importance also in modern high-input production systems of developed countries, as the customary reliance on chemical nematicides has been restricted or has come to an end. This review briefly describes the genetic bases of resistance to nematodes in plants and focuses on the chances and problems of its exploitation as a key element in an integrated management program. Much space is dedicated to the major problem of resistance durability, in that the intensive use of resistant cultivars is likely to increasingly induce the selection of virulent populations able to "break" the resistance. Protocols of pest-host suitability are described, as bioassays are being used to evaluate local nematode populations in their potential to be selected on resistant germplasm and endanger resistant crops. The recent progress in using robust and durable resistances against nematodes as an efficient method for growers in vegetable cropping systems is reported, as well as the possible use of chemicals that do not show any unfavorable impact on environment, to induce in plants resistance against plant-parasitic nematodes.

The dynamics of hydroponic crops for simulation studies of the CELSS initial reference configurations

NASA Technical Reports Server (NTRS)

Volk, Tyler

1992-01-01

The goal of this research is to develop a progressive series of mathematical models for the CELSS hydroponic crops. These models will systematize the experimental findings from the crop researchers in the CELSS Program into a form useful to investigate system-level considerations, for example, dynamic studies of the CELSS Initial Reference Configurations. The crop models will organize data from different crops into a common modeling framework. This is the fifth semiannual report for this project. The following topics are discussed: (1) use of field crop models to explore phasic control of CELSS crops for optimizing yield; (2) seminar presented at Purdue CELSS NSCORT; and (3) paper submitted on analysis of bioprocessing of inedible plant materials.

Advances in molecular-based diagnostics in meeting crop biosecurity and phytosanitary issues.

PubMed

Schaad, Norman W; Frederick, Reid D; Shaw, Joe; Schneider, William L; Hickson, Robert; Petrillo, Michael D; Luster, Douglas G

2003-01-01

Awareness of crop biosecurity and phytosanitation has been heightened since 9/11 and the unresolved anthrax releases in October 2001. Crops are highly vulnerable to accidental or deliberate introductions of crop pathogens from outside U.S. borders. Strategic thinking about protection against deliberate or accidental release of a plant pathogen is an urgent priority. Rapid detection will be the key to success. This review summarizes recent progress in the development of rapid real-time PCR protocols and evaluates their effectiveness in a proposed nationwide network of diagnostic laboratories that will facilitate rapid diagnostics and improved communication.

Introduction to the Special Issue: Electrons, water and rice fields: plant response and adaptation to flooding and submergence stress

PubMed Central

Jackson, Michael B.; Ismail, Abdelbagi M.

2015-01-01

Flooding and submergence impose widespread and unpredictable environmental stresses on plants and depress the yield of most food crops. The problem is increasing, as is the need for greater food production from an expanding human population. The incompatibility of these opposing trends creates an urgent need to improve crop resilience to flooding in its multifarious forms. This Special Issue brings together research findings from diverse plant species to address the challenge of enhancing adaptation to flooding in major crops and learning from tactics of wetland plants. Here we provide an overview of the articles, with attempts to summarize how recent research results are being used to produce varieties of crop plants with greater flooding tolerance, notably in rice. The progress is considerable and based firmly on molecular and physiological research findings. The article also sets out how next-generation improvements in crop tolerance are likely to be achieved and highlights some of the new research that is guiding the development of improved varieties. The potential for non-model species from the indigenous riparian flora to uncover and explain novel adaptive mechanisms of flooding tolerance that may be introduced into crop species is also explored. The article begins by considering how, despite the essential role of water in sustaining plant life, floodwater can threaten its existence unless appropriate adaptations are present. Central to resolving the contradiction is the distinction between the essential role of cellular water as the source of electrons and protons used to build and operate the plant after combining with CO2 and O2 and the damaging role of extracellular water that, in excess, interferes with the union of these gases with photosynthetic or respiratory electrons and protons. PMID:26174144

Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production.

PubMed

Pérez-Montaño, F; Alías-Villegas, C; Bellogín, R A; del Cerro, P; Espuny, M R; Jiménez-Guerrero, I; López-Baena, F J; Ollero, F J; Cubo, T

2014-01-01

Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here. Copyright © 2013 Elsevier GmbH. All rights reserved.

Safety assessment and public concerns for genetically modified food products: the Japanese experience.

PubMed

Hino, Akihiro

2002-01-01

The recombinant DNA (rDNA) technique is expected to bring about great progress in the improvement of breeding technology and the development of new plant varieties showing high quality and high yield, such as those with excellent pest and disease resistance, those with environmental stress tolerance, and so forth. In the United States and Canada, many genetically modified (GM) crop plants were commercialized as early as 1994. In Japan, 35 transgenic crop plants, such as herbicide tolerant soybean, cotton, and canola, and insect-resistant corn, cotton, and potatos, were authorized and considered marketable until April 2001. The general public, however, is not familiar with rDNA technology, and some people seem to feel uncomfortable with biotechnology, frequently because of the difficulty of the technology and lacking of sufficient information. New labeling systems were initiated in April 2001 in Japan to provide information regarding the use of GM crops as raw material.

Biological mode of action of a nitrophenolates-based biostimulant: case study

PubMed Central

Przybysz, Arkadiusz; Gawrońska, Helena; Gajc-Wolska, Janina

2014-01-01

The challenges facing modern plant production involve (i) responding to the demand for food and resources of plant origin from the world's rapidly growing population, (ii) coping with the negative impact of stressful conditions mainly due to anthropopressure, and (iii) meeting consumers' new requirements and preferences for food that is high in nutritive value, natural, and free from harmful chemical additives. Despite employing the most modern plant cultivation technologies and the progress that has been made in breeding programs, the genetically-determined crop potential is still far from being fully exploited. Consequently yield and quality are often reduced, making production less, both profitable and attractive. There is an increasing desire to reduce the chemical input in agriculture and there has been a change toward integrated plant management and sustainable, environmentally-friendly systems. Biostimulants are a category of relatively new products of diverse formulations that positively affect a plant's vital processes and whose impact is usually more evident under stressful conditions. In this paper, information is provided on the mode of action of a nitrophenolates-based biostimulant, Atonik, in model species and economically important crops grown under both field and controlled conditions in a growth chamber. The effects of Atonik on plant morphology, physiology, biochemistry (crops and model plant) and yield and yield parameters (crops) is demonstrated. Effects of other biostimulants on studied in this work processes/parameters are also presented in discussion. PMID:25566287

Biological mode of action of a nitrophenolates-based biostimulant: case study.

PubMed

Przybysz, Arkadiusz; Gawrońska, Helena; Gajc-Wolska, Janina

2014-01-01

The challenges facing modern plant production involve (i) responding to the demand for food and resources of plant origin from the world's rapidly growing population, (ii) coping with the negative impact of stressful conditions mainly due to anthropopressure, and (iii) meeting consumers' new requirements and preferences for food that is high in nutritive value, natural, and free from harmful chemical additives. Despite employing the most modern plant cultivation technologies and the progress that has been made in breeding programs, the genetically-determined crop potential is still far from being fully exploited. Consequently yield and quality are often reduced, making production less, both profitable and attractive. There is an increasing desire to reduce the chemical input in agriculture and there has been a change toward integrated plant management and sustainable, environmentally-friendly systems. Biostimulants are a category of relatively new products of diverse formulations that positively affect a plant's vital processes and whose impact is usually more evident under stressful conditions. In this paper, information is provided on the mode of action of a nitrophenolates-based biostimulant, Atonik, in model species and economically important crops grown under both field and controlled conditions in a growth chamber. The effects of Atonik on plant morphology, physiology, biochemistry (crops and model plant) and yield and yield parameters (crops) is demonstrated. Effects of other biostimulants on studied in this work processes/parameters are also presented in discussion.

Research advances in major cereal crops for adaptation to abiotic stresses

PubMed Central

Maiti, RK; Satya, Pratik

2014-01-01

With devastating increase in population there is a great necessity to increase crop productivity of staple crops but the productivity is greatly affected by various abiotic stress factors such as drought, salinity. An attempt has been made a brief account on abiotic stress resistance of major cereal crops viz. In spite of good successes obtained on physiological and use molecular biology, the benefits of this high cost technology are beyond the reach of developing countries. This review discusses several morphological, anatomical, physiological, biochemical and molecular mechanisms of major cereal crops related to the adaptation of these crop to abiotic stress factors. It discusses the effect of abiotic stresses on physiological processes such as flowering, grain filling and maturation and plant metabolisms viz. photosynthesis, enzyme activity, mineral nutrition, and respiration. Though significant progress has been attained on the physiological, biochemical basis of resistance to abiotic stress factors, very little progress has been achieved to increase productivity under sustainable agriculture. Therefore, there is a great necessity of inter-disciplinary research to address this issue and to evolve efficient technology and its transfer to the farmers’ fields. PMID:25523172

Research advances in major cereal crops for adaptation to abiotic stresses.

PubMed

Maiti, R K; Satya, Pratik

2014-01-01

With devastating increase in population there is a great necessity to increase crop productivity of staple crops but the productivity is greatly affected by various abiotic stress factors such as drought, salinity. An attempt has been made a brief account on abiotic stress resistance of major cereal crops viz. In spite of good successes obtained on physiological and use molecular biology, the benefits of this high cost technology are beyond the reach of developing countries. This review discusses several morphological, anatomical, physiological, biochemical and molecular mechanisms of major cereal crops related to the adaptation of these crop to abiotic stress factors. It discusses the effect of abiotic stresses on physiological processes such as flowering, grain filling and maturation and plant metabolisms viz. photosynthesis, enzyme activity, mineral nutrition, and respiration. Though significant progress has been attained on the physiological, biochemical basis of resistance to abiotic stress factors, very little progress has been achieved to increase productivity under sustainable agriculture. Therefore, there is a great necessity of inter-disciplinary research to address this issue and to evolve efficient technology and its transfer to the farmers' fields.

Spatial variation of corn canopy temperature as dependent upon soil texture and crop rooting characteristics

NASA Technical Reports Server (NTRS)

Choudhury, B. J.

1983-01-01

A soil plant atmosphere model for corn (Zea mays L.) together with the scaling theory for soil hydraulic heterogeneity are used to study the sensitivity of spatial variation of canopy temperature to field averaged soil texture and crop rooting characteristics. The soil plant atmosphere model explicitly solves a continuity equation for water flux resulting from root water uptake, changes in plant water storage and transpirational flux. Dynamical equations for root zone soil water potential and the plant water storage models the progressive drying of soil, and day time dehydration and night time hydration of the crop. The statistic of scaling parameter which describes the spatial variation of soil hydraulic conductivity and matric potential is assumed to be independent of soil texture class. The field averaged soil hydraulic characteristics are chosen to be representative of loamy sand and clay loam soils. Two rooting characteristics are chosen, one shallow and the other deep rooted. The simulation shows that the range of canopy temperatures in the clayey soil is less than 1K, but for the sandy soil the range is about 2.5 and 5.0 K, respectively, for the shallow and deep rooted crops.

Research Progress on the use of Plant Allelopathy in Agriculture and the Physiological and Ecological Mechanisms of Allelopathy

PubMed Central

Cheng, Fang; Cheng, Zhihui

2015-01-01

Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop re-establishment) or negative effects (e.g., autotoxicity, soil sickness, or biological invasion). To ensure sustainable agricultural development, it is important to exploit cultivation systems that take advantage of the stimulatory/inhibitory influence of allelopathic plants to regulate plant growth and development and to avoid allelopathic autotoxicity. Allelochemicals can potentially be used as growth regulators, herbicides, insecticides, and antimicrobial crop protection products. Here, we reviewed the plant allelopathy management practices applied in agriculture and the underlying allelopathic mechanisms described in the literature. The major points addressed are as follows: (1) Description of management practices related to allelopathy and allelochemicals in agriculture. (2) Discussion of the progress regarding the mode of action of allelochemicals and the physiological mechanisms of allelopathy, consisting of the influence on cell micro- and ultra-structure, cell division and elongation, membrane permeability, oxidative and antioxidant systems, growth regulation systems, respiration, enzyme synthesis and metabolism, photosynthesis, mineral ion uptake, protein and nucleic acid synthesis. (3) Evaluation of the effect of ecological mechanisms exerted by allelopathy on microorganisms and the ecological environment. (4) Discussion of existing problems and proposal for future research directions in this field to provide a useful reference for future studies on plant allelopathy. PMID:26635845

[Progress on salt resistance in autopolyploid plants].

PubMed

Zhu, Hong Ju; Liu, Wen Ge

2018-04-20

Polyploidization is a key driving force that plays a vital role in the evolution of higher plants. Autopolyploid plants often demonstrate altered physiology phenomena due to the different genome composition and gene expression patterns. For example, autopolyploid plants are more resistant to stresses than their homologous diploid ancestors. Soil salinity and secondary salinization are two vital factors affecting crop production which severely limit the sustainable development of agriculture in China. Polyploid plants are important germplasm resources in crop genetic improvement due to their higher salt tolerance. Revealing the mechanism of salt tolerance in homologous plants will provide a foundation for breeding new plants with improved salt resistance. In this review, we describe the existing and ongoing characterization of the mechanism of salt tolerance in autopolyploid plants, including the salt tolerance evolution, physiology, biochemistry, cell structure and molecular level researches. Finally, we also discuss the prospects in this field by using polyploid watermelon as an example, which will be helpful in polyploid research and plant breeding.

Genome-editing technologies and their potential application in horticultural crop breeding

PubMed Central

Xiong, Jin-Song; Ding, Jing; Li, Yi

2015-01-01

Plant breeding, one of the oldest agricultural activities, parallels human civilization. Many crops have been domesticated to satisfy human's food and aesthetical needs, including numerous specialty horticultural crops such as fruits, vegetables, ornamental flowers, shrubs, and trees. Crop varieties originated through selection during early human civilization. Other technologies, such as various forms of hybridization, mutation, and transgenics, have also been invented and applied to crop breeding over the past centuries. The progress made in these breeding technologies, especially the modern biotechnology-based breeding technologies, has had a great impact on crop breeding as well as on our lives. Here, we first review the developmental process and applications of these technologies in horticultural crop breeding. Then, we mainly describe the principles of the latest genome-editing technologies and discuss their potential applications in the genetic improvement of horticultural crops. The advantages and challenges of genome-editing technologies in horticultural crop breeding are also discussed. PMID:26504570

Integrated genomics and molecular breeding approaches for dissecting the complex quantitative traits in crop plants.

PubMed

Kujur, Alice; Saxena, Maneesha S; Bajaj, Deepak; Laxmi; Parida, Swarup K

2013-12-01

The enormous population growth, climate change and global warming are now considered major threats to agriculture and world's food security. To improve the productivity and sustainability of agriculture, the development of highyielding and durable abiotic and biotic stress-tolerant cultivars and/climate resilient crops is essential. Henceforth, understanding the molecular mechanism and dissection of complex quantitative yield and stress tolerance traits is the prime objective in current agricultural biotechnology research. In recent years, tremendous progress has been made in plant genomics and molecular breeding research pertaining to conventional and next-generation whole genome, transcriptome and epigenome sequencing efforts, generation of huge genomic, transcriptomic and epigenomic resources and development of modern genomics-assisted breeding approaches in diverse crop genotypes with contrasting yield and abiotic stress tolerance traits. Unfortunately, the detailed molecular mechanism and gene regulatory networks controlling such complex quantitative traits is not yet well understood in crop plants. Therefore, we propose an integrated strategies involving available enormous and diverse traditional and modern -omics (structural, functional, comparative and epigenomics) approaches/resources and genomics-assisted breeding methods which agricultural biotechnologist can adopt/utilize to dissect and decode the molecular and gene regulatory networks involved in the complex quantitative yield and stress tolerance traits in crop plants. This would provide clues and much needed inputs for rapid selection of novel functionally relevant molecular tags regulating such complex traits to expedite traditional and modern marker-assisted genetic enhancement studies in target crop species for developing high-yielding stress-tolerant varieties.

Recent Advances in Utilizing Transcription Factors to Improve Plant Abiotic Stress Tolerance by Transgenic Technology

PubMed Central

Wang, Hongyan; Wang, Honglei; Shao, Hongbo; Tang, Xiaoli

2016-01-01

Agricultural production and quality are adversely affected by various abiotic stresses worldwide and this will be exacerbated by the deterioration of global climate. To feed a growing world population, it is very urgent to breed stress-tolerant crops with higher yields and improved qualities against multiple environmental stresses. Since conventional breeding approaches had marginal success due to the complexity of stress tolerance traits, the transgenic approach is now being popularly used to breed stress-tolerant crops. So identifying and characterizing the critical genes involved in plant stress responses is an essential prerequisite for engineering stress-tolerant crops. Far beyond the manipulation of single functional gene, engineering certain regulatory genes has emerged as an effective strategy now for controlling the expression of many stress-responsive genes. Transcription factors (TFs) are good candidates for genetic engineering to breed stress-tolerant crop because of their role as master regulators of many stress-responsive genes. Many TFs belonging to families AP2/EREBP, MYB, WRKY, NAC, bZIP have been found to be involved in various abiotic stresses and some TF genes have also been engineered to improve stress tolerance in model and crop plants. In this review, we take five large families of TFs as examples and review the recent progress of TFs involved in plant abiotic stress responses and their potential utilization to improve multiple stress tolerance of crops in the field conditions. PMID:26904044

Mechanisms and strategies of plant defense against Botrytis cinerea.

PubMed

AbuQamar, Synan; Moustafa, Khaled; Tran, Lam Son

2017-03-01

Biotic factors affect plant immune responses and plant resistance to pathogen infections. Despite the considerable progress made over the past two decades in manipulating genes, proteins and their levels from diverse sources, no complete genetic tolerance to environmental stresses has been developed so far in any crops. Plant defense response to pathogens, including Botrytis cinerea, is a complex biological process involving various changes at the biochemical, molecular (i.e. transcriptional) and physiological levels. Once a pathogen is detected, effective plant resistance activates signaling networks through the generation of small signaling molecules and the balance of hormonal signaling pathways to initiate defense mechanisms to the particular pathogen. Recently, studies using Arabidopsis thaliana and crop plants have shown that many genes are involved in plant responses to B. cinerea infection. In this article, we will review our current understanding of mechanisms regulating plant responses to B. cinerea with a particular interest on hormonal regulatory networks involving phytohormones salicylic acid (SA), jasmonic acid (JA), ethylene (ET) and abscisic acid (ABA). We will also highlight some potential gene targets that are promising for improving crop resistance to B. cinerea through genetic engineering and breeding programs. Finally, the role of biological control as a complementary and alternative disease management will be overviewed.

Adapting APSIM to model the physiology and genetics of complex adaptive traits in field crops.

PubMed

Hammer, Graeme L; van Oosterom, Erik; McLean, Greg; Chapman, Scott C; Broad, Ian; Harland, Peter; Muchow, Russell C

2010-05-01

Progress in molecular plant breeding is limited by the ability to predict plant phenotype based on its genotype, especially for complex adaptive traits. Suitably constructed crop growth and development models have the potential to bridge this predictability gap. A generic cereal crop growth and development model is outlined here. It is designed to exhibit reliable predictive skill at the crop level while also introducing sufficient physiological rigour for complex phenotypic responses to become emergent properties of the model dynamics. The approach quantifies capture and use of radiation, water, and nitrogen within a framework that predicts the realized growth of major organs based on their potential and whether the supply of carbohydrate and nitrogen can satisfy that potential. The model builds on existing approaches within the APSIM software platform. Experiments on diverse genotypes of sorghum that underpin the development and testing of the adapted crop model are detailed. Genotypes differing in height were found to differ in biomass partitioning among organs and a tall hybrid had significantly increased radiation use efficiency: a novel finding in sorghum. Introducing these genetic effects associated with plant height into the model generated emergent simulated phenotypic differences in green leaf area retention during grain filling via effects associated with nitrogen dynamics. The relevance to plant breeding of this capability in complex trait dissection and simulation is discussed.

Role of RNA interference in plant improvement

NASA Astrophysics Data System (ADS)

Jagtap, Umesh Balkrishna; Gurav, Ranjit Gajanan; Bapat, Vishwas Anant

2011-06-01

Research to alter crops for their better performance involving modern technology is underway in numerous plants, and achievements in transgenic plants are impacting crop improvements in unparalleled ways. Striking progress has been made using genetic engineering technology over the past two decades in manipulating genes from diverse and exotic sources, and inserting them into crop plants for inducing desirable characteristics. RNA interference (RNAi) has recently been identified as a natural mechanism for regulation of gene expression in all higher organisms from plants to humans and promises greater accuracy and precision to plant improvement. The expression of any gene can be down-regulated in a highly explicit manner exclusive of affecting the expression of any other gene by using RNAi technologies. Additional research in this field has been focused on a number of other areas including microRNAs, hairpin RNA, and promoter methylation. Manipulating new RNAi pathways, which generate small RNA molecules to amend gene expression in crops, can produce new quality traits and having better potentiality of protection against abiotic and biotic stresses. Nutritional improvement, change in morphology, or enhanced secondary metabolite synthesis are some of the other advantages of RNAi technology. In addition to its roles in regulating gene expression, RNAi is also used as a natural defense mechanism against molecular parasites such as jumping genes and viral genetic elements that affect genome stability. Even though much advancement has been made on the field of RNAi over the preceding few years, the full prospective of RNAi for crop improvement remains to be fully realized. The intricacy of RNAi pathway, the molecular machineries, and how it relates to plant development are still to be explained.

Advances in Agrobacterium tumefaciens-mediated genetic transformation of graminaceous crops.

PubMed

Singh, Roshan Kumar; Prasad, Manoj

2016-05-01

Steady increase in global population poses several challenges to plant science research, including demand for increased crop productivity, grain yield, nutritional quality and improved tolerance to different environmental factors. Transgene-based approaches are promising to address these challenges by transferring potential candidate genes to host organisms through different strategies. Agrobacterium-mediated gene transfer is one such strategy which is well known for enabling efficient gene transfer in both monocot and dicots. Due to its versatility, this technique underwent several advancements including development of improved in vitro plant regeneration system, co-cultivation and selection methods, and use of hyper-virulent strains of Agrobacterium tumefaciens harbouring super-binary vectors. The efficiency of this method has also been enhanced by the use of acetosyringone to induce the activity of vir genes, silver nitrate to reduce the Agrobacterium-induced necrosis and cysteine to avoid callus browning during co-cultivation. In the last two decades, extensive efforts have been invested towards achieving efficient Agrobacterium-mediated transformation in cereals. Though high-efficiency transformation systems have been developed for rice and maize, comparatively lesser progress has been reported in other graminaceous crops. In this context, the present review discusses the progress made in Agrobacterium-mediated transformation system in rice, maize, wheat, barley, sorghum, sugarcane, Brachypodium, millets, bioenergy and forage and turf grasses. In addition, it also provides an overview of the genes that have been recently transferred to these graminaceous crops using Agrobacterium, bottlenecks in this technique and future possibilities for crop improvement.

Molecular and genetic control of plant thermomorphogenesis.

PubMed

Quint, Marcel; Delker, Carolin; Franklin, Keara A; Wigge, Philip A; Halliday, Karen J; van Zanten, Martijn

2016-01-06

Temperature is a major factor governing the distribution and seasonal behaviour of plants. Being sessile, plants are highly responsive to small differences in temperature and adjust their growth and development accordingly. The suite of morphological and architectural changes induced by high ambient temperatures, below the heat-stress range, is collectively called thermomorphogenesis. Understanding the molecular genetic circuitries underlying thermomorphogenesis is particularly relevant in the context of climate change, as this knowledge will be key to rational breeding for thermo-tolerant crop varieties. Until recently, the fundamental mechanisms of temperature perception and signalling remained unknown. Our understanding of temperature signalling is now progressing, mainly by exploiting the model plant Arabidopsis thaliana. The transcription factor PHYTOCHROME INTERACTING FACTOR 4 (PIF4) has emerged as a critical player in regulating phytohormone levels and their activity. To control thermomorphogenesis, multiple regulatory circuits are in place to modulate PIF4 levels, activity and downstream mechanisms. Thermomorphogenesis is integrally governed by various light signalling pathways, the circadian clock, epigenetic mechanisms and chromatin-level regulation. In this Review, we summarize recent progress in the field and discuss how the emerging knowledge in Arabidopsis may be transferred to relevant crop systems.

Breeding approaches and genomics technologies to increase crop yield under low-temperature stress.

PubMed

Jha, Uday Chand; Bohra, Abhishek; Jha, Rintu

2017-01-01

Improved knowledge about plant cold stress tolerance offered by modern omics technologies will greatly inform future crop improvement strategies that aim to breed cultivars yielding substantially high under low-temperature conditions. Alarmingly rising temperature extremities present a substantial impediment to the projected target of 70% more food production by 2050. Low-temperature (LT) stress severely constrains crop production worldwide, thereby demanding an urgent yet sustainable solution. Considerable research progress has been achieved on this front. Here, we review the crucial cellular and metabolic alterations in plants that follow LT stress along with the signal transduction and the regulatory network describing the plant cold tolerance. The significance of plant genetic resources to expand the genetic base of breeding programmes with regard to cold tolerance is highlighted. Also, the genetic architecture of cold tolerance trait as elucidated by conventional QTL mapping and genome-wide association mapping is described. Further, global expression profiling techniques including RNA-Seq along with diverse omics platforms are briefly discussed to better understand the underlying mechanism and prioritize the candidate gene (s) for downstream applications. These latest additions to breeders' toolbox hold immense potential to support plant breeding schemes that seek development of LT-tolerant cultivars. High-yielding cultivars endowed with greater cold tolerance are urgently required to sustain the crop yield under conditions severely challenged by low-temperature.

Optimizing root system architecture in biofuel crops for sustainable energy production and soil carbon sequestration.

PubMed

To, Jennifer Pc; Zhu, Jinming; Benfey, Philip N; Elich, Tedd

2010-09-08

Root system architecture (RSA) describes the dynamic spatial configuration of different types and ages of roots in a plant, which allows adaptation to different environments. Modifications in RSA enhance agronomic traits in crops and have been implicated in soil organic carbon content. Together, these fundamental properties of RSA contribute to the net carbon balance and overall sustainability of biofuels. In this article, we will review recent data supporting carbon sequestration by biofuel crops, highlight current progress in studying RSA, and discuss future opportunities for optimizing RSA for biofuel production and soil carbon sequestration.

Modeling salt movement and halophytic crop growth on marginal lands with the APEX model

NASA Astrophysics Data System (ADS)

Goehring, N.; Saito, L.; Verburg, P.; Jeong, J.; Garrett, A.

2016-12-01

Saline soils negatively impact crop productivity in nearly 20% of irrigated agricultural lands worldwide. At these saline sites, cultivation of highly salt-tolerant plants, known as halophytes, may increase productivity compared to conventional salt-sensitive crops (i.e., glycophytes), thereby increasing the economic potential of marginal lands. Through a variety of mechanisms, halophytes are more effective than glycophytes at excluding, accumulating, and secreting salts from their tissues. Each mechanism can have a different impact on the salt balance in the plant-soil-water system. To date, little information is available to understand the long-term impacts of halophyte cultivation on environmental quality. This project utilizes the Agricultural Policy/Environmental Extender (APEX) model, developed by the US Department of Agriculture, to model the growth and production of two halophytic crops. The crops being modeled include quinoa (Chenopodium quinoa), which has utilities for human consumption and forage, and AC Saltlander green wheatgrass (Elymus hoffmannii), which has forage utility. APEX simulates salt movement between soil layers and accounts for the salt balance in the plant-soil-water system, including salinity in irrigation water and crop-specific salt uptake. Key crop growth parameters in APEX are derived from experimental growth data obtained under non-stressed conditions. Data from greenhouse and field experiments in which quinoa and AC Saltlander were grown under various soil salinity and irrigation salinity treatments are being used to parameterize, calibrate, and test the model. This presentation will discuss progress on crop parameterization and completed model runs under different salt-affected soil and irrigation conditions.

Plant Adaptation to Acid Soils: The Molecular Basis for Crop Aluminum Resistance.

PubMed

Kochian, Leon V; Piñeros, Miguel A; Liu, Jiping; Magalhaes, Jurandir V

2015-01-01

Aluminum (Al) toxicity in acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world's potentially arable soil is acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to Al toxicity has been a focus of intense research interest in the decade since the last article on crop acid soil tolerance was published in this journal. An impressive amount of progress has been made during that time that has greatly increased our understanding of the diversity of Al resistance genes and mechanisms, how resistance gene expression is regulated and triggered by Al and Al-induced signals, and how the proteins encoded by these genes function and are regulated. This review examines the state of our understanding of the physiological, genetic, and molecular bases for crop Al tolerance, looking at the novel Al resistance genes and mechanisms that have been identified over the past ten years. Additionally, it examines how the integration of molecular and genetic analyses of crop Al resistance is starting to be exploited for the improvement of crop plants grown on acid soils via both molecular-assisted breeding and biotechnology approaches.

Genomic Aspects of Research Involving Polyploid Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xiaohan; Ye, Chuyu; Tschaplinski, Timothy J

2011-01-01

Almost all extant plant species have spontaneously doubled their genomes at least once in their evolutionary histories, resulting in polyploidy which provided a rich genomic resource for evolutionary processes. Moreover, superior polyploid clones have been created during the process of crop domestication. Polyploid plants generated by evolutionary processes and/or crop domestication have been the intentional or serendipitous focus of research dealing with the dynamics and consequences of genome evolution. One of the new trends in genomics research is to create synthetic polyploid plants which provide materials for studying the initial genomic changes/responses immediately after polyploid formation. Polyploid plants are alsomore » used in functional genomics research to study gene expression in a complex genomic background. In this review, we summarize the recent progress in genomics research involving ancient, young, and synthetic polyploid plants, with a focus on genome size evolution, genomics diversity, genomic rearrangement, genetic and epigenetic changes in duplicated genes, gene discovery, and comparative genomics. Implications on plant sciences including evolution, functional genomics, and plant breeding are presented. It is anticipated that polyploids will be a regular subject of genomics research in the foreseeable future as the rapid advances in DNA sequencing technology create unprecedented opportunities for discovering and monitoring genomic and transcriptomic changes in polyploid plants. The fast accumulation of knowledge on polyploid formation, maintenance, and divergence at whole-genome and subgenome levels will not only help plant biologists understand how plants have evolved and diversified, but also assist plant breeders in designing new strategies for crop improvement.« less

Effect of crop residues on soil properties, plant growth, and crop yield. Agronomy Farm, Lincoln, Nebraska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Power, J.F.

1981-01-01

Progress is reported in a study designed to evaluate the effects of quantity of crop residues left on soil surface on soil properties, plant growth, and crop yield and to determine the effects of quantity of surface residues upon soil, fertilizer, and residue N transformations, availability, and efficiency of use. In a dryland corn-sorghum-soybean rotation produced on a clay loam, residues remaining after harvest of the previous crop were removed and respread on plots at rates of 0, 0.5, 1.0, and 1.5 times the quantity of residues originally present. The above crops were planted in four replications the following springmore » without tillage, after broadcasting 50 kg N/ha as ammonium nitrate. In 1980, /sup 15/N-depleted NH/sub 4/NO/sub 3/ was applied to half of each plot. After harvest, crop residues produced on the half-plot receiving the N-isotope were transferred to the half-plot receiving regular fertilizer, and visa versa. In 1981, /sup 15/N-depleted NH/sub 4/NO/sub 3/ was applied to half of each plot again, except at right angles to the fertilizer applied in 1980. After planting each year, thermocouples were installed in each plot and soil temperatures were recorded. Also access tubes were installed in all plots and soil water content was measured to the 150 cm soil depth periodically during the growing season. Dry matter production and N uptake by the plant tissue was measured periodically during the growing season and at maturity. Additional measurements taken included leaf area index, xylem water potentials, and soil microbial populations. Data are presented on corn and soybean production characteristics as affected by rate of crop residue on soil surface. Results are also given on leaf area index (LAI) and dry matter production of corn and soybeans as affected by surface residue rate. Total N content of corn and soybean plant materials and surface residues, and total and inorganic soil N (1980) are reported.« less

Transcription Factors Involved in Plant Resistance to Pathogens.

PubMed

Amorim, Lidiane L B; da Fonseca Dos Santos, Romulo; Neto, Joao Pacífico Bezerra; Guida-Santos, Mauro; Crovella, Sergio; Benko-Iseppon, Ana Maria

2017-01-01

Phytopathogenic microorganisms have a significant influence on survival and productivity of several crop plants. Transcription factors (TFs) are important players in the response to biotic stresses, as insect attack and pathogen infection. In face of such adversities many TFs families have been previously reported as differentially expressed in plants as a reaction to bacterial, fungal and viral infection. This review highlights recent progresses in understanding the structure, function, signal regulation and interaction of transcription factors with other proteins in response to pathogens. Hence, we focus on three families of transcription factors: ERF, bZIP and WRKY, due to their abundance, importance and the availability of functionally well-characterized members in response to pathogen attack. Their roles and the possibilities related to the use of this knowledge for engineering pathogen resistance in crop plants are also discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Strategies for transgenic nematode control in developed and developing world crops.

PubMed

Atkinson, Howard J; Lilley, Catherine J; Urwin, Peter E

2012-04-01

Nematodes cause an estimated $118b annual losses to world crops and they are not readily controlled by pesticides or other control options. For many crops natural resistance genes are unavailable to plant breeders or progress by this approach is slow. Transgenic plants can provide nematode resistance for such crops. Two approaches have been field trialled that control a wide range of nematodes by either limiting use of their dietary protein uptake from the crop or by preventing root invasion without a direct lethality. In addition, RNA interference increasingly in tandem with genomic studies is providing a range of potential resistance traits that involve no novel protein production. Transgenic resistance can be delivered by tissue specific promoters to just root tissues where most economic nematodes invade and feed rather than the harvested yield. High efficacy and durability can be provided by stacking nematode resistance traits including any that natural resistance provides. The constraints to uptake centre on market acceptance and not the availability of appropriate biotechnology. The need to deploy nematode resistance is intensifying with loss of pesticides, an increased need to protect crop profit margins and in many developing world countries where nematodes severely damage both commodity and staple crops. Copyright © 2011 Elsevier Ltd. All rights reserved.

Is genetic engineering ever going to take off in forage, turf and bioenergy crop breeding?

PubMed

Wang, Zeng-Yu; Brummer, E Charles

2012-11-01

Genetic engineering offers the opportunity to generate unique genetic variation that is either absent in the sexually compatible gene pool or has very low heritability. The generation of transgenic plants, coupled with breeding, has led to the production of widely used transgenic cultivars in several major cash crops, such as maize, soybean, cotton and canola. The process for regulatory approval of genetically engineered crops is slow and subject to extensive political interference. The situation in forage grasses and legumes is more complicated. Most widely grown forage, turf and bioenergy species (e.g. tall fescue, perennial ryegrass, switchgrass, alfalfa, white clover) are highly self-incompatible and outcrossing. Compared with inbreeding species, they have a high potential to pass their genes to adjacent plants. A major biosafety concern in these species is pollen-mediated transgene flow. Because human consumption is indirect, risk assessment of transgenic forage, turf and bioenergy species has focused on their environmental or ecological impacts. Although significant progress has been made in genetic modification of these species, commercialization of transgenic cultivars is very limited because of the stringent and costly regulatory requirements. To date, the only transgenic forage crop deregulated in the US is 'Roundup Ready' (RR) alfalfa. The approval process for RR alfalfa was complicated, involving several rounds of regulation, deregulation and re-regulation. Nevertheless, commercialization of RR alfalfa is an important step forward in regulatory approval of a perennial outcrossing forage crop. As additional transgenic forage, turf and bioenergy crops are generated and tested, different strategies have been developed to meet regulatory requirements. Recent progress in risk assessment and deregulation of transgenic forage and turf species is summarized and discussed.

Is genetic engineering ever going to take off in forage, turf and bioenergy crop breeding?

PubMed Central

Wang, Zeng-Yu; Brummer, E. Charles

2012-01-01

Background Genetic engineering offers the opportunity to generate unique genetic variation that is either absent in the sexually compatible gene pool or has very low heritability. The generation of transgenic plants, coupled with breeding, has led to the production of widely used transgenic cultivars in several major cash crops, such as maize, soybean, cotton and canola. The process for regulatory approval of genetically engineered crops is slow and subject to extensive political interference. The situation in forage grasses and legumes is more complicated. Scope Most widely grown forage, turf and bioenergy species (e.g. tall fescue, perennial ryegrass, switchgrass, alfalfa, white clover) are highly self-incompatible and outcrossing. Compared with inbreeding species, they have a high potential to pass their genes to adjacent plants. A major biosafety concern in these species is pollen-mediated transgene flow. Because human consumption is indirect, risk assessment of transgenic forage, turf and bioenergy species has focused on their environmental or ecological impacts. Although significant progress has been made in genetic modification of these species, commercialization of transgenic cultivars is very limited because of the stringent and costly regulatory requirements. To date, the only transgenic forage crop deregulated in the US is ‘Roundup Ready’ (RR) alfalfa. The approval process for RR alfalfa was complicated, involving several rounds of regulation, deregulation and re-regulation. Nevertheless, commercialization of RR alfalfa is an important step forward in regulatory approval of a perennial outcrossing forage crop. As additional transgenic forage, turf and bioenergy crops are generated and tested, different strategies have been developed to meet regulatory requirements. Recent progress in risk assessment and deregulation of transgenic forage and turf species is summarized and discussed. PMID:22378838

Recent progress in the use of ‘omics technologies in brassicaceous vegetables

PubMed Central

Witzel, Katja; Neugart, Susanne; Ruppel, Silke; Schreiner, Monika; Wiesner, Melanie; Baldermann, Susanne

2015-01-01

Continuing advances in ‘omics methodologies and instrumentation is enhancing the understanding of how plants cope with the dynamic nature of their growing environment. ‘Omics platforms have been only recently extended to cover horticultural crop species. Many of the most widely cultivated vegetable crops belong to the genus Brassica: these include plants grown for their root (turnip, rutabaga/swede), their swollen stem base (kohlrabi), their leaves (cabbage, kale, pak choi) and their inflorescence (cauliflower, broccoli). Characterization at the genome, transcript, protein and metabolite levels has illustrated the complexity of the cellular response to a whole series of environmental stresses, including nutrient deficiency, pathogen attack, heavy metal toxicity, cold acclimation, and excessive and sub-optimal irradiation. This review covers recent applications of ‘omics technologies to the brassicaceous vegetables, and discusses future scenarios in achieving improvements in crop end-use quality. PMID:25926843

Environmental release of living modified organisms: current approaches and case studies.

PubMed

Thomas, E; Nickson, Ph D

2005-01-01

Agricultural biotechnology is being rapidly adopted as evidenced by the acreage of genetically modified (GM) crops planted and tonnes of product (grain and fiber) harvested. Concurrent with this technological progress, is a growing concern that the worlds biological diversity is coming under increasing threat from human activities. As such, ecological risk assessment approaches are being developed for GM crop plants as international agreements regulating the transboundary movements of these products are being implemented. This paper reviews the ecological risk assessment approach that has been used to date to approve GM crops to date. The process has been case-by-case, using a comparative, science-based approach balancing the potential risks and benefits of the new technology versus those present with the currently accepted practices. The approach used to evaluate and approve these products is consistent with the conditions and requirements outlined in the Cartagena Protocol.

Biotechnological approaches for field applications of chitooligosaccharides (COS) to induce innate immunity in plants.

PubMed

Das, Subha Narayan; Madhuprakash, Jogi; Sarma, P V S R N; Purushotham, Pallinti; Suma, Katta; Manjeet, Kaur; Rambabu, Samudrala; Gueddari, Nour Eddine El; Moerschbacher, Bruno M; Podile, Appa Rao

2015-03-01

Plants have evolved mechanisms to recognize a wide range of pathogen-derived molecules and to express induced resistance against pathogen attack. Exploitation of induced resistance, by application of novel bioactive elicitors, is an attractive alternative for crop protection. Chitooligosaccharide (COS) elicitors, released during plant fungal interactions, induce plant defenses upon recognition. Detailed analyses of structure/function relationships of bioactive chitosans as well as recent progress towards understanding the mechanism of COS sensing in plants through the identification and characterization of their cognate receptors have generated fresh impetus for approaches that would induce innate immunity in plants. These progresses combined with the application of chitin/chitosan/COS in disease management are reviewed here. In considering the field application of COS, however, efficient and large-scale production of desired COS is a challenging task. The available methods, including chemical or enzymatic hydrolysis and chemical or biotechnological synthesis to produce COS, are also reviewed.

Application of CRISPR/Cas9 Genome Editing Technology for the Improvement of Crops Cultivated in Tropical Climates: Recent Progress, Prospects, and Challenges

PubMed Central

Haque, Effi; Taniguchi, Hiroaki; Hassan, Md. Mahmudul; Bhowmik, Pankaj; Karim, M. Rezaul; Śmiech, Magdalena; Zhao, Kaijun; Rahman, Mahfuzur; Islam, Tofazzal

2018-01-01

The world population is expected to increase from 7.3 to 9.7 billion by 2050. Pest outbreak and increased abiotic stresses due to climate change pose a high risk to tropical crop production. Although conventional breeding techniques have significantly increased crop production and yield, new approaches are required to further improve crop production in order to meet the global growing demand for food. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 (CRISPR-associated protein9) genome editing technology has shown great promise for quickly addressing emerging challenges in agriculture. It can be used to precisely modify genome sequence of any organism including plants to achieve the desired trait. Compared to other genome editing tools such as zinc finger nucleases (ZFNs) and transcriptional activator-like effector nucleases (TALENs), CRISPR/Cas9 is faster, cheaper, precise and highly efficient in editing genomes even at the multiplex level. Application of CRISPR/Cas9 technology in editing the plant genome is emerging rapidly. The CRISPR/Cas9 is becoming a user-friendly tool for development of non-transgenic genome edited crop plants to counteract harmful effects from climate change and ensure future food security of increasing population in tropical countries. This review updates current knowledge and potentials of CRISPR/Cas9 for improvement of crops cultivated in tropical climates to gain resiliency against emerging pests and abiotic stresses.

Application of CRISPR/Cas9 Genome Editing Technology for the Improvement of Crops Cultivated in Tropical Climates: Recent Progress, Prospects, and Challenges.

PubMed

Haque, Effi; Taniguchi, Hiroaki; Hassan, Md Mahmudul; Bhowmik, Pankaj; Karim, M Rezaul; Śmiech, Magdalena; Zhao, Kaijun; Rahman, Mahfuzur; Islam, Tofazzal

2018-01-01

The world population is expected to increase from 7.3 to 9.7 billion by 2050. Pest outbreak and increased abiotic stresses due to climate change pose a high risk to tropical crop production. Although conventional breeding techniques have significantly increased crop production and yield, new approaches are required to further improve crop production in order to meet the global growing demand for food. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 (CRISPR-associated protein9) genome editing technology has shown great promise for quickly addressing emerging challenges in agriculture. It can be used to precisely modify genome sequence of any organism including plants to achieve the desired trait. Compared to other genome editing tools such as zinc finger nucleases (ZFNs) and transcriptional activator-like effector nucleases (TALENs), CRISPR/Cas9 is faster, cheaper, precise and highly efficient in editing genomes even at the multiplex level. Application of CRISPR/Cas9 technology in editing the plant genome is emerging rapidly. The CRISPR/Cas9 is becoming a user-friendly tool for development of non-transgenic genome edited crop plants to counteract harmful effects from climate change and ensure future food security of increasing population in tropical countries. This review updates current knowledge and potentials of CRISPR/Cas9 for improvement of crops cultivated in tropical climates to gain resiliency against emerging pests and abiotic stresses.

High clearance phenotyping systems for season-long measurement of corn, sorghum and other row crops to complement unmanned aerial vehicle systems

NASA Astrophysics Data System (ADS)

Murray, Seth C.; Knox, Leighton; Hartley, Brandon; Méndez-Dorado, Mario A.; Richardson, Grant; Thomasson, J. Alex; Shi, Yeyin; Rajan, Nithya; Neely, Haly; Bagavathiannan, Muthukumar; Dong, Xuejun; Rooney, William L.

2016-05-01

The next generation of plant breeding progress requires accurately estimating plant growth and development parameters to be made over routine intervals within large field experiments. Hand measurements are laborious and time consuming and the most promising tools under development are sensors carried by ground vehicles or unmanned aerial vehicles, with each specific vehicle having unique limitations. Previously available ground vehicles have primarily been restricted to monitoring shorter crops or early growth in corn and sorghum, since plants taller than a meter could be damaged by a tractor or spray rig passing over them. Here we have designed two and already constructed one of these self-propelled ground vehicles with adjustable heights that can clear mature corn and sorghum without damage (over three meters of clearance), which will work for shorter row crops as well. In addition to regular RGB image capture, sensor suites are incorporated to estimate plant height, vegetation indices, canopy temperature and photosynthetically active solar radiation, all referenced using RTK GPS to individual plots. These ground vehicles will be useful to validate data collected from unmanned aerial vehicles and support hand measurements taken on plots.

Genetic modification of plant cell walls to enhance biomass yield and biofuel production in bioenergy crops.

PubMed

Wang, Yanting; Fan, Chunfen; Hu, Huizhen; Li, Ying; Sun, Dan; Wang, Youmei; Peng, Liangcai

2016-01-01

Plant cell walls represent an enormous biomass resource for the generation of biofuels and chemicals. As lignocellulose property principally determines biomass recalcitrance, the genetic modification of plant cell walls has been posed as a powerful solution. Here, we review recent progress in understanding the effects of distinct cell wall polymers (cellulose, hemicelluloses, lignin, pectin, wall proteins) on the enzymatic digestibility of biomass under various physical and chemical pretreatments in herbaceous grasses, major agronomic crops and fast-growing trees. We also compare the main factors of wall polymer features, including cellulose crystallinity (CrI), hemicellulosic Xyl/Ara ratio, monolignol proportion and uronic acid level. Furthermore, the review presents the main gene candidates, such as CesA, GH9, GH10, GT61, GT43 etc., for potential genetic cell wall modification towards enhancing both biomass yield and enzymatic saccharification in genetic mutants and transgenic plants. Regarding cell wall modification, it proposes a novel groove-like cell wall model that highlights to increase amorphous regions (density and depth) of the native cellulose microfibrils, providing a general strategy for bioenergy crop breeding and biofuel processing technology. Copyright © 2016 Elsevier Inc. All rights reserved.

Metabolic engineering of plant oils and waxes for use as industrial feedstocks.

PubMed

Vanhercke, Thomas; Wood, Craig C; Stymne, Sten; Singh, Surinder P; Green, Allan G

2013-02-01

Society has come to rely heavily on mineral oil for both energy and petrochemical needs. Plant lipids are uniquely suited to serve as a renewable source of high-value fatty acids for use as chemical feedstocks and as a substitute for current petrochemicals. Despite the broad variety of acyl structures encountered in nature and the cloning of many genes involved in their biosynthesis, attempts at engineering economic levels of specialty industrial fatty acids in major oilseed crops have so far met with only limited success. Much of the progress has been hampered by an incomplete knowledge of the fatty acid biosynthesis and accumulation pathways. This review covers new insights based on metabolic flux and reverse engineering studies that have changed our view of plant oil synthesis from a mostly linear process to instead an intricate network with acyl fluxes differing between plant species. These insights are leading to new strategies for high-level production of industrial fatty acids and waxes. Furthermore, progress in increasing the levels of oil and wax structures in storage and vegetative tissues has the potential to yield novel lipid production platforms. The challenge and opportunity for the next decade will be to marry these technologies when engineering current and new crops for the sustainable production of oil and wax feedstocks. © 2012 CSIRO Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Recent progress in drought and salt tolerance studies in Brassica crops

PubMed Central

Zhang, Xuekun; Lu, Guangyuan; Long, Weihua; Zou, Xiling; Li, Feng; Nishio, Takeshi

2014-01-01

Water deficit imposed by either drought or salinity brings about severe growth retardation and yield loss of crops. Since Brassica crops are important contributors to total oilseed production, it is urgently needed to develop tolerant cultivars to ensure yields under such adverse conditions. There are various physiochemical mechanisms for dealing with drought and salinity in plants at different developmental stages. Accordingly, different indicators of tolerance to drought or salinity at the germination, seedling, flowering and mature stages have been developed and used for germplasm screening and selection in breeding practices. Classical genetic and modern genomic approaches coupled with precise phenotyping have boosted the unravelling of genes and metabolic pathways conferring drought or salt tolerance in crops. QTL mapping of drought and salt tolerance has provided several dozen target QTLs in Brassica and the closely related Arabidopsis. Many drought- or salt-tolerant genes have also been isolated, some of which have been confirmed to have great potential for genetic improvement of plant tolerance. It has been suggested that molecular breeding approaches, such as marker-assisted selection and gene transformation, that will enhance oil product security under a changing climate be integrated in the development of drought- and salt-tolerant Brassica crops. PMID:24987291

CRISPR-Cas9: Tool for Qualitative and Quantitative Plant Genome Editing

PubMed Central

Noman, Ali; Aqeel, Muhammad; He, Shuilin

2016-01-01

Recent developments in genome editing techniques have aroused substantial excitement among agricultural scientists. These techniques offer new opportunities for developing improved plant lines with addition of important traits or removal of undesirable traits. Increased adoption of genome editing has been geared by swiftly developing Clustered regularly interspaced short palindromic repeats (CRISPR). This is appearing as driving force for innovative utilization in diverse branches of plant biology. CRISPR-Cas9 mediated genome editing is being used for rapid, easy and efficient alteration of genes among diverse plant species. With approximate completion of conceptual work about CRISPR-Cas9, plant scientists are applying this genome editing tool for crop attributes enhancement. The capability of this system for performing targeted and efficient modifications in genome sequence as well as gene expression will certainly spur novel developments not only in model plants but in crop and ornamental plants as well. Additionally, due to non-involvement of foreign DNA, this technique may help alleviating regulatory issues associated with genetically modified plants. We expect that prevailing challenges in plant science like genomic region manipulation, crop specific vectors etc. will be addressed along with sustained growth of this genome editing tool. In this review, recent progress of CRISPR-Cas9 technology in plants has been summarized and discussed. We reviewed significance of CRISPR-Cas9 for specific and non-traditional aspects of plant life. It also covers strengths of this technique in comparison with other genome editing techniques, e.g., Zinc finger nucleases, Transcription activator-like effector nucleases and potential challenges in coming decades have been described. PMID:27917188

Biological responses of wheat (Triticum aestivum) plants to the herbicide simetryne in soils.

PubMed

Jiang, Lei; Yang, Yi; Jia, Lin Xian; Lin, Jing Ling; Liu, Ying; Pan, Bo; Lin, Yong

2016-05-01

The rotation of rice and wheat is widely used and highly endorsed, and simetryne (s-triazine herbicide) is one of the principal herbicides widely used in this rotation for weed and grass control. However, little is known regarding the mechanism of the ecological and physiological effects of simetryne on wheat crops. In this study, we performed a comprehensive investigation of crop response to simetryne to elucidate the accumulation and phytotoxicity of the herbicide in wheat crops. Wheat plants exposed to 0.8 to 8.0mgkg(-1) simetryne for 7 d exhibited suppressed growth and decreased chlorophyll content. With simetryne concentration in the soil varied from 0.8mgkg(-1) to 8.0mgkg(-1), simetryne was progressively accumulated by the wheat plants. The accumulation of simetryne in the wheat plants not only induced the over production of ROS and injured the membrane lipids but also stimulated the production of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione S-transferase (GST). A test of enzymatic activity and gene expression illustrated that the wheat plants were wise enough to motivate the antioxidant enzymes through both molecular and physiological mechanisms to alleviate the simetryne-induced stress. This study offers an illuminating insight into the effective adaptive response of the wheat plants to the simetryne stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessment of the GHG Reduction Potential from Energy Crops Using a Combined LCA and Biogeochemical Process Models: A Review

PubMed Central

Jiang, Dong; Hao, Mengmeng; Wang, Qiao; Huang, Yaohuan; Fu, Xinyu

2014-01-01

The main purpose for developing biofuel is to reduce GHG (greenhouse gas) emissions, but the comprehensive environmental impact of such fuels is not clear. Life cycle analysis (LCA), as a complete comprehensive analysis method, has been widely used in bioenergy assessment studies. Great efforts have been directed toward establishing an efficient method for comprehensively estimating the greenhouse gas (GHG) emission reduction potential from the large-scale cultivation of energy plants by combining LCA with ecosystem/biogeochemical process models. LCA presents a general framework for evaluating the energy consumption and GHG emission from energy crop planting, yield acquisition, production, product use, and postprocessing. Meanwhile, ecosystem/biogeochemical process models are adopted to simulate the fluxes and storage of energy, water, carbon, and nitrogen in the soil-plant (energy crops) soil continuum. Although clear progress has been made in recent years, some problems still exist in current studies and should be addressed. This paper reviews the state-of-the-art method for estimating GHG emission reduction through developing energy crops and introduces in detail a new approach for assessing GHG emission reduction by combining LCA with biogeochemical process models. The main achievements of this study along with the problems in current studies are described and discussed. PMID:25045736

MicroRNA-mediated gene regulation: potential applications for plant genetic engineering.

PubMed

Zhou, Man; Luo, Hong

2013-09-01

Food security is one of the most important issues challenging the world today. Any strategies to solve this problem must include increasing crop yields and quality. MicroRNA-based genetic modification technology (miRNA-based GM tech) can be one of the most promising solutions that contribute to agricultural productivity directly by developing superior crop cultivars with enhanced biotic and abiotic stress tolerance and increased biomass yields. Indirectly, the technology may increase usage of marginal soils and decrease pesticide use, among other benefits. This review highlights the most recent progress of transgenic studies utilizing various miRNAs and their targets for plant trait modifications, and analyzes the potential of miRNA-mediated gene regulation for use in crop improvement. Strategies for manipulating miRNAs and their targets in transgenic plants including constitutive, stress-induced, or tissue-specific expression of miRNAs or their targets, RNA interference, expressing miRNA-resistant target genes, artificial target mimic and artificial miRNAs were discussed. We also discussed potential risks of utilizing miRNA-based GM tech. In general, miRNAs and their targets not only provide an invaluable source of novel transgenes, but also inspire the development of several new GM strategies, allowing advances in breeding novel crop cultivars with agronomically useful characteristics.

Genome editing as a tool to achieve the crop ideotype and de novo domestication of wild relatives: Case study in tomato.

PubMed

Zsögön, Agustin; Cermak, Tomas; Voytas, Dan; Peres, Lázaro Eustáquio Pereira

2017-03-01

The ideotype is a theoretical model of an archetypal cultivated plant. Recent progress in genome editing is aiding the pursuit of this ideal in crop breeding. Breeding is relatively straightforward when the traits in question are monogenic in nature and show Mendelian inheritance. Conversely, traits with a diffuse, polygenic basis such as abiotic stress resistance are more difficult to harness. In recent years, many genes have been identified that are important for plant domestication and act by increasing yield, grain or fruit size or altering plant architecture. Here, we propose that (a) key monogenic traits whose physiology has been unveiled can be molecularly tailored to achieve the ideotype; and (b) wild relatives of crops harboring polygenic stress resistance genes or other traits of interest could be de novo domesticated by manipulating monogenic yield-related traits through state-of-the-art gene editing techniques. An overview of the genomic and physiological challenges in the world's main staple crops is provided. We focus on tomato and its wild Solanum (section Lycopersicon) relatives as a suitable model for molecular design in the pursuit of the ideotype for elite cultivars and to test de novo domestication of wild relatives. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Unveiling the complexity of the maize transcriptome by single-molecule long-read sequencing

USDA-ARS?s Scientific Manuscript database

Zea mays is an important crop species and genetic model for elucidating transcriptional networks in plants. Uncertainties about the complete structure of mRNA transcripts, particularly with respect to alternatively spliced isoforms, limit the progress of research in this system. In this study, we us...

High-throughput profiling and analysis of plant responses over time to abiotic stress

USDA-ARS?s Scientific Manuscript database

Energy sorghum (Sorghum bicolor (L.) Moench) is a rapidly growing, high-biomass, annual crop prized for abiotic stress tolerance. Measuring genotype-by-environment (G x E) interactions remains a progress bottleneck. High throughput phenotyping within controlled environments has been proposed as a po...

Highlights of Recent Progress in Plant Lipid Research

USDA-ARS?s Scientific Manuscript database

Raw fossil material reserves are not inexhaustible and as prices continue to raise it is necessary to find new sources of alternative and renewable energy. Oils from oleaginous field crops (sunflower and rape) with properties close to those of fossil fuel could constitute an alternative source of en...

Application of genomics-assisted breeding for generation of climate resilient crops: progress and prospects

USDA-ARS?s Scientific Manuscript database

Climate change affects agricultural productivity worldwide. Increased prices of food commodities are the initial indication of drastic edible yield loss, which is expected to increase further due to global warming. This situation has compelled plant scientists to develop climate change-resilient cro...

Proteomes and Phosphoproteomes of Anther and Pollen: Availability and Progress.

PubMed

Zhang, Zaibao; Hu, Menghui; Feng, Xiaobing; Gong, Andong; Cheng, Lin; Yuan, Hongyu

2017-10-01

In flowering plants, anther development plays crucial role in sexual reproduction. Within the anther, microspore mother cells meiosis produces microspores, which further develop into pollen grains that play decisive role in plant reproduction. Previous studies on anther biology mainly focused on single gene functions relying on genetic and molecular methods. Recently, anther development has been expanded from multiple OMICS approaches like transcriptomics, proteomics/phosphoproteomics, and metabolomics. The development of proteomics techniques allowing increased proteome coverage and quantitative measurements of proteins which can characterize proteomes and their modulation during normal development, biotic and abiotic stresses in anther development. In this review, we summarize the achievements of proteomics and phosphoproteomics with anther and pollen organs from model plant and crop species (i.e. Arabidopsis, rice, tobacco). The increased proteomic information facilitated translation of information from the models to crops and thus aid in agricultural improvement. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The early response during the interaction of fungal phytopathogen and host plant.

PubMed

Shen, Yilin; Liu, Na; Li, Chuang; Wang, Xin; Xu, Xiaomeng; Chen, Wan; Xing, Guozhen; Zheng, Wenming

2017-05-01

Plants can be infected by a variety of pathogens, most of which can cause severe economic losses. The plants resist the invasion of pathogens via the innate or acquired immune system for surviving biotic stress. The associations between plants and pathogens are sophisticated beyond imaging and the interactions between them can occur at a very early stage after their touching each other. A number of researchers in the past decade have shown that many biochemical events appeared even as early as 5 min after their touching for plant disease resistance response. The early molecular interactions of plants and pathogens are likely to involve protein phosphorylation, ion fluxes, reactive oxygen species (ROS) and other signalling transduction. Here, we reviewed the recent progress in the study for molecular interaction response of fungal pathogens and host plant at the early infection stage, which included many economically important crop fungal pathogens such as cereal rust fungi, tomato Cladosporium fulvum , rice blast and so on. By dissecting the earlier infection stage of the diseases, the avirulent/virulent genes of pathogen or resistance genes of plant could be defined more clearly and accurately, which would undoubtedly facilitate fungal pathogenesis study and resistant crop breeding. © 2017 The Authors.

The early response during the interaction of fungal phytopathogen and host plant

PubMed Central

Shen, Yilin; Liu, Na; Li, Chuang; Wang, Xin; Xu, Xiaomeng; Chen, Wan; Xing, Guozhen

2017-01-01

Plants can be infected by a variety of pathogens, most of which can cause severe economic losses. The plants resist the invasion of pathogens via the innate or acquired immune system for surviving biotic stress. The associations between plants and pathogens are sophisticated beyond imaging and the interactions between them can occur at a very early stage after their touching each other. A number of researchers in the past decade have shown that many biochemical events appeared even as early as 5 min after their touching for plant disease resistance response. The early molecular interactions of plants and pathogens are likely to involve protein phosphorylation, ion fluxes, reactive oxygen species (ROS) and other signalling transduction. Here, we reviewed the recent progress in the study for molecular interaction response of fungal pathogens and host plant at the early infection stage, which included many economically important crop fungal pathogens such as cereal rust fungi, tomato Cladosporium fulvum, rice blast and so on. By dissecting the earlier infection stage of the diseases, the avirulent/virulent genes of pathogen or resistance genes of plant could be defined more clearly and accurately, which would undoubtedly facilitate fungal pathogenesis study and resistant crop breeding. PMID:28469008

Analysis of GMO Plum Plant Culture in System Operations Failure

NASA Technical Reports Server (NTRS)

Mercado, Dianne

2017-01-01

GMO plum trees are being evaluated at the Kennedy Space Center as a possible candidate for future space crops. Previously conducted horticultural testing compared the performance of several plum genotypes in controlled environment chambers, resulting in a down-selection to the NASA-11 genotype. Precursory studies determined the water use requirements to sustain the plants as well as the feasibility of grafting non-GMO plum scions onto GMO plum rootstocks of NASA-5, NASA-10, and NASA-11 genotypes. This study follows the growth and horticultural progress of plum trees and in-vitro cultures from August 2017 to November 2017, and provides supplemental support for future GMO plum studies. The presence of Hurricane Irma in early September 2017 resulted in the plants undergoing material deterioration from major changes to their overall horticultural progress.

Quantifying the effect of crop spatial arrangement on weed suppression using functional-structural plant modelling.

PubMed

Evers, Jochem B; Bastiaans, Lammert

2016-05-01

Suppression of weed growth in a crop canopy can be enhanced by improving crop competitiveness. One way to achieve this is by modifying the crop planting pattern. In this study, we addressed the question to what extent a uniform planting pattern increases the ability of a crop to compete with weed plants for light compared to a random and a row planting pattern, and how this ability relates to crop and weed plant density as well as the relative time of emergence of the weed. To this end, we adopted the functional-structural plant modelling approach which allowed us to explicitly include the 3D spatial configuration of the crop-weed canopy and to simulate intra- and interspecific competition between individual plants for light. Based on results of simulated leaf area development, canopy photosynthesis and biomass growth of the crop, we conclude that differences between planting pattern were small, particularly if compared to the effects of relative time of emergence of the weed, weed density and crop density. Nevertheless, analysis of simulated weed biomass demonstrated that a uniform planting of the crop improved the weed-suppression ability of the crop canopy. Differences in weed suppressiveness between planting patterns were largest with weed emergence before crop emergence, when the suppressive effect of the crop was only marginal. With simultaneous emergence a uniform planting pattern was 8 and 15 % more competitive than a row and a random planting pattern, respectively. When weed emergence occurred after crop emergence, differences between crop planting patterns further decreased as crop canopy closure was reached early on regardless of planting pattern. We furthermore conclude that our modelling approach provides promising avenues to further explore crop-weed interactions and aid in the design of crop management strategies that aim at improving crop competitiveness with weeds.

Management of Lesion Nematodes and Potato Early Dying with Rotation Crops

PubMed Central

LaMondia, J.A.

2006-01-01

Soil-incorporated rotation/green manure crops were evaluated for management of potato early dying caused by Verticillium dahliae and Pratylenchus penetrans. After two years of rotation/green manure and a subsequent potato crop, P. penetrans numbers were less after ‘Saia’ oat/‘Polynema’ marigold, ‘Triple S’ sorghum-sudangrass, or ‘Garry’ oat than ‘Superior’ potato or ‘Humus’ rapeseed. The area under the disease progress curve (AUDPC) for early dying was lowest after Saia oat/marigold, and tuber yields were greater than continuous potato after all crops except sorghum-sudangrass. Saia oat/marigold crops resulted in the greatest tuber yields. After one year of rotation/green manure, a marigold crop increased tuber yields and reduced AUDPC and P. penetrans. In the second potato crop after a single year of rotation, plots previously planted to marigolds had reduced P. penetrans densities and AUDPC and increased tuber yield. Rapeseed supported more P. penetrans than potato, but had greater yields. After two years of rotation/green manure crops and a subsequent potato crop, continuous potato had the highest AUDPC and lowest tuber weight. Rotation with Saia oats (2 yr) and Rudbeckia hirta (1 yr) reduced P. penetrans and increased tuber yields. AUDPC was lowest after R. hirta. Two years of sorghum-sudangrass did not affect P. penetrans, tuber yield or AUDPC. These results demonstrate that P. penetrans may be reduced by one or two years of rotation to non-host or antagonistic plants such as Saia oat, Polynema marigold, or R. hirta and that nematode control may reduce the severity of potato early dying. PMID:19259461

Soil Eukaryotic Microorganism Succession as Affected by Continuous Cropping of Peanut - Pathogenic and Beneficial Fungi were Selected

PubMed Central

Chen, Mingna; Li, Xiao; Yang, Qingli; Chi, Xiaoyuan; Pan, Lijuan; Chen, Na; Yang, Zhen; Wang, Tong; Wang, Mian; Yu, Shanlin

2012-01-01

Peanut is an important oil crop worldwide and shows considerable adaptability but growth and yield are negatively affected by continuous cropping. Soil micro-organisms are efficient bio-indicators of soil quality and plant health and are critical to the sustainability of soil-based ecosystem function and to successful plant growth. In this study, 18S rRNA gene clone library analyses were employed to study the succession progress of soil eukaryotic micro-organisms under continuous peanut cultivation. Eight libraries were constructed for peanut over three continuous cropping cycles and its representative growth stages. Cluster analyses indicated that soil micro-eukaryotic assemblages obtained from the same peanut cropping cycle were similar, regardless of growth period. Six eukaryotic groups were found and fungi predominated in all libraries. The fungal populations showed significant dynamic change and overall diversity increased over time under continuous peanut cropping. The abundance and/or diversity of clones affiliated with Eurotiales, Hypocreales, Glomerales, Orbiliales, Mucorales and Tremellales showed an increasing trend with continuous cropping but clones affiliated with Agaricales, Cantharellales, Pezizales and Pyxidiophorales decreased in abundance and/or diversity over time. The current data, along with data from previous studies, demonstrated that the soil microbial community was affected by continuous cropping, in particular, the pathogenic and beneficial fungi that were positively selected over time, which is commonplace in agro-ecosystems. The trend towards an increase in fungal pathogens and simplification of the beneficial fungal community could be important factors contributing to the decline in peanut growth and yield over many years of continuous cropping. PMID:22808226

Improving the Agronomy of Alyssum murale for Extensive Phytomining: A Five-Year Field Study.

PubMed

Bani, Aida; Echevarria, Guillaume; Sulçe, Sulejman; Morel, Jean Louis

2015-01-01

Large ultramafic areas exist in Albania, which could be suitable for phytomining with native Alyssum murale. We undertook a five-year field experiment on an ultramafic Vertisol, aimed at optimizing a low-cost Ni-phytoextraction crop of A. murale which is adapted to the Balkans. The following aspects were studied on 18-m2 plots in natural conditions: the effect of (i) plant phenology and element distribution, (ii) plant nutrition and fertilization, (iii) plant cover and weed control and (iv), planting technique (natural cover vs. sown crop). The optimal harvest time was set at the mid-flowering stage when Ni concentration and biomass yield were highest. The application of N, P, and K fertilizers, and especially a split 100-kg ha(-1) N application, increased the density of A. murale against all other species. It significantly increased shoot yield, without reducing Ni concentration. In natural stands, the control of graminaceous weeds required the use of an anti-monocots herbicide. However, after the optimization of fertilization and harvest time, weed control procured little benefit. Finally, cropping sown A. murale was more efficient than enhancing native stands and gave higher biomass and phytoextraction yields; biomass yields progressively improved from 0.3 to 9.0 t ha(-1) and phytoextracted Ni increased from 1.7 to 105 kg ha(-1).

Plants that attack plants: molecular elucidation of plant parasitism.

PubMed

Yoshida, Satoko; Shirasu, Ken

2012-12-01

Obligate parasitic plants in the family Orobanchaceae, such as Striga and Orobanche (including Phelipanche) spp., parasitize important crops and cause severe agricultural damage. Recent molecular studies have begun to reveal how these parasites have adapted to hosts in a parasitic lifecycle. The parasites detect nearby host roots and germinate by a mechanism that seems to have evolved from a conserved germination system found in non-parasites. The development of a specialized infecting organ called a haustorium is a unique feature of plant parasites and is triggered by host compounds and redox signals. Newly developed genomic and genetic resources will facilitate more rapid progress toward a molecular understanding of plant parasitism. Copyright © 2012 Elsevier Ltd. All rights reserved.

Improved conversion of herbaceous biomass to biofuels: Potential for modification of key plant characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sladden, S.E.; Bransby, D.I.

1989-10-01

Biomass crops are converted to fuels via biochemical and thermochemical processes. The process preferred depends on properties and cost of available feedstocks, and on the specific products desired. Since most mature biomass crops are composed of up to 80% cell wall fibers, the properties of these fibers determine, to a large degree, the conversion potential of the crop. However, biomass crops also contain small amounts of proteins, soluble carbohydrates and interfering materials (e.g., tannins and silica) which also influence the desirability of the feedstock in specific conversion processes. Fortunately, wide variation exists in the chemical composition of potential biomass crops.more » Although the chemical composition of feedstocks can be influenced significantly with judicious management has species selection, some traits are sufficiently heritable to permit breeding for improved feedstock composition. In addition to breeding for specific compositional traits directly, selection for in vitro digestibility or for easily-measured canopy or physiological traits may lead to more rapid and efficient progress in feedstock improvement, provided those measurements are highly-correlated with desirable feedstock composition. At the same time breeders must improve, or at least avoid damaging, stand longevity, tendency of plants to lodge, and establishment traits (e.g., disease resistance and seedling vigor). 46 refs., 8 tabs.« less

Weaving Together Space Biology and the Human Research Program: Selecting Crops and Manipulating Plant Physiology to Produce High Quality Food for ISS Astronauts

NASA Technical Reports Server (NTRS)

Massa, Gioia; Hummerick, Mary; Douglas, Grace; Wheeler, Raymond

2015-01-01

Researchers from the Human Research Program (HRP) have teamed up with plant biologists at KSC to explore the potential for plant growth and food production on the international space station (ISS) and future exploration missions. KSC Space Biology (SB) brings a history of plant and plant-microbial interaction research for station and for future bioregenerative life support systems. JSC HRP brings expertise in Advanced Food Technology (AFT), Advanced Environmental Health (AEH), and Behavioral Health and Performance (BHP). The Veggie plant growth hardware on the ISS is the platform that first drove these interactions. As we prepared for the VEG-01 validation test of Veggie, we engaged with BHP to explore questions that could be asked of the crew that would contribute both to plant and to behavioral health research. AFT, AEH and BHP stakeholders were engaged immediately after the return of the Veggie flight samples of space-grown lettuce, and this team worked with the JSC human medical offices to gain approvals for crew consumption of the lettuce on ISS. As we progressed with Veggie testing we began performing crop selection studies for Veggie that were initiated through AFT. These studies consisted of testing and down selecting leafy greens, dwarf tomatoes, and dwarf pepper crops based on characteristics of plant growth and nutritional levels evaluated at KSC, and organoleptic quality evaluated at JSCs Sensory Analysis lab. This work has led to a successful collaborative proposal to the International Life Sciences Research Announcement for a jointly funded HRP-SB investigation of the impacts of light quality and fertilizer on salad crop productivity, nutrition, and flavor in Veggie on the ISS. With this work, and potentially with other pending joint projects, we will continue the synergistic research that will advance the space biology knowledge base, help close gaps in the human research roadmap, and enable humans to venture out to Mars and beyond.

A 5-year analysis of crop phenologies from the United States Heartland (Invited)

NASA Astrophysics Data System (ADS)

Johnson, D. M.

2010-12-01

Time series imagery data from the National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) was intersected with annually updated field-level crop data from the United States Department of Agriculture (USDA) Farm Service Agency (FSA). Phenological metrics were derived for major crop types found in the United States (US) Heartland region. The specific MODIS data consisted of the 16-day composited Normalized Difference Vegetation Index (NDVI) 250 meter spatial resolution imagery from the Terra satellite. Crops evaluated included corn, soybeans, wheat, cotton, sorghum, rice, and other small grains. Charts showing the annual average state-level NDVI phenologies by crop were constructed for the five years between 2006 and 2010. The states of interest covered the intensively cultivated regions in the US Great Plains, Corn Belt, and Mississippi River Alluvial Plain. Results demonstrated the recent biophysical growth cycles of prevalent and widespread US crops and how they varied by geography and year. Linkages between the time series data and planting practices, weather impacts, crop progress reports, and yields were also investigated.

Root System Architecture and Abiotic Stress Tolerance: Current Knowledge in Root and Tuber Crops

PubMed Central

Khan, M. A.; Gemenet, Dorcus C.; Villordon, Arthur

2016-01-01

The challenge to produce more food for a rising global population on diminishing agricultural land is complicated by the effects of climate change on agricultural productivity. Although great progress has been made in crop improvement, so far most efforts have targeted above-ground traits. Roots are essential for plant adaptation and productivity, but are less studied due to the difficulty of observing them during the plant life cycle. Root system architecture (RSA), made up of structural features like root length, spread, number, and length of lateral roots, among others, exhibits great plasticity in response to environmental changes, and could be critical to developing crops with more efficient roots. Much of the research on root traits has thus far focused on the most common cereal crops and model plants. As cereal yields have reached their yield potential in some regions, understanding their root system may help overcome these plateaus. However, root and tuber crops (RTCs) such as potato, sweetpotato, cassava, and yam may hold more potential for providing food security in the future, and knowledge of their root system additionally focuses directly on the edible portion. Root-trait modeling for multiple stress scenarios, together with high-throughput phenotyping and genotyping techniques, robust databases, and data analytical pipelines, may provide a valuable base for a truly inclusive ‘green revolution.’ In the current review, we discuss RSA with special reference to RTCs, and how knowledge on genetics of RSA can be manipulated to improve their tolerance to abiotic stresses. PMID:27847508

Replacing fossil oil with fresh oil – with what and for what?

PubMed Central

Carlsson, Anders S; Yilmaz, Jenny Lindberg; Green, Allan G; Stymne, Sten; Hofvander, Per

2011-01-01

Industrial chemicals and materials are currently derived mainly from fossil-based raw materials, which are declining in availability, increasing in price and are a major source of undesirable greenhouse gas emissions. Plant oils have the potential to provide functionally equivalent, renewable and environmentally friendly replacements for these finite fossil-based raw materials, provided that their composition can be matched to end-use requirements, and that they can be produced on sufficient scale to meet current and growing industrial demands. Replacement of 40% of the fossil oil used in the chemical industry with renewable plant oils, whilst ensuring that growing demand for food oils is also met, will require a trebling of global plant oil production from current levels of around 139 MT to over 400 MT annually. Realisation of this potential will rely on application of plant biotechnology to (i) tailor plant oils to have high purity (preferably >90%) of single desirable fatty acids, (ii) introduce unusual fatty acids that have specialty end-use functionalities and (iii) increase plant oil production capacity by increased oil content in current oil crops, and conversion of other high biomass crops into oil accumulating crops. This review outlines recent progress and future challenges in each of these areas. Practical applications: The research reviewed in this paper aims to develop metabolic engineering technologies to radically increase the yield and alter the fatty acid composition of plant oils and enable the development of new and more productive oil crops that can serve as renewable sources of industrial feedstocks currently provided by non-renewable and polluting fossil-based resources. As a result of recent and anticipated research developments we can expect to see significant enhancements in quality and productivity of oil crops over the coming decades. This should generate the technologies needed to support increasing plant oil production into the future, hopefully of sufficient magnitude to provide a major supply of renewable plant oils for the industrial economy without encroaching on the higher priority demand for food oils. Achievement of this goal will make a significant contribution to moving to a sustainable carbon-neutral industrial society with lower emissions of carbon dioxide to the atmosphere and reduced environmental impact as a result. PMID:22102794

AQUAHOL: a developmental project. Technical progress report, November 1980-July 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodbridge, D.D.; Doering, W.C.

1981-07-01

During the period from November 1980 through July 1981, the potential of commercially growing cattails for use in making alcohol was studied by the Palm Beach Junior College and Sub-Grantee, Lantana Boatyard Inc. and a contractor, Gressinger and Sons Inc. The study involved the conversion of wild cattail rhizomes, roots, and nodal tissues to alcohol, the design of a basic harvesting mechanism, and the planting and growth of cattails on a commercial size acreage. Results of the study show that, alcohol can be made from cattails in greater quantities per acre than other considered crops; one of the factors withmore » using cattails as a commercial crop is the requirement for the development of specialized harvesting equipment; cattails will provide an excellent crop for marginal farm land that is often flooded or swampy and too wet for other crops. 71 refs., 46 figs., 1 tab.« less

The molecular mechanism of plant gravitropism.

PubMed

Wu, Di; Huang, Lin-zhou; Gao, Jin; Wang, Yong-hong

2016-07-20

Gravity is an important environmental factor that regulates plant growth and morphogenesis. In response to gravity stimulus, plants can set the optimum angle between the organs and the gravity vector. Plant gravitropism is divided into four sequential steps, including gravity perception, signal transduction, asymmetrical distribution of auxin, and organ curvature. In recent years, large numbers of mutants with defective gravitropism have been identified and genes involved in the regulation of gravitropism have been functionally characterized. In particular, progress has been achieved on elucidating the molecular mechanisms of gravity perception and asymmetrical distribution of auxin. As one of the most important strategies for plant to adapt environmental changes, gravitropism is also involved in the regulation of rice plant architecture and grain yield through modulating rice tiller angle. Therefore, the investigation of plant gravitropism not only contributes to decipher the regulatory mechanisms of plant growth and development, but also helps to guide the genetic improvement of crop architecture. However, the molecular mechanisms and regulatory network of gravitropism remain to be elusive. In this review, we focus on recent progress on elucidating molecular mechanisms underlying gravitropism and its involvement in regulating rice tiller angle, which is an important agronomic trait that determines rice plant architecture and thus grain yields.

A summary of porous tube plant nutrient delivery system investigations from 1985 to 1991

NASA Technical Reports Server (NTRS)

Dreschel, T. W.; Brown, C. S.; Piastuch, W. C.; Hinkle, C. R.; Sager, J. C.; Wheeler, R. M.; Knott, W. M.

1992-01-01

The Controlled Ecological Life Support System (CELSS) Program is a research effort to evaluate biological processes at a one person scale to provide air, water, and food for humans in closed environments for space habitation. This program focuses currently on the use of conventional crop plants and the use of hydroponic systems to grow them. Because conventional hydroponic systems are dependent on gravity to conduct solution flow, they cannot be used in the microgravity of space. Thus, there is a need for a system that will deliver water and nutrients to plant roots under microgravity conditions. The Plant Space Biology Program is interested in investigating the effect that the space environment has on the growth and development of plants. Thus, there is also a need to have a standard nutrient delivery method for growing plants in space for research into plant responses to microgravity. The Porous Tube Plant Nutrient Delivery System (PTPNDS) utilizes a hydrophilic, microporous material to control water and nutrient delivery to plant roots. It has been designed and analyzed to support plant growth independent of gravity and plans are progressing to test it in microgravity. It has been used successfully to grow food crops to maturity in an earth-bound laboratory. This document includes a bibliography and summary reports from the growth trials performed utilizing the PTPNDS.

Biotechnological approaches to study plant responses to stress.

PubMed

Pérez-Clemente, Rosa M; Vives, Vicente; Zandalinas, Sara I; López-Climent, María F; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized.

Biotechnological Approaches to Study Plant Responses to Stress

PubMed Central

Pérez-Clemente, Rosa M.; Vives, Vicente; Zandalinas, Sara I.; López-Climent, María F.; Muñoz, Valeria; Gómez-Cadenas, Aurelio

2013-01-01

Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upregulation of the antioxidant machinery, and accumulation of compatible solutes. Over the last few decades advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to abiotic stress conditions. In this paper, recent progresses on systematic analyses of plant responses to stress including genomics, proteomics, metabolomics, and transgenic-based approaches are summarized. PMID:23509757

Replace, reuse, recycle: improving the sustainable use of phosphorus by plants.

PubMed

Baker, Alison; Ceasar, S Antony; Palmer, Antony J; Paterson, Jaimie B; Qi, Wanjun; Muench, Stephen P; Baldwin, Stephen A

2015-06-01

The 'phosphorus problem' has recently received strong interest with two distinct strands of importance. The first is that too much phosphorus (P) is entering into waste water, creating a significant economic and ecological problem. Secondly, while agricultural demand for phosphate fertilizer is increasing to maintain crop yields, rock phosphate reserves are rapidly declining. Unravelling the mechanisms by which plants sense, respond to, and acquire phosphate can address both problems, allowing the development of crop plants that are more efficient at acquiring and using limited amounts of phosphate while at the same time improving the potential of plants and other photosynthetic organisms for nutrient recapture and recycling from waste water. In this review, we attempt to synthesize these important but often disparate parts of the debate in a holistic fashion, since solutions to such a complex problem require integrated and multidisciplinary approaches that address both P supply and demand. Rapid progress has been made recently in our understanding of local and systemic signalling mechanisms for phosphate, and of expression and regulation of membrane proteins that take phosphate up from the environment and transport it within the plant. We discuss the current state of understanding of such mechanisms involved in sensing and responding to phosphate stress. We also discuss approaches to improve the P-use efficiency of crop plants and future direction for sustainable use of P, including use of photosynthetic organisms for recapture of P from waste waters. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Transgenic strategies to confer resistance against viruses in rice plants

PubMed Central

Sasaya, Takahide; Nakazono-Nagaoka, Eiko; Saika, Hiroaki; Aoki, Hideyuki; Hiraguri, Akihiro; Netsu, Osamu; Uehara-Ichiki, Tamaki; Onuki, Masatoshi; Toki, Seichi; Saito, Koji; Yatou, Osamu

2014-01-01

Rice (Oryza sativa L.) is cultivated in more than 100 countries and supports nearly half of the world’s population. Developing efficient methods to control rice viruses is thus an urgent necessity because viruses cause serious losses in rice yield. Most rice viruses are transmitted by insect vectors, notably planthoppers and leafhoppers. Viruliferous insect vectors can disperse their viruses over relatively long distances, and eradication of the viruses is very difficult once they become widespread. Exploitation of natural genetic sources of resistance is one of the most effective approaches to protect crops from virus infection; however, only a few naturally occurring rice genes confer resistance against rice viruses. Many investigators are using genetic engineering of rice plants as a potential strategy to control viral diseases. Using viral genes to confer pathogen-derived resistance against crops is a well-established procedure, and the expression of various viral gene products has proved to be effective in preventing or reducing infection by various plant viruses since the 1990s. RNA interference (RNAi), also known as RNA silencing, is one of the most efficient methods to confer resistance against plant viruses on their respective crops. In this article, we review the recent progress, mainly conducted by our research group, in transgenic strategies to confer resistance against tenuiviruses and reoviruses in rice plants. Our findings also illustrate that not all RNAi constructs against viral RNAs are equally effective in preventing virus infection and that it is important to identify the viral “Achilles’ heel” gene to target for RNAi attack when engineering plants. PMID:24454308

Climate driven crop planting date in the ACME Land Model (ALM): Impacts on productivity and yield

NASA Astrophysics Data System (ADS)

Drewniak, B.

2017-12-01

Climate is one of the key drivers of crop suitability and productivity in a region. The influence of climate and weather on the growing season determine the amount of time crops spend in each growth phase, which in turn impacts productivity and, more importantly, yields. Planting date can have a strong influence on yields with earlier planting generally resulting in higher yields, a sensitivity that is also present in some crop models. Furthermore, planting date is already changing and may continue, especially if longer growing seasons caused by future climate change drive early (or late) planting decisions. Crop models need an accurate method to predict plant date to allow these models to: 1) capture changes in crop management to adapt to climate change, 2) accurately model the timing of crop phenology, and 3) improve crop simulated influences on carbon, nutrient, energy, and water cycles. Previous studies have used climate as a predictor for planting date. Climate as a plant date predictor has more advantages than fixed plant dates. For example, crop expansion and other changes in land use (e.g., due to changing temperature conditions), can be accommodated without additional model inputs. As such, a new methodology to implement a predictive planting date based on climate inputs is added to the Accelerated Climate Model for Energy (ACME) Land Model (ALM). The model considers two main sources of climate data important for planting: precipitation and temperature. This method expands the current temperature threshold planting trigger and improves the estimated plant date in ALM. Furthermore, the precipitation metric for planting, which synchronizes the crop growing season with the wettest months, allows tropical crops to be introduced to the model. This presentation will demonstrate how the improved model enhances the ability of ALM to capture planting date compared with observations. More importantly, the impact of changing the planting date and introducing tropical crops will be explored. Those impacts include discussions on productivity, yield, and influences on carbon and energy fluxes.

Food safety assessment of planting patterns of four vegetable-type crops grown in soil contaminated by electronic waste activities.

PubMed

Liu, Ling; Hu, Liangliang; Tang, Jianjun; Li, Yuefang; Zhang, Qian; Chen, Xin

2012-01-01

A field experiment was conducted to assess the effect of crop and planting pattern on levels of cadmium (Cd), lead (Pb), and copper (Cu) in crops grown in soil contaminated by electronic waste. The crops were maize (Zea mays L. var. Shentian-1), tomato (Solanum lycopersicum L. var. Zhongshu-4), cabbage (Brassica oleracea L. var. Jingfeng-1), and pakchoi (Brassica chinensis (L.) Makino. var. Youdonger-Hangzhou). The planting patterns were crop monoculture, crop co-planted with a legume, and crop co-planted with another crop. Metal concentrations in the edible parts of the crops varied with types of metals and crops. Pb concentration was higher in leafy vegetables (cabbage and pakchoi) than in maize or tomato, Cd concentration was higher in tomato and pakchoi than in maize or cabbage, and Cu concentration was higher in maize and pakchoi than in tomato or cabbage. Metal concentrations in the edible part were also influenced by planting pattern. Relative to monoculture, co-planting and especially co-planting with Japanese clover tended to decrease Pb accumulation and increase Cd accumulation. According to the maximum permissible concentration (MPC) standard of the National Standard Agency in China, only maize (under all planting patterns) could be safely consumed. Because co-planting tended to increase Cd accumulation even in maize, however, the results suggest that maize monoculture is the optimal crop and planting pattern for this kind of contaminated soil. Copyright © 2011 Elsevier Ltd. All rights reserved.

Developing trap cropping systems for effective organic management of key insect pests of cucurbit crops (IPM)

USDA-ARS?s Scientific Manuscript database

Trap cropping is a behaviorally-based pest management approach that functions by planting highly attractive plants next to a higher value crop so as to attract the pest to the trap crop plants, thus preventing or making less likely the arrival of the pest to the main crop (= cash crop). In 2012, a s...

Understanding crop genetic diversity under modern plant breeding.

PubMed

Fu, Yong-Bi

2015-11-01

Maximizing crop yield while at the same time minimizing crop failure for sustainable agriculture requires a better understanding of the impacts of plant breeding on crop genetic diversity. This review identifies knowledge gaps and shows the need for more research into genetic diversity changes under plant breeding. Modern plant breeding has made a profound impact on food production and will continue to play a vital role in world food security. For sustainable agriculture, a compromise should be sought between maximizing crop yield under changing climate and minimizing crop failure under unfavorable conditions. Such a compromise requires better understanding of the impacts of plant breeding on crop genetic diversity. Efforts have been made over the last three decades to assess crop genetic diversity using molecular marker technologies. However, these assessments have revealed some temporal diversity patterns that are largely inconsistent with our perception that modern plant breeding reduces crop genetic diversity. An attempt was made in this review to explain such discrepancies by examining empirical assessments of crop genetic diversity and theoretical investigations of genetic diversity changes over time under artificial selection. It was found that many crop genetic diversity assessments were not designed to assess diversity impacts from specific plant breeding programs, while others were experimentally inadequate and contained technical biases from the sampling of cultivars and genomes. Little attention has been paid to theoretical investigations on crop genetic diversity changes from plant breeding. A computer simulation of five simplified breeding schemes showed the substantial effects of plant breeding on the retention of heterozygosity over generations. It is clear that more efforts are needed to investigate crop genetic diversity in space and time under plant breeding to achieve sustainable crop production.

Airborne and ground-based remote sensing for the estimation of evapotranspiration and yield of bean, potato, and sugar beet crops

NASA Astrophysics Data System (ADS)

Jayanthi, Harikishan

The focus of this research was two-fold: (1) extend the reflectance-based crop coefficient approach to non-grain (potato and sugar beet), and vegetable crops (bean), and (2) develop vegetation index (VI)-yield statistical models for potato and sugar beet crops using high-resolution aerial multispectral imagery. Extensive crop biophysical sampling (leaf area index and aboveground dry biomass sampling) and canopy reflectance measurements formed the backbone of developing of canopy reflectance-based crop coefficients for bean, potato, and sugar beet crops in this study. Reflectance-based crop coefficient equations were developed for the study crops cultivated in Kimberly, Idaho, and subsequently used in water availability simulations in the plant root zone during 1998 and 1999 seasons. The simulated soil water profiles were compared with independent measurements of actual soil water profiles in the crop root zone in selected fields. It is concluded that the canopy reflectance-based crop coefficient technique can be successfully extended to non-grain crops as well. While the traditional basal crop coefficients generally expect uniform growth in a region the reflectance-based crop coefficients represent the actual crop growth pattern (in less than ideal water availability conditions) in individual fields. Literature on crop canopy interactions with sunlight states that there is a definite correspondence between leaf area index progression in the season and the final yield. In case of crops like potato and sugar beet, the yield is influenced not only on how early and how quickly the crop establishes its canopy but also on how long the plant stands on the ground in a healthy state. The integrated area under the crop growth curve has shown excellent correlations with hand-dug samples of potato and sugar beet crops in this research. Soil adjusted vegetation index-yield models were developed, and validated using multispectral aerial imagery. Estimated yield images were compared with the actual yields extracted from the ground. The remote sensing-derived yields compared well with the actual yields sampled on the ground. This research has highlighted the importance of the date of spectral emergence, the need to know the duration for which the crops stand on the ground, and the need to identify critical periods of time when multispectral coverages are essential for reliable tuber yield estimation.

The Genetic Control of Apomixis: Asexual Seed Formation

PubMed Central

Hand, Melanie L.; Koltunow, Anna M. G.

2014-01-01

Apomixis (asexual seed formation) is the result of a plant gaining the ability to bypass the most fundamental aspects of sexual reproduction: meiosis and fertilization. Without the need for male fertilization, the resulting seed germinates a plant that develops as a maternal clone. This dramatic shift in reproductive process has been documented in many flowering plant species, although no major seed crops have been shown to be capable of apomixis. The ability to generate maternal clones and therefore rapidly fix desirable genotypes in crop species could accelerate agricultural breeding strategies. The potential of apomixis as a next-generation breeding technology has contributed to increasing interest in the mechanisms controlling apomixis. In this review, we discuss the progress made toward understanding the genetic and molecular control of apomixis. Research is currently focused on two fronts. One aims to identify and characterize genes causing apomixis in apomictic species that have been developed as model species. The other aims to engineer or switch the sexual seed formation pathway in non-apomictic species, to one that mimics apomixis. Here we describe the major apomictic mechanisms and update knowledge concerning the loci that control them, in addition to presenting candidate genes that may be used as tools for switching the sexual pathway to an apomictic mode of reproduction in crops. PMID:24939990

It is a long way to GM agriculture.

PubMed

Van Montagu, Marc

2011-01-01

When we discovered that crown gall induction on plants by Agrobacterium tumefaciens is a natural event of genetic engineering, we were convinced that this was the dawn of a new era for plant science. Now, more than 30 years later, I remain overawed by how far and how rapidly we progressed with our knowledge of the molecular basis of plant growth, development, stress resistance, flowering, and ecological adaptation, thanks to the gene engineering technology. I am impressed, but also frustrated by the difficulties of applying this knowledge to improve crops and globally develop a sustainable and improved high-yielding agriculture. Now that gene engineering has become so efficient, I had hoped that thousands of teams, all over the world, would work on improving our major food crops, help domesticate new ones, and succeed in doubling or tripling biomass yields in industrial crops. We live in a world where more than a billion people are hungry or starving, while the last areas of tropical forest and wild nature are disappearing. We urgently need a better supply of raw material for our chemical industry because petroleum-based products pollute the environment and are limited in supply. Why could this new technology not bring the solutions to these challenges? Why has this not happened yet; what did we do wrong?

Genomic resources in fruit plants: an assessment of current status.

PubMed

Rai, Manoj K; Shekhawat, N S

2015-01-01

The availability of many genomic resources such as genome sequences, functional genomics resources including microarrays and RNA-seq, sufficient numbers of molecular markers, express sequence tags (ESTs) and high-density genetic maps is causing a rapid acceleration of genetics and genomic research of many fruit plants. This is leading to an increase in our knowledge of the genes that are linked to many horticultural and agronomically important traits. Recently, some progress has also been made on the identification and functional analysis of miRNAs in some fruit plants. This is one of the most active research fields in plant sciences. The last decade has witnessed development of genomic resources in many fruit plants such as apple, banana, citrus, grapes, papaya, pears, strawberry etc.; however, many of them are still not being exploited. Furthermore, owing to lack of resources, infrastructure and research facilities in many lesser-developed countries, development of genomic resources in many underutilized or less-studied fruit crops, which grow in these countries, is limited. Thus, research emphasis should be given to those fruit crops for which genomic resources are relatively scarce. The development of genomic databases of these less-studied fruit crops will enable biotechnologists to identify target genes that underlie key horticultural and agronomical traits. This review presents an overview of the current status of the development of genomic resources in fruit plants with the main emphasis being on genome sequencing, EST resources, functional genomics resources including microarray and RNA-seq, identification of quantitative trait loci and construction of genetic maps as well as efforts made on the identification and functional analysis of miRNAs in fruit plants.

A National Crop Progress Monitoring and Decision Support System Based on NASA Earth Science Results

NASA Astrophysics Data System (ADS)

di, L.; Yang, Z.

2009-12-01

Timely and accurate information on weekly crop progress and development is essential to a dynamic agricultural industry in the U. S. and the world. By law, the National Agricultural Statistics Service (NASS) of the U. S. Department of Agriculture’s (USDA) is responsible for monitoring and assessing U.S. agricultural production. Currently NASS compiles and issues weekly state and national crop progress and development reports based on reports from knowledgeable state and county agricultural officials and farmers. Such survey-based reports are subjectively estimated for an entire county, lack spatial coverage, and are labor intensive. There has been limited use of remote sensing data to assess crop conditions. NASS produces weekly 1-km resolution un-calibrated AVHRR-based NDVI static images to represent national vegetation conditions but there is no quantitative crop progress information. This presentation discusses the early result for developing a National Crop Progress Monitoring and Decision Support System. The system will overcome the shortcomings of the existing systems by integrating NASA satellite and model-based land surface and weather products, NASS’ wealth of internal crop progress and condition data and Cropland Data Layers (CDL), and the Farm Service Agency’s (FSA) Common Land Units (CLU). The system, using service-oriented architecture and web service technologies, will automatically produce and disseminate quantitative national crop progress maps and associated decision support data at 250-m resolution, as well as summary reports to support NASS and worldwide users in their decision-making. It will provide overall and specific crop progress for individual crops from the state level down to CLU field level to meet different users’ needs on all known croplands. This will greatly enhance the effectiveness and accuracy of the NASS aggregated crop condition data and charts of and provides objective and scientific evidence and guidance for the adjustment of NASS survey data. This presentation will discuss the architecture, Earth observation data, and the crop progress model used in the decision support system.

Citrus Genomics

PubMed Central

Talon, Manuel; Gmitter Jr., Fred G.

2008-01-01

Citrus is one of the most widespread fruit crops globally, with great economic and health value. It is among the most difficult plants to improve through traditional breeding approaches. Currently, there is risk of devastation by diseases threatening to limit production and future availability to the human population. As technologies rapidly advance in genomic science, they are quickly adapted to address the biological challenges of the citrus plant system and the world's industries. The historical developments of linkage mapping, markers and breeding, EST projects, physical mapping, an international citrus genome sequencing project, and critical functional analysis are described. Despite the challenges of working with citrus, there has been substantial progress. Citrus researchers engaged in international collaborations provide optimism about future productivity and contributions to the benefit of citrus industries worldwide and to the human population who can rely on future widespread availability of this health-promoting and aesthetically pleasing fruit crop. PMID:18509486

Soil health paradigms and implications for disease management.

PubMed

Larkin, Robert P

2015-01-01

Soil health has been defined as the capacity of soil to function as a vital living system to sustain biological productivity, maintain environmental quality, and promote plant, animal, and human health. Building and maintaining soil health are essential to agricultural sustainability and ecosystem function. Management practices that promote soil health, including the use of crop rotations, cover crops and green manures, organic amendments, and conservation tillage, also have generally positive effects on the management of soilborne diseases through a number of potential mechanisms, including increasing soil microbial biomass, activity, and diversity, resulting in greater biological suppression of pathogens and diseases. However, there also may be particular disease issues associated with some soil health management practices. In this review, research and progress made over the past twenty years regarding soil health, sustainability, and soil health management practices, with an emphasis on their implications for and effects on plant disease and disease management strategies, are summarized.

[Transgenic rice breeding for abiotic stress tolerance--present and future].

PubMed

Zhao, Feng-Yun; Zhang, Hui

2007-01-01

Environmental stresses and the continuing deterioration of arable land, along with an explosive increase in world population, pose serious threats to global agricultural production and food security. Improving the tolerance of the major crop plants to abiotic stresses has been a main goal in agriculture for a long time. As rice is considered one of the major crops, the development of new cultivars with enhanced abiotic stress-tolerance will undoubtedly have an important effect on global food production. The transgenic approach offers an attractive alternative to conventional techniques for the genetic improvement of rice cultivars. In recent years, an array of stress-related genes has already been transferred to rice to improve its resistance against abiotic stresses. Many transgenic rice plants with enhanced abiotic stress-tolerance have been obtained. This article focuses on the progress in the study of abiotic stress tolerance in transgenic rice breeding.

Gene Editing and Crop Improvement Using CRISPR-Cas9 System

PubMed Central

Arora, Leena; Narula, Alka

2017-01-01

Advancements in Genome editing technologies have revolutionized the fields of functional genomics and crop improvement. CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat)-Cas9 is a multipurpose technology for genetic engineering that relies on the complementarity of the guideRNA (gRNA) to a specific sequence and the Cas9 endonuclease activity. It has broadened the agricultural research area, bringing in new opportunities to develop novel plant varieties with deletion of detrimental traits or addition of significant characters. This RNA guided genome editing technology is turning out to be a groundbreaking innovation in distinct branches of plant biology. CRISPR technology is constantly advancing including options for various genetic manipulations like generating knockouts; making precise modifications, multiplex genome engineering, and activation and repression of target genes. The review highlights the progression throughout the CRISPR legacy. We have studied the rapid evolution of CRISPR/Cas9 tools with myriad functionalities, capabilities, and specialized applications. Among varied diligences, plant nutritional improvement, enhancement of plant disease resistance and production of drought tolerant plants are reviewed. The review also includes some information on traditional delivery methods of Cas9-gRNA complexes into plant cells and incorporates the advent of CRISPR ribonucleoproteins (RNPs) that came up as a solution to various limitations that prevailed with plasmid-based CRISPR system. PMID:29167680

Gene Editing and Crop Improvement Using CRISPR-Cas9 System.

PubMed

Arora, Leena; Narula, Alka

2017-01-01

Advancements in Genome editing technologies have revolutionized the fields of functional genomics and crop improvement. CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat)-Cas9 is a multipurpose technology for genetic engineering that relies on the complementarity of the guideRNA (gRNA) to a specific sequence and the Cas9 endonuclease activity. It has broadened the agricultural research area, bringing in new opportunities to develop novel plant varieties with deletion of detrimental traits or addition of significant characters. This RNA guided genome editing technology is turning out to be a groundbreaking innovation in distinct branches of plant biology. CRISPR technology is constantly advancing including options for various genetic manipulations like generating knockouts; making precise modifications, multiplex genome engineering, and activation and repression of target genes. The review highlights the progression throughout the CRISPR legacy. We have studied the rapid evolution of CRISPR/Cas9 tools with myriad functionalities, capabilities, and specialized applications. Among varied diligences, plant nutritional improvement, enhancement of plant disease resistance and production of drought tolerant plants are reviewed. The review also includes some information on traditional delivery methods of Cas9-gRNA complexes into plant cells and incorporates the advent of CRISPR ribonucleoproteins (RNPs) that came up as a solution to various limitations that prevailed with plasmid-based CRISPR system.

United States Department of Agriculture-Agricultural Research Service research on alternatives to methyl bromide: pre-plant and post-harvest.

PubMed

Schneider, Sally M; Rosskopf, Erin N; Leesch, James G; Chellemi, Daniel O; Bull, Carolee T; Mazzola, Mark

2003-01-01

Methyl bromide is a widely used fumigant for both pre-plant and post-harvest pest and pathogen control. The Montreal Protocol and the US Clean Air Act mandate a phase-out of the import and manufacture of methyl bromide, beginning in 2001 and culminating with a complete ban, except for quarantine and certain pre-shipment uses and exempted critical uses, in January 2005. In 1995, ARS built on its existing programs in soil-borne plant pathology and post-harvest entomology and plant pathology to initiate a national research program to develop alternatives to methyl bromide. The focus has been on strawberry, pepper, tomato, perennial and nursery cropping systems for pre-plant methyl bromide use and fresh and durable commodities for post-harvest use. Recently the program has been expanded to include research on alternatives for the ornamental and cut flower cropping systems. An overview of the national research program is presented. Results from four specific research trials are presented, ranging from organic to conventional systems. Good progress on short-term alternatives is being made. These will be used as the foundation of integrated management systems which begin with pre-plant management decisions and continue through post-harvest processing.

Molecular mechanisms underlying phosphate sensing, signaling, and adaptation in plants.

PubMed

Zhang, Zhaoliang; Liao, Hong; Lucas, William J

2014-03-01

As an essential plant macronutrient, the low availability of phosphorus (P) in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition, remobilization and recycling of phosphate (Pi) to maintain P homeostasis. Spatio-temporal molecular, physiological, and biochemical Pi deficiency responses developed by plants are the consequence of local and systemic sensing and signaling pathways. Pi deficiency is sensed locally by the root system where hormones serve as important signaling components in terms of developmental reprogramming, leading to changes in root system architecture. Root-to-shoot and shoot-to-root signals, delivered through the xylem and phloem, respectively, involving Pi itself, hormones, miRNAs, mRNAs, and sucrose, serve to coordinate Pi deficiency responses at the whole-plant level. A combination of chromatin remodeling, transcriptional and posttranslational events contribute to globally regulating a wide range of Pi deficiency responses. In this review, recent advances are evaluated in terms of progress toward developing a comprehensive understanding of the molecular events underlying control over P homeostasis. Application of this knowledge, in terms of developing crop plants having enhanced attributes for P use efficiency, is discussed from the perspective of agricultural sustainability in the face of diminishing global P supplies. © 2014 Institute of Botany, Chinese Academy of Sciences.

Satellite passive microwave detection of surface water inundation changes over the pan-Arctic from AMSR

NASA Astrophysics Data System (ADS)

Du, J.; Kimball, J. S.; Jones, L. A.; Watts, J. D.

2016-12-01

Climate is one of the key drivers of crop suitability and productivity in a region. The influence of climate and weather on the growing season determine the amount of time crops spend in each growth phase, which in turn impacts productivity and, more importantly, yields. Planting date can have a strong influence on yields with earlier planting generally resulting in higher yields, a sensitivity that is also present in some crop models. Furthermore, planting date is already changing and may continue, especially if longer growing seasons caused by future climate change drive early (or late) planting decisions. Crop models need an accurate method to predict plant date to allow these models to: 1) capture changes in crop management to adapt to climate change, 2) accurately model the timing of crop phenology, and 3) improve crop simulated influences on carbon, nutrient, energy, and water cycles. Previous studies have used climate as a predictor for planting date. Climate as a plant date predictor has more advantages than fixed plant dates. For example, crop expansion and other changes in land use (e.g., due to changing temperature conditions), can be accommodated without additional model inputs. As such, a new methodology to implement a predictive planting date based on climate inputs is added to the Accelerated Climate Model for Energy (ACME) Land Model (ALM). The model considers two main sources of climate data important for planting: precipitation and temperature. This method expands the current temperature threshold planting trigger and improves the estimated plant date in ALM. Furthermore, the precipitation metric for planting, which synchronizes the crop growing season with the wettest months, allows tropical crops to be introduced to the model. This presentation will demonstrate how the improved model enhances the ability of ALM to capture planting date compared with observations. More importantly, the impact of changing the planting date and introducing tropical crops will be explored. Those impacts include discussions on productivity, yield, and influences on carbon and energy fluxes.

Selection and Clonal Propagation of High Artemisinin Genotypes of Artemisia annua

PubMed Central

Wetzstein, Hazel Y.; Porter, Justin A.; Janick, Jules; Ferreira, Jorge F. S.; Mutui, Theophilus M.

2018-01-01

Artemisinin, produced in the glandular trichomes of Artemisia annua L. is a vital antimalarial drug effective against Plasmodium falciparum resistant to quinine-derived medicines. Although work has progressed on the semi-synthetic production of artemisinin, field production of A. annua remains the principal commercial source of the compound. Crop production of artemisia must be increased to meet the growing worldwide demand for artemisinin combination therapies (ACTs) to treat malaria. Grower artemisinin yields rely on plants generated from seeds from open-pollinated parents. Although selection has considerably increased plant artemisinin concentration in the past 15 years, seed-generated plants have highly variable artemisinin content that lowers artemisinin yield per hectare. Breeding efforts to produce improved F1 hybrids have been hampered by the inability to produce inbred lines due to self-incompatibility. An approach combining conventional hybridization and selection with clonal propagation of superior genotypes is proposed as a means to enhance crop yield and artemisinin production. Typical seed-propagated artemisia plants produce less than 1% (dry weight) artemisinin with yields below 25 kg/ha. Genotypes were identified producing high artemisinin levels of over 2% and possessing improved agronomic characteristics such as high leaf area and shoot biomass production. Field studies of clonally-propagated high-artemisinin plants verified enhanced plant uniformity and an estimated gross primary productivity of up to 70 kg/ha artemisinin, with a crop density of one plant m-2. Tissue culture and cutting protocols for the mass clonal propagation of A. annua were developed for shoot regeneration, rooting, acclimatization, and field cultivation. Proof of concept studies showed that both tissue culture-regenerated plants and rooted cutting performed better than plants derived from seed in terms of uniformity, yield, and consistently high artemisinin content. Use of this technology to produce plants with homogeneously-high artemisinin can help farmers markedly increase the artemisinin yield per cultivated area. This would lead to increased profit to farmers and decreased prices of ACT. PMID:29636758

Progress in plant protoplast research.

PubMed

Eeckhaut, Tom; Lakshmanan, Prabhu Shankar; Deryckere, Dieter; Van Bockstaele, Erik; Van Huylenbroeck, Johan

2013-12-01

In this review we focus on recent progress in protoplast regeneration, symmetric and asymmetric hybridization and novel technology developments. Regeneration of new species and improved culture techniques opened new horizons for practical breeding in a number of crops. The importance of protoplast sources and embedding systems is discussed. The study of reactive oxygen species effects and DNA (de)condensation, along with thorough phytohormone monitoring, are in our opinion the most promising research topics in the further strive for rationalization of protoplast regeneration. Following, fusion and fragmentation progress is summarized. Genomic, transcriptomic and proteomic studies have led to better insights in fundamental processes such as cell wall formation, cell development and chromosome rearrangements in fusion products, whether or not obtained after irradiation. Advanced molecular screening methods of both genome and cytoplasmome facilitate efficient screening of both symmetric and asymmetric fusion products. We expect that emerging technologies as GISH, high resolution melting and next generation sequencing will pay major contributions to our insights of genome creation and stabilization, mainly after asymmetric hybridization. Finally, we demonstrate agricultural valorization of somatic hybridization through enumerating recent introgression of diverse traits in a number of commercial crops.

An Overview of the Genetics of Plant Response to Salt Stress: Present Status and the Way Forward.

PubMed

Kaleem, Fawad; Shabir, Ghulam; Aslam, Kashif; Rasul, Sumaira; Manzoor, Hamid; Shah, Shahid Masood; Khan, Abdul Rehman

2018-04-02

Salinity is one of the major threats faced by the modern agriculture today. It causes multidimensional effects on plants. These effects depend upon the plant growth stage, intensity, and duration of the stress. All these lead to stunted growth and reduced yield, ultimately inducing economic loss to the farming community in particular and to the country in general. The soil conditions of agricultural land are deteriorating at an alarming rate. Plants assess the stress conditions, transmit the specific stress signals, and then initiate the response against that stress. A more complete understanding of plant response mechanisms and their practical incorporation in crop improvement is an essential step towards achieving the goal of sustainable agricultural development. Literature survey shows that investigations of plant stresses response mechanism are the focus area of research for plant scientists. Although these efforts lead to reveal different plant response mechanisms against salt stress, yet many questions still need to be answered to get a clear picture of plant strategy to cope with salt stress. Moreover, these studies have indicated the presence of a complicated network of different integrated pathways. In order to work in a progressive way, a review of current knowledge is critical. Therefore, this review aims to provide an overview of our understanding of plant response to salt stress and to indicate some important yet unexplored dynamics to improve our knowledge that could ultimately lead towards crop improvement.

7 CFR 760.814 - Calculation of acreage for crop losses other than prevented planted.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of the crop, as applicable, or actual acreage of the crop planted for harvest. (b) In cases where... good farming practices; and (4) Could reach maturity if each planting was harvested or would have been harvested. (c) In cases where there is multiple-cropped acreage, each crop may be eligible for disaster...

7 CFR 760.814 - Calculation of acreage for crop losses other than prevented planted.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of the crop, as applicable, or actual acreage of the crop planted for harvest. (b) In cases where... good farming practices; and (4) Could reach maturity if each planting was harvested or would have been harvested. (c) In cases where there is multiple-cropped acreage, each crop may be eligible for disaster...

[Roles of organic acid metabolism in plant adaptation to nutrient deficiency and aluminum toxicity stress].

PubMed

Wang, Jianfei; Shen, Qirong

2006-11-01

Organic acids not only act as the intermediates in carbon metabolism, but also exert key roles in the plant adaptation to nutrient deficiency and metal stress and in the plant-microbe interactions at root-soil interface. From the viewpoint of plant nutrition, this paper reviewed the research progress on the formation and physiology of organic acids in plant, and their functions in nitrogen metabolism, phosphorus and iron uptake, aluminum tolerance, and soil ecology. New findings in the membrane transport of organic acids and the biotechnological manipulation of organic acids in transgenic model were also discussed. This novel perspectives of organic acid metabolism and its potential manipulation might present a possibility to understand the fundamental aspects of plant physiology, and lead to the new strategies to obtain crop varieties better adapted to environmental and metal stress.

Role of redox homeostasis in thermo-tolerance under a climate change scenario

PubMed Central

de Pinto, Maria Concetta; Locato, Vittoria; Paradiso, Annalisa; De Gara, Laura

2015-01-01

Background Climate change predictions indicate a progressive increase in average temperatures and an increase in the frequency of heatwaves, which will have a negative impact on crop productivity. Over the last decade, a number of studies have addressed the question of how model plants or specific crops modify their metabolism when exposed to heat stress. Scope This review provides an overview of the redox pathways that contribute to how plants cope with heat stress. The focus is on the role of reactive oxygen species (ROS), redox metabolites and enzymes in the signalling pathways leading to the activation of defence responses. Additional attention is paid to the regulating mechanisms that lead to an increase in specific ROS-scavenging systems during heat stress, which have been studied in different model systems. Finally, increasing thermo-tolerance in model and crop plants by exposing them to heat acclimation or to exogenous treatments is discussed. Conclusions Although there is clear evidence that several strategies are specifically activated according to the intensity and the duration of heat stress, as well as the capacity of the different species or genotypes to overcome stress, an alteration in redox homeostasis seems to be a common event. Different mechanisms that act to enhance redox systems enable crops to overcome heat stress more effectively. Knowledge of thermo-tolerance within agronomic biodiversity is thus of key importance to enable researchers to identify new strategies for overcoming the impacts of climate change, and for decision-makers in planning for an uncertain future with new choices and options open to them. PMID:26034009

7 CFR 1437.504 - Notice of loss for covered tropical crops.

Code of Federal Regulations, 2013 CFR

2013-01-01

... crops the obligation to harvest ends with the end of the life-cycle for the plantings that were in... acreage for the full crop year in the case of a perennial plant and for the full life of the plants for... perennial plants, all production irrespective of whether the production occurs in the same crop year. (iii...

7 CFR 1437.504 - Notice of loss for covered tropical crops.

Code of Federal Regulations, 2012 CFR

2012-01-01

... crops the obligation to harvest ends with the end of the life-cycle for the plantings that were in... acreage for the full crop year in the case of a perennial plant and for the full life of the plants for... perennial plants, all production irrespective of whether the production occurs in the same crop year. (iii...

7 CFR 1437.504 - Notice of loss for covered tropical crops.

Code of Federal Regulations, 2014 CFR

2014-01-01

... crops the obligation to harvest ends with the end of the life-cycle for the plantings that were in... acreage for the full crop year in the case of a perennial plant and for the full life of the plants for... perennial plants, all production irrespective of whether the production occurs in the same crop year. (iii...

7 CFR 1437.504 - Notice of loss for covered tropical crops.

Code of Federal Regulations, 2011 CFR

2011-01-01

... crops the obligation to harvest ends with the end of the life-cycle for the plantings that were in... acreage for the full crop year in the case of a perennial plant and for the full life of the plants for... perennial plants, all production irrespective of whether the production occurs in the same crop year. (iii...

The Agrochemical Industry

NASA Astrophysics Data System (ADS)

Malte, A. M.; Lilani, A. T.

This chapter deals with the chemicals used in agriculture mainly to protect, preserve, and improve crop yields. The term "agrochemical" is used broadly. Much agrochemical research and some advanced development is directed toward the introduction of genes that may provide disease, insect, or viral resistance into plants or other organisms. Further progress is being made in improving the protein, fat, or carbohydrate composition of the plant itself. Microorganisms are being propagated and currently marketed that are insecticidal (e.g., Bacillus thuringiensis) fungi that are herbicidal, bacteria that are fungicidal, nematodes that are widely biocidal, and so on, are all products or candidate products for use in agriculture.

USSR Report, Agriculture.

DTIC Science & Technology

1986-07-11

when powdery mildew appears on the third leaf from the top. 7026 CSO: 1824/331 19 jFRS¶JAG-.6017i1 July 1986 MAJOR CROP PROGRESS AND WEATHER REPORTING...1- May 86) ................................................ 18 Winter Wheat Pests in Odessa Oblast Discussed (P.I. Susidko; ZASHCHITA RASTENIY, No 4... wheat was planted produced only 25.7 quintals of grain per hectare and in Voronezh Oblast -- 23.6 quintals per hectare. And on the Voronezh farms

Translational plant proteomics: a perspective.

PubMed

Agrawal, Ganesh Kumar; Pedreschi, Romina; Barkla, Bronwyn J; Bindschedler, Laurence Veronique; Cramer, Rainer; Sarkar, Abhijit; Renaut, Jenny; Job, Dominique; Rakwal, Randeep

2012-08-03

Translational proteomics is an emerging sub-discipline of the proteomics field in the biological sciences. Translational plant proteomics aims to integrate knowledge from basic sciences to translate it into field applications to solve issues related but not limited to the recreational and economic values of plants, food security and safety, and energy sustainability. In this review, we highlight the substantial progress reached in plant proteomics during the past decade which has paved the way for translational plant proteomics. Increasing proteomics knowledge in plants is not limited to model and non-model plants, proteogenomics, crop improvement, and food analysis, safety, and nutrition but to many more potential applications. Given the wealth of information generated and to some extent applied, there is the need for more efficient and broader channels to freely disseminate the information to the scientific community. This article is part of a Special Issue entitled: Translational Proteomics. Copyright © 2012 Elsevier B.V. All rights reserved.

The perspective crops for the bioregenerative human life support systems

NASA Astrophysics Data System (ADS)

Polonskiy, Vadim; Polonskaya, Janna

The perspective crops for the bioregenerative human life support systems V.I. Polonskiy, J.E. Polonskaya aKrasnoyarsk State Agrarian University, 660049, Krasnoyarsk, Russia In the nearest future the space missions will be too long. In this case it is necessary to provide the crew by vitamins, antioxidants, and water-soluble dietary fibers. These compounds will be produced by higher plants. There was not enough attention at present to increasing content of micronutrients in edible parts of crops candidates for CELSS. We suggested to add the new crops to this list. 1. Barley -is the best crop for including to food crops (wheat, rice, soybean). Many of the health effects of barley are connected to dietary fibers beta-glucan of barley grains. Bar-ley is the only seed from cereals including wheat with content of all eight tocopherols (vitamin E, important antioxidant). Barley grains contain much greater amounts of phenolic compounds (potential antioxidant activities) than other cereal grains. Considerable focus is on supplement-ing wheat-based breads with barley to introduce the inherent nutritional advantages of barley flour, currently only 20We have selected and tested during 5 generations two high productive barley lines -1-K-O and 25-K-O. Our investigations (special breeding program for improving grain quality of barley) are in progress. 2. Volatile crops. Young leaves and shoots of these crops are edible and have a piquant taste. A lot of organic volatile compounds, oils, vitamins, antioxidants are in their biomass. These micronutrients are useful for good appetite and health of the crew. We have investigated 11 species: basil (Ocimum basilicum), hyssop (Hyssopus officinalis), marjoram (Origanum majorana), sweet-Mary (Melissa officinalis), common thyme (Thymus vulgaris), creeping thyme (Thymus serpyllum), summer savory (Satureja hortensis), catnip (Nepeta cataria), rue (Ruta graveolens), coriander (Coriandrum Ativum), sulfurwort (Levisticum officinale). These plants were grown under artificial light conditions from 5 to 7 months. All crops were cut periodically in every month. On the base of our investigations it is possible to recommend for using in CELSS the next crops: marjoram, sweet-Mary and common thyme. The micronutrients containing in barley and above mentioned volatile crops will be useful for good appetite and health of the crew.

Cryobiotechnology of apple (Malus spp.): development, progress and future prospects.

PubMed

Wang, Min-Rui; Chen, Long; Teixeira da Silva, Jaime A; Volk, Gayle M; Wang, Qiao-Chun

2018-05-01

Cryopreservation provides valuable genes for further breeding of elite cultivars, and cryotherapy improves the production of virus-free plants in Malus spp., thus assisting the sustainable development of the apple industry. Apple (Malus spp.) is one of the most economically important temperate fruit crops. Wild Malus genetic resources and existing cultivars provide valuable genes for breeding new elite cultivars and rootstocks through traditional and biotechnological breeding programs. These valuable genes include those resistant to abiotic factors such as drought and salinity, and to biotic factors such as fungi, bacteria and aphids. Over the last three decades, great progress has been made in apple cryobiology, making Malus one of the most extensively studied plant genera with respect to cryopreservation. Explants such as pollen, seeds, in vivo dormant buds, and in vitro shoot tips have all been successfully cryopreserved, and large Malus cryobanks have been established. Cryotherapy has been used for virus eradication, to obtain virus-free apple plants. Cryopreservation provided valuable genes for further breeding of elite cultivars, and cryotherapy improved the production of virus-free plants in Malus spp., thus assisting the sustainable development of the apple industry. This review provides updated and comprehensive information on the development and progress of apple cryopreservation and cryotherapy. Future research will reveal new applications and uses for apple cryopreservation and cryotherapy.

Grand challenges for crop science

USDA-ARS?s Scientific Manuscript database

Crop science is a highly integrative science using the disciplines of conventional plant breeding, transgenic crop improvement, plant physiology, and cropping system sciences to develop improved varieties of agronomic, turf, and forage crops to produce feed, food, fuel, and fiber for our world's gro...

Cura Annonae-Chemically Boosting Crop Yields Through Metabolic Feeding of a Plant Signaling Precursor.

PubMed

Vocadlo, David J

2017-05-22

The cream of the crop: With the world facing a projected shortfall of crops by 2050, new approaches are needed to boost crop yields. Metabolic feeding of plants with photocaged trehalose-6-phosphate (Tre6P) can increase levels of the signaling metabolite Tre6P in the plant. Reprogramming of cellular metabolism by Tre6P stimulates a program of plant growth and enhanced crop yields, while boosting starch content. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Low crop plant population densities promote pollen-mediated gene flow in spring wheat (Triticum aestivum L.).

PubMed

Willenborg, Christian J; Brûlé-Babel, Anita L; Van Acker, Rene C

2009-12-01

Transgenic wheat is currently being field tested with the intent of eventual commercialization. The development of wheat genotypes with novel traits has raised concerns regarding the presence of volunteer wheat populations and the role they may play in facilitating transgene movement. Here, we report the results of a field experiment that investigated the potential of spring wheat plant population density and crop height to minimize gene flow from a herbicide-resistant (HR) volunteer population to a non-HR crop. Pollen-mediated gene flow (PMGF) between the HR volunteer wheat population and four conventional spring wheat genotypes varying in height was assessed over a range of plant population densities. Natural hybridization events between the two cultivars were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) families. PMGF was strongly associated with crop yield components, but showed no association with flowering synchrony. Maximum observed PMGF was always less than 0.6%, regardless of crop height and density. The frequency of PMGF in spring wheat decreased exponentially with increasing plant population density, but showed no dependence on either crop genotype or height. However, increasing plant densities beyond the recommended planting rate of 300 cropped wheat plants m(-2) provided no obvious benefit to reducing PMGF. Nevertheless, our results demonstrate a critical plant density of 175-200 cropped wheat plants m(-2) below which PMGF frequencies rise exponentially with decreasing plant density. These results will be useful in the development of mechanistic models and best management practices that collectively facilitate the coexistence of transgenic and nontransgenic wheat crops.

Fungal Plant Pathogens Associated with Emerging Crops in North America: An Emerging Challenge for Plant Health Professionals

USDA-ARS?s Scientific Manuscript database

'Emerging crops' is a term typically applied to ethnic food plants, or plants used in traditional or ethnic medicine, some of which are becoming viable niche markets in North America. Information on crop protection of these plants is often scarce to lacking. Literature providing information on diagn...

Advancing Crop Transformation in the Era of Genome Editing[OPEN

PubMed Central

Blechl, Ann E.; Brutnell, Thomas P.; Conrad, Liza J.; Gelvin, Stanton B.; Jackson, David P.; Kausch, Albert P.; Lemaux, Peggy G.; Medford, June I.; Orozco-Cárdenas, Martha L.; Tricoli, David M.; Van Eck, Joyce; Voytas, Daniel F.

2016-01-01

Plant transformation has enabled fundamental insights into plant biology and revolutionized commercial agriculture. Unfortunately, for most crops, transformation and regeneration remain arduous even after more than 30 years of technological advances. Genome editing provides novel opportunities to enhance crop productivity but relies on genetic transformation and plant regeneration, which are bottlenecks in the process. Here, we review the state of plant transformation and point to innovations needed to enable genome editing in crops. Plant tissue culture methods need optimization and simplification for efficiency and minimization of time in culture. Currently, specialized facilities exist for crop transformation. Single-cell and robotic techniques should be developed for high-throughput genomic screens. Plant genes involved in developmental reprogramming, wound response, and/or homologous recombination should be used to boost the recovery of transformed plants. Engineering universal Agrobacterium tumefaciens strains and recruiting other microbes, such as Ensifer or Rhizobium, could facilitate delivery of DNA and proteins into plant cells. Synthetic biology should be employed for de novo design of transformation systems. Genome editing is a potential game-changer in crop genetics when plant transformation systems are optimized. PMID:27335450

Novel and potential application of cryopreservation to plant genetic transformation.

PubMed

Wang, Biao; Zhang, Zhibo; Yin, Zhenfang; Feng, Chaohong; Wang, Qiaochun

2012-01-01

The world population now is 6.7 billion and is predicted to reach 9 billion by 2050. Such a rapid growing population has tremendously increased the challenge for food security. Obviously, it is impossible for traditional agriculture to ensure the food security, while plant biotechnology offers considerable potential to realize this goal. Over the last 15 years, great benefits have been brought to sustainable agriculture by commercial cultivation of genetically modified (GM) crops. Further development of new GM crops will with no doubt contribute to meeting the requirements for food by the increasing population. The present article provides updated comprehensive information on novel and potential application of cryopreservation to genetic transformation. The major progresses that have been achieved in this subject include (1), long-term storage of a large number of valuable plant genes, which offers a good potential for further development of novel cultivars by genetic transformation; (2), retention of regenerative capacity of embryogenic tissues and protoplasts, which ensures efficient plant regeneration system for genetic transformation; (3), improvement of transformation efficiency and plant regeneration of transformed cells; (4), long-term preservation of transgenic materials with stable expression of transgenes and productive ability of recombinant proteins, which allows transgenic materials to be stored in a safe manner before being analyzed and evaluated, and allows establishment of stable seed stocks for commercial production of homologous proteins. Data provided in this article clearly demonstrate that cryo-technique has an important role to play in the whole chain of genetic transformation. Further studies coupling cryotechnique and genetic transformation are expected to significantly improve development of new GM crops. Copyright © 2011 Elsevier Inc. All rights reserved.

Big Data in Plant Science: Resources and Data Mining Tools for Plant Genomics and Proteomics.

PubMed

Popescu, George V; Noutsos, Christos; Popescu, Sorina C

2016-01-01

In modern plant biology, progress is increasingly defined by the scientists' ability to gather and analyze data sets of high volume and complexity, otherwise known as "big data". Arguably, the largest increase in the volume of plant data sets over the last decade is a consequence of the application of the next-generation sequencing and mass-spectrometry technologies to the study of experimental model and crop plants. The increase in quantity and complexity of biological data brings challenges, mostly associated with data acquisition, processing, and sharing within the scientific community. Nonetheless, big data in plant science create unique opportunities in advancing our understanding of complex biological processes at a level of accuracy without precedence, and establish a base for the plant systems biology. In this chapter, we summarize the major drivers of big data in plant science and big data initiatives in life sciences with a focus on the scope and impact of iPlant, a representative cyberinfrastructure platform for plant science.

Performance of soil-applied FeEDDHA isomers in delivering Fe to soybean plants in relation to the moment of application.

PubMed

Schenkeveld, Walter D C; Reichwein, Arjen M; Bugter, Marcel H J; Temminghoff, Erwin J M; van Riemsdijk, Willem H

2010-12-22

FeEDDHA (iron(3+) ethylenediamine-N,N'-bis(hydroxyphenylacetic acid) products are commonly applied to mend and prevent Fe deficiency chlorosis in soil-grown crops. Plants mainly take up Fe in the progressed vegetative and in the reproductive stages. This study examined which of the principal constituents of FeEDDHA products (the isomers racemic o,o-FeEDDHA, meso o,o-FeEDDHA, and o,p-FeEDDHA), most effectively meets the Fe requirements of soybean plants (Glycine max (L.) Merr.) grown on calcareous soil in the aforementioned growth stages. FeEDDHA isomers were applied once, separately or in mixtures, at t = 0, in the progressed vegetative stage or in the reproductive stage. o,p-FeEDDHA did not significantly contribute to Fe uptake in either growth stage. Both racemic and meso o,o-FeEDDHA were effective in supplying plants with Fe, approximately to the same extent. The moment of application had a significant effect on yield and FeEDDHA pore water concentrations at harvest, but not on Fe uptake. To optimize yield while minimizing FeEDDHA dosage, FeEDDHA is best applied to soybean plants prior to the onset of chorosis.

Triacylglycerol Metabolism, Function, and Accumulation in Plant Vegetative Tissues

DOE PAGES

Xu, Changcheng; Shanklin, John

2016-02-03

One of the most abundant energy-dense storage compounds in eukaryotes are oils in the form of triacylglycerols , and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Moreover, plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerolsmore » as a renewable and sustainable bioenergy source. We review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals.« less

Triacylglycerol Metabolism, Function, and Accumulation in Plant Vegetative Tissues.

PubMed

Xu, Changcheng; Shanklin, John

2016-04-29

Oils in the form of triacylglycerols are the most abundant energy-dense storage compounds in eukaryotes, and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerols as a renewable and sustainable bioenergy source. Here, we review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals.

Plants for space plantations. [crops for closed life support systems

NASA Technical Reports Server (NTRS)

Nikishanova, T. I.

1978-01-01

Criteria for selection of candidate crops for closed life support systems are presented and discussed, and desired characteristics of candidate higher plant crops are given. Carbohydrate crops, which are most suitable, grown worldwide are listed and discussed. The sweet potato, ipomoea batatas Poir., is shown to meet the criteria to the greatest degree, and the criteria are recommended as suitable for initial evaluation of candidate higher plant crops for such systems.

Improving barley culm robustness for secured crop yield in a changing climate.

PubMed

Dockter, Christoph; Hansson, Mats

2015-06-01

The Green Revolution combined advancements in breeding and agricultural practice, and provided food security to millions of people. Daily food supply is still a major issue in many parts of the world and is further challenged by future climate change. Fortunately, life science research is currently making huge progress, and the development of future crop plants will be explored. Today, plant breeding typically follows one gene per trait. However, new scientific achievements have revealed that many of these traits depend on different genes and complex interactions of proteins reacting to various external stimuli. These findings open up new possibilities for breeding where variations in several genes can be combined to enhance productivity and quality. In this review we present an overview of genes determining plant architecture in barley, with a special focus on culm length. Many genes are currently known only through their mutant phenotypes, but emerging genomic sequence information will accelerate their identification. More than 1000 different short-culm barley mutants have been isolated and classified in different phenotypic groups according to culm length and additional pleiotropic characters. Some mutants have been connected to deficiencies in biosynthesis and reception of brassinosteroids and gibberellic acids. Still other mutants are unlikely to be connected to these hormones. The genes and corresponding mutations are of potential interest for development of stiff-straw crop plants tolerant to lodging, which occurs in extreme weather conditions with strong winds and heavy precipitation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Advancing Crop Transformation in the Era of Genome Editing.

PubMed

Altpeter, Fredy; Springer, Nathan M; Bartley, Laura E; Blechl, Ann E; Brutnell, Thomas P; Citovsky, Vitaly; Conrad, Liza J; Gelvin, Stanton B; Jackson, David P; Kausch, Albert P; Lemaux, Peggy G; Medford, June I; Orozco-Cárdenas, Martha L; Tricoli, David M; Van Eck, Joyce; Voytas, Daniel F; Walbot, Virginia; Wang, Kan; Zhang, Zhanyuan J; Stewart, C Neal

2016-07-01

Plant transformation has enabled fundamental insights into plant biology and revolutionized commercial agriculture. Unfortunately, for most crops, transformation and regeneration remain arduous even after more than 30 years of technological advances. Genome editing provides novel opportunities to enhance crop productivity but relies on genetic transformation and plant regeneration, which are bottlenecks in the process. Here, we review the state of plant transformation and point to innovations needed to enable genome editing in crops. Plant tissue culture methods need optimization and simplification for efficiency and minimization of time in culture. Currently, specialized facilities exist for crop transformation. Single-cell and robotic techniques should be developed for high-throughput genomic screens. Plant genes involved in developmental reprogramming, wound response, and/or homologous recombination should be used to boost the recovery of transformed plants. Engineering universal Agrobacterium tumefaciens strains and recruiting other microbes, such as Ensifer or Rhizobium, could facilitate delivery of DNA and proteins into plant cells. Synthetic biology should be employed for de novo design of transformation systems. Genome editing is a potential game-changer in crop genetics when plant transformation systems are optimized. © 2016 American Society of Plant Biologists. All rights reserved.

Genotypically Identifying Wheat Mesophyll Conductance Regulation under Progressive Drought Stress

PubMed Central

Olsovska, Katarina; Kovar, Marek; Brestic, Marian; Zivcak, Marek; Slamka, Pavol; Shao, Hong Bo

2016-01-01

Photosynthesis limitation by CO2 flow constraints from sub-stomatal cavities to carboxylation sites in chloroplasts under drought stress conditions is, at least in some plant species or crops not fully understood, yet. Leaf mesophyll conductance for CO2 (gm) may considerably affect both photosynthesis and water use efficiency (WUE) in plants under drought conditions. The aim of our study was to detect the responses of gm in leaves of four winter wheat (Triticum aestivum L.) genotypes from different origins under long-term progressive drought. Based on the measurement of gas-exchange parameters the variability of genotypic responses was analyzed at stomatal (stomata closure) and non-stomatal (diffusional and biochemical) limits of net CO2 assimilation rate (AN). In general, progressive drought caused an increasing leaf diffusion resistance against CO2 flow leading to the decrease of AN, gm and stomatal conductance (gs), respectively. Reduction of gm also led to inhibition of carboxylation efficiency (Vcmax). On the basis of achieved results a strong positive relationship between gm and gs was found out indicating a co-regulation and mutual independence of the relationship under the drought conditions. In severely stressed plants, the stomatal limitation of the CO2 assimilation rate was progressively increased, but to a less extent in comparison to gm, while a non-stomatal limitation became more dominant due to the prolonged drought. Mesophyll conductance (gm) seems to be a suitable mechanism and parameter for selection of improved diffusional properties and photosynthetic carbon assimilation in C3 plants, thus explaining their better photosynthetic performance at a whole plant level during periods of drought. PMID:27551283

Pathogen profile update: Fusarium oxysporum.

PubMed

Michielse, Caroline B; Rep, Martijn

2009-05-01

Kingdom Fungi; Phylum Ascomycota; Class Sordariomycetes; Order Hypocreales; Family Nectriaceae; genus Fusarium. Very broad at the species level. More than 120 different formae speciales have been identified based on specificity to host species belonging to a wide range of plant families. Initial symptoms of vascular wilt include vein clearing and leaf epinasty, followed by stunting, yellowing of the lower leaves, progressive wilting, defoliation and, finally, death of the plant. On fungal colonization, the vascular tissue turns brown, which is clearly visible in cross-sections of the stem. Some formae speciales are not primarily vascular pathogens, but cause foot and root rot or bulb rot. Can cause severe losses in many vegetables and flowers, field crops, such as cotton, and plantation crops, such as banana, date palm and oil palm. Use of resistant varieties is the only practical measure for controlling the disease in the field. In glasshouses, soil sterilization can be performed. http://www.broad.mit.edu/annotation/genome/fusarium_group/MultiHome.html; http://www.fgsc.net/Fusarium/fushome.htm; http://www.phi-base.org/query.php

Regression model estimation of early season crop proportions: North Dakota, some preliminary results

NASA Technical Reports Server (NTRS)

Lin, K. K. (Principal Investigator)

1982-01-01

To estimate crop proportions early in the season, an approach is proposed based on: use of a regression-based prediction equation to obtain an a priori estimate for specific major crop groups; modification of this estimate using current-year LANDSAT and weather data; and a breakdown of the major crop groups into specific crops by regression models. Results from the development and evaluation of appropriate regression models for the first portion of the proposed approach are presented. The results show that the model predicts 1980 crop proportions very well at both county and crop reporting district levels. In terms of planted acreage, the model underpredicted 9.1 percent of the 1980 published data on planted acreage at the county level. It predicted almost exactly the 1980 published data on planted acreage at the crop reporting district level and overpredicted the planted acreage by just 0.92 percent.

Measurement of physiological traits of paddy rice in temperature gradient chamber using Normalized Difference Vegetation Index and Photochemical Reflectance Index

NASA Astrophysics Data System (ADS)

Ryu, J. H.; Oh, D.; Cho, J.

2017-12-01

Global warming has been affecting the phenological and physiological conditions of crop plants due to heat stress. Thus, the scientific understanding of not only crop-yield change, but also growth progress during high temperature condition is necessary. In this study, growth response and yield of paddy rice depending on air temperature (Ta) has been studied in a Temperature Gradient Chamber (TGC) that is composed of higher Ta than actual Ta (ambient temperature). The results on imitating experiment of global warming provided the reduced production of crop by heat stress. Therefore, it is important to quickly detect the condition of a plant in order to minimize damage to heat stress on global warming. Phenological and physiological changes depending on Ta was detected using optical spectroscopy sensors because remote sensing is useful and efficient technology to monitor quickly and continually. Two vegetation indices, Normalized Difference Vegetation Index (NDVI) and Photochemical Reflectance Index (PRI), were applied to monitor paddy rice growth using hyperspectral and multispectral radiometer. Ta in TGC was gradually set from actual Ta + 0 ° to actual Ta + 3 °. The variations of NDVI and PRI were different during rice growth period, and also these patterns were changed depending on Ta condition. NDVI and PRI under +3 ° condition increase faster than ambient temperature. After heading stage, the values of NDVI and PRI were dropped. However, the NDVI and PRI of rice under heat stress were relatively slowly decreased. In addition, we found that the yield of rice decreased in the case of delayed drop patterns of NDVI and PRI after heading stage. Our results will be useful to understand crop plant conditions using vegetation index under global warming situations.

Leaf wetness distribution within a potato crop

NASA Astrophysics Data System (ADS)

Heusinkveld, B. G.

2010-07-01

The Netherlands has a mild maritime climate and therefore the major interest in leaf wetness is associated with foliar plant diseases. During moist micrometeorological conditions (i.e. dew, fog, rain), foliar fungal diseases may develop quickly and thereby destroy a crop quickly. Potato crop monocultures covering several hectares are especially vulnerable to such diseases. Therefore understanding and predicting leaf wetness in potato crops is crucial in crop disease control strategies. A field experiment was carried out in a large homogeneous potato crop in the Netherlands during the growing season of 2008. Two innovative sensor networks were installed as a 3 by 3 grid at 3 heights covering an area of about 2 hectares within two larger potato crops. One crop was located on a sandy soil and one crop on a sandy peat soil. In most cases leaf wetting starts in the top layer and then progresses downward. Leaf drying takes place in the same order after sunrise. A canopy dew simulation model was applied to simulate spatial leaf wetness distribution. The dew model is based on an energy balance model. The model can be run using information on the above-canopy wind speed, air temperature, humidity, net radiation and within canopy air temperature, humidity and soil moisture content and temperature conditions. Rainfall was accounted for by applying an interception model. The results of the dew model agreed well with the leaf wetness sensors if all local conditions were considered. The measurements show that the spatial correlation of leaf wetness decreases downward.

Effects of crop residues of sunflower (Helianthus annuus), maize (Zea mays L.) and soybean (Glycine max) on growth and seed yields of sunflower.

PubMed

Srisa-Ard, K

2007-04-15

This pot experiment was carried out at Suranaree Technology University Experimental Farm, Northeast Thailand to investigate effects of crop residues of sunflower, maize and soybean on total dry weight, top dry weight, plant height, root dry weight and seed yield of sunflower plants with the use of Korat soil series (Oxic Paleustults) during the rainy season (July-October) of the 2001. The experiment was laid in a split plot arranged in a Completely Randomized Design (CRD) with four replications where the crop residues of maize, sunflower and soybean were used as main plots. Whilst crop residues of roots, top growth and roots+top growth were used as subplots. The results showed that crop residues derived from roots of both sunflower and soybean plants had their significant inhibition effects of allelopathic substances on plant height, root dry weight, top growth dry weight and total dry weight plant(-1) of the sunflower plants than those derived from top growth of both crops alone (sunflower and soybean). Maize plant residues had no significant inhibition effect on growth of subsequent crop of sunflower.

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

NASA Astrophysics Data System (ADS)

Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.

2013-11-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991-2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha-1, but it decreased to 4.6-10.1 kg ha-1 with winter cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha-1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implement of winter cover crop programs, in part by helping to target critical pollution source areas for winter cover crop implementation.

Multiple Models for Rosaceae Genomics[OA

PubMed Central

Shulaev, Vladimir; Korban, Schuyler S.; Sosinski, Bryon; Abbott, Albert G.; Aldwinckle, Herb S.; Folta, Kevin M.; Iezzoni, Amy; Main, Dorrie; Arús, Pere; Dandekar, Abhaya M.; Lewers, Kim; Brown, Susan K.; Davis, Thomas M.; Gardiner, Susan E.; Potter, Daniel; Veilleux, Richard E.

2008-01-01

The plant family Rosaceae consists of over 100 genera and 3,000 species that include many important fruit, nut, ornamental, and wood crops. Members of this family provide high-value nutritional foods and contribute desirable aesthetic and industrial products. Most rosaceous crops have been enhanced by human intervention through sexual hybridization, asexual propagation, and genetic improvement since ancient times, 4,000 to 5,000 B.C. Modern breeding programs have contributed to the selection and release of numerous cultivars having significant economic impact on the U.S. and world markets. In recent years, the Rosaceae community, both in the United States and internationally, has benefited from newfound organization and collaboration that have hastened progress in developing genetic and genomic resources for representative crops such as apple (Malus spp.), peach (Prunus spp.), and strawberry (Fragaria spp.). These resources, including expressed sequence tags, bacterial artificial chromosome libraries, physical and genetic maps, and molecular markers, combined with genetic transformation protocols and bioinformatics tools, have rendered various rosaceous crops highly amenable to comparative and functional genomics studies. This report serves as a synopsis of the resources and initiatives of the Rosaceae community, recent developments in Rosaceae genomics, and plans to apply newly accumulated knowledge and resources toward breeding and crop improvement. PMID:18487361

G Quadruplex in Plants: A Ubiquitous Regulatory Element and Its Biological Relevance.

PubMed

Yadav, Vikas; Hemansi; Kim, Nayun; Tuteja, Narendra; Yadav, Puja

2017-01-01

G quadruplexes (G4) are higher-order DNA and RNA secondary structures formed by G-rich sequences that are built around tetrads of hydrogen-bonded guanine bases. Potential G4 quadruplex sequences have been identified in G-rich eukaryotic non-telomeric and telomeric genomic regions. Upon function, G4 formation is known to involve in chromatin remodeling, gene regulation and has been associated with genomic instability, genetic diseases and cancer progression. The natural role and biological validation of G4 structures is starting to be explored, and is of particular interest for the therapeutic interventions for human diseases. However, the existence and physiological role of G4 DNA and G4 RNA in plants species have not been much investigated yet and therefore, is of great interest for the development of improved crop varieties for sustainable agriculture. In this context, several recent studies suggests that these highly diverse G4 structures in plants can be employed to regulate expression of genes involved in several pathophysiological conditions including stress response to biotic and abiotic stresses as well as DNA damage. In the current review, we summarize the recent findings regarding the emerging functional significance of G4 structures in plants and discuss their potential value in the development of improved crop varieties.

Remotely sensing wheat maturation with radar

NASA Technical Reports Server (NTRS)

Bush, T. F.; Ulaby, F. T.

1975-01-01

The scattering properties of wheat were studied in the 8-18 GHz band as a function of frequency, polarization, incidence angle, and crop maturity. Supporting ground truth was collected at the time of measurement. The data indicate that the radar backscattering coefficient is sensitive to both radar system parameters and crop characteristics particularly at incidence angles near nadir. Linear regression analyses of the radar backscattering coefficient on both time and plant moisture content result in rather good correlation. Furthermore, by calculating the average time rate of change of the radar backscattering coefficient it is found that it undergoes rapid variations shortly before and after the wheat is harvested. Both of these analyses suggest methods for estimating wheat maturity and for monitoring the progress of harvest.

Current progress in orchid flowering/flower development research

PubMed Central

Wang, Hsin-Mei; Tong, Chii-Gong

2017-01-01

ABSTRACT Genetic pathways relevant to flowering of Arabidopsis are under the control of environmental cues such as day length and temperatures, and endogenous signals including phytohormones and developmental aging. However, genes and even regulatory pathways for flowering identified in crops show divergence from those of Arabidopsis and often do not have functional equivalents to Arabidopsis and/or existing species- or genus-specific regulators and show modified or novel pathways. Orchids are the largest, most highly evolved flowering plants, and form an extremely peculiar group of plants. Here, we briefly summarize the flowering pathways of Arabidopsis, rice and wheat and present them alongside recent discoveries/progress in orchid flowering and flower developmental processes including our transgenic Phalaenopsis orchids for LEAFY overexpression. Potential biotechnological applications in flowering/flower development of orchids with potential target genes are also discussed from an interactional and/or comparative viewpoint. PMID:28448202

DETERMINING POTENTIAL RISK TO NATIVE PLANTS FROM HERBICIDE DRIFT: COMPARATIVE RESPONSE OF SELECTED CROP AND NATIVE PLANT SPECIES TO GLYPHOSATE AND SULFOMETURON

EPA Science Inventory

abstract/abstract

While native plant communities may be at risk from herbicide use, current crop-centric test procedures for pesticide registration may not adequately represent the sensitivity of native non-crop plants to herbicides. We are designing a protocol to determi...

Genetic resources offer efficient tools for rice functional genomics research.

PubMed

Lo, Shuen-Fang; Fan, Ming-Jen; Hsing, Yue-Ie; Chen, Liang-Jwu; Chen, Shu; Wen, Ien-Chie; Liu, Yi-Lun; Chen, Ku-Ting; Jiang, Mirng-Jier; Lin, Ming-Kuang; Rao, Meng-Yen; Yu, Lin-Chih; Ho, Tuan-Hua David; Yu, Su-May

2016-05-01

Rice is an important crop and major model plant for monocot functional genomics studies. With the establishment of various genetic resources for rice genomics, the next challenge is to systematically assign functions to predicted genes in the rice genome. Compared with the robustness of genome sequencing and bioinformatics techniques, progress in understanding the function of rice genes has lagged, hampering the utilization of rice genes for cereal crop improvement. The use of transfer DNA (T-DNA) insertional mutagenesis offers the advantage of uniform distribution throughout the rice genome, but preferentially in gene-rich regions, resulting in direct gene knockout or activation of genes within 20-30 kb up- and downstream of the T-DNA insertion site and high gene tagging efficiency. Here, we summarize the recent progress in functional genomics using the T-DNA-tagged rice mutant population. We also discuss important features of T-DNA activation- and knockout-tagging and promoter-trapping of the rice genome in relation to mutant and candidate gene characterizations and how to more efficiently utilize rice mutant populations and datasets for high-throughput functional genomics and phenomics studies by forward and reverse genetics approaches. These studies may facilitate the translation of rice functional genomics research to improvements of rice and other cereal crops. © 2015 John Wiley & Sons Ltd.

DNA-informed breeding of rosaceous crops: promises, progress and prospects

PubMed Central

Peace, Cameron P

2017-01-01

Crops of the Rosaceae family provide valuable contributions to rural economies and human health and enjoyment. Sustained solutions to production challenges and market demands can be met with genetically improved new cultivars. Traditional rosaceous crop breeding is expensive and time-consuming and would benefit from improvements in efficiency and accuracy. Use of DNA information is becoming conventional in rosaceous crop breeding, contributing to many decisions and operations, but only after past decades of solved challenges and generation of sufficient resources. Successes in deployment of DNA-based knowledge and tools have arisen when the ‘chasm’ between genomics discoveries and practical application is bridged systematically. Key steps are establishing breeder desire for use of DNA information, adapting tools to local breeding utility, identifying efficient application schemes, accessing effective services in DNA-based diagnostics and gaining experience in integrating DNA information into breeding operations and decisions. DNA-informed germplasm characterization for revealing identity and relatedness has benefitted many programs and provides a compelling entry point to reaping benefits of genomics research. DNA-informed germplasm evaluation for predicting trait performance has enabled effective reallocation of breeding resources when applied in pioneering programs. DNA-based diagnostics is now expanding from specific loci to genome-wide considerations. Realizing the full potential of this expansion will require improved accuracy of predictions, multi-trait DNA profiling capabilities, streamlined breeding information management systems, strategies that overcome plant-based features that limit breeding progress and widespread training of current and future breeding personnel and allied scientists. PMID:28326185

Applying remote sensing expertise to crop improvement: progress and challenges to scale up high throughput field phenotyping from research to industry

NASA Astrophysics Data System (ADS)

Gouache, David; Beauchêne, Katia; Mini, Agathe; Fournier, Antoine; de Solan, Benoit; Baret, Fred; Comar, Alexis

2016-05-01

Digital and image analysis technologies in greenhouses have become commonplace in plant science research and started to move into the plant breeding industry. However, the core of plant breeding work takes place in fields. We will present successive technological developments that have allowed the migration and application of remote sensing approaches at large into the field of crop genetics and physiology research, with a number of projects that have taken place in France. These projects have allowed us to develop combined sensor plus vector systems, from tractor mounted and UAV (unmanned aerial vehicle) mounted spectroradiometry to autonomous vehicle mounted spectroradiometry, RGB (red-green-blue) imagery and Lidar. We have tested these systems for deciphering the genetics of complex plant improvement targets such as the robustness to nitrogen and water deficiency of wheat and maize. Our results from wheat experiments indicate that these systems can be used both to screen genetic diversity for nitrogen stress tolerance and to decipher the genetics behind this diversity. We will present our view on the next critical steps in terms of technology and data analysis that will be required to reach cost effective implementation in industrial plant breeding programs. If this can be achieved, these technologies will largely contribute to resolving the equation of increasing food supply in the resource limited world that lies ahead.

Glyphosate Effects on Plant Mineral Nutrition, Crop Rhizosphere Microbiota, and Plant Disease in Glyphosate-Resistant Crops

PubMed Central

2012-01-01

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the literature indicates that mineral nutrition in GR crops is not affected by either the GR trait or by application of glyphosate; (2) most of the available data support the view that neither the GR transgenes nor glyphosate use in GR crops increases crop disease; and (3) yield data on GR crops do not support the hypotheses that there are substantive mineral nutrition or disease problems that are specific to GR crops. PMID:23013354

[Research progress on mutation by spaceflight in medicinal plants breeding].

PubMed

Yan, Shuo; Gao, Wenyuan; Lu, Fuping; Zhao, Runhuai

2010-02-01

Space breeding in medicinal plants is special characteristics in China. Compared with other plants, in spite of a relatively small number, Medicinal plants have more obvious characteristics and advantages. Research on medicinal plants has also been carried into all aspects, such as biological traits, physiology and biochemistry, genomics, as well as differences in chemical composition, and chemical composition analysis is also involved. However, compared with other plants, especially crops and vegetables, biological research is an obvious deficiency, that is mainly reflected in the insufficient genetics and breeding researches, the stability of genetic traits from generation to generation were not followed up and in-depth study in breeding areas was not carried out. If medicinal plants resources from space with the genetic stability good quality were selected, it would address the problem of lack of resources and ease the pressure on wild resources of medicinal plants. It would at the same time play an important role in promoting the development of medicinal botany space breeding and the implementation of modernization of traditional Chinese medicine.

Bacteriophages and Bacterial Plant Diseases

PubMed Central

Buttimer, Colin; McAuliffe, Olivia; Ross, R. P.; Hill, Colin; O’Mahony, Jim; Coffey, Aidan

2017-01-01

Losses in crop yields due to disease need to be reduced in order to meet increasing global food demands associated with growth in the human population. There is a well-recognized need to develop new environmentally friendly control strategies to combat bacterial crop disease. Current control measures involving the use of traditional chemicals or antibiotics are losing their efficacy due to the natural development of bacterial resistance to these agents. In addition, there is an increasing awareness that their use is environmentally unfriendly. Bacteriophages, the viruses of bacteria, have received increased research interest in recent years as a realistic environmentally friendly means of controlling bacterial diseases. Their use presents a viable control measure for a number of destructive bacterial crop diseases, with some phage-based products already becoming available on the market. Phage biocontrol possesses advantages over chemical controls in that tailor-made phage cocktails can be adapted to target specific disease-causing bacteria. Unlike chemical control measures, phage mixtures can be easily adapted for bacterial resistance which may develop over time. In this review, we will examine the progress and challenges for phage-based disease biocontrol in food crops. PMID:28163700

Transgenic Strategies for Enhancement of Nematode Resistance in Plants

PubMed Central

Ali, Muhammad A.; Azeem, Farrukh; Abbas, Amjad; Joyia, Faiz A.; Li, Hongjie; Dababat, Abdelfattah A.

2017-01-01

Plant parasitic nematodes (PPNs) are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants. PMID:28536595

Transgenic Strategies for Enhancement of Nematode Resistance in Plants.

PubMed

Ali, Muhammad A; Azeem, Farrukh; Abbas, Amjad; Joyia, Faiz A; Li, Hongjie; Dababat, Abdelfattah A

2017-01-01

Plant parasitic nematodes (PPNs) are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants.

Recombinant protease inhibitors for herbivore pest control: a multitrophic perspective.

PubMed

Schlüter, Urte; Benchabane, Meriem; Munger, Aurélie; Kiggundu, Andrew; Vorster, Juan; Goulet, Marie-Claire; Cloutier, Conrad; Michaud, Dominique

2010-10-01

Protease inhibitors are a promising complement to Bt toxins for the development of insect-resistant transgenic crops, but their limited specificity against proteolytic enzymes and the ubiquity of protease-dependent processes in living organisms raise questions about their eventual non-target effects in agroecosystems. After a brief overview of the main factors driving the impacts of insect-resistant transgenic crops on non-target organisms, the possible effects of protease inhibitors are discussed from a multitrophic perspective, taking into account not only the target herbivore proteases but also the proteases of other organisms found along the trophic chain, including the plant itself. Major progress has been achieved in recent years towards the design of highly potent broad-spectrum inhibitors and the field deployment of protease inhibitor-expressing transgenic plants resistant to major herbivore pests. A thorough assessment of the current literature suggests that, whereas the non-specific inhibitory effects of recombinant protease inhibitors in plant food webs could often be negligible and their 'unintended' pleiotropic effects in planta of potential agronomic value, the innocuity of these proteins might always remain an issue to be assessed empirically, on a case-by-case basis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Changcheng; Shanklin, John

One of the most abundant energy-dense storage compounds in eukaryotes are oils in the form of triacylglycerols , and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Moreover, plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerolsmore » as a renewable and sustainable bioenergy source. We review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals.« less

Aggressiveness Changes in Populations of Didymella pinodes over Winter and Spring Pea Cropping Seasons

PubMed Central

Laloi, G.; Montarry, J.; Guibert, M.; Andrivon, D.; Michot, D.

2016-01-01

ABSTRACT Ascochyta blight, caused by the necrotrophic ascomycete Didymella pinodes, is responsible for severe losses in winter and spring pea crops. Despite different climatic conditions, epidemics on winter and spring crops are due to a single population of D. pinodes, suggesting gene flow either between the two crops or from reservoir sources during the cropping season. This should lead to similar pathogenicity characteristics in isolates sampled from the two crops. However, these hypotheses have never been formally tested. We therefore sampled a total of 520 D. pinodes strains throughout a growing season from winter and spring pea plots (WP and SP, respectively) and from winter and spring trap plants (TWP and TSP). Amplified fragment length polymorphism (AFLP) markers revealed high genetic diversity within subpopulations, whereas pathogenicity tests showed that mean aggressiveness increases over the course of an epidemic. These results support the idea that alloinoculum contributes to the carryover of epidemics between winter and spring crops and that the most aggressive isolates are selected as an epidemic progresses. IMPORTANCE Ascochyta blight, caused by Didymella pinodes, is responsible for severe losses in pea crops. While previous studies have shown that ascochyta blight epidemics on winter and spring crops are due to a single population of D. pinodes, suggesting that isolates from the two crops present similar pathogenicity characteristics, that hypothesis have never been tested. Genetic analysis of subpopulations sampled throughout a growing season from winter and spring pea plots revealed high genetic diversity within subpopulations, whereas pathogenicity tests showed that mean aggressiveness increases over the course of an epidemic. PMID:27208102

Fortifying Horticultural Crops with Essential Amino Acids: A Review.

PubMed

Wang, Guoping; Xu, Mengyun; Wang, Wenyi; Galili, Gad

2017-06-19

To feed the world's growing population, increasing the yield of crops is not the only important factor, improving crop quality is also important, and it presents a significant challenge. Among the important crops, horticultural crops (particularly fruits and vegetables) provide numerous health compounds, such as vitamins, antioxidants, and amino acids. Essential amino acids are those that cannot be produced by the organism and, therefore, must be obtained from diet, particularly from meat, eggs, and milk, as well as a variety of plants. Extensive efforts have been devoted to increasing the levels of essential amino acids in plants. Yet, these efforts have been met with very little success due to the limited genetic resources for plant breeding and because high essential amino acid content is generally accompanied by limited plant growth. With a deep understanding of the biosynthetic pathways of essential amino acids and their interactions with the regulatory networks in plants, it should be possible to use genetic engineering to improve the essential amino acid content of horticultural plants, rendering these plants more nutritionally favorable crops. In the present report, we describe the recent advances in the enhancement of essential amino acids in horticultural plants and possible future directions towards their bio-fortification.

Effect of winter cover crops on nematode population levels in north Florida.

PubMed

Wang, K-H; McSorley, R; Gallaher, R N

2004-12-01

Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativa), lupine (Lupinus angustifolius), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). At the end of the corn crop in year 1, population densities of Meloidogyne incognita were lowest on corn following rye or oat (P

Roguing with replacement in perennial crops: conditions for successful disease management.

PubMed

Sisterson, Mark S; Stenger, Drake C

2013-02-01

Replacement of diseased plants with healthy plants is commonly used to manage spread of plant pathogens in perennial cropping systems. This strategy has two potential benefits. First, removing infected plants may slow pathogen spread by eliminating inoculum sources. Second, replacing infected plants with uninfected plants may offset yield losses due to disease. The extent to which these benefits are realized depends on multiple factors. In this study, sensitivity analyses of two spatially explicit simulation models were used to evaluate how assumptions concerning implementation of a plant replacement program and pathogen spread interact to affect disease suppression. In conjunction, effects of assumptions concerning yield loss associated with disease and rates of plant maturity on yields were simultaneously evaluated. The first model was used to evaluate effects of plant replacement on pathogen spread and yield on a single farm, consisting of a perennial crop monoculture. The second model evaluated effects of plant replacement on pathogen spread and yield in a 100 farm crop growing region, with all farms maintaining a monoculture of the same perennial crop. Results indicated that efficient replacement of infected plants combined with a high degree of compliance among farms effectively slowed pathogen spread, resulting in replacement of few plants and high yields. In contrast, inefficient replacement of infected plants or limited compliance among farms failed to slow pathogen spread, resulting in replacement of large numbers of plants (on farms practicing replacement) with little yield benefit. Replacement of infected plants always increased yields relative to simulations without plant replacement provided that infected plants produced no useable yield. However, if infected plants produced useable yields, inefficient removal of infected plants resulted in lower yields relative to simulations without plant replacement for perennial crops with long maturation periods in some cases.

Induced Mutations for Improving Production on Bread and Durum Wheat

NASA Astrophysics Data System (ADS)

Stamo, Ilirjana; Ylli, Ariana; Dodbiba, Andon

2007-04-01

Wheat is a very important crop and has been bred for food and its improvement is continuous from cross-breeding. Radiation and chemically induced mutations have provided variability in selection for novel varieties. Four bread and one durum wheat cultivars were exposed to gamma rays, Cs 137 with doses 10, 15 and 20 krad (2000 seeds of each dose and cultivars). We have isolated mutant plants with height reduced and on cv Progress spike without chaff.

Induced Mutations for Improving Production on Bread and Durum Wheat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stamo, Ilirjana; Ylli, Ariana; Dodbiba, Andon

Wheat is a very important crop and has been bred for food and its improvement is continuous from cross-breeding. Radiation and chemically induced mutations have provided variability in selection for novel varieties. Four bread and one durum wheat cultivars were exposed to gamma rays, Cs 137 with doses 10, 15 and 20 krad (2000 seeds of each dose and cultivars). We have isolated mutant plants with height reduced and on cv Progress spike without chaff.

Genomic exploitation of genetic variation for crop improvement

USDA-ARS?s Scientific Manuscript database

Crop plants produce food, fiber, and fuel that are essential to human civilization and mainstays of economic prosperity. Our society continues to cultivate and improve the crop plants for better quality and productivity with sustainable environments. The process of crop genetic improvement has bee...

7 CFR 1437.201 - Prevented planting acreage.

Code of Federal Regulations, 2010 CFR

2010-01-01

... includes, but is not limited to: (1) Value-loss crops, including, but not limited to, Christmas trees, aquaculture, and ornamental nursery; (2) Tree crops and other perennials, unless: (i) The producer can prove resources unique to the planting of tree crops and other perennials were available to plant, grow, and...

Plant, soil, and shadow reflectance components of row crops

NASA Technical Reports Server (NTRS)

Richardson, A. J.; Wiegand, C. L.; Gausman, H. W.; Cuellar, J. A.; Gerbermann, A. H.

1975-01-01

Data from the first Earth Resource Technology Satellite (LANDSAT-1) multispectral scanner (MSS) were used to develop three plant canopy models (Kubelka-Munk (K-M), regression, and combined K-M and regression models) for extracting plant, soil, and shadow reflectance components of cropped fields. The combined model gave the best correlation between MSS data and ground truth, by accounting for essentially all of the reflectance of plants, soil, and shadow between crop rows. The principles presented can be used to better forecast crop yield and to estimate acreage.

Plant/soil concentration ratios for paired field and garden crops, with emphasis on iodine and the role of soil adhesion.

PubMed

Sheppard, S C; Long, J M; Sanipelli, B

2010-12-01

In the effort to predict the risks associated with contaminated soils, considerable reliance is placed on plant/soil concentration ratio (CR) values measured at sites other than the contaminated site. This inevitably results in the need to extrapolate among the many soil and plant types. There are few studies that compare CR among plant types that encompass both field and garden crops. Here, CRs for 40 elements were measured for 25 crops from farm and garden sites chosen so the grain crops were in close proximity to the gardens. Special emphasis was placed on iodine (I) because data for this element are sparse. For many elements, there were consistent trends among CRs for the various crop types, with leafy crops > root crops ≥ fruit crops ≈ seed crops. Exceptions included CR values for As, K, Se and Zn which were highest in the seed crops. The correlation of CRs from one plant type to another was evident only when there was a wide range in soil concentrations. In comparing CRs between crop types, it became apparent that the relationships differed for the rare earth elements (REE), which also had very low CR values. The CRs for root and leafy crops of REE converged to a minimum value. This was attributed to soil adhesion, despite the samples being washed, and the average soil adhesion for root crops was 500 mg soil kg⁻¹ dry plant and for leafy crops was 5 g kg⁻¹. Across elements, the log CR was negatively correlated with log Kd (the soil solid/liquid partition coefficient), as expected. Although, this correlation is expected, measures of correlation coefficients suitable for stochastic risk assessment are not frequently reported. The results suggest that r ≈ -0.7 would be appropriate for risk assessment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Do Refuge Plants Favour Natural Pest Control in Maize Crops?

PubMed Central

Quispe, Reinaldo; Mazón, Marina; Rodríguez-Berrío, Alexander

2017-01-01

The use of non-crop plants to provide the resources that herbivorous crop pests’ natural enemies need is being increasingly incorporated into integrated pest management programs. We evaluated insect functional groups found on three refuges consisting of five different plant species each, planted next to a maize crop in Lima, Peru, to investigate which refuge favoured natural control of herbivores considered as pests of maize in Peru, and which refuge plant traits were more attractive to those desirable enemies. Insects occurring in all the plants, including the maize crop itself, were sampled weekly during the crop growing cycle, from February to June 2011. All individuals collected were identified and classified into three functional groups: herbivores, parasitoids, and predators. Refuges were compared based on their effectiveness in enhancing the populations of predator and parasitoid insects of the crop enemies. Refuges A and B were the most effective, showing the highest richness and abundance of both predators and parasitoids, including several insect species that are reported to attack the main insect pests of maize (Spodoptera frugiperda and Rhopalosiphum maidis), as well as other species that serve as alternative hosts of these natural enemies. PMID:28718835

Auxin and the integration of environmental signals into plant root development

PubMed Central

Kazan, Kemal

2013-01-01

Background Auxin is a versatile plant hormone with important roles in many essential physiological processes. In recent years, significant progress has been made towards understanding the roles of this hormone in plant growth and development. Recent evidence also points to a less well-known but equally important role for auxin as a mediator of environmental adaptation in plants. Scope This review briefly discusses recent findings on how plants utilize auxin signalling and transport to modify their root system architecture when responding to diverse biotic and abiotic rhizosphere signals, including macro- and micro-nutrient starvation, cold and water stress, soil acidity, pathogenic and beneficial microbes, nematodes and neighbouring plants. Stress-responsive transcription factors and microRNAs that modulate auxin- and environment-mediated root development are also briefly highlighted. Conclusions The auxin pathway constitutes an essential component of the plant's biotic and abiotic stress tolerance mechanisms. Further understanding of the specific roles that auxin plays in environmental adaptation can ultimately lead to the development of crops better adapted to stressful environments. PMID:24136877

Auxin and the integration of environmental signals into plant root development.

PubMed

Kazan, Kemal

2013-12-01

Auxin is a versatile plant hormone with important roles in many essential physiological processes. In recent years, significant progress has been made towards understanding the roles of this hormone in plant growth and development. Recent evidence also points to a less well-known but equally important role for auxin as a mediator of environmental adaptation in plants. This review briefly discusses recent findings on how plants utilize auxin signalling and transport to modify their root system architecture when responding to diverse biotic and abiotic rhizosphere signals, including macro- and micro-nutrient starvation, cold and water stress, soil acidity, pathogenic and beneficial microbes, nematodes and neighbouring plants. Stress-responsive transcription factors and microRNAs that modulate auxin- and environment-mediated root development are also briefly highlighted. The auxin pathway constitutes an essential component of the plant's biotic and abiotic stress tolerance mechanisms. Further understanding of the specific roles that auxin plays in environmental adaptation can ultimately lead to the development of crops better adapted to stressful environments.

Functional diversification of the dehydrin gene family in apple and its contribution to cold acclimation during dormancy.

PubMed

Falavigna, Vítor da Silveira; Miotto, Yohanna Evelyn; Porto, Diogo Denardi; Anzanello, Rafael; Santos, Henrique Pessoa dos; Fialho, Flávio Bello; Margis-Pinheiro, Márcia; Pasquali, Giancarlo; Revers, Luís Fernando

2015-11-01

Dehydrins (DHN) are proteins involved in plant adaptive responses to abiotic stresses, mainly dehydration. Several studies in perennial crops have linked bud dormancy progression, a process characterized by the inability to initiate growth from meristems under favorable conditions, with DHN gene expression. However, an in-depth characterization of DHNs during bud dormancy progression is still missing. An extensive in silico characterization of the apple DHN gene family was performed. Additionally, we used five different experiments that generated samples with different dormancy status, including genotypes with contrasting dormancy traits, to analyze how DHN genes are being regulated during bud dormancy progression in apple by real-time quantitative polymerase chain reaction (RT-qPCR). Duplication events took place in the diversification of apple DHN family. Additionally, MdDHN genes presented tissue- and bud dormant-specific expression patterns. Our results indicate that MdDHN genes are highly divergent in function, with overlapping levels, and that their expressions are fine-tuned by the environment during the dormancy process in apple. © 2015 Scandinavian Plant Physiology Society.

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

USGS Publications Warehouse

Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.

2013-01-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implement of winter cover crop programs, in part by helping to target critical pollution source areas for winter cover crop implementation.

Reduce pests, enhance production: benefits of intercropping at high densities for okra farmers in Cameroon.

PubMed

Singh, Akanksha; Weisser, Wolfgang W; Hanna, Rachid; Houmgny, Raissa; Zytynska, Sharon E

2017-10-01

Intercropping can help reduce insect pest populations. However, the results of intercropping can be pest- and crop-species specific, with varying effects on crop yield, and pest suppression success. In Cameroon, okra vegetable is often grown in intercropped fields and sown with large distances between planting rows (∼ 2 m). Dominant okra pests include cotton aphids, leaf beetles and whiteflies. In a field experiment, we intercropped okra with maize and bean in different combinations (okra monoculture, okra-bean, okra-maize and okra-bean-maize) and altered plant densities (high and low) to test for the effects of diversity, crop identity and planting distances on okra pests, their predators and yield. We found crop identity and plant density, but not crop diversity to influence okra pests, their predators and okra yield. Only leaf beetles decreased okra yield and their abundance reduced at high plant density. Overall, okra grown with bean at high density was the most economically profitable combination. We suggest that when okra is grown at higher densities, legumes (e.g. beans) should be included as an additional crop. Intercropping with a leguminous crop can enhance nitrogen in the soil, benefiting other crops, while also being harvested and sold at market for additional profit. Manipulating planting distances and selecting plants based on their beneficial traits may thus help to eliminate yield gaps in sustainable agriculture. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Cover crop options and mixes for the upper midwest

USDA-ARS?s Scientific Manuscript database

The implementation of cover crops in Iowa has the potential to decrease soil erosion, weed populations, and the loss of nutrients. Currently, less than 1% of all Iowa farmland is planted to cover crops, most of which is winter rye. This research explores 16 different cover crop treatments planted a...

Perceptions of Crop Science Instructional Materials.

ERIC Educational Resources Information Center

Elkins, D. M.

1994-01-01

A number of crop science instructors have indicated that there is a shortage of quality, current crop/plant science teaching materials, particularly textbooks. A survey instrument was developed to solicit information from teachers about the use and adequacy of textbooks, laboratory manuals, and videotapes in crop/plant science instruction. (LZ)

7 CFR 1412.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... available, the planted acres as determined by CCC using other sources. Planted and considered planted (P&CP... the FSA county committee on the farm for a crop. For the purposes of this part, P&CP is limited to... sequence. Replacement crop acreage is not included as P&CP. Processing means with respect to uses of a crop...

7 CFR 1412.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... available, the planted acres as determined by CCC using other sources. Planted and considered planted (P&CP... the FSA county committee on the farm for a crop. For the purposes of this part P&CP is limited to... sequence. Replacement crop acreage is not included as P&CP. Processing means with respect to uses of a crop...

7 CFR 1412.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... available, the planted acres as determined by CCC using other sources. Planted and considered planted (P&CP... the FSA county committee on the farm for a crop. For the purposes of this part, P&CP is limited to... sequence. Replacement crop acreage is not included as P&CP. Processing means with respect to uses of a crop...

7 CFR 1412.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... available, the planted acres as determined by CCC using other sources. Planted and considered planted (P&CP... the FSA county committee on the farm for a crop. For the purposes of this part, P&CP is limited to... sequence. Replacement crop acreage is not included as P&CP. Processing means with respect to uses of a crop...

Recent advances towards development and commercialization of plant cell culture processes for synthesis of biomolecules

PubMed Central

Wilson, Sarah A.; Roberts, Susan C.

2011-01-01

(1) Summary Plant cell culture systems were initially explored for use in commercial synthesis of several high value secondary metabolites, allowing for sustainable production that was not limited by the low yields associated with natural harvest or the high cost associated with complex chemical synthesis. Although there have been some commercial successes, most notably paclitaxel production from Taxus sp., process limitations exist with regards to low product yields and inherent production variability. A variety of strategies are being developed to overcome these limitations including elicitation strategies, in situ product removal and metabolic engineering with single genes and transcription factors. Recently, the plant cell culture production platform has been extended to pharmaceutically active heterologous proteins. Plant systems are beneficial because they are able to produce complex proteins that are properly glycosylated, folded and assembled without the risk of contamination by toxins that are associated with mammalian or microbial production systems. Additionally, plant cell culture isolates transgenic material from the environment, allows for more controllable conditions over field grown crops and promotes secretion of proteins to the medium, reducing downstream purification costs. Despite these benefits, the increase in cost of heterologous protein synthesis in plant cell culture as opposed to field grown crops is significant and therefore processes must be optimized with regards to maximizing secretion and enhancing protein stability in the cell culture media. This review discusses recent advancements in plant cell culture processing technology, focusing on progress towards overcoming the problems associated with commercialization of these production systems and highlighting recent commercial successes. PMID:22059985

Manipulation of Metabolic Pathways to Develop Vitamin-Enriched Crops for Human Health

PubMed Central

Jiang, Ling; Wang, Weixuan; Lian, Tong; Zhang, Chunyi

2017-01-01

Vitamin deficiencies are major forms of micronutrient deficiencies, and are associated with huge economic losses as well as severe physical and intellectual damages to humans. Much evidence has demonstrated that biofortification plays an important role in combating vitamin deficiencies due to its economical and effective delivery of nutrients to populations in need. Biofortification enables food plants to be enriched with vitamins through conventional breeding and/or biotechnology. Here, we focus on the progress in the manipulation of the vitamin metabolism, an essential part of biofortification, by the genetic modification or by the marker-assisted selection to understand mechanisms underlying metabolic improvement in food plants. We also propose to integrate new breeding technologies with metabolic pathway modification to facilitate biofortification in food plants and, thereby, to benefit human health. PMID:28634484

Prioritizing stream types according to their potential risk to receive crop plant material--A GIS-based procedure to assist in the risk assessment of genetically modified crops and systemic insecticide residues.

PubMed

Bundschuh, Rebecca; Kuhn, Ulrike; Bundschuh, Mirco; Naegele, Caroline; Elsaesser, David; Schlechtriemen, Ulrich; Oehen, Bernadette; Hilbeck, Angelika; Otto, Mathias; Schulz, Ralf; Hofmann, Frieder

2016-03-15

Crop plant residues may enter aquatic ecosystems via wind deposition or surface runoff. In the case of genetically modified crops or crops treated with systemic pesticides, these materials may contain insecticidal Bt toxins or pesticides that potentially affect aquatic life. However, the particular exposure pattern of aquatic ecosystems (i.e., via plant material) is not properly reflected in current risk assessment schemes, which primarily focus on waterborne toxicity and not on plant material as the route of uptake. To assist in risk assessment, the present study proposes a prioritization procedure of stream types based on the freshwater network and crop-specific cultivation data using maize in Germany as a model system. To identify stream types with a high probability of receiving crop materials, we developed a formalized, criteria-based and thus transparent procedure that considers the exposure-related parameters, ecological status--an estimate of the diversity and potential vulnerability of local communities towards anthropogenic stress--and availability of uncontaminated reference sections. By applying the procedure to maize, ten stream types out of 38 are expected to be the most relevant if the ecological effects from plant-incorporated pesticides need to be evaluated. This information is an important first step to identifying habitats within these stream types with a high probability of receiving crop plant material at a more local scale, including accumulation areas. Moreover, the prioritization procedure developed in the present study may support the selection of aquatic species for ecotoxicological testing based on their probability of occurrence in stream types having a higher chance of exposure. Finally, this procedure can be adapted to any geographical region or crop of interest and is, therefore, a valuable tool for a site-specific risk assessment of crop plants carrying systemic pesticides or novel proteins, such as insecticidal Bt toxins, expressed in genetically modified crops. Copyright © 2015 Elsevier B.V. All rights reserved.

Single-tube hydroponics as a novel idea for small-scale production of crop seed in a plant incubator.

PubMed

Kuroda, Masaharu; Ikenaga, Sachiko

2015-01-01

We present a novel protocol for small-scale production of crop seed in a plant incubator termed "Single-tube hydroponics." Our protocol minimizes the materials and methods for cultivation whereby a large number of independent plants can be cultured in a limited space. This study may aid in the improvement of crop seed components, especially in the cultivation of transgenic plants.

Expansion of mass-flowering crops leads to transient pollinator dilution and reduced wild plant pollination

PubMed Central

Holzschuh, Andrea; Dormann, Carsten F.; Tscharntke, Teja; Steffan-Dewenter, Ingolf

2011-01-01

Agricultural land use results in direct biodiversity decline through loss of natural habitat, but may also cause indirect cross-habitat effects on conservation areas. We conducted three landscape-scale field studies on 67 sites to test the hypothesis that mass flowering of oilseed rape (Brassica napus) results in a transient dilution of bees in crop fields, and in increased competition between crop plants and grassland plants for pollinators. Abundances of bumble-bees, which are the main pollinators of the grassland plant Primula veris, but also pollinate oilseed rape (OSR), decreased with increasing amount of OSR. This landscape-scale dilution affected bumble-bee abundances strongly in OSR fields and marginally in grasslands, where bumble-bee abundances were generally low at the time of Primula flowering. Seed set of Primula veris, which flowers during OSR bloom, was reduced by 20 per cent when the amount of OSR within 1 km radius increased from 0 to 15 per cent. Hence, the current expansion of bee-attractive biofuel crops results in transient dilution of crop pollinators, which means an increased competition for pollinators between crops and wild plants. In conclusion, mass-flowering crops potentially threaten fitness of concurrently flowering wild plants in conservation areas, despite the fact that, in the long run, mass-flowering crops can enhance abundances of generalist pollinators and their pollination service. PMID:21471115

Exploring the limits of crop productivity: A model to evaluate progress

NASA Technical Reports Server (NTRS)

Bugbee, Bruce

1990-01-01

The goal was to determine the limits of crop productivity when all environmental constraints were removed. Researchers define productivity as food output per unit of input. Researchers evaluated cultivars of wheat with reduced leaf size and number to decrease the leaf area index at high plant densities. These cultivars may also have an improved harvest index. Hydroponic studies indicate that 1 mM nitrate in solution is adequate to support maximum growth in these systems, provided iron nutrition is adequate. Wheat does not accumulate nitrate in leaves even when the solution nitrate concentration is 15 mM. Long-term photosynthetic efficiency (g mol (exp -1) of photons) and harvest index were not altered by photoperiod (16, 20, or 24 hours). Wheat does not need, nor benefit from, a diurnal dark period.

7 CFR 457.101 - Small grains crop insurance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... into an established grass or legume; or (iii) Planted as a nurse crop, unless planted as a nurse crop... measures; (e) Wildlife; (f) Earthquake; (g) Volcanic eruption; (h) Failure of the irrigation water supply...

7 CFR 457.101 - Small grains crop insurance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... into an established grass or legume; or (iii) Planted as a nurse crop, unless planted as a nurse crop... application of disease control measures; (e) Wildlife; (f) Earthquake; (g) Volcanic eruption; or (h) Failure...

The potential of plant microbiota in reducing postharvest food loss.

PubMed

Buchholz, Franziska; Kostić, Tanja; Sessitsch, Angela; Mitter, Birgit

2018-03-26

The role of the plant microbiota in plant establishment, growth and health is well studied, but the dynamics of postharvest crop microbiota and its role in postharvest crop quality are largely unexplored, although food loss is an enormous issue worldwide. The microbiota might be especially important during crop storage by either preventing or favouring rots, or quality loss due to, for example, sprouting, saccharification, water loss or spoilage. We need more research on plant-microbe interactions in postharvest crops to be in future able to provide microbial solutions for plant production along the whole food chain from field to fork. © 2018 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Crops In Silico: Generating Virtual Crops Using an Integrative and Multi-scale Modeling Platform.

PubMed

Marshall-Colon, Amy; Long, Stephen P; Allen, Douglas K; Allen, Gabrielle; Beard, Daniel A; Benes, Bedrich; von Caemmerer, Susanne; Christensen, A J; Cox, Donna J; Hart, John C; Hirst, Peter M; Kannan, Kavya; Katz, Daniel S; Lynch, Jonathan P; Millar, Andrew J; Panneerselvam, Balaji; Price, Nathan D; Prusinkiewicz, Przemyslaw; Raila, David; Shekar, Rachel G; Shrivastava, Stuti; Shukla, Diwakar; Srinivasan, Venkatraman; Stitt, Mark; Turk, Matthew J; Voit, Eberhard O; Wang, Yu; Yin, Xinyou; Zhu, Xin-Guang

2017-01-01

Multi-scale models can facilitate whole plant simulations by linking gene networks, protein synthesis, metabolic pathways, physiology, and growth. Whole plant models can be further integrated with ecosystem, weather, and climate models to predict how various interactions respond to environmental perturbations. These models have the potential to fill in missing mechanistic details and generate new hypotheses to prioritize directed engineering efforts. Outcomes will potentially accelerate improvement of crop yield, sustainability, and increase future food security. It is time for a paradigm shift in plant modeling, from largely isolated efforts to a connected community that takes advantage of advances in high performance computing and mechanistic understanding of plant processes. Tools for guiding future crop breeding and engineering, understanding the implications of discoveries at the molecular level for whole plant behavior, and improved prediction of plant and ecosystem responses to the environment are urgently needed. The purpose of this perspective is to introduce Crops in silico (cropsinsilico.org), an integrative and multi-scale modeling platform, as one solution that combines isolated modeling efforts toward the generation of virtual crops, which is open and accessible to the entire plant biology community. The major challenges involved both in the development and deployment of a shared, multi-scale modeling platform, which are summarized in this prospectus, were recently identified during the first Crops in silico Symposium and Workshop.

Crops In Silico: Generating Virtual Crops Using an Integrative and Multi-scale Modeling Platform

PubMed Central

Marshall-Colon, Amy; Long, Stephen P.; Allen, Douglas K.; Allen, Gabrielle; Beard, Daniel A.; Benes, Bedrich; von Caemmerer, Susanne; Christensen, A. J.; Cox, Donna J.; Hart, John C.; Hirst, Peter M.; Kannan, Kavya; Katz, Daniel S.; Lynch, Jonathan P.; Millar, Andrew J.; Panneerselvam, Balaji; Price, Nathan D.; Prusinkiewicz, Przemyslaw; Raila, David; Shekar, Rachel G.; Shrivastava, Stuti; Shukla, Diwakar; Srinivasan, Venkatraman; Stitt, Mark; Turk, Matthew J.; Voit, Eberhard O.; Wang, Yu; Yin, Xinyou; Zhu, Xin-Guang

2017-01-01

Multi-scale models can facilitate whole plant simulations by linking gene networks, protein synthesis, metabolic pathways, physiology, and growth. Whole plant models can be further integrated with ecosystem, weather, and climate models to predict how various interactions respond to environmental perturbations. These models have the potential to fill in missing mechanistic details and generate new hypotheses to prioritize directed engineering efforts. Outcomes will potentially accelerate improvement of crop yield, sustainability, and increase future food security. It is time for a paradigm shift in plant modeling, from largely isolated efforts to a connected community that takes advantage of advances in high performance computing and mechanistic understanding of plant processes. Tools for guiding future crop breeding and engineering, understanding the implications of discoveries at the molecular level for whole plant behavior, and improved prediction of plant and ecosystem responses to the environment are urgently needed. The purpose of this perspective is to introduce Crops in silico (cropsinsilico.org), an integrative and multi-scale modeling platform, as one solution that combines isolated modeling efforts toward the generation of virtual crops, which is open and accessible to the entire plant biology community. The major challenges involved both in the development and deployment of a shared, multi-scale modeling platform, which are summarized in this prospectus, were recently identified during the first Crops in silico Symposium and Workshop. PMID:28555150

Progress in modelling agricultural impacts of and adaptations to climate change.

PubMed

Rötter, R P; Hoffmann, M P; Koch, M; Müller, C

2018-06-01

Modelling is a key tool to explore agricultural impacts of and adaptations to climate change. Here we report recent progress made especially referring to the large project initiatives MACSUR and AgMIP; in particular, in modelling potential crop impacts from field to global using multi-model ensembles. We identify two main fields where further progress is necessary: a more mechanistic understanding of climate impacts and management options for adaptation and mitigation; and focusing on cropping systems and integrative multi-scale assessments instead of single season and crops, especially in complex tropical and neglected but important cropping systems. Stronger linking of experimentation with statistical and eco-physiological crop modelling could facilitate the necessary methodological advances. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

NASA Astrophysics Data System (ADS)

Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.

2014-12-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality at the watershed scale (~ 50 km2) and to identify critical source areas of high nitrate export. A physically based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data to simulate hydrological processes and agricultural nutrient cycling over the period of 1990-2000. To accurately simulate winter cover crop biomass in relation to growing conditions, a new approach was developed to further calibrate plant growth parameters that control the leaf area development curve using multitemporal satellite-based measurements of species-specific winter cover crop performance. Multiple SWAT scenarios were developed to obtain baseline information on nitrate loading without winter cover crops and to investigate how nitrate loading could change under different winter cover crop planting scenarios, including different species, planting dates, and implementation areas. The simulation results indicate that winter cover crops have a negligible impact on the water budget but significantly reduce nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading from agricultural lands was approximately 14 kg ha-1, but decreased to 4.6-10.1 kg ha-1 with cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was the most effective species, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of cover crops (~ 30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~ 2 kg ha-1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implementation of cover crop programs, in part by helping to target critical pollution source areas for cover crop implementation.

METHODS FOR DETERMINING EXPOSURE TO AND POTENTIAL ECOLOGICAL EFFECTS OF GENE FLOW FROM GENETICALLY MODIFIED CROPS TO COMPATIBLE RELATIVES

EPA Science Inventory

SCIENCE QUESTIONS:

-Does gene flow occur from genetically modified (GM) crop plants to compatible plants?

-How can it be measured?

-Are there ecological consequences of GM crop gene flow to plant communities?



RESEARCH:

The objectives ...

Crop Registration: The Pathway to Public Access of Plant Genetic Materials to Build Crops for the Future

USDA-ARS?s Scientific Manuscript database

Starting as Crop Science Registrations in the American Journal of the Society of Agronomy in 1926, and continuing 80+ years later in the Journal of Plant Registrations, 11,241 plant cultivars, germplasm, parental lines, genetic stocks and mapping populations have been registered as of December 31, 2...

Enhancing (crop) plant photosynthesis by introducing novel genetic diversity.

PubMed

Dann, Marcel; Leister, Dario

2017-09-26

Although some elements of the photosynthetic light reactions might appear to be ideal, the overall efficiency of light conversion to biomass has not been optimized during evolution. Because crop plants are depleted of genetic diversity for photosynthesis, efforts to enhance its efficiency with respect to light conversion to yield must generate new variation. In principle, three sources of natural variation are available: (i) rare diversity within extant higher plant species, (ii) photosynthetic variants from algae, and (iii) reconstruction of no longer extant types of plant photosynthesis. Here, we argue for a novel approach that outsources crop photosynthesis to a cyanobacterium that is amenable to adaptive evolution. This system offers numerous advantages, including a short generation time, virtually unlimited population sizes and high mutation rates, together with a versatile toolbox for genetic manipulation. On such a synthetic bacterial platform, 10 000 years of (crop) plant evolution can be recapitulated within weeks. Limitations of this system arise from its unicellular nature, which cannot reproduce all aspects of crop photosynthesis. But successful establishment of such a bacterial host for crop photosynthesis promises not only to enhance the performance of eukaryotic photosynthesis but will also reveal novel facets of the molecular basis of photosynthetic flexibility.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Author(s).

Sustainable harvest: managing plasticity for resilient crops

PubMed Central

Bloomfield, Justin A; Rose, Terry J; King, Graham J

2014-01-01

Maintaining crop production to feed a growing world population is a major challenge for this period of rapid global climate change. No consistent conceptual or experimental framework for crop plants integrates information at the levels of genome regulation, metabolism, physiology and response to growing environment. An important role for plasticity in plants is assisting in homeostasis in response to variable environmental conditions. Here, we outline how plant plasticity is facilitated by epigenetic processes that modulate chromatin through dynamic changes in DNA methylation, histone variants, small RNAs and transposable elements. We present examples of plant plasticity in the context of epigenetic regulation of developmental phases and transitions and map these onto the key stages of crop establishment, growth, floral initiation, pollination, seed set and maturation of harvestable product. In particular, we consider how feedback loops of environmental signals and plant nutrition affect plant ontogeny. Recent advances in understanding epigenetic processes enable us to take a fresh look at the crosstalk between regulatory systems that confer plasticity in the context of crop development. We propose that these insights into genotype × environment (G × E) interaction should underpin development of new crop management strategies, both in terms of information-led agronomy and in recognizing the role of epigenetic variation in crop breeding. PMID:24891039

Alternative Splicing and Cross-Talk with Light Signaling.

PubMed

Cheng, You-Liang; Tu, Shih-Long

2018-06-01

Alternative splicing (AS) is the main source of proteome diversity that in large part contributes to the complexity of eukaryotes. Recent global analysis of AS with RNA sequencing has revealed that AS is prevalent in plants, particularly when responding to environmental changes. Light is one of the most important environmental factors for plant growth and development. To optimize light absorption, plants evolve complex photoreceptors and signaling systems to regulate gene expression and biological processes in the cell. Genome-wide analyses have shown that light induces intensive AS in plants. However, the biochemical mechanisms of light regulating AS remain poorly understood. In this review, we aim to discuss recent progress in investigating the functions of AS, discovery of cross-talk between AS and light signaling, and the potential mechanism of light-regulated AS. Understanding how light signaling regulates the efficiency of AS and the biological significance of light-regulated AS in plant systems will provide new insights into the adaptation of plants to their environment and, ultimately, crop improvement.

Transgenic, transplastomic and other genetically modified plants: a Canadian perspective.

PubMed

Belzile, François J

2002-11-01

Since the mid 1990s, genetically modified (GM) crops have been grown commercially in Canada on a scale that has increased steadily over the years. An intense debate ensued, as elsewhere, and many fears were expressed regarding not only the technology itself but some of the main GM crops being grown. It would seem appropriate at this time to examine how these novel crops compare to crops bred by more traditional means and what impacts these GM crops have had based on experience and not merely on conjecture. To begin, we will put things in a historical perspective and recall how domestication and conventional plant breeding have shaped the crops of today. Then, we will describe briefly the distinctive features of GM plants (obtained so far mainly by nuclear transgenesis) and how these novel crops are regulated in Canada. We will then give two examples of widely grown GM crops in Canada (insect-resistant corn and herbicide-tolerant canola) and examine the main questions that were raised as well as the actual impacts these crops have had on the farm. These examples will help us outline some of the limitations of the current generation of GM plants and, finally, we will try to get a glimpse of the future by examining some recent technical developments in the field of recombinant DNA technologies applied to plant breeding.

Irrigation and Maize Cultivation Erode Plant Diversity Within Crops in Mediterranean Dry Cereal Agro-Ecosystems.

PubMed

Fagúndez, Jaime; Olea, Pedro P; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David

2016-07-01

The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.

Regulation of Population Densities of Heterodera cajani and Other Plant-Parasitic Nematodes by Crop Rotations on Vertisols, in Semi-Arid Tropical Production Systems in India

PubMed Central

Sharma, S. B.; Rego, T. J.; Mohiuddin, M.; Rao, V. N.

1996-01-01

The significance of double crop (intercrop and sequential crop), single crop (rainy season crop fallow from June to September), and rotations on densities of Heterodera cajani, Helicotylenchus retusus, and Rotylenchulus reniformis was studied on Vertisol (Typic Pellusterts) between 1987 and 1993. Cowpea (Vigna sinensis), mungbean (Phaseolus aureus), and pigeonpea (Cajanus cajan) greatly increased the population densities of H. cajani and suppressed the population densities of other plant-parasitic nematodes. Mean population densities of H. cajani were about 8 times lower in single crop systems than in double crop systems, with pigeonpea as a component intercrop. Plots planted to sorghum, safflower, and chickpea in the preceding year contained fewer H. cajani eggs and juveniles than did plots previously planted to pigeonpea, cowpea, or mungbean. Continuous cropping of sorghum in the rainy season and safflower in the post-rainy season markedly reduced the population density of H. cajani. Sorghum, safflower, and chickpea favored increased population densities of H. retusus. Adding cowpea to the system resulted in a significant increase in the densities of R. reniformis. Mean densities of total plant-parasitic nematodes were three times greater in double crop systems, with pigeonpea as a component intercrop than in single crop systems with rainy season fallow component. Cropping systems had a regulatory effect on the nematode populations and could be an effective nematode management tactic. Intercropping of sorghum with H. cajani tolerant pigeonpea could be effective in increasing the productivity of traditional production systems in H. cajani infested regions. PMID:19277141

Simulating the effects of climate and agricultural management practices on global crop yield

NASA Astrophysics Data System (ADS)

Deryng, D.; Sacks, W. J.; Barford, C. C.; Ramankutty, N.

2011-06-01

Climate change is expected to significantly impact global food production, and it is important to understand the potential geographic distribution of yield losses and the means to alleviate them. This study presents a new global crop model, PEGASUS 1.0 (Predicting Ecosystem Goods And Services Using Scenarios) that integrates, in addition to climate, the effect of planting dates and cultivar choices, irrigation, and fertilizer application on crop yield for maize, soybean, and spring wheat. PEGASUS combines carbon dynamics for crops with a surface energy and soil water balance model. It also benefits from the recent development of a suite of global data sets and analyses that serve as model inputs or as calibration data. These include data on crop planting and harvesting dates, crop-specific irrigated areas, a global analysis of yield gaps, and harvested area and yield of major crops. Model results for present-day climate and farm management compare reasonably well with global data. Simulated planting and harvesting dates are within the range of crop calendar observations in more than 75% of the total crop-harvested areas. Correlation of simulated and observed crop yields indicates a weighted coefficient of determination, with the weighting based on crop-harvested area, of 0.81 for maize, 0.66 for soybean, and 0.45 for spring wheat. We found that changes in temperature and precipitation as predicted by global climate models for the 2050s lead to a global yield reduction if planting and harvesting dates remain unchanged. However, adapting planting dates and cultivar choices increases yield in temperate regions and avoids 7-18% of global losses.

Cytoplasmic male sterility (CMS) in hybrid breeding in field crops.

PubMed

Bohra, Abhishek; Jha, Uday C; Adhimoolam, Premkumar; Bisht, Deepak; Singh, Narendra P

2016-05-01

A comprehensive understanding of CMS/Rf system enabled by modern omics tools and technologies considerably improves our ability to harness hybrid technology for enhancing the productivity of field crops. Harnessing hybrid vigor or heterosis is a promising approach to tackle the current challenge of sustaining enhanced yield gains of field crops. In the context, cytoplasmic male sterility (CMS) owing to its heritable nature to manifest non-functional male gametophyte remains a cost-effective system to promote efficient hybrid seed production. The phenomenon of CMS stems from a complex interplay between maternally-inherited (mitochondrion) and bi-parental (nucleus) genomic elements. In recent years, attempts aimed to comprehend the sterility-inducing factors (orfs) and corresponding fertility determinants (Rf) in plants have greatly increased our access to candidate genomic segments and the cloned genes. To this end, novel insights obtained by applying state-of-the-art omics platforms have substantially enriched our understanding of cytoplasmic-nuclear communication. Concomitantly, molecular tools including DNA markers have been implicated in crop hybrid breeding in order to greatly expedite the progress. Here, we review the status of diverse sterility-inducing cytoplasms and associated Rf factors reported across different field crops along with exploring opportunities for integrating modern omics tools with CMS-based hybrid breeding.

Performance test of nutrient control equipment for hydroponic plants

NASA Astrophysics Data System (ADS)

Rahman, Nurhaidar; Kuala, S. I.; Tribowo, R. I.; Anggara, C. E. W.; Susanti, N. D.

2017-11-01

Automatic control equipment has been made for the nutrient content in irrigation water for hydroponic plants. Automatic control equipment with CCT53200E conductivity controller to nutrient content in irrigation water for hydroponic plants, can be used to control the amount of TDS of nutrient solution in the range of TDS numbers that can be set according to the range of TDS requirements for the growth of hydroponically cultivated crops. This equipment can minimize the work time of hydroponic crop cultivators. The equipment measurement range is set between 1260 ppm up to 1610 ppm for spinach plants. Caisim plants were included in this experiment along with spinach plants with a spinach plants TDS range. The average of TDS device is 1450 ppm, while manual (conventional) is 1610 ppm. Nutrient solution in TDS controller has pH 5,5 and temperature 29,2 °C, while manual is pH 5,6 and temperature 31,3 °C. Manually treatment to hydroponic plant crop, yields in an average of 39.6 grams/plant, greater than the yield of spinach plants with TDS control equipment, which is in an average of 24.6 grams / plant. The yield of caisim plants by manual treatment is in an average of 32.3 grams/crop, less than caisim crop yields with TDS control equipment, which is in an average of 49.4 grams/plant.

Aggressiveness Changes in Populations of Didymella pinodes over Winter and Spring Pea Cropping Seasons.

PubMed

Laloi, G; Montarry, J; Guibert, M; Andrivon, D; Michot, D; Le May, C

2016-07-15

Ascochyta blight, caused by the necrotrophic ascomycete Didymella pinodes, is responsible for severe losses in winter and spring pea crops. Despite different climatic conditions, epidemics on winter and spring crops are due to a single population of D. pinodes, suggesting gene flow either between the two crops or from reservoir sources during the cropping season. This should lead to similar pathogenicity characteristics in isolates sampled from the two crops. However, these hypotheses have never been formally tested. We therefore sampled a total of 520 D. pinodes strains throughout a growing season from winter and spring pea plots (WP and SP, respectively) and from winter and spring trap plants (TWP and TSP). Amplified fragment length polymorphism (AFLP) markers revealed high genetic diversity within subpopulations, whereas pathogenicity tests showed that mean aggressiveness increases over the course of an epidemic. These results support the idea that alloinoculum contributes to the carryover of epidemics between winter and spring crops and that the most aggressive isolates are selected as an epidemic progresses. Ascochyta blight, caused by Didymella pinodes, is responsible for severe losses in pea crops. While previous studies have shown that ascochyta blight epidemics on winter and spring crops are due to a single population of D. pinodes, suggesting that isolates from the two crops present similar pathogenicity characteristics, that hypothesis have never been tested. Genetic analysis of subpopulations sampled throughout a growing season from winter and spring pea plots revealed high genetic diversity within subpopulations, whereas pathogenicity tests showed that mean aggressiveness increases over the course of an epidemic. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Nutritionally enhanced food crops; progress and perspectives.

PubMed

Hefferon, Kathleen L

2015-02-11

Great progress has been made over the past decade with respect to the application of biotechnology to generate nutritionally improved food crops. Biofortified staple crops such as rice, maize and wheat harboring essential micronutrients to benefit the world's poor are under development as well as new varieties of crops which have the ability to combat chronic disease. This review discusses the improvement of the nutritional status of crops to make a positive impact on global human health. Several examples of nutritionally enhanced crops which have been developed using biotechnological approaches will be discussed. These range from biofortified crops to crops with novel abilities to fight disease. The review concludes with a discussion of hurdles faced with respect to public perception, as well as directions of future research and development for nutritionally enhanced food crops.

Toward mapping crop progress at field scales through fusion of Landsat and MODIS imagery

USDA-ARS?s Scientific Manuscript database

Crop progress and condition are required for crop management and yield estimation. In the United States, they are reported weekly at state or district level by the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service (NASS) using the field observations provided by local far...

Hop (Humulus lupulus L.) response mechanisms in drought stress: Proteomic analysis with physiology.

PubMed

Kolenc, Zala; Vodnik, Dominik; Mandelc, Stanislav; Javornik, Branka; Kastelec, Damijana; Čerenak, Andreja

2016-08-01

Drought is one of the major environmental devastating stressors that impair the growth and productivity of crop plants. Despite the relevance of drought stress, changes in physiology and resistance mechanisms are not completely understood for certain crops, including hop (Humulus lupulus L.). In this research the drought response of hop was studied using a conventional physiological approach (gas exchange techniques, fluorescence, relative water content measurements) and proteomic analysis (2D-DIGE). Plants of two cultivars (Aurora and Savinjski golding) were exposed to progressive drought in a pot experiment and analysed at different stress stages (mild, moderate and severe). Measurements of relative water content revealed a hydrostable water balance of hop. Photosynthesis was decreased due to stomatal and non-stomatal limitation to the same extent in both cultivars. Of 28 identified differentially abundant proteins, the majority were down regulated and included in photosynthetic (41%) and sugar metabolism (33%). Fifteen % of identified proteins were classified into the nitrogen metabolism, 4% were related to a ROS related pathway and 7% to other functions. Copyright © 2016. Published by Elsevier Masson SAS.

Adapting to warmer climate through prolonged maize grain filling period in the US Midwest

NASA Astrophysics Data System (ADS)

Zhu, P.; Zhuang, Q.; Jin, Z.

2017-12-01

Climate warming is expected to negatively impact the US food productivity. How to adapt to the future warmer environment and meet the rising food requirement becomes unprecedented urgent. Continuous satellite observational data provides an opportunity to examine the historic responses of crop plants to climate variation. Here 16 years crop growing phases information across US Midwest is generated based on satellite observations. We found a prolonged grain-filling period during 2000-2015, which could partly explain the increasing trend in Midwest maize yield. This longer grain-filling period might be resulted from the adoption of longer maturity group varieties or more resistant varieties to temperature variation. Other management practice changes like advance in planting date could be also an effective way of adapting future warmer climate through lowering the possibility of exposure to heat and drought stresses. If the progress in breeding technology enables the maize grain-filling period to prolong with the current rate, the maize grain filling length could be longer and maize yield in Midwest could adapt to future climate despite of the warming.

Metabolic engineering of sugars and simple sugar derivatives in plants.

PubMed

Patrick, John W; Botha, Frikkie C; Birch, Robert G

2013-02-01

Carbon captured through photosynthesis is transported, and sometimes stored in plants, as sugar. All organic compounds in plants trace to carbon from sugars, so sugar metabolism is highly regulated and integrated with development. Sugars stored by plants are important to humans as foods and as renewable feedstocks for industrial conversion to biofuels and biomaterials. For some purposes, sugars have advantages over polymers including starches, cellulose or storage lipids. This review considers progress and prospects in plant metabolic engineering for increased yield of endogenous sugars and for direct production of higher-value sugars and simple sugar derivatives. Opportunities are examined for enhancing export of sugars from leaves. Focus then turns to manipulation of sugar metabolism in sugar-storing sink organs such as fruits, sugarcane culms and sugarbeet tubers. Results from manipulation of suspected 'limiting' enzymes indicate a need for clearer understanding of flux control mechanisms, to achieve enhanced levels of endogenous sugars in crops that are highly selected for this trait. Outcomes from in planta conversion to novel sugars and derivatives range from severe interference with plant development to field demonstration of crops accumulating higher-value sugars at high yields. The differences depend on underlying biological factors including the effects of the novel products on endogenous metabolism, and on biotechnological fine-tuning including developmental expression and compartmentation patterns. Ultimately, osmotic activity may limit the accumulation of sugars to yields below those achievable using polymers; but results indicate the potential for increases above current commercial sugar yields, through metabolic engineering underpinned by improved understanding of plant sugar metabolism. © 2012 The Authors Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Robust crop and weed segmentation under uncontrolled outdoor illumination.

PubMed

Jeon, Hong Y; Tian, Lei F; Zhu, Heping

2011-01-01

An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect weeds and crop plants under uncontrolled outdoor illuminations. A machine vision implementing field robot captured field images under outdoor illuminations and the image processing algorithm automatically processed them without manual adjustment. The errors of the algorithm, when processing 666 field images, ranged from 2.1 to 2.9%. The ANN correctly detected 72.6% of crop plants from the identified plants, and considered the rest as weeds. However, the ANN identification rates for crop plants were improved up to 95.1% by addressing the error sources in the algorithm. The developed weed detection and image processing algorithm provides a novel method to identify plants against soil background under the uncontrolled outdoor illuminations, and to differentiate weeds from crop plants. Thus, the proposed new machine vision and processing algorithm may be useful for outdoor applications including plant specific direct applications (PSDA).

Endophytic fungi occurring in fennel, lettuce, chicory, and celery--commercial crops in southern Italy.

PubMed

D'Amico, Margherita; Frisullo, Salvatore; Cirulli, Matteo

2008-01-01

The occurrence of endophytic fungi in fennel, lettuce, chicory, and celery crops was investigated in southern Italy. A total of 186 symptomless plants was randomly collected and sampled at the stage of commercial ripeness. Fungal species of Acremonium, Alternaria, Fusarium, and Plectosporium were detected in all four crops; Plectosporium tabacinum was the most common in all crop species and surveyed sites. The effect of eight endophytic isolates (five belonging to Plectosporium tabacinum and three to three species of Acremonium) inoculated on lettuce plants grown in gnotobiosis was assessed by recording plant height, root length and dry weight, collar diameter, root necrosis, and leaf yellowing. P. tabacinum and three species of Acremonium, inoculated on gnotobiotically grown lettuce plants, showed pathogenic activity that varied with the fungal isolate. Lettuce plants inoculated with the isolates Ak of Acremonium kiliense, Ac of Acremonium cucurbitacearum, and P35 of P. tabacinum showed an increased root growth, compared to the non-inoculated control. The high frequency of P. tabacinum isolation recorded in lettuce plants collected in Bari and Metaponto, and in fennel plants from Foggia agricultural districts, suggests a relationship not only between a crop species and P. tabacinum, but also between the occurrence of the endophyte and the crop rotation history of the soil.

Extraction and Analysis of Traditional Chinese Medicine Crops Based on Multitemporal High Resolution Data-Taking Qiaocheng District of Bozhou as AN Example

NASA Astrophysics Data System (ADS)

Yu, H.; He, J.; Zhou, H.; Guan, F.; Li, L.; Ren, B.; Wang, Z.

2018-04-01

Remote sensing technology has become an important method to rapidly acquireing of planting layout and composition of regional crops.It is very important to accurately master the planting area of Chinese medicine crops in the Characteristic planting area because it relations to accurately master the cultivation of Chinese medicine crops, formulate related policies and adjustment of crop planting structure.The author puts forward a method of using remote sencing technology for momitoring Chinese medicine which has good applicability and generalization. This paper took Qiaocheng District of Bozhou as an example to Verify the feasibility of the method, providing a reference for solving the problem of interpretation and extraction of Chinese medicinal materials in the region.

Forages and Pastures Symposium: development of and field experience with drought-tolerant maize.

PubMed

Soderlund, S; Owens, F N; Fagan, C

2014-07-01

Drought-tolerant maize hybrids currently are being marketed by several seed suppliers. Such hybrids were developed by phenotypic and marker-assisted selection or through genetic modification and tested by exposing these hybrids to various degrees of water restriction. As drought intensifies, crop yields and survival progressively decline. Water need differs among plants due to differences in root structure, evaporative loss, capacity to store water or enter temporary dormancy, and plant genetics. Availability of water differs widely not only with rainfall and irrigation but also with numerous soil and agronomic factors (e.g., soil type, slope, seeding rates, tillage practices). Reduced weed competition, enhanced pollen shed and silk production, and deep, robust root growth help to reduce the negative impacts of drought. Selected drought-tolerant maize hybrids have consistently yielded more grain even when drought conditions are not apparent either due to reduced use of soil water reserves before water restriction or due to greater tolerance of intermittent water shortages. In DuPont Pioneer trials, whole plant NDF digestibility of maize increased with water restriction, perhaps due to an increased leaf to stem ratio. Efficiency of water use, measured as dry matter or potential milk yield from silage per unit of available water, responded quadratically to water restriction, first increasing slightly but then decreasing as water restriction increased. For grain production, water restriction has its greatest negative impact during or after silking through reducing the number of kernels and reducing kernel filling. For silage production, water restriction during the vegetative growth stage negatively impacts plant height and biomass yield. Earlier planting and shorter season maize hybrids help to avoid midsummer heat stress during pollination and can reduce the number of irrigation events needed. Although drought tolerance of maize hybrids has been improved due to genetic selection or biotech approaches, selecting locally adapted hybrids or crops, adjusting seeding rates, and modifying tillage and irrigation practices are important factors that can improve efficiency of use of available water by grain and forage crops.

7 CFR 457.116 - Sugarcane crop insurance provisions.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) That is grown for processing for sugar or for seed; and (3) That is not interplanted with another crop... market the sugarcane. Plant cane. The insured crop which grows from seed planted for the crop year... Seed (a) In addition to your duties under section 14 of the Basic Provisions (§ 457.8), in the event of...

7 CFR 457.116 - Sugarcane crop insurance provisions.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) That is grown for processing for sugar or for seed; and (3) That is not interplanted with another crop... market the sugarcane. Plant cane. The insured crop which grows from seed planted for the crop year... Seed (a) In addition to your duties under section 14 of the Basic Provisions (§ 457.8), in the event of...

7 CFR 457.116 - Sugarcane crop insurance provisions.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) That is grown for processing for sugar or for seed; and (3) That is not interplanted with another crop... market the sugarcane. Plant cane. The insured crop which grows from seed planted for the crop year... Seed (a) In addition to your duties under section 14 of the Basic Provisions (§ 457.8), in the event of...

Effectiveness of insecticide-treated and non-treated trap plants for the management of Frankliniella occidentalis (Thysanoptera: Thripidae) in greenhouse ornamentals.

PubMed

Buitenhuis, Rosemarije; Shipp, J Les; Jandricic, Sarah; Murphy, Graeme; Short, Mike

2007-09-01

The effectiveness of trap cropping as an integrated control strategy against western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), was explored in potted chrysanthemum, Dendranthema grandiflora (Tzvelev), greenhouse crops. The efficacy of flowering chrysanthemum trap plants, either treated with the insecticide spinosad or untreated, to regulate F. occidentalis populations was tested at different spatial scales (small cage, large cage and commercial greenhouse) and for different time periods (1 or 4 weeks). It was demonstrated that flowering chrysanthemums as trap plants lower the number of adult F. occidentalis in a vegetative chrysanthemum crop and, as a result, reduce crop damage. In the 4 week large-cage trial and the commercial trial, significant differences between the control and the trap plant treatments started to appear in the third week of the experiment. Larvae were only significantly reduced by the presence of trap plants in the 1 week small-cage trials. There were no significant differences between treatments with spinosad-treated and untreated trap plants in the number of F. occidentalis on the crop. This suggests that there was minimal movement of adult F. occidentalis back and forth between the trap plants and the crop to feed and oviposit. It is concluded that the trap plant strategy is a useful tool for integrated pest management against F. occidentalis in greenhouses. 2007 Crown in the right of Canada

Non-Crop Host Sampling Yields Insights into Small-Scale Population Dynamics of Drosophila suzukii (Matsumura)

PubMed Central

Loeb, Gregory M.

2018-01-01

Invasive, polyphagous crop pests subsist on a number of crop and non-crop resources. While knowing the full range of host species is important, a seasonal investigation into the use of non-crop plants adjacent to cropping systems provide key insights into some of the factors determining local population dynamics. This study investigated the infestation of non-crop plants by the invasive Drosophila suzukii (Matsumura), a pest of numerous economically important stone and small fruit crops, by sampling fruit-producing non-crop hosts adjacent to commercial plantings weekly from June through November in central New York over a two-year period. We found D. suzukii infestation rates (number of flies emerged/kg fruit) peaked mid-August through early September, with Rubus allegheniensis Porter and Lonicera morrowii Asa Gray showing the highest average infestation in both years. Interannual infestation patterns were similar despite a lower number of adults caught in monitoring traps the second year, suggesting D. suzukii host use may be density independent. PMID:29301358

Genome-wide analysis of drought induced gene expression changes in flax (Linum usitatissimum).

PubMed

Dash, Prasanta K; Cao, Yongguo; Jailani, Abdul K; Gupta, Payal; Venglat, Prakash; Xiang, Daoquan; Rai, Rhitu; Sharma, Rinku; Thirunavukkarasu, Nepolean; Abdin, Malik Z; Yadava, Devendra K; Singh, Nagendra K; Singh, Jas; Selvaraj, Gopalan; Deyholos, Mike; Kumar, Polumetla Ananda; Datla, Raju

2014-01-01

A robust phenotypic plasticity to ward off adverse environmental conditions determines performance and productivity in crop plants. Flax (linseed), is an important cash crop produced for natural textile fiber (linen) or oilseed with many health promoting products. This crop is prone to drought stress and yield losses in many parts of the world. Despite recent advances in drought research in a number of important crops, related progress in flax is very limited. Since, response of this plant to drought stress has not been addressed at the molecular level; we conducted microarray analysis to capture transcriptome associated with induced drought in flax. This study identified 183 differentially expressed genes (DEGs) associated with diverse cellular, biophysical and metabolic programs in flax. The analysis also revealed especially the altered regulation of cellular and metabolic pathways governing photosynthesis. Additionally, comparative transcriptome analysis identified a plethora of genes that displayed differential regulation both spatially and temporally. These results revealed co-regulated expression of 26 genes in both shoot and root tissues with implications for drought stress response. Furthermore, the data also showed that more genes are upregulated in roots compared to shoots, suggesting that roots may play important and additional roles in response to drought in flax. With prolonged drought treatment, the number of DEGs increased in both tissue types. Differential expression of selected genes was confirmed by qRT-PCR, thus supporting the suggested functional association of these intrinsic genes in maintaining growth and homeostasis in response to imminent drought stress in flax. Together the present study has developed foundational and new transcriptome data sets for drought stress in flax.

Phytoplasmas–The “Crouching Tiger” Threat of Australian Plant Pathology

PubMed Central

Liu, Jian; Gopurenko, David; Fletcher, Murray J.; Johnson, Anne C.; Gurr, Geoff M.

2017-01-01

Phytoplasmas are insect-vectored bacteria that cause disease in a wide range of plant species. The increasing availability of molecular DNA analyses, expertise and additional methods in recent years has led to a proliferation of discoveries of phytoplasma-plant host associations and in the numbers of taxonomic groupings for phytoplasmas. The widespread use of common names based on the diseases with which they are associated, as well as separate phenetic and taxonomic systems for classifying phytoplasmas based on variation at the 16S rRNA-encoding gene, complicates interpretation of the literature. We explore this issue and related trends through a focus on Australian pathosystems, providing the first comprehensive compilation of information for this continent, covering the phytoplasmas, host plants, vectors and diseases. Of the 33 16Sr groups reported internationally, only groups I, II, III, X, XI and XII have been recorded in Australia and this highlights the need for ongoing biosecurity measures to prevent the introduction of additional pathogen groups. Many of the phytoplasmas reported in Australia have not been sufficiently well studied to assign them to 16Sr groups so it is likely that unrecognized groups and sub-groups are present. Wide host plant ranges are apparent among well studied phytoplasmas, with multiple crop and non-crop species infected by some. Disease management is further complicated by the fact that putative vectors have been identified for few phytoplasmas, especially in Australia. Despite rapid progress in recent years using molecular approaches, phytoplasmas remain the least well studied group of plant pathogens, making them a “crouching tiger” disease threat. PMID:28491068

Advances in crop proteomics: PTMs of proteins under abiotic stress.

PubMed

Wu, Xiaolin; Gong, Fangping; Cao, Di; Hu, Xiuli; Wang, Wei

2016-03-01

Under natural conditions, crop plants are frequently subjected to various abiotic environmental stresses such as drought and heat wave, which may become more prevalent in the coming decades. Plant acclimation and tolerance to an abiotic stress are always associated with significant changes in PTMs of specific proteins. PTMs are important for regulating protein function, subcellular localization and protein activity and stability. Studies of plant responses to abiotic stress at the PTMs level are essential to the process of plant phenotyping for crop improvement. The ability to identify and quantify PTMs on a large-scale will contribute to a detailed protein functional characterization that will improve our understanding of the processes of crop plant stress acclimation and stress tolerance acquisition. Hundreds of PTMs have been reported, but it is impossible to review all of the possible protein modifications. In this review, we briefly summarize several main types of PTMs regarding their characteristics and detection methods, review the advances in PTMs research of crop proteomics, and highlight the importance of specific PTMs in crop response to abiotic stress. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microgravity as a research tool to improve US agriculture

NASA Astrophysics Data System (ADS)

Bula, R. J.; Stankovic, Bratislav

2000-01-01

Crop production and utilization are undergoing significant modifications and improvements that emanate from adaptation of recently developed plant biotechnologies. Several innovative technologies will impact US agriculture in the next century. One of these is the transfer of desirable genes from organisms to economically important crop species in a way that cannot be accomplished with traditional plant breeding techniques. Such plant genetic engineering offers opportunities to improve crop species for a number of characteristics as well as use as source materials for specific medical and industrial applications. Although plant genetic engineering is having an impact on development of new crop cultivars, several major constraints limit the application of this technology to selected crop species and genotypes. Consequently, gene transfer systems that overcome these constraints would greatly enhance development of new crop materials. If results of a recent gene transfer experiment conducted in microgravity during a Space Shuttle mission are confirmed, and with the availability of the International Space Station as a permanent space facility, commercial plant transformation activity in microgravity could become a new research tool to improve US agriculture. .

Development of an early warning system of crop moisture conditions using passive microwave

NASA Technical Reports Server (NTRS)

Mcfarland, M. J.; Harder, P. H., II (Principal Investigator)

1982-01-01

Emissivities were calculated from the Nimbus 5 electrically scanning microwave radiometer (ESMR) over 25 km grid cells for the southern Great Plains includin the western two-thirds of Kansas and Oklahoma and northwest Texas. These emissivities, normalized for seasonal temperature changes, were in excellent agreement with theory and measurements made from aircraft and truck sensors at the 1.55 cm wavelength of ESMR. These emissivities were related to crop moisture conditions of the winter wheat in the major wheat producing counties of the three states. High correlations were noted between emissitivity and an antecedent precipitation index (API) used to infer soil moisture for periods when the soils were essentially bare. The emissivities from ESMR were related through API and actual crop condition reports to progress of fall planting, adequacy of crop moisture for stand establishment, and periods of excessive moisture that necessitated replanting. Periods of prolonged frozen soil in the winter were observable at several grid points. The average emissivities of the canopy/soil surface during the maximum canopy development times in the spring showed a good agreement with moisture stress inferred from rainfall and yield data.

A dual indicator set to help farms achieve more sustainable crop protection.

PubMed

Wustenberghs, Hilde; Delcour, Ilse; D'Haene, Karoline; Lauwers, Ludwig; Marchand, Fleur; Steurbaut, Walter; Spanoghe, Pieter

2012-08-01

Farmers are being called to use plant protection products (PPPs) more consciously and adopt more sustainable crop protection strategies. Indicators will help farmers to monitor their progress towards sustainability and will support their learning process. Talking the indicators through in farmers' discussion groups and the resulting peer encouragement will foster knowledge acquirement and can lead to changes in attitudes, norms, perception and behaviour. Using a participatory approach, a conceptual framework for on-farm sustainable crop protection practices was created. The same participatory approach was used to design a dual indicator set, which pairs a pesticide impact assessment system (PIAS) with a farm inquiry. The PIAS measures the risk for human health and the environment exerted by chemical crop protection. The inquiry reveals the farmers' response to this risk, both in terms of the actions they take and their knowledge, awareness and attitude. The dual indicator set allows for implementation in four tiers, each representing increased potential for monitoring and social learning. The indicator set can be adjusted on the basis of new findings, and the participatory approach can be extrapolated to other situations. Copyright © 2012 Society of Chemical Industry.

Traditional and modern plant breeding methods with examples in rice (Oryza sativa L.).

PubMed

Breseghello, Flavio; Coelho, Alexandre Siqueira Guedes

2013-09-04

Plant breeding can be broadly defined as alterations caused in plants as a result of their use by humans, ranging from unintentional changes resulting from the advent of agriculture to the application of molecular tools for precision breeding. The vast diversity of breeding methods can be simplified into three categories: (i) plant breeding based on observed variation by selection of plants based on natural variants appearing in nature or within traditional varieties; (ii) plant breeding based on controlled mating by selection of plants presenting recombination of desirable genes from different parents; and (iii) plant breeding based on monitored recombination by selection of specific genes or marker profiles, using molecular tools for tracking within-genome variation. The continuous application of traditional breeding methods in a given species could lead to the narrowing of the gene pool from which cultivars are drawn, rendering crops vulnerable to biotic and abiotic stresses and hampering future progress. Several methods have been devised for introducing exotic variation into elite germplasm without undesirable effects. Cases in rice are given to illustrate the potential and limitations of different breeding approaches.

Soil coverage evolution and wind erosion risk on summer crops under contrasting tillage systems

NASA Astrophysics Data System (ADS)

Mendez, Mariano J.; Buschiazzo, Daniel E.

2015-03-01

The effectiveness of wind erosion control by soil surface conditions and crop and weed canopy has been well studied in wind tunnel experiments. The aim of this study is to assess the combined effects of these variables under field conditions. Soil surface conditions, crop and weed coverage, plant residue, and non-erodible aggregates (NEA) were measured in the field between the fallow start and the growth period of sunflower (Helianthus annuus) and corn (Zea mays). Both crops were planted on a sandy-loam Entic Haplustoll with conventional-(CT), vertical-(VT) and no-till (NT) tillage systems. Wind erosion was estimated by means of the spreadsheet version the Revised Wind Erosion Equation and the soil coverage was measured each 15 days. Results indicated that wind erosion was mostly negligible in NT, exceeding the tolerable levels (estimated between 300 and 1400 kg ha-1 year-1 by Verheijen et al. (2009)) only in an year with high climatic erosivity. Wind erosion exceeded the tolerable levels in most cases in CT and VT, reaching values of 17,400 kg ha-1. Wind erosion was 2-10 times higher after planting of both crops than during fallows. During the fallows, the soil was mostly well covered with plant residues and NEA in CT and VT and with residues and weeds in NT. High wind erosion amounts occurring 30 days after planting in all tillage systems were produced by the destruction of coarse aggregates and the burying of plant residues during planting operations and rains. Differences in soil protection after planting were given by residues of previous crops and growing weeds. The growth of weeds 2-4 weeks after crop planting contributed to reduce wind erosion without impacting in crops yields. An accurate weeds management in semiarid lands can contribute significantly to control wind erosion. More field studies are needed in order to develop management strategies to reduce wind erosion.

Nutritionally Enhanced Food Crops; Progress and Perspectives

PubMed Central

Hefferon, Kathleen L.

2015-01-01

Great progress has been made over the past decade with respect to the application of biotechnology to generate nutritionally improved food crops. Biofortified staple crops such as rice, maize and wheat harboring essential micronutrients to benefit the world’s poor are under development as well as new varieties of crops which have the ability to combat chronic disease. This review discusses the improvement of the nutritional status of crops to make a positive impact on global human health. Several examples of nutritionally enhanced crops which have been developed using biotechnological approaches will be discussed. These range from biofortified crops to crops with novel abilities to fight disease. The review concludes with a discussion of hurdles faced with respect to public perception, as well as directions of future research and development for nutritionally enhanced food crops. PMID:25679450

Plant breeding and genetics

USDA-ARS?s Scientific Manuscript database

The ultimate goal of plant breeding is to develop improved crops. Improvements can be made in crop productivity, crop processing and marketing, and/or consumer quality. The process of developing an improved cultivar begins with intercrossing lines with high performance for the traits of interest, th...

Integration of Plant Defense Traits with Biological Control of Arthropod Pests: Challenges and Opportunities

PubMed Central

Peterson, Julie A.; Ode, Paul J.; Oliveira-Hofman, Camila; Harwood, James D.

2016-01-01

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically, plant toxin-, plant nutrient-, and/or physically mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP) traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management. PMID:27965695

Integration of Plant Defense Traits with Biological Control of Arthropod Pests: Challenges and Opportunities.

PubMed

Peterson, Julie A; Ode, Paul J; Oliveira-Hofman, Camila; Harwood, James D

2016-01-01

Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically, plant toxin-, plant nutrient-, and/or physically mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP) traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management.

SELECTING PLANT SPECIES FOR PESTICIDE REGISTRATION TESTS

EPA Science Inventory

Current test protocols used by the US EPA for the registration of pesticides examines plant responses of 10 crop species but may not examine regionally important native plants or crops. In order to test the efficiency of current test protocols we selected six native plant species...

Lettuce germplasm collection in the National Plant Germplasm System

USDA-ARS?s Scientific Manuscript database

The National Plant Germplasm System (NPGS) holds more than half million accessions of crop plants and their related species that are coordinately assigned to four major Regional Plant Introduction Stations and an additional 21 crop-specific repositories. These Stations and repositories acquire, main...

Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

PubMed

Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P

2015-01-01

Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China

PubMed Central

Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P.

2015-01-01

Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China. PMID:26439928

Climate Impacts of Cover Crops

NASA Astrophysics Data System (ADS)

Lombardozzi, D.; Wieder, W. R.; Bonan, G. B.; Morris, C. K.; Grandy, S.

2016-12-01

Cover crops are planted in agricultural rotation with the intention of protecting soil rather than harvest. Cover crops have numerous environmental benefits that include preventing soil erosion, increasing soil fertility, and providing weed and pest control- among others. In addition to localized environmental benefits, cover crops can have important regional or global biogeochemical impacts by increasing soil organic carbon, changing emissions of greenhouse trace gases like nitrous oxide and methane, and reducing hydrologic nitrogen losses. Cover crops may additionally affect climate by changing biogeophysical processes, like albedo and latent heat flux, though these potential changes have not yet been evaluated. Here we use the coupled Community Atmosphere Model (CAM5) - Community Land Model (CLM4.5) to test how planting cover crops in the United States may change biogeophysical fluxes and climate. We present seasonal changes in albedo, heat fluxes, evaporative partitioning, radiation, and the resulting changes in temperature. Preliminary analyses show that during seasons when cover crops are planted, latent heat flux increases and albedo decreases, changing the evaporative fraction and surface temperatures. Understanding both the biogeophysical changes caused by planting cover crops in this study and the biogeochemical changes found in other studies will give a clearer picture of the overall impacts of cover crops on climate and atmospheric chemistry, informing how this land use strategy will impact climate in the future.

Digital imaging of root traits (DIRT): a high-throughput computing and collaboration platform for field-based root phenomics.

PubMed

Das, Abhiram; Schneider, Hannah; Burridge, James; Ascanio, Ana Karine Martinez; Wojciechowski, Tobias; Topp, Christopher N; Lynch, Jonathan P; Weitz, Joshua S; Bucksch, Alexander

2015-01-01

Plant root systems are key drivers of plant function and yield. They are also under-explored targets to meet global food and energy demands. Many new technologies have been developed to characterize crop root system architecture (CRSA). These technologies have the potential to accelerate the progress in understanding the genetic control and environmental response of CRSA. Putting this potential into practice requires new methods and algorithms to analyze CRSA in digital images. Most prior approaches have solely focused on the estimation of root traits from images, yet no integrated platform exists that allows easy and intuitive access to trait extraction and analysis methods from images combined with storage solutions linked to metadata. Automated high-throughput phenotyping methods are increasingly used in laboratory-based efforts to link plant genotype with phenotype, whereas similar field-based studies remain predominantly manual low-throughput. Here, we present an open-source phenomics platform "DIRT", as a means to integrate scalable supercomputing architectures into field experiments and analysis pipelines. DIRT is an online platform that enables researchers to store images of plant roots, measure dicot and monocot root traits under field conditions, and share data and results within collaborative teams and the broader community. The DIRT platform seamlessly connects end-users with large-scale compute "commons" enabling the estimation and analysis of root phenotypes from field experiments of unprecedented size. DIRT is an automated high-throughput computing and collaboration platform for field based crop root phenomics. The platform is accessible at http://www.dirt.iplantcollaborative.org/ and hosted on the iPlant cyber-infrastructure using high-throughput grid computing resources of the Texas Advanced Computing Center (TACC). DIRT is a high volume central depository and high-throughput RSA trait computation platform for plant scientists working on crop roots. It enables scientists to store, manage and share crop root images with metadata and compute RSA traits from thousands of images in parallel. It makes high-throughput RSA trait computation available to the community with just a few button clicks. As such it enables plant scientists to spend more time on science rather than on technology. All stored and computed data is easily accessible to the public and broader scientific community. We hope that easy data accessibility will attract new tool developers and spur creative data usage that may even be applied to other fields of science.

Looking forward to genetically edited fruit crops.

PubMed

Nagamangala Kanchiswamy, Chidananda; Sargent, Daniel James; Velasco, Riccardo; Maffei, Massimo E; Malnoy, Mickael

2015-02-01

The availability of genome sequences for many fruit crops has redefined the boundaries of genetic engineering and genetically modified (GM) crop plants. However commercialization of GM crops is hindered by numerous regulatory and social hurdles. Here, we focus on recently developed genome-editing tools for fruit crop improvement and their importance from the consumer perspective. Challenges and opportunities for the deployment of new genome-editing tools for fruit plants are also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tick Tock: Circadian Regulation of Plant Innate Immunity.

PubMed

Lu, Hua; McClung, C Robertson; Zhang, Chong

2017-08-04

Many living organisms on Earth have evolved the ability to integrate environmental and internal signals to determine time and thereafter adjust appropriately their metabolism, physiology, and behavior. The circadian clock is the endogenous timekeeper critical for multiple biological processes in many organisms. A growing body of evidence supports the importance of the circadian clock for plant health. Plants activate timed defense with various strategies to anticipate daily attacks of pathogens and pests and to modulate responses to specific invaders in a time-of-day-dependent manner (gating). Pathogen infection is also known to reciprocally modulate clock activity. Such a cross talk likely reflects the adaptive nature of plants to coordinate limited resources for growth, development, and defense. This review summarizes recent progress in circadian regulation of plant innate immunity with a focus on the molecular events linking the circadian clock and defense. More and better knowledge of clock-defense cross talk could help to improve disease resistance and productivity in economically important crops.

Advancing environmental risk assessment for transgenic biofeedstock crops

PubMed Central

Wolt, Jeffrey D

2009-01-01

Transgenic modification of plants is a key enabling technology for developing sustainable biofeedstocks for biofuels production. Regulatory decisions and the wider acceptance and development of transgenic biofeedstock crops are considered from the context of science-based risk assessment. The risk assessment paradigm for transgenic biofeedstock crops is fundamentally no different from that of current generation transgenic crops, except that the focus of the assessment must consider the unique attributes of a given biofeedstock crop and its environmental release. For currently envisioned biofeedstock crops, particular emphasis in risk assessment will be given to characterization of altered metabolic profiles and their implications relative to non-target environmental effects and food safety; weediness and invasiveness when plants are modified for abiotic stress tolerance or are domesticated; and aggregate risk when plants are platforms for multi-product production. Robust risk assessments for transgenic biofeedstock crops are case-specific, initiated through problem formulation, and use tiered approaches for risk characterization. PMID:19883509

Researching Seeds: Films, Sanitation Methods, Microbiological Growth, Viability, and Selection for New Crops

NASA Technical Reports Server (NTRS)

Padgett, Niki; Smith, Trent

2018-01-01

A major factor in long-term human exploration of the solar system is crop growth in microgravity. Space crops can provide fresh, nutritious food to supplement diets for astronauts. Important factors impacting space plant growth and consumption are water delivery to root zone in microgravity, sanitation methods for microbiological safety, plant responses to light quality/spectrum, and identifying optimal edible plants suitable for growth on the International Space Station (ISS). Astronauts growing their own food on the ISS provides necessary data for crop production for long duration deep space missions. The seed film project can be used in Advanced Plant Habitat and Veggies that are currently being utilized on the ISS.

Management of Yellowmargined Leaf Beetle Microtheca ochroloma (Coleoptera: Chrysomelidae) Using Turnip as a Trap Crop.

PubMed

Balusu, Rammohan; Rhodes, Elena; Liburd, Oscar; Fadamiro, Henry

2015-12-01

The yellowmargined leaf beetle, Microtheca ochroloma Stål, is a major pest of cruciferous vegetable crops in organic production systems. Very few organically acceptable management options are currently available for this pest. Field studies were conducted at a research station in Alabama and at a commercial organic vegetable farm in Florida to investigate the effectiveness of turnip, Brassica rapa rapa, as a trap crop for M. ochroloma. In the research station trial with cabbage planted as the cash crop, perimeter planting of turnip as a trap crop effectively reduced beetle numbers and crop damage below levels recorded in the control. During the first season of our on-farm trial, with napa cabbage and mustard as the cash crops, using turnip as a trap crop effectively reduced both beetle numbers and cash crop damage below levels found in the control plots, but economic damage was still high. In the second season, beetle populations were too low for significant differences in damage levels to occur between the trap crop and control plots. Together, these results suggest that turnip planted as a trap crop can be an effective control tactic for cruciferous crops, like cabbage, that are much less attractive to M. ochroloma than turnip. In crops, like mustard and napa cabbage, that are equally or only slightly less attractive than turnip, planting turnip as a trap crop would have to be used in combination with other tactics to manage M. ochroloma. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Genetically Engineered Plants and Foods: A Scientist's Analysis of the Issues (Part I).

PubMed

Lemaux, Peggy G

2008-01-01

Through the use of the new tools of genetic engineering, genes can be introduced into the same plant or animal species or into plants or animals that are not sexually compatible-the latter is a distinction with classical breeding. This technology has led to the commercial production of genetically engineered (GE) crops on approximately 250 million acres worldwide. These crops generally are herbicide and pest tolerant, but other GE crops in the pipeline focus on other traits. For some farmers and consumers, planting and eating foods from these crops are acceptable; for others they raise issues related to safety of the foods and the environment. In Part I of this review some general and food issues raised regarding GE crops and foods will be addressed. Responses to these issues, where possible, cite peer-reviewed scientific literature. In Part II to appear in 2009, issues related to environmental and socioeconomic aspects of GE crops and foods will be covered.

Estimating biophysical properties of coffee (Coffea canephora) plants with above-canopy field measurements, using CropSpec®

NASA Astrophysics Data System (ADS)

Putra, Bayu T. Widjaja; Soni, Peeyush; Morimoto, Eiji; Pujiyanto, Pujiyanto

2018-04-01

Remote sensing technologies have been applied to many crops, but tree crops like Robusta coffee (Coffea canephora) under shade conditions require additional attention while making above-canopy measurements. The objective of this study was to determine how well chlorophyll and nitrogen status of Robusta coffee plants can be estimated with the laser-based (CropSpec®) active sensor. This study also identified appropriate vegetation indices for estimating Nitrogen content by above-canopy measurement, using near-infra red and red-edge bands. Varying light intensity and different background of the plants were considered in developing the indices. Field experiments were conducted involving different non-destructive tools (CropSpec® and SPAD-502 chlorophyll meter). Subsequently, Kjeldahl laboratory analyses were performed to determine the actual Nitrogen content of the plants with different ages and field conditions used in the non-destructive previous stage. Measurements were undertaken for assessing the biophysical properties of tree plant. The usefulness of near-infrared and red-edge bands from these sensors in measuring critical nitrogen levels of coffee plants by above-canopy measurement are investigated in this study.

The method for detecting biological parameter of rice growth and early planting of paddy crop by using multi temporal remote sensing data

NASA Astrophysics Data System (ADS)

Domiri, D. D.

2017-01-01

Rice crop is the most important food crop for the Asian population, especially in Indonesia. During the growth of rice plants have four main phases, namely the early planting or inundation phase, the vegetative phase, the generative phase, and bare land phase. Monitoring the condition of the rice plant needs to be conducted in order to know whether the rice plants have problems or not in its growth. Application of remote sensing technology, which uses satellite data such as Landsat 8 and others which has a spatial and temporal resolution is high enough for monitoring the condition of crops such as paddy crop in a large area. In this study has been made an algorithm for monitoring rapidly of rice growth condition using Maximum of Vegetation Index (EVI Max). The results showed that the time of early planting can be estimated if known when EVI Max occurred. The value of EVI Max and when it occured can be known by trough spatial analysis of multitemporal EVI Landsat 8 or other medium spatial resolution satellites.

Fusarium graminearum and Its Interactions with Cereal Heads: Studies in the Proteomics Era

PubMed Central

Yang, Fen; Jacobsen, Susanne; Jørgensen, Hans J. L.; Collinge, David B.; Svensson, Birte; Finnie, Christine

2013-01-01

The ascomycete fungal pathogen Fusarium graminearum (teleomorph stage: Gibberella zeae) is the causal agent of Fusarium head blight in wheat and barley. This disease leads to significant losses of crop yield, and especially quality through the contamination by diverse fungal mycotoxins, which constitute a significant threat to the health of humans and animals. In recent years, high-throughput proteomics, aiming at identifying a broad spectrum of proteins with a potential role in the pathogenicity and host resistance, has become a very useful tool in plant-fungus interaction research. In this review, we describe the progress in proteomics applications toward a better understanding of F. graminearum pathogenesis, virulence, and host defense mechanisms. The contribution of proteomics to the development of crop protection strategies against this pathogen is also discussed briefly. PMID:23450732

Not all GMOs are crop plants: non-plant GMO applications in agriculture

USDA-ARS?s Scientific Manuscript database

In the time since the tools of modern biotechnology have become available, the most commonly applied and often discussed genetically modified organisms are genetically modified crop plants, although genetic engineering is also being used successfully in organisms other than plants, including bacteri...

Crop calendars for the US, USSR, and Canada in support of the early warning project

NASA Technical Reports Server (NTRS)

Hodges, T.; Sestak, M. L.; Trenchard, M. H. (Principal Investigator)

1980-01-01

New crop calendars are produced for U.S. regions where several years of periodic growth stage observations are available on a CRD basis. Preexisting crop calendars from the LACIE are also collected as are U.S. crop calendars currently being created for the Foreign Commodities Production Forecast project. For the U.S.S.R. and Canada, no new crop calendars are created because no new data are available. Instead, LACIE crop calendars are compared against simulated normal daily temperatures and against the Robertson wheat and Williams barley phenology models run on the simulated normal temperatures. Severe inconsistencies are noted and discussed. For the U.S.S.R., spring and fall planting dates can probably be estimated accurately from satellite or meteorological data. For the starter model problem, the Feyerherm spring wheat model is recommended for spring planted small grains, and the results of an analysis are presented. For fall planted small grains, use of normal planting dates supplemented by spectral observation of an early stage is recommended. The importance of nonmeteorological factors as they pertain to meteorological factors in determining fall planting is discussed. Crop calendar data available at the Johnson Space Center for the U.S., U.S.S.R., Canada, and other countries are inventoried.

The availability and economic analyses of using marginal land for bioenergy production in China

NASA Astrophysics Data System (ADS)

Yuqi, Chen; Xudong, Guo; Chunyan, Lv

2017-04-01

In recent years, China has witnessed rapid increase in the dependence of foreign oil import. In 2015, the primary energy consumption of China is 543 million tons, of which 328 million tons was imported. The total amount of imported foreign oil increased from 49.8% in 2008 to 60.41% in 2016. To address the national energy security and GHG emission reduction, China has made considerable progress in expanding renewable energy portfolio, especially liquid biofuels. However, under the pressure of high population and vulnerable food security, China's National Development and Reform Commission (NDRC) ruled that bioenergy is only allowed to be produced using non-cereal feedstock. In addition, the energy crops can only be planted on marginal land, which is the land not suitable for growing field crops due to edaphic and/or climatic limitations, and other environmental risks. Although there have been a number of studies about estimating the marginal land for energy plants' cultivation in China, as to the different definition of marginal land and land use data, the results are quite different. Furthermore, even if there is enough marginal land suitable for energy plants' cultivation, economic viability of cultivating energy plants on marginal land is critical. In order to analyze the availability and economic analyses of the marginal land for bioenergy production strategy, firstly, by using of the latest and most authoritative land use data, this study focused on the assessment of marginal land resources and bioenergy potential by planting five species of energy plants including Cassava, Jatropha curcas, Helianthus tuberous L, Pistacia chinensis, Xanthoceras sorbifolia Bunge. The results indicate that there are 289.71 million ha marginal land can be used for these five energy plants' cultivation, which can produce 24.45 million tons bioethanol and 8.77 million tons of biodiesel. Secondly, based on field survey data and literature reviews, we found that, from the farmers' perspective, low income led to none incentive of energy plants' cultivation. From the bioenergy plants' perspective, unstable supply and high cost of feedstock constrained the normal operation. In China, both energy crop' s cultivation and bioenergy production depend too much on government subsidies. It was impossible to develop bioenergy based on marginal land if only rely on the market at present.

ALAMEDA, a Structural–Functional Model for Faba Bean Crops: Morphological Parameterization and Verification

PubMed Central

RUIZ-RAMOS, MARGARITA; MÍNGUEZ, M. INÉS

2006-01-01

• Background Plant structural (i.e. architectural) models explicitly describe plant morphology by providing detailed descriptions of the display of leaf and stem surfaces within heterogeneous canopies and thus provide the opportunity for modelling the functioning of plant organs in their microenvironments. The outcome is a class of structural–functional crop models that combines advantages of current structural and process approaches to crop modelling. ALAMEDA is such a model. • Methods The formalism of Lindenmayer systems (L-systems) was chosen for the development of a structural model of the faba bean canopy, providing both numerical and dynamic graphical outputs. It was parameterized according to the results obtained through detailed morphological and phenological descriptions that capture the detailed geometry and topology of the crop. The analysis distinguishes between relationships of general application for all sowing dates and stem ranks and others valid only for all stems of a single crop cycle. • Results and Conclusions The results reveal that in faba bean, structural parameterization valid for the entire plant may be drawn from a single stem. ALAMEDA was formed by linking the structural model to the growth model ‘Simulation d'Allongement des Feuilles’ (SAF) with the ability to simulate approx. 3500 crop organs and components of a group of nine plants. Model performance was verified for organ length, plant height and leaf area. The L-system formalism was able to capture the complex architecture of canopy leaf area of this indeterminate crop and, with the growth relationships, generate a 3D dynamic crop simulation. Future development and improvement of the model are discussed. PMID:16390842

Robust Crop and Weed Segmentation under Uncontrolled Outdoor Illumination

PubMed Central

Jeon, Hong Y.; Tian, Lei F.; Zhu, Heping

2011-01-01

An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect weeds and crop plants under uncontrolled outdoor illuminations. A machine vision implementing field robot captured field images under outdoor illuminations and the image processing algorithm automatically processed them without manual adjustment. The errors of the algorithm, when processing 666 field images, ranged from 2.1 to 2.9%. The ANN correctly detected 72.6% of crop plants from the identified plants, and considered the rest as weeds. However, the ANN identification rates for crop plants were improved up to 95.1% by addressing the error sources in the algorithm. The developed weed detection and image processing algorithm provides a novel method to identify plants against soil background under the uncontrolled outdoor illuminations, and to differentiate weeds from crop plants. Thus, the proposed new machine vision and processing algorithm may be useful for outdoor applications including plant specific direct applications (PSDA). PMID:22163954

A dubious success: The NGO campaign against GMOs

PubMed Central

Paarlberg, Robert

2014-01-01

Genetically engineered agricultural crops are widely grown for animal feed (yellow corn, soybean meal) and for industrial purposes (such as cotton for fabric, or yellow corn for ethanol), but almost nobody grows GMO food staple crops. The only GMO food staple crop planted anywhere is white maize, and only in one country – the Republic of South Africa. It has been two decades now since GMO crops were first planted commercially, yet it is still not legal anywhere to plant GMO wheat or GMO rice. When it comes to GMO food crops, anti-GMO campaigners have thus won a remarkable yet dubious victory. They have not prevented rich countries from using GMO animal feed or GMO cotton, yet farmers and consumers in poor countries need increased productivity for food crops, not animal feed or industrial crops. Today's de facto global ban on GMO food crops therefore looks suspiciously like an outcome designed by the rich and for the rich, with little regard for the interests of the poor. PMID:25437241

A dubious success: the NGO campaign against GMOs.

PubMed

Paarlberg, Robert

2014-07-03

Genetically engineered agricultural crops are widely grown for animal feed (yellow corn, soybean meal) and for industrial purposes (such as cotton for fabric, or yellow corn for ethanol), but almost nobody grows GMO food staple crops. The only GMO food staple crop planted anywhere is white maize, and only in one country--the Republic of South Africa. It has been two decades now since GMO crops were first planted commercially, yet it is still not legal anywhere to plant GMO wheat or GMO rice. When it comes to GMO food crops, anti-GMO campaigners have thus won a remarkable yet dubious victory. They have not prevented rich countries from using GMO animal feed or GMO cotton, yet farmers and consumers in poor countries need increased productivity for food crops, not animal feed or industrial crops. Today's de facto global ban on GMO food crops therefore looks suspiciously like an outcome designed by the rich and for the rich, with little regard for the interests of the poor.

Rhizosphere Microbiomes Modulated by Pre-crops Assisted Plants in Defense Against Plant-Parasitic Nematodes

PubMed Central

Elhady, Ahmed; Adss, Shimaa; Hallmann, Johannes; Heuer, Holger

2018-01-01

Plant-parasitic nematodes cause considerable damage to crop plants. The rhizosphere microbiome can affect invasion and reproductive success of plant-parasitic nematodes, thus affecting plant damage. In this study, we investigated how the transplanted rhizosphere microbiome from different crops affect plant-parasitic nematodes on soybean or tomato, and whether the plant’s own microbiome from the rhizosphere protects it better than the microbiome from fallow soil. Soybean plants growing in sterilized substrate were inoculated with the microbiome extracted from the rhizosphere of soybean, maize, or tomato. Controls were inoculated with extracts from bulk soil, or not inoculated. After the microbiome was established, the root lesion nematode Pratylenchus penetrans was added. Root invasion of P. penetrans was significantly reduced on soybean plants inoculated with the microbiome from maize or soybean compared to tomato or bulk soil, or the uninoculated control. In the analogous experiment with tomato plants inoculated with either P. penetrans or the root knot nematode Meloidogyne incognita, the rhizosphere microbiomes of maize and tomato reduced root invasion by P. penetrans and M. incognita compared to microbiomes from soybean or bulk soil. Reproduction of M. incognita on tomato followed the same trend, and it was best suppressed by the tomato rhizosphere microbiome. In split-root experiments with soybean and tomato plants, a systemic effect of the inoculated rhizosphere microbiomes on root invasion of P. penetrans was shown. Furthermore, some transplanted microbiomes slightly enhanced plant growth compared to uninoculated plants. The microbiomes from maize rhizosphere and bulk soil increased the fresh weights of roots and shoots of soybean plants, and microbiomes from soybean rhizosphere and bulk soil increased the fresh weights of roots and shoots of tomato plants. Nematode invasion did not affect plant growth in these short-term experiments. In conclusion, this study highlights the importance of the rhizosphere microbiome in protecting crops against plant-parasitic nematodes. An effect of pre-crops on the rhizosphere microbiome might be harnessed to enhance the resistance of crops towards plant-parasitic nematodes. However, nematode-suppressive effects of a particular microbiome may not necessarily coincide with improvement of plant growth in the absence of plant-parasitic nematodes. PMID:29915566

Synseed technology-a complete synthesis.

PubMed

Sharma, Shiwali; Shahzad, Anwar; Teixeira da Silva, Jaime A

2013-01-01

Progress in biotechnological research over the last two decades has provided greater scope for the improvement of crops, forest trees and other important plant species. Plant propagation using synthetic seeds has opened new vistas in the field of agriculture. Synseed technology is a highly promising tool for the management of transgenic and seedless plant species, polyploid plants with elite traits and plant lines that are difficult to propagate through conventional propagation methods. Delivery of synseeds also alleviates issues like undertaking several passages for scaling up in vitro cultures as well as acclimatization to ex vitro conditions. Optimization of synchronized propagule development followed by automation of the whole process (sorting, harvesting, encapsulation and conversion) can enhance the pace of synseed production. Cryopreservation of encapsulated germplasm has now been increasingly used as an ex vitro conservation tool with the possible minimization of adverse effects of cryoprotectants and post-preservation damages. Through synseed technology, germplasm exchange between countries could be accelerated as a result of reduced plant quarantine requirements because of the aseptic condition of the plant material. Copyright © 2012 Elsevier Inc. All rights reserved.

7 CFR 319.59-1 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... processing. Hay. Host crops cut and dried for feeding to livestock. Hay cut after reaching the dough stage may contain mature kernels of the host crop. Host crops. Plants or plant parts, including grain, seed..., and a seed. Seed. Wheat (Triticum aestivum), durum wheat (Triticum durum), and triticale (Triticum...

Emerging crops in the USDA arid lands germplasm collection

USDA-ARS?s Scientific Manuscript database

The USDA National Plant Germplasm System maintains collections of several emerging crops for arid lands at the National Arid Land Plant Genetic Resources Unit in Parlier, CA (NALPGRU). The guayule, jojoba, and prickly pear collections are most active in terms of current research and crop development...

Increasing diveristy of arbuscular mycorrhizal fungi in agroecosystems using specific cover crops

USDA-ARS?s Scientific Manuscript database

Fall-planted cover crops provide a plant host for obligate symbiotic arbuscular mycorrhizal fungi (AMF) during otherwise fallow periods and thus may increase AMF numbers in agroecosystems. Increased AMF numbers should increase mycorrhizal colonization of the subsequent cash crops, which has been li...

Alternative cropping systems for sugarcane

USDA-ARS?s Scientific Manuscript database

Planting cover crops during the fallow period prior to planting sugarcane has the potential to influence not only the following sugarcane crop, but the economics of the production system as a whole. Research was conducted at the USDA, ARS, Sugarcane Research Unit at Houma, LA to determine the impac...

A National Crop Progress Monitoring System Based on NASA Earth Science Results

NASA Astrophysics Data System (ADS)

Di, L.; Yu, G.; Zhang, B.; Deng, M.; Yang, Z.

2011-12-01

Crop progress is an important piece of information for food security and agricultural commodities. Timely monitoring and reporting are mandated for the operation of agricultural statistical agencies. Traditionally, the weekly reporting issued by the National Agricultural Statistics Service (NASS) of the United States Department of Agriculture (USDA) is based on reports from the knowledgeable state and county agricultural officials and farmers. The results are spatially coarse and subjective. In this project, a remote-sensing-supported crop progress monitoring system is being developed intensively using the data and derived products from NASA Earth Observing satellites. Moderate Resolution Imaging Spectroradiometer (MODIS) Level 3 product - MOD09 (Surface Reflectance) is used for deriving daily normalized vegetation index (NDVI), vegetation condition index (VCI), and mean vegetation condition index (MVCI). Ratio change to previous year and multiple year mean can be also produced on demand. The time-series vegetation condition indices are further combined with the NASS' remote-sensing-derived Cropland Data Layer (CDL) to estimate crop condition and progress crop by crop. To facilitate the operational requirement and increase the accessibility of data and products by different users, each component of the system has being developed and implemented following open specifications under the Web Service reference model of Open Geospatial Consortium Inc. Sensor observations and data are accessed through Web Coverage Service (WCS), Web Feature Service (WFS), or Sensor Observation Service (SOS) if available. Products are also served through such open-specification-compliant services. For rendering and presentation, Web Map Service (WMS) is used. A Web-service based system is set up and deployed at dss.csiss.gmu.edu/NDVIDownload. Further development will adopt crop growth models, feed the models with remotely sensed precipitation and soil moisture information, and incorporate the model results with vegetation-index time series for crop progress stage estimation.

76 FR 37769 - Bayer CropScience LP; Availability of Petition, Plant Pest Risk Assessment, and Environmental...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service [Docket No. APHIS-2010-0102] Bayer CropScience LP; Availability of Petition, Plant Pest Risk Assessment, and Environmental Assessment... Herbicide Tolerance AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Notice. SUMMARY: We...

Plant-herbivore and plant-pollinator interactions of the developing perennial oilseed crop, Silphium integrifolium

USDA-ARS?s Scientific Manuscript database

Sampling in Kansas and North Dakota documented the plant-herbivore and plant-pollinator interactions of the developing perennial oilseed crop, Silphium integrifolium Michx. The larva of the tortricid moth, Eucosma giganteana (Riley), was the most common floret- and seed-feeding pest in Kansas, with ...

Host plant associated genetic divergence of two Diatraea spp. (Lepidoptera: Crambidae) stemborers on novel crop plants

USDA-ARS?s Scientific Manuscript database

Diatraea lineolata and Diatraea saccharalis (Lepidoptera: Crambidae) are moths with stemboring larvae that feed and develop on economically important grasses. This study investigated whether these moths have diverged from a native host plant, corn, onto introduced crop plants including sorghum, suga...

Interactive effects of pests increase seed yield.

PubMed

Gagic, Vesna; Riggi, Laura Ga; Ekbom, Barbara; Malsher, Gerard; Rusch, Adrien; Bommarco, Riccardo

2016-04-01

Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides.

The components of crop productivity: measuring and modeling plant metabolism

NASA Technical Reports Server (NTRS)

Bugbee, B.

1995-01-01

Several investigators in the CELSS program have demonstrated that crop plants can be remarkably productive in optimal environments where plants are limited only by incident radiation. Radiation use efficiencies of 0.4 to 0.7 g biomass per mol of incident photons have been measured for crops in several laboratories. Some early published values for radiation use efficiency (1 g mol-1) were inflated due to the effect of side lighting. Sealed chambers are the basic research module for crop studies for space. Such chambers allow the measurement of radiation and CO2 fluxes, thus providing values for three determinants of plant growth: radiation absorption, photosynthetic efficiency (quantum yield), and respiration efficiency (carbon use efficiency). Continuous measurement of each of these parameters over the plant life cycle has provided a blueprint for daily growth rates, and is the basis for modeling crop productivity based on component metabolic processes. Much of what has been interpreted as low photosynthetic efficiency is really the result of reduced leaf expansion and poor radiation absorption. Measurements and models of short-term (minutes to hours) and long-term (days to weeks) plant metabolic rates have enormously improved our understanding of plant environment interactions in ground-based growth chambers and are critical to understanding plant responses to the space environment.

Medicinally important secondary metabolites in recombinant microorganisms or plants: progress in alkaloid biosynthesis.

PubMed

Schäfer, Holger; Wink, Michael

2009-12-01

Plants produce a high diversity of natural products or secondary metabolites which are important for the communication of plants with other organisms. A prominent function is the protection against herbivores and/or microbial pathogens. Some natural products are also involved in defence against abiotic stress, e.g. UV-B exposure. Many of the secondary metabolites have interesting biological properties and quite a number are of medicinal importance. Because the production of the valuable natural products, such as the anticancer drugs paclitaxel, vinblastine or camptothecin in plants is a costly process, biotechnological alternatives to produce these alkaloids more economically become increasingly important. This review provides an overview of the state of art to produce alkaloids in recombinant microorganisms, such as bacteria or yeast. Some progress has been made in metabolic engineering usually employing a single recombinant alkaloid gene. More importantly, for benzylisoquinoline, monoterpene indole and diterpene alkaloids (taxanes) as well as some terpenoids and phenolics the proof of concept for production of complex alkaloids in recombinant Escherichia coli and yeast has already been achieved. In a long-term perspective, it will probably be possible to generate gene cassettes for complete pathways, which could then be used for production of valuable natural products in bioreactors or for metabolic engineering of crop plants. This will improve their resistance against herbivores and/or microbial pathogens.

Crop improvement using life cycle datasets acquired under field conditions.

PubMed

Mochida, Keiichi; Saisho, Daisuke; Hirayama, Takashi

2015-01-01

Crops are exposed to various environmental stresses in the field throughout their life cycle. Modern plant science has provided remarkable insights into the molecular networks of plant stress responses in laboratory conditions, but the responses of different crops to environmental stresses in the field need to be elucidated. Recent advances in omics analytical techniques and information technology have enabled us to integrate data from a spectrum of physiological metrics of field crops. The interdisciplinary efforts of plant science and data science enable us to explore factors that affect crop productivity and identify stress tolerance-related genes and alleles. Here, we describe recent advances in technologies that are key components for data driven crop design, such as population genomics, chronological omics analyses, and computer-aided molecular network prediction. Integration of the outcomes from these technologies will accelerate our understanding of crop phenology under practical field situations and identify key characteristics to represent crop stress status. These elements would help us to genetically engineer "designed crops" to prevent yield shortfalls because of environmental fluctuations due to future climate change.

Tillage as a tool to manage crop residue: impact on sugar beet production.

NASA Astrophysics Data System (ADS)

Hiel, Marie-Pierre; Chélin, Marie; Degrune, Florine; Parvin, Nargish; Bodson, Bernard

2015-04-01

Crop residues and plant cover represent a pool of organic matter that can be used either to restore organic matter in soils, and therefore maintain soil fertility, or that can be valorized outside of the field (e.g. energy production). However, it is crucial that the exportation of residues is not done to the detriment of the system sustainability. Three long term experiments have been settled in the loamy region in Belgium. All of them are designed to study the effect of residues management by several tillage systems (conventional plowing versus reduced tillage) on the whole soil-water-plant system. SOLRESIDUS is a field experiment where we study the impact of crop residue management while in SOLCOUVERT and SOLCOUVERT-BIS, we study the impact of cover crop management. SOLRESIDUS was started in 2008. In this field, four contrasted crop residues managements are tested in order to contrast as much as possible the responses from the soil-water plant system. Two practices characterize the four modalities: soil tillage (ploughing at 25 cm depth or reduce tillage at 10 cm max) and residue management (exportation or restitution). SOLCOUVERT and SOLCOUVERT-BIS were started in 2012 and 2013 respectively. In those fields cover crop management is also diverse: destruction of the cover crop by winter ploughing, spring ploughing, strip tillage (with a chemical destruction if needed) or shallow tillage (with a decompaction before cover crop sowing). Although although the overall project aims at studying the impact of management on the whole soil-water-plant system, here we will only present the results concerning crop production (sugar beet) in SOLCOUVERT experiments. The presented data will include germination rate, crop development (biomass quantification and BBCH stages) weeds population, disease occurrence, pest occurrences, nitrogen uptake by plants, quality and quantity of harvested products.

Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe.

PubMed

Hass, Annika L; Kormann, Urs G; Tscharntke, Teja; Clough, Yann; Baillod, Aliette Bosem; Sirami, Clélia; Fahrig, Lenore; Martin, Jean-Louis; Baudry, Jacques; Bertrand, Colette; Bosch, Jordi; Brotons, Lluís; Burel, Françoise; Georges, Romain; Giralt, David; Marcos-García, María Á; Ricarte, Antonio; Siriwardena, Gavin; Batáry, Péter

2018-02-14

Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish ( Raphanus sativus ), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management. © 2018 The Author(s).

Simulating crop growth with Expert-N-GECROS under different site conditions in Southwest Germany

NASA Astrophysics Data System (ADS)

Poyda, Arne; Ingwersen, Joachim; Demyan, Scott; Gayler, Sebastian; Streck, Thilo

2016-04-01

When feedbacks between the land surface and the atmosphere are investigated by Atmosphere-Land surface-Crop-Models (ALCM) it is fundamental to accurately simulate crop growth dynamics as plants directly influence the energy partitioning at the plant-atmosphere interface. To study both the response and the effect of intensive agricultural crop production systems on regional climate change in Southwest Germany, the crop growth model GECROS (YIN & VAN LAAR, 2005) was calibrated based on multi-year field data from typical crop rotations in the Kraichgau and Swabian Alb regions. Additionally, the SOC (soil organic carbon) model DAISY (MÜLLER et al., 1998) was implemented in the Expert-N model tool (ENGEL & PRIESACK, 1993) and combined with GECROS. The model was calibrated based on a set of plant (BBCH, LAI, plant height, aboveground biomass, N content of biomass) and weather data for the years 2010 - 2013 and validated with the data of 2014. As GECROS adjusts the root-shoot partitioning in response to external conditions (water, nitrogen, CO2), it is suitable to simulate crop growth dynamics under changing climate conditions and potentially more frequent stress situations. As C and N pools and turnover rates in soil as well as preceding crop effects were expected to considerably influence crop growth, the model was run in a multi-year, dynamic way. Crop residues and soil mineral N (nitrate, ammonium) available for the subsequent crop were accounted for. The model simulates growth dynamics of winter wheat, winter rape, silage maize and summer barley at the Kraichgau and Swabian Alb sites well. The Expert-N-GECROS model is currently parameterized for crops with potentially increasing shares in future crop rotations. First results will be shown.

Unlimited Thirst for Genome Sequencing, Data Interpretation, and Database Usage in Genomic Era: The Road towards Fast-Track Crop Plant Improvement

PubMed Central

Govindaraj, Mahalingam

2015-01-01

The number of sequenced crop genomes and associated genomic resources is growing rapidly with the advent of inexpensive next generation sequencing methods. Databases have become an integral part of all aspects of science research, including basic and applied plant and animal sciences. The importance of databases keeps increasing as the volume of datasets from direct and indirect genomics, as well as other omics approaches, keeps expanding in recent years. The databases and associated web portals provide at a minimum a uniform set of tools and automated analysis across a wide range of crop plant genomes. This paper reviews some basic terms and considerations in dealing with crop plant databases utilization in advancing genomic era. The utilization of databases for variation analysis with other comparative genomics tools, and data interpretation platforms are well described. The major focus of this review is to provide knowledge on platforms and databases for genome-based investigations of agriculturally important crop plants. The utilization of these databases in applied crop improvement program is still being achieved widely; otherwise, the end for sequencing is not far away. PMID:25874133

Application of agricultural biotechnology to improve food nutrition and healthcare products.

PubMed

Sun, Samuel S M

2008-01-01

Crop plants provide essential food nutrients to humans and livestock, including carbohydrates, lipids, proteins, minerals and vitamins, directly or indirectly. The level and composition of food nutrients vary significantly in different food crops. As a result, plant foods are often deficient in certain nutrient components. Relying on a single food crop as source of nutrients thus will not achieve a balanced diet and results in malnutrition and deficiency diseases, especially in the developing countries, due mainly to poverty. The development and application of biotechnology offers opportunities and novel possibilities to enhance the nutritional quality of crops, particularly when the necessary genetic variability is not available. While initial emphasis of agricultural biotechnology has been placed on input traits of crops such as herbicide tolerance, insect resistance and virus resistance, increasing effort and promising proof-of-concept products have been made in output traits including enhancing the nutritional quality of crops since 1990s. Advancements in plant transformation and transgene expression also allow the use of plants as bioreactors to produce a variety of bio-products at large scale and low cost. Many proof-of-concept plant-derived healthcare products have been generated and several commercialized.

Development and application of transgenic technologies in cassava.

PubMed

Taylor, Nigel; Chavarriaga, Paul; Raemakers, Krit; Siritunga, Dimuth; Zhang, Peng

2004-11-01

The capacity to integrate transgenes into the tropical root crop cassava (Manihot esculenta Crantz) is now established and being utilized to generate plants expressing traits of agronomic interest. The tissue culture and gene transfer systems currently employed to produce these transgenic cassava have improved significantly over the past 5 years and are assessed and compared in this review. Programs are underway to develop cassava with enhanced resistance to viral diseases and insects pests, improved nutritional content, modified and increased starch metabolism and reduced cyanogenic content of processed roots. Each of these is described individually for the underlying biology the molecular strategies being employed and progress achieved towards the desired product. Important advances have occurred, with transgenic plants from several laboratories being prepared for field trails.

Removal of trace metals by Sorghum bicolor and Helianthus annuus in a site polluted by industrial wastes: a field experience.

PubMed

Marchiol, L; Fellet, G; Perosa, D; Zerbi, G

2007-05-01

Using the perspective of full scale application of phytoremediation techniques, research is focusing on the optimization of agronomic practices. Two annual high biomass yield crops, Sorghum bicolor and Helianthus annuus, were grown in a polymetallic soil. The experimental site, polluted by pyrite cinders, is located in an industrial site that has been listed in the clean-up national priority list since 2001. Specific aims of this work were to observe the concentration of metals in plants during the crop cycle and to establish the amount of metal removed by the crops. The field trial, arranged in a randomized block design, started in 2005. The concentrations of heavy metals in the soil were: As 309, Cd 4.29, Co 50.9, Cu 1527 and Zn 980mg kg(-1). The crops grown on the polluted soil received mineral fertilization (Fert) and organic amendment (Org), while plants in control soil (Ctrl) did not receive anything. The plots were watered during the crop cycle during two drought periods, using a sprinkler irrigation system. The phytoextraction potential of crops was estimated during the whole growth cycle and the plant biomass that was collected in each sampling date was ICP-analyzed. Plant-biomass growth curves were obtained. The concentrations of the metals in the shoots and in the total plant biomass were recorded. Finally, the metal removal was calculated for the harvestable parts of the crops. The amelioration of the nutritive status of the substrate that resulted, was highly effective for the biomass yield. However, fertilization and soil amendment did not heighten the concentration of metals in the harvestable tissue of the plants during the crop cycle. In some cases, organic matter appeared to bind the elements making them less available for the plants. The evaluation of the potential of phytoremediation of our plants compared to other crops in terms of metal removal was positive. Our results of metal removal are consistent with the results from other in situ experiments. The Zn removal by S. bicolor and H. annuus reached about 2000g ha(-1) and 1000g ha(-1), respectively.

Utilization of urea, ammonia, nitrite, and nitrate by crop plants in a Controlled Ecological Life Support System (CELSS)

NASA Technical Reports Server (NTRS)

Huffaker, R. C.; Rains, D. W.; Qualset, C. O.

1982-01-01

The utilization of nitrogen compounds by crop plants is studied. The selection of crop varieties for efficient production using urea, ammonia, nitrite, and nitrate, and the assimilation of mixed nitrogen sources by cereal leaves and roots are discussed.

7 CFR 319.59-1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... triticale (Triticum aestivum X Secale cereale) used for consumption or processing. Hay. Host crops cut and... host crop. Host crops. Plants or plant parts, including grain, seed, or hay, of wheat (Triticum..., a vine, a cutting, a graft, a scion, a bud, a bulb, a root, and a seed. Seed. Wheat (Triticum...

7 CFR 319.59-1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... triticale (Triticum aestivum X Secale cereale) used for consumption or processing. Hay. Host crops cut and... host crop. Host crops. Plants or plant parts, including grain, seed, or hay, of wheat (Triticum..., a vine, a cutting, a graft, a scion, a bud, a bulb, a root, and a seed. Seed. Wheat (Triticum...

7 CFR 319.59-1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... triticale (Triticum aestivum X Secale cereale) used for consumption or processing. Hay. Host crops cut and... host crop. Host crops. Plants or plant parts, including grain, seed, or hay, of wheat (Triticum..., a vine, a cutting, a graft, a scion, a bud, a bulb, a root, and a seed. Seed. Wheat (Triticum...

7 CFR 319.59-1 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... triticale (Triticum aestivum X Secale cereale) used for consumption or processing. Hay. Host crops cut and... host crop. Host crops. Plants or plant parts, including grain, seed, or hay, of wheat (Triticum..., a vine, a cutting, a graft, a scion, a bud, a bulb, a root, and a seed. Seed. Wheat (Triticum...

Dynamics of plant nutrients, utilization and uptake, and soil microbial community in crops under ambient and elevated carbon dioxide

USDA-ARS?s Scientific Manuscript database

In natural settings such as under field conditions, the plant available soil nutrients in conjunction with other environmental factors such as, solar radiation, temperature, precipitation, and atmospheric carbon dioxide (CO2) concentration determine crop adaptation and productivity. Therefore, crop...

40 CFR 80.1401 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and/or the distillers grains and solubles produced by a dry mill corn ethanol plant, most often by... biomass includes any portion of a crop or crop plant. Cropland is land used for production of crops for... bred to maximize cellulosic rather than sugar content. For the purposes of this section, energy cane...

40 CFR 80.1401 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and/or the distillers grains and solubles produced by a dry mill corn ethanol plant, most often by... biomass includes any portion of a crop or crop plant. Cropland is land used for production of crops for... bred to maximize cellulosic rather than sugar content. For the purposes of this section, energy cane...

77 FR 13961 - Common Crop Insurance Regulations; Onion Crop Insurance Provisions

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-08

... good farming practices, as applicable, must be exhausted before any action against FCIC for judicial... for all producers regardless of the size of their farming operation. For instance, all producers are... practices of planting such as direct seeded and transplanted. The onion crop is planted earlier for the...

NON-TARGET AND ECOSYSTEM IMPACTS FROM GENETICALLY MODIFIED CROPS CONTAINING PLANT INCORPORATED PROTECTANTS (PIPS)

EPA Science Inventory

The risk of unintended and unexpected adverse impacts on non-target organisms and ecosystems is a key issue in environmental risk assessment of PIP crop plants. While there has been considerable examination of the effects of insect resistant crops on certain non-target organisms...

Bacillus: A Biological Tool for Crop Improvement through Bio-Molecular Changes in Adverse Environments

PubMed Central

Radhakrishnan, Ramalingam; Hashem, Abeer; Abd_Allah, Elsayed F.

2017-01-01

Crop productivity is affected by environmental and genetic factors. Microbes that are beneficial to plants are used to enhance the crop yield and are alternatives to chemical fertilizers and pesticides. Pseudomonas and Bacillus species are the predominant plant growth-promoting bacteria. The spore-forming ability of Bacillus is distinguished from that of Pseudomonas. Members of this genus also survive for a long time under unfavorable environmental conditions. Bacillus spp. secrete several metabolites that trigger plant growth and prevent pathogen infection. Limited studies have been conducted to understand the physiological changes that occur in crops in response to Bacillus spp. to provide protection against adverse environmental conditions. This review describes the current understanding of Bacillus-induced physiological changes in plants as an adaptation to abiotic and biotic stresses. During water scarcity, salinity and heavy metal accumulate in soil, Bacillus spp. produce exopolysaccharides and siderophores, which prevent the movement of toxic ions and adjust the ionic balance and water transport in plant tissues while controlling the pathogenic microbial population. In addition, the synthesis of indole-3-acetic acid, gibberellic acid and1-aminocyclopropane-1-carboxylate (ACC) deaminase by Bacillus regulates the intracellular phytohormone metabolism and increases plant stress tolerance. Cell-wall-degrading substances, such as chitosanase, protease, cellulase, glucanase, lipopeptides and hydrogen cyanide from Bacillus spp. damage the pathogenic bacteria, fungi, nematodes, viruses and pests to control their populations in plants and agricultural lands. The normal plant metabolism is affected by unfavorable environmental stimuli, which suppress crop growth and yield. Abiotic and biotic stress factors that have detrimental effects on crops are mitigated by Bacillus-induced physiological changes, including the regulation of water transport, nutrient up-take and the activation of the antioxidant and defense systems. Bacillus association stimulates plant immunity against stresses by altering stress-responsive genes, proteins, phytohormones and related metabolites. This review describes the beneficial effect of Bacillus spp. on crop plants, which improves plant productivity under unfavorable climatic conditions, and the current understanding of the mitigation mechanism of Bacillus spp. in stress-tolerant and/or stress-resistant plants. PMID:28932199

Bacillus: A Biological Tool for Crop Improvement through Bio-Molecular Changes in Adverse Environments.

PubMed

Radhakrishnan, Ramalingam; Hashem, Abeer; Abd Allah, Elsayed F

2017-01-01

Crop productivity is affected by environmental and genetic factors. Microbes that are beneficial to plants are used to enhance the crop yield and are alternatives to chemical fertilizers and pesticides. Pseudomonas and Bacillus species are the predominant plant growth-promoting bacteria. The spore-forming ability of Bacillus is distinguished from that of Pseudomonas . Members of this genus also survive for a long time under unfavorable environmental conditions. Bacillus spp. secrete several metabolites that trigger plant growth and prevent pathogen infection. Limited studies have been conducted to understand the physiological changes that occur in crops in response to Bacillus spp. to provide protection against adverse environmental conditions. This review describes the current understanding of Bacillus -induced physiological changes in plants as an adaptation to abiotic and biotic stresses. During water scarcity, salinity and heavy metal accumulate in soil, Bacillus spp. produce exopolysaccharides and siderophores, which prevent the movement of toxic ions and adjust the ionic balance and water transport in plant tissues while controlling the pathogenic microbial population. In addition, the synthesis of indole-3-acetic acid, gibberellic acid and1-aminocyclopropane-1-carboxylate (ACC) deaminase by Bacillus regulates the intracellular phytohormone metabolism and increases plant stress tolerance. Cell-wall-degrading substances, such as chitosanase, protease, cellulase, glucanase, lipopeptides and hydrogen cyanide from Bacillus spp. damage the pathogenic bacteria, fungi, nematodes, viruses and pests to control their populations in plants and agricultural lands. The normal plant metabolism is affected by unfavorable environmental stimuli, which suppress crop growth and yield. Abiotic and biotic stress factors that have detrimental effects on crops are mitigated by Bacillus -induced physiological changes, including the regulation of water transport, nutrient up-take and the activation of the antioxidant and defense systems. Bacillus association stimulates plant immunity against stresses by altering stress-responsive genes, proteins, phytohormones and related metabolites. This review describes the beneficial effect of Bacillus spp. on crop plants, which improves plant productivity under unfavorable climatic conditions, and the current understanding of the mitigation mechanism of Bacillus spp. in stress-tolerant and/or stress-resistant plants.

A proposal to demonstrate production of salad crops in the Space Station Mockup facility with particular attention to space, energy, and labor constraints

NASA Technical Reports Server (NTRS)

Brooks, Carolyn

1992-01-01

This research has continued along two lines, one at Marshall Space Flight Center with Salad Machine Rack development and the design and construction of a mockup for placement in the Huntsville Space Station Freedom mockup. The second avenue of research has addressed issues of relevance to the operation of the Salad Machine and Bioregenerative systems. These issues include plant species compatibility when grown on shared hydroponic systems and microbial populations of mixed species hydroponic systems. Significant progress is reported.

Nutritionally enhanced crops and food security: scientific achievements versus political expediency.

PubMed

Farre, Gemma; Twyman, Richard M; Zhu, Changfu; Capell, Teresa; Christou, Paul

2011-04-01

Genetic engineering (GE) is one of a raft of strategies that can be used to tackle malnutrition. Recent scientific advances have shown that multiple deficiencies can be tackled simultaneously using engineered plant varieties containing high levels of different minerals and organic nutrients. However, the impact of this progress is being diluted by the unwillingness of politicians to see beyond immediate popular support, favoring political expediency over controversial but potentially life-saving decisions based on rational scientific evidence. Copyright © 2010 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, G.K.

ORNL, through The Consortium for Research on Enhancing Carbon Sequestration in Terrestrial Ecosystems (CSiTE), collaborated with The Village Botanica, Inc. (VB) on a project investigating carbon sequestration in soils and commercial products from a new sustainable crop developed from perennial Hibiscus spp. Over 500 pre-treated samples were analyzed for soil carbon content. ORNL helped design a sampling scheme for soils during the planting phase of the project. Samples were collected and prepared by VB and analyzed for carbon content by ORNL. The project did not progress to a Phase II proposal because VB declined to prepare the required proposal.

Plastid biotechnology for crop production: present status and future perspectives

PubMed Central

Daniell, Henry

2012-01-01

The world population is expected to reach an estimated 9.2 billion by 2050. Therefore, food production globally has to increase by 70% in order to feed the world, while total arable land, which has reached its maximal utilization, may even decrease. Moreover, climate change adds yet another challenge to global food security. In order to feed the world in 2050, biotechnological advances in modern agriculture are essential. Plant genetic engineering, which has created a new wave of global crop production after the first green revolution, will continue to play an important role in modern agriculture to meet these challenges. Plastid genetic engineering, with several unique advantages including transgene containment, has made significant progress in the last two decades in various biotechnology applications including development of crops with high levels of resistance to insects, bacterial, fungal and viral diseases, different types of herbicides, drought, salt and cold tolerance, cytoplasmic male sterility, metabolic engineering, phytoremediation of toxic metals and production of many vaccine antigens, biopharmaceuticals and biofuels. However, useful traits should be engineered via chloroplast genomes of several major crops. This review provides insight into the current state of the art of plastid engineering in relation to agricultural production, especially for engineering agronomic traits. Understanding the bottleneck of this technology and challenges for improvement of major crops in a changing climate are discussed. PMID:21437683

Data Mining for Forecasting Mississippi Cropland Data Layers

NASA Astrophysics Data System (ADS)

Shore, F. L.; Gregory, T. L.

2011-12-01

In 1999, Mississippi became an early adopter of the National Agricultural Statistics Service (NASS) Cropland Data Layer (CDL) program. With the support of the NASS Spatial Analysis Research Section (SARS), we have progressed from an annual crop picture to a pixel by pixel history of Mississippi farming. Much of our early work for Mississippi agriculture is now easily provided from the web based application CropScape, released by SARS in 2011. In this study, pixel history data from CDLs has been mined to give forecasts of Mississippi crop acres. Traditionally, such agricultural data mining emphasizes the trends of early adopters driven by factors such as global warming, technology, practices, or the marketplace. These studies provide forecasted CDL products produced using See5° and Imagine°, the same software used in Mississippi CDL production since 2006. Mississippi CDL forecasts were made using historical information available as soon as the CDL for the previous year was completed. For example, the CDL forecast for winter wheat, produced at a date when winter wheat was planted but not most crops, gave results of 104.6 +/- 5.4% of the official NASS estimates for winter wheat for the years 2009-2011. In 2012, all of the states of the contiguous US will have the historical CDL data to do this type of study. A CDL forecast is proposed as a useful addition to CropScape.

Time interval between cover crop termination and planting influences corn seedling disease, plant growth, and yield

USDA-ARS?s Scientific Manuscript database

Experiments were established in controlled and field environment to evaluate the effect of time intervals between cereal rye cover crop termination and corn planting on corn seedling disease, corn growth, and grain yield in 2014 and 2015. Rye termination dates ranged from 25 days before planting (DB...

Crops in silico: A community wide multi-scale computational modeling framework of plant canopies

NASA Astrophysics Data System (ADS)

Srinivasan, V.; Christensen, A.; Borkiewic, K.; Yiwen, X.; Ellis, A.; Panneerselvam, B.; Kannan, K.; Shrivastava, S.; Cox, D.; Hart, J.; Marshall-Colon, A.; Long, S.

2016-12-01

Current crop models predict a looming gap between supply and demand for primary foodstuffs over the next 100 years. While significant yield increases were achieved in major food crops during the early years of the green revolution, the current rates of yield increases are insufficient to meet future projected food demand. Furthermore, with projected reduction in arable land, decrease in water availability, and increasing impacts of climate change on future food production, innovative technologies are required to sustainably improve crop yield. To meet these challenges, we are developing Crops in silico (Cis), a biologically informed, multi-scale, computational modeling framework that can facilitate whole plant simulations of crop systems. The Cis framework is capable of linking models of gene networks, protein synthesis, metabolic pathways, physiology, growth, and development in order to investigate crop response to different climate scenarios and resource constraints. This modeling framework will provide the mechanistic details to generate testable hypotheses toward accelerating directed breeding and engineering efforts to increase future food security. A primary objective for building such a framework is to create synergy among an inter-connected community of biologists and modelers to create a realistic virtual plant. This framework advantageously casts the detailed mechanistic understanding of individual plant processes across various scales in a common scalable framework that makes use of current advances in high performance and parallel computing. We are currently designing a user friendly interface that will make this tool equally accessible to biologists and computer scientists. Critically, this framework will provide the community with much needed tools for guiding future crop breeding and engineering, understanding the emergent implications of discoveries at the molecular level for whole plant behavior, and improved prediction of plant and ecosystem responses to the environment.

Bamboo vs. crops: an integrated emergy and economic evaluation of using bamboo to replace crops in south Sichuan Province, China.

PubMed

Lu, Hong-Fang; Cai, Chun-Ju; Zeng, Xian-Shu; Campbell, Daniel E; Fan, Shao-Hui; Liu, Guang-Lu

2018-03-10

Based on long-term monitoring conducted in Chang-ning county, a pilot site of the 'Grain for Green Program' (GFGP), an integrated emergy and economic method was applied to evaluate the dynamic ecological-economic performance of 3 kinds of bamboo systems planted on sloping farmland. The results confirmed the positive effects of all 3 kinds of bamboo systems on water conservation and soil erosion control. The benefits gained progressively increased during the first 8 years after conversion, going from 4639 to 16127 EMyuan/ha/yr on average. All three bamboo plantations were much more sustainable than common agricultural crops planted on sloping land (CP) on both the short and long-term scales with their Emergy Sustainability Index (ESI) and Emergy Index for Sustainable Development (EISD), respectively, being 14.07-325.71 and 80.35-265.80 times that of CP. However, all 3 bamboo plantations had a Net Economic Benefit (NEB) less than that of CP during the first 8 years after conversion. Even with the government-mandated ecological compensation applied, the annual NEB EC s of the Bambusa rigida (BR) and Phyllostachys pubescense (PP) plantations were, respectively, 3922.03 and 7422.77 yuan/ha/yr lower than the NEB of CP. Emergy-based evaluation of ecosystem services provides an objective reference for applying ecological compensation in strategy-making, but it cannot wholly solve the economic viability problem faced by all bamboo plantations. Inter-planting annual herbs or edible fungus, such as Dictyophora echinovolvata , within bamboo forests, especially in young bamboo plantations, might be a direction for optimizing bamboo cultivation that would improve its economic viability.

RNA interference technology in crop protection against arthropod pests, pathogens and nematodes.

PubMed

Zotti, Moises; Dos Santos, Ericmar Avila; Cagliari, Deise; Christiaens, Olivier; Taning, Clauvis Nji Tizi; Smagghe, Guy

2018-06-01

Scientists have made significant progress in understanding and unraveling several aspects of double-stranded RNA (dsRNA)-mediated gene silencing during the last two decades. Now that the RNA interference (RNAi) mechanism is well understood, it is time to consider how to apply the acquired knowledge to agriculture and crop protection. Some RNAi-based products are already available for farmers and more are expected to reach the market soon. Tailor-made dsRNA as an active ingredient for biopesticide formulations is considered a raw material that can be used for diverse purposes, from pest control and bee protection against viruses to pesticide resistance management. The RNAi mechanism works at the messenger RNA (mRNA) level, exploiting a sequence-dependent mode of action, which makes it unique in potency and selectivity compared with conventional agrochemicals. Furthermore, the use of RNAi in crop protection can be achieved by employing plant-incorporated protectants through plant transformation, but also by non-transformative strategies such as the use of formulations of sprayable RNAs as direct control agents, resistance factor repressors or developmental disruptors. In this review, RNAi is presented in an agricultural context (discussing products that have been launched on the market or will soon be available), and we go beyond the classical presentation of successful examples of RNAi in pest-insect control and comprehensively explore its potential for the control of plant pathogens, nematodes and mites, and to fight against diseases and parasites in beneficial insects. Moreover, we also discuss its use as a repressor for the management of pesticide-resistant weeds and insects. Finally, this review reports on the advances in non-transformative dsRNA delivery and the production costs of dsRNA, and discusses environmental considerations. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Risk assessment of genetically engineered crops: fitness effects of virus-resistance transgenes in wild Cucurbita pepo.

PubMed

Laughlin, Karen D; Power, Alison G; Snow, Allison A; Spencer, Lawrence J

2009-07-01

The development of crops genetically engineered for pathogen resistance has raised concerns that crop-to-wild gene flow could release wild or weedy relatives from regulation by the pathogens targeted by the transgenes that confer resistance. Investigation of these risks has also raised questions about the impact of gene flow from conventional crops into wild plant populations. Viruses in natural plant populations can play important roles in plant fecundity and competitive interactions. Here, we show that virus-resistance transgenes and conventional crop genes can increase fecundity of wild plants under virus pressure. We asked how gene flow from a cultivated squash (Cucurbita pepo) engineered for virus resistance would affect the fecundity of wild squash (C. pepo) in the presence and absence of virus pressure. A transgenic squash cultivar was crossed and backcrossed with wild C. pepo from Arkansas. Wild C. pepo, transgenic backcross plants, and non-transgenic backcross plants were compared in field plots in Ithaca, New York, USA. The second and third generations of backcrosses (BC2 and BC3) were used in 2002 and 2003, respectively. One-half of the plants were inoculated with zucchini yellow mosaic virus (ZYMV), and one-half of the plants were maintained as healthy controls. Virus pressure dramatically decreased the fecundity of wild C. pepo plants and non-transgenic backcross plants relative to transgenic backcross plants, which showed continued functioning of the virus-resistance transgene. In 2002, non-transgenic backcross fecundity was slightly higher than wild C. pepo fecundity under virus pressure, indicating a possible benefit of conventional crop alleles, but they did not differ in 2003 when fecundity was lower in both groups. We detected no fitness costs of the transgene in the absence of the virus. If viruses play a role in the population dynamics of wild C. pepo, we predict that gene flow from transgenic, virus-resistant squash and, to a much lesser extent, conventionally bred squash would increase C. pepo fecundity. Studies such as this one, in combination with documentation of the probability of crop-to-wild gene flow and surveys of virus incidence in wild populations, can provide a solid basis for environmental risk assessments of crops genetically engineered for virus resistance.

Piriformospora indica: Potential and Significance in Plant Stress Tolerance

PubMed Central

Gill, Sarvajeet S.; Gill, Ritu; Trivedi, Dipesh K.; Anjum, Naser A.; Sharma, Krishna K.; Ansari, Mohammed W.; Ansari, Abid A.; Johri, Atul K.; Prasad, Ram; Pereira, Eduarda; Varma, Ajit; Tuteja, Narendra

2016-01-01

Owing to its exceptional ability to efficiently promote plant growth, protection and stress tolerance, a mycorrhiza like endophytic Agaricomycetes fungus Piriformospora indica has received a great attention over the last few decades. P. indica is an axenically cultiviable fungus which exhibits its versatility for colonizing/hosting a broad range of plant species through directly manipulating plant hormone-signaling pathway during the course of mutualism. P. indica-root colonization leads to a better plant performance in all respect, including enhanced root proliferation by indole-3-acetic acid production which in turn results into better nutrient-acquisition and subsequently to improved crop growth and productivity. Additionally, P. indica can induce both local and systemic resistance to fungal and viral plant diseases through signal transduction. P. indica-mediated stimulation in antioxidant defense system components and expressing stress-related genes can confer crop/plant stress tolerance. Therefore, P. indica can biotize micropropagated plantlets and also help these plants to overcome transplantation shock. Nevertheless, it can also be involved in a more complex symbiotic relationship, such as tripartite symbiosis and can enhance population dynamic of plant growth promoting rhizobacteria. In brief, P. indica can be utilized as a plant promoter, bio-fertilizer, bioprotector, bioregulator, and biotization agent. The outcome of the recent literature appraised herein will help us to understand the physiological and molecular bases of mechanisms underlying P. indica-crop plant mutual relationship. Together, the discussion will be functional to comprehend the usefulness of crop plant-P. indica association in both achieving new insights into crop protection/improvement as well as in sustainable agriculture production. PMID:27047458

Impact of vetch cover crop on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia

NASA Astrophysics Data System (ADS)

Demelash, Nigus; Klik, Andreas; Holzmann, Hubert; Ziadat, Feras; Strohmeier, Stefan; Bayu, Wondimu; Zucca, Claudio; Abera, Atikilt

2016-04-01

Cover crops improve the sustainability and quality of both natural system and agro ecosystem. In Gumara-Maksegnit watershed which is located in Lake Tana basin, farmers usually use fallow during the rainy season for the preceding chickpea production system. The fallowing period can lead to soil erosion and nutrient losses. A field experiment was conducted during growing seasons 2014 and 2015 to evaluate the effect of cover crops on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia. The plot experiment contained four treatments arranged in Randomized Complete Block Design with three replications: 1) Control plot (Farmers' practice: fallowing- without cover crop), 2) Chickpea planted with Di-ammonium phosphate (DAP) fertilizer with 46 k ha-1 P2O5 and 23 k ha-1 nitrogen after harvesting vetch cover crop, 3) Chick pea planted with vetch cover crop incorporated with the soil as green manure without fertilizer, 4) Chick pea planted with vetch cover crop and incorporated with the soil as green manure and with 23 k ha-1 P2O5 and 12.5 k ha-1 nitrogen. Each plot with an area of 36 m² was equipped with a runoff monitoring system. Vetch (Vicia sativa L.) was planted as cover crop at the onset of the rain in June and used as green manure. The results of the experiment showed statistically significant (P < 0.05) differences on the number of pods per plant, above ground biomass and grain yield of chick pea. However, there was no statistically significant difference (P > 0.05) on average plant height, average number of branches and hundred seed weight. Similarly, the results indicated that cover crop has a clear impact on runoff volume and sediment loss. Plots with vetch cover crop reduce the average runoff by 65% and the average soil loss decreased from 15.7 in the bare land plot to 8.6 t ha-1 with plots covered by vetch. In general, this result reveales that the cover crops, especially vetch, can be used to improve chickpea grain yield in addition to reduce soil erosion in the watershed.

Plant-parasitic nematodes in Hawaiian agriculture

USDA-ARS?s Scientific Manuscript database

Hawaii’s diverse and mild climate allows for the cultivation of many crops. The introduction of each crop plant brought along its associated nematode pests. These plant-parasitic nematodes became established and are now endemic to the islands. Plantation agriculture determined the major nematode ...

Crop 3D-a LiDAR based platform for 3D high-throughput crop phenotyping.

PubMed

Guo, Qinghua; Wu, Fangfang; Pang, Shuxin; Zhao, Xiaoqian; Chen, Linhai; Liu, Jin; Xue, Baolin; Xu, Guangcai; Li, Le; Jing, Haichun; Chu, Chengcai

2018-03-01

With the growing population and the reducing arable land, breeding has been considered as an effective way to solve the food crisis. As an important part in breeding, high-throughput phenotyping can accelerate the breeding process effectively. Light detection and ranging (LiDAR) is an active remote sensing technology that is capable of acquiring three-dimensional (3D) data accurately, and has a great potential in crop phenotyping. Given that crop phenotyping based on LiDAR technology is not common in China, we developed a high-throughput crop phenotyping platform, named Crop 3D, which integrated LiDAR sensor, high-resolution camera, thermal camera and hyperspectral imager. Compared with traditional crop phenotyping techniques, Crop 3D can acquire multi-source phenotypic data in the whole crop growing period and extract plant height, plant width, leaf length, leaf width, leaf area, leaf inclination angle and other parameters for plant biology and genomics analysis. In this paper, we described the designs, functions and testing results of the Crop 3D platform, and briefly discussed the potential applications and future development of the platform in phenotyping. We concluded that platforms integrating LiDAR and traditional remote sensing techniques might be the future trend of crop high-throughput phenotyping.

Optimization on Paddy Crops in Central Java (with Solver, SVD on Least Square and ACO (Ant Colony Algorithm))

NASA Astrophysics Data System (ADS)

Parhusip, H. A.; Trihandaru, S.; Susanto, B.; Prasetyo, S. Y. J.; Agus, Y. H.; Simanjuntak, B. H.

2017-03-01

Several algorithms and objective functions on paddy crops have been studied to get optimal paddy crops in Central Java based on the data given from Surakarta and Boyolali. The algorithms are linear solver, least square and Ant Colony Algorithms (ACO) to develop optimization procedures on paddy crops modelled with Modified GSTAR (Generalized Space-Time Autoregressive) and nonlinear models where the nonlinear models are quadratic and power functions. The studied data contain paddy crops from Surakarta and Boyolali determining the best period of planting in the year 1992-2012 for Surakarta where 3 periods for planting are known and the optimal amount of paddy crops in Boyolali in the year 2008-2013. Having these analyses may guide the local agriculture government to give a decision on rice sustainability in its region. The best period for planting in Surakarta is observed, i.e. the best period is in September-December based on the data 1992-2012 by considering the planting area, the cropping area, and the paddy crops are the most important factors to be taken into account. As a result, we can refer the paddy crops in this best period (about 60.4 thousand tons per year) as the optimal results in 1992-2012 where the used objective function is quadratic. According to the research, the optimal paddy crops in Boyolali about 280 thousand tons per year where the studied factors are the amount of rainfalls, the harvested area and the paddy crops in 2008-2013. In this case, linear and power functions are studied to be the objective functions. Compared to all studied algorithms, the linear solver is still recommended to be an optimization tool for a local agriculture government to predict paddy crops in future.

Induction of abiotic stress tolerance in plants by endophytic microbes.

PubMed

Lata, R; Chowdhury, S; Gond, S K; White, J F

2018-04-01

Endophytes are micro-organisms including bacteria and fungi that survive within healthy plant tissues and promote plant growth under stress. This review focuses on the potential of endophytic microbes that induce abiotic stress tolerance in plants. How endophytes promote plant growth under stressful conditions, like drought and heat, high salinity and poor nutrient availability will be discussed. The molecular mechanisms for increasing stress tolerance in plants by endophytes include induction of plant stress genes as well as biomolecules like reactive oxygen species scavengers. This review may help in the development of biotechnological applications of endophytic microbes in plant growth promotion and crop improvement under abiotic stress conditions. Increasing human populations demand more crop yield for food security while crop production is adversely affected by abiotic stresses like drought, salinity and high temperature. Development of stress tolerance in plants is a strategy to cope with the negative effects of adverse environmental conditions. Endophytes are well recognized for plant growth promotion and production of natural compounds. The property of endophytes to induce stress tolerance in plants can be applied to increase crop yields. With this review, we intend to promote application of endophytes in biotechnology and genetic engineering for the development of stress-tolerant plants. © 2018 The Society for Applied Microbiology.

THE APPLICATION OF NUCLEAR ENERGY TO AGRICULTURE. Annual Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moh, C.C.

1963-07-01

Progress is reported in basic and applied agricultural research using nuclear energy as a tool. Emphasis was placed on tropical agriculture and student training. Results are reported on studies of mutations induced by irradiation of seeds or plant parts of plant species for food crops or local industrial uses. Seeds of 7 pine species that grow at altitudes of 1600 to over 3000 meters, papaya, beans, cassava branches with nodes, and young mahogany plants were irradiated and progenies were examined for mutation frequency and morphology, disease resistance, sensitivity to low temperatures, and other characteristics. Tracer studies of plant physiology includedmore » sulfur metabolism in photosynthetic bacteria and plants, iron metabolism in plants, and the effects of iron on growth of coffee and cacao seediings. Results are included from tracer studies on dispersion and longevity of the Mediterranean fruit fly under natural conditions and the effects of radiosterilization at various developmental stages on eradication of these flies. A list of publications during the period covered by this report is included. (C.H.)« less

Photoreceptor Mediated Plant Growth Responses: Implications for Photoreceptor Engineering toward Improved Performance in Crops

PubMed Central

Mawphlang, Ophilia I. L.; Kharshiing, Eros V.

2017-01-01

Rising temperatures during growing seasons coupled with altered precipitation rates presents a challenging task of improving crop productivity for overcoming such altered weather patterns and cater to a growing population. Light is a critical environmental factor that exerts a powerful influence on plant growth and development ranging from seed germination to flowering and fruiting. Higher plants utilize a suite of complex photoreceptor proteins to perceive surrounding red/far-red (phytochromes), blue/UV-A (cryptochromes, phototropins, ZTL/FKF1/LKP2), and UV-B light (UVR8). While genomic studies have also shown that light induces extensive reprogramming of gene expression patterns in plants, molecular genetic studies have shown that manipulation of one or more photoreceptors can result in modification of agronomically beneficial traits. Such information can assist researchers to engineer photoreceptors via genome editing technologies to alter expression or even sensitivity thresholds of native photoreceptors for targeting aspects of plant growth that can confer superior agronomic value to the engineered crops. Here we summarize the agronomically important plant growth processes influenced by photoreceptors in crop species, alongwith the functional interactions between different photoreceptors and phytohormones in regulating these responses. We also discuss the potential utility of synthetic biology approaches in photobiology for improving agronomically beneficial traits of crop plants by engineering designer photoreceptors. PMID:28744290

Short- and full-season soybean in stale seedbeds versus rolled-crimped winter rye mulch

USDA-ARS?s Scientific Manuscript database

Late seedbed preparations (also known as stale or false seedbeds) are used by organic growers to reduce weed populations prior to crop planting. Rye mulches, derived from mechanically killed (rolled and crimped) winter rye cover crops, can serve the same purpose for spring-planted organic crops. Bot...

Yield potential of spring-harvested sugar beet depends on autumn planting time

USDA-ARS?s Scientific Manuscript database

Sugar crops grown for biofuel production provide a source of simple sugars that can readily be made into advanced biofuels. In the mild climate of the southeastern USA, sugar beet can be grown as a winter crop, providing growers with an alternative crop. Experiments evaluated autumn planting dates...

Measuring host plant selection and retention of Halyomorpha halys by a trap crop

USDA-ARS?s Scientific Manuscript database

Trap cropping may exploit a pest’s dispersal behavior and relationship with its hosts in order to protect a desired crop. Here, we used a combination of visual sampling, immunomarking, and harmonic radar to assess host plant selection and retention time of the highly mobile and invasive Halyomorpha...

Planter closing wheel effects on cotton emergence in a conservation tillage system

USDA-ARS?s Scientific Manuscript database

Closing wheels on a row crop planter help provide good seed-soil contact during planting and can influence emergence and crop stand. Various types of closing wheels are available to producers for use on planters. Seven closing wheel types were used on a row crop planter planting cotton in a conser...

Black oat cover crop management in watermelon production systems

USDA-ARS?s Scientific Manuscript database

Black oats (Avena strigosa Schreb.) were sown as a cover crop near Weslaco, Texas (Lat. 26 deg N) in Fall 2010. The cover crop was allowed to senesce naturally and was planted to watermelons in both the spring and in the fall of 2011. Watermelon transplants planted in the spring into mowed black o...

A Method of High Throughput Monitoring Crop Physiology Using Chlorophyll Fluorescence and Multispectral Imaging.

PubMed

Wang, Heng; Qian, Xiangjie; Zhang, Lan; Xu, Sailong; Li, Haifeng; Xia, Xiaojian; Dai, Liankui; Xu, Liang; Yu, Jingquan; Liu, Xu

2018-01-01

We present a high throughput crop physiology condition monitoring system and corresponding monitoring method. The monitoring system can perform large-area chlorophyll fluorescence imaging and multispectral imaging. The monitoring method can determine the crop current condition continuously and non-destructively. We choose chlorophyll fluorescence parameters and relative reflectance of multispectral as the indicators of crop physiological status. Using tomato as experiment subject, the typical crop physiological stress, such as drought, nutrition deficiency and plant disease can be distinguished by the monitoring method. Furthermore, we have studied the correlation between the physiological indicators and the degree of stress. Besides realizing the continuous monitoring of crop physiology, the monitoring system and method provide the possibility of machine automatic diagnosis of the plant physiology. Highlights: A newly designed high throughput crop physiology monitoring system and the corresponding monitoring method are described in this study. Different types of stress can induce distinct fluorescence and spectral characteristics, which can be used to evaluate the physiological status of plants.

Improving crop nutrient efficiency through root architecture modifications.

PubMed

Li, Xinxin; Zeng, Rensen; Liao, Hong

2016-03-01

Improving crop nutrient efficiency becomes an essential consideration for environmentally friendly and sustainable agriculture. Plant growth and development is dependent on 17 essential nutrient elements, among them, nitrogen (N) and phosphorus (P) are the two most important mineral nutrients. Hence it is not surprising that low N and/or low P availability in soils severely constrains crop growth and productivity, and thereby have become high priority targets for improving nutrient efficiency in crops. Root exploration largely determines the ability of plants to acquire mineral nutrients from soils. Therefore, root architecture, the 3-dimensional configuration of the plant's root system in the soil, is of great importance for improving crop nutrient efficiency. Furthermore, the symbiotic associations between host plants and arbuscular mycorrhiza fungi/rhizobial bacteria, are additional important strategies to enhance nutrient acquisition. In this review, we summarize the recent advances in the current understanding of crop species control of root architecture alterations in response to nutrient availability and root/microbe symbioses, through gene or QTL regulation, which results in enhanced nutrient acquisition. © 2015 Institute of Botany, Chinese Academy of Sciences.

Enhancing crop yield with the use of N-based fertilizers co-applied with plant hormones or growth regulators.

PubMed

Zaman, Mohammad; Kurepin, Leonid V; Catto, Warwick; Pharis, Richard P

2015-07-01

Crop yield, vegetative or reproductive, depends on access to an adequate supply of essential mineral nutrients. At the same time, a crop plant's growth and development, and thus yield, also depend on in situ production of plant hormones. Thus optimizing mineral nutrition and providing supplemental hormones are two mechanisms for gaining appreciable yield increases. Optimizing the mineral nutrient supply is a common and accepted agricultural practice, but the co-application of nitrogen-based fertilizers with plant hormones or plant growth regulators is relatively uncommon. Our review discusses possible uses of plant hormones (gibberellins, auxins, cytokinins, abscisic acid and ethylene) and specific growth regulators (glycine betaine and polyamines) to enhance and optimize crop yield when co-applied with nitrogen-based fertilizers. We conclude that use of growth-active gibberellins, together with a nitrogen-based fertilizer, can result in appreciable and significant additive increases in shoot dry biomass of crops, including forage crops growing under low-temperature conditions. There may also be a potential for use of an auxin or cytokinin, together with a nitrogen-based fertilizer, for obtaining additive increases in dry shoot biomass and/or reproductive yield. Further research, though, is needed to determine the potential of co-application of nitrogen-based fertilizers with abscisic acid, ethylene and other growth regulators. © 2014 Society of Chemical Industry.

Introgression of physiological traits for a comprehensive improvement of drought adaptation in crop plants

NASA Astrophysics Data System (ADS)

Sreeman, Sheshshayee M.; Vijayaraghavareddy, Preethi; Sreevathsa, Rohini; Rajendrareddy, Sowmya; Arakesh, Smitharani; Bharti, Pooja; Dharmappa, Prathibha; Soolanayakanahally, Raju

2018-04-01

Burgeoning population growth, industrial demand and the predicted global climate change resulting in erratic monsoon rains are expected to severely limit fresh water availability for agriculture both in irrigated and rainfed ecosystems. In order to remain food and nutrient secure, agriculture research needs to focus on devising strategies to save water in irrigated conditions and to develop superior cultivars with improved water productivity to sustain yield under rainfed conditions. Recent opinions accruing in the scientific literature strongly favour the adoption of a “trait based” approach for increasing water productivity especially the traits associated with maintenance of positive tissue turgor and maintenance of increased carbon assimilation as the most relevant traits to improve crop growth rates under water limiting conditions and to enhance water productivity. The advent of several water saving agronomic practices notwithstanding, a genetic enhancement strategy of introgressing distinct physiological, morphological and cellular mechanisms on to a single elite genetic background is essential for achieving a comprehensive improvement in drought adaptation in crop plants. The significant progress made in genomics, though would provide the necessary impetus, a clear understanding of the “traits” to be introgressed is the most essential need of the hour. Water uptake by a better root architecture, water conservation by preventing unproductive transpiration is crucial for maintaining positive tissue water relations. Improved carbon assimilation associated with carboxylation capacity and mesophyll conductance is equally important in sustaining crop growth rates under water limited conditions. Besides these major traits, we summarized the available information in literature on classifying various drought adaptive traits. We provide evidences that water-use efficiency when introgressed with moderately higher transpiration, would significantly enhance growth rates and water productivity in rice through an improved photosynthetic capacity.

77 FR 3227 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... year experience, weather occurrences and projections, market demand, new farming techniques and... elements, as required: crop planted, planting date, crop's intended use, type or variety, practice...

An Intelligent Crop Planning Tool for Controlled Ecological Life Support Systems

NASA Technical Reports Server (NTRS)

Whitaker, Laura O.; Leon, Jorge

1996-01-01

This paper describes a crop planning tool developed for the Controlled Ecological Life Support Systems (CELSS) project which is in the research phases at various NASA facilities. The Crop Planning Tool was developed to assist in the understanding of the long term applications of a CELSS environment. The tool consists of a crop schedule generator as well as a crop schedule simulator. The importance of crop planning tools such as the one developed is discussed. The simulator is outlined in detail while the schedule generator is touched upon briefly. The simulator consists of data inputs, plant and human models, and various other CELSS activity models such as food consumption and waste regeneration. The program inputs such as crew data and crop states are discussed. References are included for all nominal parameters used. Activities including harvesting, planting, plant respiration, and human respiration are discussed using mathematical models. Plans provided to the simulator by the plan generator are evaluated for their 'fitness' to the CELSS environment with an objective function based upon daily reservoir levels. Sample runs of the Crop Planning Tool and future needs for the tool are detailed.

Elucidation of salt stress defense and tolerance mechanisms of crop plants using proteomics--current achievements and perspectives.

PubMed

Barkla, Bronwyn J; Castellanos-Cervantes, Thelma; de León, José L Diaz; Matros, Andrea; Mock, Hans-Peter; Perez-Alfocea, Francisco; Salekdeh, Ghasem H; Witzel, Katja; Zörb, Christian

2013-06-01

Salinity is a major threat limiting the productivity of crop plants. A clear demand for improving the salinity tolerance of the major crop plants is imposed by the rapidly growing world population. This review summarizes the achievements of proteomic studies to elucidate the response mechanisms of selected model and crop plants to cope with salinity stress. We also aim at identifying research areas, which deserve increased attention in future proteome studies, as a prerequisite to identify novel targets for breeding strategies. Such areas include the impact of plant-microbial communities on the salinity tolerance of crops under field conditions, the importance of hormone signaling in abiotic stress tolerance, and the significance of control mechanisms underlying the observed changes in the proteome patterns. We briefly highlight the impact of novel tools for future proteome studies and argue for the use of integrated approaches. The evaluation of genetic resources by means of novel automated phenotyping facilities will have a large impact on the application of proteomics especially in combination with metabolomics or transcriptomics. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Coupling sensing to crop models for closed-loop plant production in advanced life support systems

NASA Astrophysics Data System (ADS)

Cavazzoni, James; Ling, Peter P.

1999-01-01

We present a conceptual framework for coupling sensing to crop models for closed-loop analysis of plant production for NASA's program in advanced life support. Crop status may be monitored through non-destructive observations, while models may be independently applied to crop production planning and decision support. To achieve coupling, environmental variables and observations are linked to mode inputs and outputs, and monitoring results compared with model predictions of plant growth and development. The information thus provided may be useful in diagnosing problems with the plant growth system, or as a feedback to the model for evaluation of plant scheduling and potential yield. In this paper, we demonstrate this coupling using machine vision sensing of canopy height and top projected canopy area, and the CROPGRO crop growth model. Model simulations and scenarios are used for illustration. We also compare model predictions of the machine vision variables with data from soybean experiments conducted at New Jersey Agriculture Experiment Station Horticulture Greenhouse Facility, Rutgers University. Model simulations produce reasonable agreement with the available data, supporting our illustration.

Understanding plant response to nitrogen limitation for the improvement of crop nitrogen use efficiency.

PubMed

Kant, Surya; Bi, Yong-Mei; Rothstein, Steven J

2011-02-01

Development of genetic varieties with improved nitrogen use efficiency (NUE) is essential for sustainable agriculture. Generally, NUE can be divided into two parts. First, assimilation efficiency involves nitrogen (N) uptake and assimilation and second utilization efficiency involves N remobilization. Understanding the mechanisms regulating these processes is crucial for the improvement of NUE in crop plants. One important approach is to develop an understanding of the plant response to different N regimes, especially to N limitation, using various methods including transcription profiling, analysing mutants defective in their normal response to N limitation, and studying plants that show better growth under N-limiting conditions. One can then attempt to improve NUE in crop plants using the knowledge gained from these studies. There are several potential genetic and molecular approaches for the improvement of crop NUE discussed in this review. Increased knowledge of how plants respond to different N levels as well as to other environmental conditions is required to achieve this.

Push-Pull: Chemical Ecology-Based Integrated Pest Management Technology.

PubMed

Khan, Zeyaur; Midega, Charles A O; Hooper, Antony; Pickett, John

2016-07-01

Lepidopterous stemborers, and parasitic striga weeds belonging to the family Orobanchaceae, attack cereal crops in sub-Saharan Africa causing severe yield losses. The smallholder farmers are resource constrained and unable to afford expensive chemicals for crop protection. The push-pull technology, a chemical ecology- based cropping system, is developed for integrated pest and weed management in cereal-livestock farming systems. Appropriate plants were selected that naturally emit signaling chemicals (semiochemicals). Plants highly attractive for stemborer egg laying were selected and employed as trap crops (pull), to draw pests away from the main crop. Plants that repelled stemborer females were selected as intercrops (push). The stemborers are attracted to the trap plant, and are repelled from the main cereal crop using a repellent intercrop (push). Root exudates of leguminous repellent intercrops also effectively control the parasitic striga weed through an allelopathic mechanism. Their root exudates contain flavonoid compounds some of which stimulate germination of Striga hermonthica seeds, such as Uncinanone B, and others that dramatically inhibit their attachment to host roots, such as Uncinanone C and a number of di-C-glycosylflavones (di-CGFs), resulting in suicidal germination. The intercrop also improves soil fertility through nitrogen fixation, natural mulching, improved biomass, and control of erosion. Both companion plants provide high value animal fodder, facilitating milk production and diversifying farmers' income sources. The technology is appropriate to smallholder mixed cropping systems in Africa. Adopted by about 125,000 farmers to date in eastern Africa, it effectively addresses major production constraints, significantly increases maize yields, and is economical as it is based on locally available plants, not expensive external inputs.

Optimizing Crops for Biocontrol of Pests and Disease.

PubMed

Stenberg, Johan A; Heil, Martin; Åhman, Inger; Björkman, Christer

2015-11-01

Volatile compounds and extrafloral nectar are common defenses of wild plants; however, in crops they bear an as-yet underused potential for biological control of pests and diseases. Odor emission and nectar secretion are multigene traits in wild plants, and thus form difficult targets for breeding. Furthermore, domestication has changed the capacity of crops to express these traits. We propose that breeding crops for an enhanced capacity for tritrophic interactions and volatile-mediated direct resistance to herbivores and pathogens can contribute to environmentally-friendly and sustainable agriculture. Natural plant volatiles with antifungal or repellent properties can serve as direct resistance agents. In addition, volatiles mediating tritrophic interactions can be combined with nectar-based food rewards for carnivores to boost indirect plant defense. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Introduction to Grassland Management. Instructor Guide, Student Reference [and] Crop and Grassland Plant Identification Manual.

ERIC Educational Resources Information Center

Suits, Susie

This packet contains an Instructor guide and student reference for a course in introduction to grassland management, as well as a crop and grassland plant identification manual. The three-unit curriculum contains the following 11 lessons: (unit I, grasslands and grassland plants): (1) an introduction to grasslands; (2) plant classification; (3)…

HKT transporters mediate salt stress resistance in plants: from structure and function to the field

DOE PAGES

Hamamoto, Shin; Horie, Tomoaki; Hauser, Felix; ...

2014-12-18

Plant cells are sensitive to salinity stress and do not require sodium as an essential element for their growth and development. Saline soils reduce crop yields and limit available land. The research shows that HKT transporters provide a potent mechanism for mediating salt tolerance in plants. Knowledge of the molecular ion transport and regulation mechanisms and the control of HKT gene expression are crucial for understanding the mechanisms by which HKT transporters enhance crop performance under salinity stress. Our review focuses on HKT transporters in monocot plants and in Arabidopsis as a dicot plant, as a guide to efforts towardmore » improving salt tolerance of plants for increasing the production of crops and bioenergy feedstocks.« less

Modeling ecohydrological dynamics of smallholder strategies for food production in dryland agricultural systems

NASA Astrophysics Data System (ADS)

Gower, Drew B.; Dell'Angelo, Jampel; McCord, Paul F.; Caylor, Kelly K.; Evans, Tom P.

2016-11-01

In dryland environments, characterized by low and frequently variable rainfall, smallholder farmers must take crop water sensitivity into account along with other characteristics like seed availability and market price when deciding what to plant. In this paper we use the results of surveys conducted among smallholders located near Mount Kenya to identify clusters of farmers devoting different fractions of their land to subsistence and market crops. Additionally, we explore the tradeoffs between water-insensitive but low-value subsistence crops and a water-sensitive but high-value market crop using a numerical model that simulates soil moisture dynamics and crop production over multiple growing seasons. The cluster analysis shows that most farmers prefer to plant either only subsistence crops or only market crops, with a minority choosing to plant substantial fractions of both. The model output suggests that the value a farmer places on a successful growing season, a measure of risk aversion, plays a large role in whether the farmer chooses a subsistence or market crop strategy. Furthermore, access to irrigation, makes market crops more appealing, even to very risk-averse farmers. We then conclude that the observed clustering may result from different levels of risk aversion and access to irrigation.

78 FR 17627 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-22

... variables such as previous year experience, weather occurrences and projections, market demand, new farming..., as required: crop planted, planting date, crop's intended use, type or variety, practice (irrigated...

Kazusa Marker DataBase: a database for genomics, genetics, and molecular breeding in plants.

PubMed

Shirasawa, Kenta; Isobe, Sachiko; Tabata, Satoshi; Hirakawa, Hideki

2014-09-01

In order to provide useful genomic information for agronomical plants, we have established a database, the Kazusa Marker DataBase (http://marker.kazusa.or.jp). This database includes information on DNA markers, e.g., SSR and SNP markers, genetic linkage maps, and physical maps, that were developed at the Kazusa DNA Research Institute. Keyword searches for the markers, sequence data used for marker development, and experimental conditions are also available through this database. Currently, 10 plant species have been targeted: tomato (Solanum lycopersicum), pepper (Capsicum annuum), strawberry (Fragaria × ananassa), radish (Raphanus sativus), Lotus japonicus, soybean (Glycine max), peanut (Arachis hypogaea), red clover (Trifolium pratense), white clover (Trifolium repens), and eucalyptus (Eucalyptus camaldulensis). In addition, the number of plant species registered in this database will be increased as our research progresses. The Kazusa Marker DataBase will be a useful tool for both basic and applied sciences, such as genomics, genetics, and molecular breeding in crops.

Genetic diversity of root system architecture in response to drought stress in grain legumes.

PubMed

Ye, Heng; Roorkiwal, Manish; Valliyodan, Babu; Zhou, Lijuan; Chen, Pengyin; Varshney, Rajeev K; Nguyen, Henry T

2018-06-06

Climate change has increased the occurrence of extreme weather patterns globally, causing significant reductions in crop production, and hence threatening food security. In order to meet the food demand of the growing world population, a faster rate of genetic gains leading to productivity enhancement for major crops is required. Grain legumes are an essential commodity in optimal human diets and animal feed because of their unique nutritional composition. Currently, limited water is a major constraint in grain legume production. Root system architecture (RSA) is an important developmental and agronomic trait, which plays vital roles in plant adaptation and productivity under water-limited environments. A deep and proliferative root system helps extract sufficient water and nutrients under these stress conditions. The integrated genetics and genomics approach to dissect molecular processes from genome to phenome is key to achieve increased water capture and use efficiency through developing better root systems. Success in crop improvement under drought depends on discovery and utilization of genetic variations existing in the germplasm. In this review, we summarize current progress in the genetic diversity in major legume crops, quantitative trait loci (QTLs) associated with RSA, and the importance and applications of recent discoveries associated with the beneficial root traits towards better RSA for enhanced drought tolerance and yield.

Assessing the Crop-Water Status in Almond (Prunus dulcis Mill.) Trees via Thermal Imaging Camera Connected to Smartphone.

PubMed

García-Tejero, Iván Francisco; Ortega-Arévalo, Carlos José; Iglesias-Contreras, Manuel; Moreno, José Manuel; Souza, Luciene; Tavira, Simón Cuadros; Durán-Zuazo, Víctor Hugo

2018-03-31

Different tools are being implemented in order to improve the water management in agricultural irrigated areas of semiarid environments. Thermography has been progressively introduced as a promising technique for irrigation scheduling and the assessing of crop-water status, especially when deficit irrigation is being implemented. However, an important limitation is related to the cost of the actual cameras, this being a severe limitation to its practical usage by farmers and technicians. This work evaluates the potential and the robustness of a thermal imaging camera that is connected to smartphone (Flir One) recently developed by Flir Systems Inc. as a first step to assess the crop water status. The trial was developed in mature almond ( Prunus dulcis Mill.) trees that are subjected to different irrigation treatments. Thermal information obtained by the Flir One camera was deal with the thermal information obtained with a conventional Thermal Camera (Flir SC660) with a high resolution, and subsequently, confronted with other related plant physiological parameters (leaf water potential, Ψ leaf , and stomatal conductance, g s ). Thermal imaging camera connected to smartphone provided useful information in estimating the crop-water status in almond trees, being a potential promising tool to accelerate the monitoring process and thereby enhance water-stress management of almond orchards.

Assessing the Crop-Water Status in Almond (Prunus dulcis Mill.) Trees via Thermal Imaging Camera Connected to Smartphone

PubMed Central

García-Tejero, Iván Francisco; Ortega-Arévalo, Carlos José; Iglesias-Contreras, Manuel; Moreno, José Manuel; Souza, Luciene; Tavira, Simón Cuadros; Durán-Zuazo, Víctor Hugo

2018-01-01

Different tools are being implemented in order to improve the water management in agricultural irrigated areas of semiarid environments. Thermography has been progressively introduced as a promising technique for irrigation scheduling and the assessing of crop-water status, especially when deficit irrigation is being implemented. However, an important limitation is related to the cost of the actual cameras, this being a severe limitation to its practical usage by farmers and technicians. This work evaluates the potential and the robustness of a thermal imaging camera that is connected to smartphone (Flir One) recently developed by Flir Systems Inc. as a first step to assess the crop water status. The trial was developed in mature almond (Prunus dulcis Mill.) trees that are subjected to different irrigation treatments. Thermal information obtained by the Flir One camera was deal with the thermal information obtained with a conventional Thermal Camera (Flir SC660) with a high resolution, and subsequently, confronted with other related plant physiological parameters (leaf water potential, Ψleaf, and stomatal conductance, gs). Thermal imaging camera connected to smartphone provided useful information in estimating the crop-water status in almond trees, being a potential promising tool to accelerate the monitoring process and thereby enhance water-stress management of almond orchards. PMID:29614740

Phosphorus from wastewater to crops: An alternative path involving microalgae.

PubMed

Solovchenko, Alexei; Verschoor, Antonie M; Jablonowski, Nicolai D; Nedbal, Ladislav

2016-01-01

Phosphorus (P) is a non-renewable resource, a major plant nutrient that is essential for modern agriculture. Currently, global food and feed production depends on P extracted from finite phosphate rock reserves mainly confined to a small number of countries. P limitation and its potential socio-economic impact may well exceed the potential effects of fossil fuel scarcity. The efficiency of P usage today barely reaches 20%, with the remaining 80% ending up in wastewater or in surface waters as runoff from fields. When recovered from wastewater, either chemically or biologically, P is often present in a form that does not meet specifications for agricultural use. As an alternative, the potential of microalgae to accumulate large quantities of P can be a way to direct this resource back to crop plants. Algae can acquire and store P through luxury uptake, and the P enriched algal biomass can be used as bio-fertilizer. Technology of large-scale algae cultivation has made tremendous progress in the last decades, stimulated by perspectives of obtaining third generation biofuels without requiring arable land or fresh water. These new cultivation technologies can be used for solar-driven recycling of P and other nutrients from wastewater into algae-based bio-fertilizers. In this paper, we review the specifics of P uptake from nutrient-rich waste streams, paying special attention to luxury uptake by microalgal cells and the potential application of P-enriched algal biomass to fertilize crop soils. Copyright © 2015 Elsevier Inc. All rights reserved.

Crop resources. [18 papers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seigler, D.S.

Eighteen papers originally presented as a symposium on Crop Resources at the 17th annual meeting of the Society for Economic Botany in Urbana, Illinois, June 13 to 17, 1976 comprise this book. The papers are: Potential Wealth in New Crops: Research and Development, L. H. Princen; Plant Introductions--A Source of New Crops, George A. White; Nonfood Uses for Commercial Vegetable Oil Crops, E. H. Pryde; New Industrial Potentials for Carbohydrates, F. H. Otey; The Current Importance of Plants as a Source of Drugs, Norman R. Farnsworth; Potentials for Development of Wild Plants as Row Crops for Use by Man, Arnoldmore » Krochmal and Connie Krochmal; Recent Evidence in Support of the Tropical Origin of New World Crops, C. Earle Smith, Jr.; Requirements for a Green Revolution, G. F. Sprague; How Green Can a Revolution Be, Jack R. Harlan; Increasing Cereal Yields: Evolution under Domestication, J. M. J. de Wet; Hevea Rubber: Past and Future, Ernest P. Imle; Horseradish--Problems and Research in Illinois, A. M. Rhodes; Dioscorea--The Pill Crop, Norman Applezweig; Plant Derivatives for Insect Control, Robert L. Metcalf; Evolutionary Dynamics of Sorghum Domestication, J. M. J. de Wet and Y. Shecter; The Origin and Future of Wheat, E. R. Sears; Current Thoughts on Origins, Present Status, and Future of Soybeans, T. Hymowitz and C. A. Newell; and The Origin of Corn--Studies of the Last Hundred Years, Garrison Wilkes. (MCW)« less

Crop and medicinal plants proteomics in response to salt stress

PubMed Central

Aghaei, Keyvan; Komatsu, Setsuko

2013-01-01

Increasing of world population marks a serious need to create new crop cultivars and medicinal plants with high growth and production at any environmental situations. Among the environmental unfavorable conditions, salinity is the most widespread in the world. Crop production and growth severely decreases under salt stress; however, some crop cultivars show significant tolerance against the negative effects of salinity. Among salt stress responses of crops, proteomic responses play a pivotal role in their ability to cope with it and have become the main center of notification. Many physiological responses are detectable in terms of protein increase and decrease even before physiological responses take place. Thus proteomic approach makes a short cut in the way of inferring how crops response to salt stress. Nowadays many salt-responsive proteins such as heat shock proteins, pathogen-related proteins, protein kinases, ascorbate peroxidase, osmotin, ornithine decarboxylase, and some transcription factors, have been detected in some major crops which are thought to give them the ability of withstanding against salt stress. Proteomic analysis of medicinal plants also revealed that alkaloid biosynthesis related proteins such as tryptophan synthase, codeinone reductase, strictosidine synthase, and 12-oxophytodienoate reductase might have major role in production of secondary metabolites. In this review we are comparing some different or similar proteomic responses of several crops and medicinal plants to salt stress and discuss about the future prospects. PMID:23386857

Evaluating and optimizing horticultural regimes in space plant growth facilities

NASA Astrophysics Data System (ADS)

Berkovich, Y.; Chetirkin, R.; Wheeler, R.; Sager, J.

In designing innovative Space Plant Growth Facilities (SPGF) for long duration space f ightl various limitations must be addressed including onboard resources: volume, energy consumption, heat transfer and crew labor expenditure. The required accuracy in evaluating onboard resources by using the equivalent mass methodology and applying it to the design of such facilities is not precise. This is due to the uncertainty of the structure and not completely understanding of the properties of all associated hardware, including the technology in these systems. We present a simple criteria of optimization for horticultural regimes in SPGF: Qmax = max [M · (EBI) 2 / (V · E · T) ], where M is the crop harvest in terms of total dry biomass in the plant growth system; EBI is the edible biomass index (harvest index), V is a volume occupied by the crop; E is the crop light energy supply during growth; T is the crop growth duration. The criterion reflects directly on the consumption of onboard resources for crop production. We analyzed the efficiency of plant crops and the environmental parameters by examining the criteria for 15 salad and 12 wheat crops from the data in the ALS database at Kennedy Space Center. Some following conclusion have been established: 1. The technology involved in growing salad crops on a cylindrical type surface provides a more meaningful Q-criterion; 2. Wheat crops were less efficient than leafy greens (salad crops) when examining resource utilization; 3. By increasing light intensity of the crop the efficiency of the resource utilization could decrease. Using the existing databases and Q-criteria we have found that the criteria can be used in optimizing design and horticultural regimes in the SPGF.

Impact of climate change on crop yield and role of model for achieving food security.

PubMed

Kumar, Manoj

2016-08-01

In recent times, several studies around the globe indicate that climatic changes are likely to impact the food production and poses serious challenge to food security. In the face of climate change, agricultural systems need to adapt measures for not only increasing food supply catering to the growing population worldwide with changing dietary patterns but also to negate the negative environmental impacts on the earth. Crop simulation models are the primary tools available to assess the potential consequences of climate change on crop production and informative adaptive strategies in agriculture risk management. In consideration with the important issue, this is an attempt to provide a review on the relationship between climate change impacts and crop production. It also emphasizes the role of crop simulation models in achieving food security. Significant progress has been made in understanding the potential consequences of environment-related temperature and precipitation effect on agricultural production during the last half century. Increased CO2 fertilization has enhanced the potential impacts of climate change, but its feasibility is still in doubt and debates among researchers. To assess the potential consequences of climate change on agriculture, different crop simulation models have been developed, to provide informative strategies to avoid risks and understand the physical and biological processes. Furthermore, they can help in crop improvement programmes by identifying appropriate future crop management practises and recognizing the traits having the greatest impact on yield. Nonetheless, climate change assessment through model is subjected to a range of uncertainties. The prediction uncertainty can be reduced by using multimodel, incorporating crop modelling with plant physiology, biochemistry and gene-based modelling. For devloping new model, there is a need to generate and compile high-quality field data for model testing. Therefore, assessment of agricultural productivity to sustain food security for generations is essential to maintain a collective knowledge and resources for preventing negative impact as well as managing crop practises.

Pigeonpea genomics initiative (PGI): an international effort to improve crop productivity of pigeonpea (Cajanus cajan L.)

PubMed Central

Penmetsa, R. V.; Dutta, S.; Kulwal, P. L.; Saxena, R. K.; Datta, S.; Sharma, T. R.; Rosen, B.; Carrasquilla-Garcia, N.; Farmer, A. D.; Dubey, A.; Saxena, K. B.; Gao, J.; Fakrudin, B.; Singh, M. N.; Singh, B. P.; Wanjari, K. B.; Yuan, M.; Srivastava, R. K.; Kilian, A.; Upadhyaya, H. D.; Mallikarjuna, N.; Town, C. D.; Bruening, G. E.; He, G.; May, G. D.; McCombie, R.; Jackson, S. A.; Singh, N. K.; Cook, D. R.

2009-01-01

Pigeonpea (Cajanus cajan), an important food legume crop in the semi-arid regions of the world and the second most important pulse crop in India, has an average crop productivity of 780 kg/ha. The relatively low crop yields may be attributed to non-availability of improved cultivars, poor crop husbandry and exposure to a number of biotic and abiotic stresses in pigeonpea growing regions. Narrow genetic diversity in cultivated germplasm has further hampered the effective utilization of conventional breeding as well as development and utilization of genomic tools, resulting in pigeonpea being often referred to as an ‘orphan crop legume’. To enable genomics-assisted breeding in this crop, the pigeonpea genomics initiative (PGI) was initiated in late 2006 with funding from Indian Council of Agricultural Research under the umbrella of Indo-US agricultural knowledge initiative, which was further expanded with financial support from the US National Science Foundation’s Plant Genome Research Program and the Generation Challenge Program. As a result of the PGI, the last 3 years have witnessed significant progress in development of both genetic as well as genomic resources in this crop through effective collaborations and coordination of genomics activities across several institutes and countries. For instance, 25 mapping populations segregating for a number of biotic and abiotic stresses have been developed or are under development. An 11X-genome coverage bacterial artificial chromosome (BAC) library comprising of 69,120 clones have been developed of which 50,000 clones were end sequenced to generate 87,590 BAC-end sequences (BESs). About 10,000 expressed sequence tags (ESTs) from Sanger sequencing and ca. 2 million short ESTs by 454/FLX sequencing have been generated. A variety of molecular markers have been developed from BESs, microsatellite or simple sequence repeat (SSR)-enriched libraries and mining of ESTs and genomic amplicon sequencing. Of about 21,000 SSRs identified, 6,698 SSRs are under analysis along with 670 orthologous genes using a GoldenGate SNP (single nucleotide polymorphism) genotyping platform, with large scale SNP discovery using Solexa, a next generation sequencing technology, is in progress. Similarly a diversity array technology array comprising of ca. 15,000 features has been developed. In addition, >600 unique nucleotide binding site (NBS) domain containing members of the NBS-leucine rich repeat disease resistance homologs were cloned in pigeonpea; 960 BACs containing these sequences were identified by filter hybridization, BES physical maps developed using high information content fingerprinting. To enrich the genomic resources further, sequenced soybean genome is being analyzed to establish the anchor points between pigeonpea and soybean genomes. In addition, Solexa sequencing is being used to explore the feasibility of generating whole genome sequence. In summary, the collaborative efforts of several research groups under the umbrella of PGI are making significant progress in improving molecular tools in pigeonpea and should significantly benefit pigeonpea genetics and breeding. As these efforts come to fruition, and expanded (depending on funding), pigeonpea would move from an ‘orphan legume crop’ to one where genomics-assisted breeding approaches for a sustainable crop improvement are routine. PMID:20976284

Forage radish winter cover crop suppresses winter annual weeds in fall and before corn planting

USDA-ARS?s Scientific Manuscript database

Forage radish (Raphanus sativus L. var. longipinnatus) is a new winter cover crop in the Mid-Atlantic region. The objective of this project was to characterize the repeatability, amount, and duration of weed suppression during and after a fall-planted forage radish cover crop and to quantify the sub...

7 CFR 457.104 - Cotton crop insurance provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

...; (2) Planted into an established grass or legume; (3) Interplanted with another spring planted crop...) Wildlife; (f) Earthquake; (g) Volcanic eruption; or (h) Failure of the irrigation water supply, if...

Comparative genomics of grass EST libraries reveals previously uncharacterized splicing events in crop plants.

PubMed

Chuang, Trees-Juen; Yang, Min-Yu; Lin, Chuang-Chieh; Hsieh, Ping-Hung; Hung, Li-Yuan

2015-02-05

Crop plants such as rice, maize and sorghum play economically-important roles as main sources of food, fuel, and animal feed. However, current genome annotations of crop plants still suffer false-positive predictions; a more comprehensive registry of alternative splicing (AS) events is also in demand. Comparative genomics of crop plants is largely unexplored. We performed a large-scale comparative analysis (ExonFinder) of the expressed sequence tag (EST) library from nine grass plants against three crop genomes (rice, maize, and sorghum) and identified 2,879 previously-unannotated exons (i.e., novel exons) in the three crops. We validated 81% of the tested exons by RT-PCR-sequencing, supporting the effectiveness of our in silico strategy. Evolutionary analysis reveals that the novel exons, comparing with their flanking annotated ones, are generally under weaker selection pressure at the protein level, but under stronger pressure at the RNA level, suggesting that most of the novel exons also represent novel alternatively spliced variants (ASVs). However, we also observed the consistency of evolutionary rates between certain novel exons and their flanking exons, which provided further evidence of their co-occurrence in the transcripts, suggesting that previously-annotated isoforms might be subject to erroneous predictions. Our validation showed that 54% of the tested genes expressed the newly-identified isoforms that contained the novel exons, rather than the previously-annotated isoforms that excluded them. The consistent results were steadily observed across cultivated (Oryza sativa and O. glaberrima) and wild (O. rufipogon and O. nivara) rice species, asserting the necessity of our curation of the crop genome annotations. Our comparative analyses also inferred the common ancestral transcriptome of grass plants and gain- and loss-of-ASV events. We have reannotated the rice, maize, and sorghum genomes, and showed that evolutionary rates might serve as an indicator for determining whether the identified exons were alternatively spliced. This study not only presents an effective in silico strategy for the improvement of plant annotations, but also provides further insights into the role of AS events in the evolution and domestication of crop plants. ExonFinder and the novel exons/ASVs identified are publicly accessible at http://exonfinder.sourceforge.net/ .

Ground-based hyperspectral remote sensing to discriminate biotic stress in cotton crop

NASA Astrophysics Data System (ADS)

Nigam, Rahul; Kot, Rajsi; Sandhu, Sandeep S.; Bhattacharya, Bimal K.; Chandi, Ravinder S.; Singh, Manjeet; Singh, Jagdish; Manjunath, K. R.

2016-05-01

A large gap exists between the potential yield and the yield realized at the agricultural field. Among the factors contributing towards this yield gap are the biotic stresses that affect the crops growth and development. Severity of infestation of the pests and diseases differs between agroclimatic region, individual crops and seasons within a region. Information about the timing of start of infestation of these diseases and pests with their gradual progress in advance could enable plan necessary pesticide schedule for the season, region on the particular crop against the specific menace expected. This could be enabled by development of region, crop and pest-specific prediction models to forewarn these menaces. In India most (70%) of the land-holding size of farmers average 0.39 ha (some even 20 m x 20 m) and only 1% crop growers hold< 10 ha (mean: 17.3 ha). Patchiness of disease and pest incidence could pose problems in its proper assessment and management. Thus, such exercise could be highly time-consuming and labour-intensive for the seventh largest country with difficult terrain, 66% gross cropped area under food crops, lacking in number of skilled manpower and shrinking resources. Remote sensing overcomes such limitations with ability to access all parts of the country and can often achieve a high spatial, temporal and spectral resolution and thus leading to an accurate estimation of area affected. Due to pest and disease stress plants showed different behavior in terms of physiological and morphological changes lead to symptoms such as wilting, curling of leaf, stunned growth, reduction in leaf area due to severe defoliation or chlorosis or necrosis of photosynthetically active parts (Prabhakar et al., 2011; Booteet al., 1983; Aggarwal et al., 2006). Damage evaluation of diseases has been largely done by visual inspections and quantification but visual quantification of plant pest and diseases with accuracy and precision is a tough task. Utilization of remote sensing techniques are based on the assumption that plant pest and disease stresses interfere with physical structure and function of plant and influence the absorption of light energy and therefore changes the reflectance spectrum of plants. Moreover, remote sensing provides better means to objectively quantify crop stress than visual methods and it can be used repeatedly to collect sample measurements non-destructively and non-invasively (Nutteret et al., 1990; Nilson, 1995). Recent advances in the field of spectroscopy and other remote sensing techniques offer much needed technology of hyperspectral remote sensing (Prabhakar et al., 2011). Hyperspectral remote sensing for disease detection helps in monitoring the diseases in plants with the help of different plant spectral properties at the visible, near infrared and shortwave infrared regions ranging from 350 - 2500 nm, which develops specific signatures for a specific stress for a given plant (Yang et al., 2009). It has been effectively used in assessment of disease in agricultural crops like wheat, rice, tomato etc across the world. Cotton (Gissypium hirsutum L.) is one of the major commercial crops grown in India, and supports about 60 million people in the country directly or indirectly through the process of production, processing, marketing and trade (Prabhakar et al., 2011). India ranks first in global acreage, occupying about 33% of world cotton area. With regard to production it is ranked second next to China. In recent years, farmers are facing many challenges because of rising incidents of white flies, jassid, leafhoppers, aphids, mealybugs and stainers. Whiteflies are tiny, sap- sucking insects that may become abundant in vegetable and ornamental plantings, especially during warm weather. They excrete sticky honeydew and cause yellowing or death of leaves. Outbreaks often occur when the natural biological control is disrupted. Management is difficult once populations are high. White flies develop rapidly in warm weather, and populations can build up quickly in situations where natural enemies are ineffective and when weather and host plants favor outbreaks. Large colonies often develop on the undersides of leaves. The most common pest species such as greenhouse white fly (Trialeurodes vaporariorum) and sweet potato white fly (Bemisia tabaci) have a wide host range that includes many weeds and crops. White flies normally lay their tiny oblong eggs on the undersides of leaves. The eggs hatch, and the young white flies gradually increase in size through four nymphal stages called instars. The first nymphal stage (crawler) is barely visible even with a hand lens. The crawlers move around for several hours before settling to begin feeding. Later nymphal stages are immobile, oval, and flattened, with greatly reduced legs and antennae, like small scale insects. The winged adult emerges from the last nymphal stage (sometimes called a pupa, although whiteflies don't have a true complete metamorphosis). All stages feed by sucking plant juices from leaves and excreting excess liquid as drops of honeydew as they feed. White flies use their piercing, needle like mouthparts to suck sap from phloem, the food-conducting tissues in plant stems and leaves. Large populations can cause leaves to turn yellow, appear dry, or fall off plants. Like aphids, white flies excrete sugary liquid called honeydew, so leaves may be sticky or covered with black sooty mold that grows on honeydew. The honeydew attracts ants, which interfere with the activities of natural enemies that may control white flies and other pests. High white fly infestation was reported at several locations in Punjab during year 2015. The application of non-destructive methods to detect vegetation stress at an early stage of its development is very important for pest management in commercially important crops. Earlier few studies have been done to characterize reflectance spectra of nutrient stress nitrogen deficiency and irrigation management for cotton but no literature is available regarding characterization of spectral reflectance to study white fly infestation. Therefore, the primary objectives of this study are: (i) to study changes in chlorophyll content and water content due to white fly infestation. (ii) characterization of spectral signature from cotton crop infested by white fly, (iii) establishment of most sensitive wavebands to white fly infestation.

Plants under stress by parasitic plants.

PubMed

Hegenauer, Volker; Körner, Max; Albert, Markus

2017-08-01

In addition to other biotic stresses, parasitic plants pose an additional threat to plants and cause crop losses, worldwide. Plant parasites directly connect to the vasculature of host plants thereby stealing water, nutrients, and carbohydrates consequently leading to tremendously reduced biomass and losses in seed yields of the infected host plants. Initial steps to understand the molecular resistance mechanisms and the successes in ancient and recent breeding efforts will provide fundamental knowledge to further generate crop plants that will resist attacks by plant parasites. Copyright © 2017 Elsevier Ltd. All rights reserved.

The impact of cotton growing practices on soil microbiology and its relation to plant and soil health

NASA Astrophysics Data System (ADS)

Pereg, Lily

2013-04-01

Crop production and agricultural practices heavily impact the soil microbial communities, which differ among varying types of soils and environmental conditions. Soil-borne microbial communities in cotton production systems, as in every other cropping system, consist of microbial populations that may either be pathogenic, beneficial or neutral with respect to the cotton crop. Crop production practices have major roles in determining the composition of microbial communities and function of microbial populations in soils. The structure and function of any given microbial community is determined by various factors, including those that are influenced by farming and those not controlled by farming activities. Examples of the latter are environmental conditions such as soil type, temperature, daylight length and UV radiation, air humidity, atmospheric pressure and some abiotic features of the soil. On the other hand, crop production practices may determine other abiotic soil properties, such as water content, density, oxygen levels, mineral and elemental nutrient levels and the load of other crop-related soil amendments. Moreover, crop production highly influences the biotic properties of the soil and has a major role in determining the fate of soil-borne microbial communities associated with the crop plant. Various microbial strains react differently to the presence of certain plants and plant exudates. Therefore, the type of plant and crop rotations are important factors determining microbial communities. In addition, practice management, e.g. soil cultivation versus crop stubble retention, have a major effect on the soil conditions and, thus, on microbial community structure and function. All of the above-mentioned factors can lead to preferential selection of certain microbial population over others. It may affect not only the composition of microbial communities (diversity and abundance of microbial members) but also the function of the community (the ability of different microbes to perform certain activities). Therefore, agricultural practices may determine the ability of beneficial microbes to realise their plant growth promoting potential or the pathogenic expression of others. This presentation will review the current knowledge about the impact of cotton growing practices on microbial communities and soil health in different environments as well as endeavour to identify gaps worthwhile exploring in future research for promoting plant growth in healthy soils.

Improving containment strategies in biopharming.

PubMed

Murphy, Denis J

2007-09-01

This review examines the challenges of segregating biopharmed crops expressing pharmaceutical or veterinary agents from mainstream crops, particularly those destined for food or feed use. The strategy of using major food crops as production vehicles for the expression of pharmaceutical or veterinary agents is critically analysed in the light of several recent episodes of contamination of the human food chain by non-approved crop varieties. Commercially viable strategies to limit or avoid biopharming intrusion into the human food chain require the more rigorous segregation of food and non-food varieties of the same crop species via a range of either physical or biological methods. Even more secure segregation is possible by the use of non-food crops, non-crop plants or in vitro plant cultures as production platforms for biopharming. Such platforms already under development range from outdoor-grown Nicotiana spp. to glasshouse-grown Arabidopsis, lotus and moss. Amongst the more effective methods for biocontainment are the plastid expression of transgenes, inducible and transient expression systems, and physical containment of plants or cell cultures. In the current atmosphere of heightened concerns over food safety and biosecurity, the future of biopharming may be largely determined by the extent to which the sector is able to maintain public confidence via a more considered approach to containment and security of its plant production systems.

78 FR 70485 - Common Crop Insurance Regulations; Extra Long Staple Cotton Crop Provisions

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-26

...-0002] RIN 0563-AC41 Common Crop Insurance Regulations; Extra Long Staple Cotton Crop Provisions AGENCY... Cotton Crop Insurance Provisions to make the Extra Long Staple (ELS) Cotton Crop Insurance Provisions consistent with the Upland Cotton Crop Insurance Provisions and to allow a late planting period. The intended...

Lights, camera, action: high-throughput plant phenotyping is ready for a close-up

USDA-ARS?s Scientific Manuscript database

Modern techniques for crop improvement rely on both DNA sequencing and accurate quantification of plant traits to identify genes and germplasm of interest. With rapid advances in DNA sequencing technologies, plant phenotyping is now a bottleneck in advancing crop yields [1,2]. Furthermore, the envir...

The National Plant Germplasm System: the subtropical and tropical fruit genebanks

USDA-ARS?s Scientific Manuscript database

The National Plant Germplasm System (NPGS) is a network of 29 repositories nationwide that preserve, characterize and regenerate seed and other tissues of crop plants and their wild relatives. The system houses more than 500,000 accessions comprising over 2100 genera and more than 13,100 crop specie...

7 CFR 407.15 - Group risk plan for sorghum.

Code of Federal Regulations, 2012 CFR

2012-01-01

... expected county yield and calculate indemnities. Planted acreage. Land in which the sorghum seed has been... subsequent mechanical incorporation of the sorghum seed is not allowed. 2. Crop Insured (a) The insured crop... application; (2) Properly planted and reported by the acreage reporting date; (3) Planted with the intent to...

7 CFR 407.15 - Area risk protection insurance for grain sorghum.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Insurance Basic Provisions, sorghum seed broadcast and subsequently mechanically incorporated will not be considered planted. 2. Insured Crop (a) The insured crop will be all sorghum excluding hybrid sorghum seed... by the final planting date and reported on or before the acreage reporting date; (3) Planted with the...

7 CFR 407.15 - Group risk plan for sorghum.

Code of Federal Regulations, 2011 CFR

2011-01-01

... expected county yield and calculate indemnities. Planted acreage. Land in which the sorghum seed has been... subsequent mechanical incorporation of the sorghum seed is not allowed. 2. Crop Insured (a) The insured crop... application; (2) Properly planted and reported by the acreage reporting date; (3) Planted with the intent to...

Zinc deficiency alters soybean susceptibility to pathogens and pests

USDA-ARS?s Scientific Manuscript database

Inadequate plant nutrition and biotic stress are key threats to current and future crop yields. Zinc deficiency and toxicity in major crop plants have been documented, but there is limited information on how pathogen and pest damage may be affected by differing plant zinc levels. In our study, we us...

Estimating plant available water for general crop simulations in ALMANAC/APEX/EPIC/SWAT

USDA-ARS?s Scientific Manuscript database

Process-based simulation models ALMANAC/APEX/EPIC/SWAT contain generalized plant growth subroutines to predict biomass and crop yield. Environmental constraints typically restrict plant growth and yield. Water stress is often an important limiting factor; it is calculated as the sum of water use f...

Estimating the impact of mineral aerosols on crop yields in food insecure regions using statistical crop models

NASA Astrophysics Data System (ADS)

Hoffman, A.; Forest, C. E.; Kemanian, A.

2016-12-01

A significant number of food-insecure nations exist in regions of the world where dust plays a large role in the climate system. While the impacts of common climate variables (e.g. temperature, precipitation, ozone, and carbon dioxide) on crop yields are relatively well understood, the impact of mineral aerosols on yields have not yet been thoroughly investigated. This research aims to develop the data and tools to progress our understanding of mineral aerosol impacts on crop yields. Suspended dust affects crop yields by altering the amount and type of radiation reaching the plant, modifying local temperature and precipitation. While dust events (i.e. dust storms) affect crop yields by depleting the soil of nutrients or by defoliation via particle abrasion. The impact of dust on yields is modeled statistically because we are uncertain which impacts will dominate the response on national and regional scales considered in this study. Multiple linear regression is used in a number of large-scale statistical crop modeling studies to estimate yield responses to various climate variables. In alignment with previous work, we develop linear crop models, but build upon this simple method of regression with machine-learning techniques (e.g. random forests) to identify important statistical predictors and isolate how dust affects yields on the scales of interest. To perform this analysis, we develop a crop-climate dataset for maize, soybean, groundnut, sorghum, rice, and wheat for the regions of West Africa, East Africa, South Africa, and the Sahel. Random forest regression models consistently model historic crop yields better than the linear models. In several instances, the random forest models accurately capture the temperature and precipitation threshold behavior in crops. Additionally, improving agricultural technology has caused a well-documented positive trend that dominates time series of global and regional yields. This trend is often removed before regression with traditional crop models, but likely at the cost of removing climate information. Our random forest models consistently discover the positive trend without removing any additional data. The application of random forests as a statistical crop model provides insight into understanding the impact of dust on yields in marginal food producing regions.

The role of plant-microbiome interactions in weed establishment and control.

PubMed

Trognitz, Friederike; Hackl, Evelyn; Widhalm, Siegrid; Sessitsch, Angela

2016-10-01

The soil microbiome plays an important role in the establishment of weeds and invasive plants. They associate with microorganisms supporting their growth and health. Weed management strategies, like tillage and herbicide treatments, to control weeds generally alter soil structure going alongside with changes in the microbial community. Once a weed population establishes in the field, the plants build up a close relationship with the available microorganisms. Seeds or vegetative organs overwinter in soil and select early in the season their own microbiome before crop plants start to vegetate. Weed and crop plants compete for light, nutrition and water, but may differently interact with soil microorganisms. The development of new sequencing technologies for analyzing soil microbiomes has opened up the possibility for in depth analysis of the interaction between 'undesired' plants and crop plants under different management systems. These findings will help us to understand the functions of microorganisms involved in crop productivity and plant health, weed establishment and weed prevention. Exploitation of the knowledge offers the possibility to search for new biocontrol methods against weeds based on soil and plant-associated microorganisms. This review discusses the recent advances in understanding the functions of microbial communities for weed/invasive plant establishment and shows new ways to use plant-associated microorganisms to control weeds and invasive plants in different land management systems. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Plant volatile-mediated signalling and its application in agriculture: successes and challenges.

PubMed

Pickett, John A; Khan, Zeyaur R

2016-12-01

856 I. 856 II. 857 III. 858 IV. 859 V. 860 VI. 862 VII. 863 VIII. 864 IX. 866 866 References 866 SUMMARY: The mediation of volatile secondary metabolites in signalling between plants and other organisms has long been seen as presenting opportunities for sustainable crop protection. Initially, exploitation of interactions between plants and other organisms, particularly insect pests, foundered because of difficulties in delivering, sustainably, the signal systems for crop protection. We now have mounting and, in some cases, clear practical evidence for successful delivery by companion cropping or next-generation genetic modification (GM). At the same time, the type of plant signalling being exploited has expanded to signalling from plants to organisms antagonistic to pests, and to plant stress-induced, or primed, plant-to-plant signalling for defence and growth stimulation. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Reflectance of vegetation, soil, and water. [effects of measurable plant parameters on multispectral signal variations

NASA Technical Reports Server (NTRS)

Wiegand, C. L. (Principal Investigator)

1974-01-01

The author has identified the following significant results. Reflectance of crop residues, that are important in reducing wind and water erosion, was more often different from bare soil in band 4 than in bands 5, 6, or 7. The plant parameters leaf area index, plant population, plant cover, and plant height explained 95.9 percent of the variation in band 7 (reflective infrared) digital counts for cotton and 78.2 percent of the variation in digital counts for the combined crops sorghum and corn; hence, measurable plant parameters explain most of the signal variation recorded for corpland. Leaf area index and plant population are both highly correlated with crop yields; since plant population can be readily measured (or possibly inferred from seeding rates), it is useful measurement for calibrating ERTS-type MSS digital data in terms of yield.

Managing Phenol Contents in Crop Plants by Phytochemical Farming and Breeding—Visions and Constraints

PubMed Central

Treutter, Dieter

2010-01-01

Two main fields of interest form the background of actual demand for optimized levels of phenolic compounds in crop plants. These are human health and plant resistance to pathogens and to biotic and abiotic stress factors. A survey of agricultural technologies influencing the biosynthesis and accumulation of phenolic compounds in crop plants is presented, including observations on the effects of light, temperature, mineral nutrition, water management, grafting, elevated atmospheric CO2, growth and differentiation of the plant and application of elicitors, stimulating agents and plant activators. The underlying mechanisms are discussed with respect to carbohydrate availability, trade-offs to competing demands as well as to regulatory elements. Outlines are given for genetic engineering and plant breeding. Constraints and possible physiological feedbacks are considered for successful and sustainable application of agricultural techniques with respect to management of plant phenol profiles and concentrations. PMID:20479987

Precision genome engineering and agriculture: opportunities and regulatory challenges.

PubMed

Voytas, Daniel F; Gao, Caixia

2014-06-01

Plant agriculture is poised at a technological inflection point. Recent advances in genome engineering make it possible to precisely alter DNA sequences in living cells, providing unprecedented control over a plant's genetic material. Potential future crops derived through genome engineering include those that better withstand pests, that have enhanced nutritional value, and that are able to grow on marginal lands. In many instances, crops with such traits will be created by altering only a few nucleotides among the billions that comprise plant genomes. As such, and with the appropriate regulatory structures in place, crops created through genome engineering might prove to be more acceptable to the public than plants that carry foreign DNA in their genomes. Public perception and the performance of the engineered crop varieties will determine the extent to which this powerful technology contributes towards securing the world's food supply.

HKT transporters mediate salt stress resistance in plants: from structure and function to the field.

PubMed

Hamamoto, Shin; Horie, Tomoaki; Hauser, Felix; Deinlein, Ulrich; Schroeder, Julian I; Uozumi, Nobuyuki

2015-04-01

Plant cells are sensitive to salinity stress and do not require sodium as an essential element for their growth and development. Saline soils reduce crop yields and limit available land. Research shows that HKT transporters provide a potent mechanism for mediating salt tolerance in plants. Knowledge of the molecular ion transport and regulation mechanisms and the control of HKT gene expression are crucial for understanding the mechanisms by which HKT transporters enhance crop performance under salinity stress. This review focuses on HKT transporters in monocot plants and in Arabidopsis as a dicot plant, as a guide to efforts toward improving salt tolerance of plants for increasing the production of crops and bioenergy feedstocks. Copyright © 2014 Elsevier Ltd. All rights reserved.

A model of plant canopy polarization

NASA Technical Reports Server (NTRS)

Vanderbilt, V. C.

1980-01-01

A model for the amount of linearly polarized light reflected by the shiny leaves of grain crops is based on the morphological and phenological characteristics of the plant canopy and upon the Fresnel equations which describe the light reflection process at the smooth boundary separating two dielectrics. The theory used demonstrates that, potentially, measurements of the linearly polarized light from a crop canopy may be used as an additional feature to discriminate between crops such as wheat and barley, two crops which are so spectrally similar that they are misclassified with unacceptable frequency. Examination of the model suggests that, potentially, satellite polarization measurements may be used to monitor crop development stage, leaf water content, leaf area index, hail damage, and certain plant diseases. The information content of these measurements is needed to evaluate the proposed polarization sensor for the satellite-borne multispectral resource sampler.

Cover crop biomass harvest for bioenergy: implications for crop productivity

USDA-ARS?s Scientific Manuscript database

Winter cover crops, such as rye (Secale cereale), are usually used in conservation agriculture systems in the Southeast. Typically, the cover crop is terminated two to three weeks before planting the summer crop, with the cover biomass left on the soil surface as a mulch. However, these cover crops ...

Enabling Philippine Farmers to Adapt to Climate Variability Using Seasonal Climate and Weather Forecast with a Crop Simulation Model in an SMS-based Farmer Decision Support System

NASA Astrophysics Data System (ADS)

Ebardaloza, J. B. R.; Trogo, R.; Sabido, D. J.; Tongson, E.; Bagtasa, G.; Balderama, O. F.

2015-12-01

Corn farms in the Philippines are rainfed farms, hence, it is of utmost importance to choose the start of planting date so that the critical growth stages that are in need of water will fall on dates when there is rain. Most farmers in the Philippines use superstitions and traditions as basis for farming decisions such as when to start planting [1]. Before climate change, superstitions like planting after a feast day of a saint has worked for them but with the recent progression of climate change, farmers now recognize that there is a need for technological intervention [1]. The application discussed in this paper presents a solution that makes use of meteorological station sensors, localized seasonal climate forecast, localized weather forecast and a crop simulation model to provide recommendations to farmers based on the crop cultivar, soil type and fertilizer type used by farmers. It is critical that the recommendations given to farmers are not generic as each farmer would have different needs based on their cultivar, soil, fertilizer, planting schedule and even location [2]. This application allows the farmer to inquire about whether it will rain in the next seven days, the best date to start planting based on the potential yield upon harvest, when to apply fertilizer and by how much, when to water and by how much. Short messaging service (SMS) is the medium chosen for this application because while mobile penetration in the Philippines is as high as 101%, the smart phone penetration is only at 15% [3]. SMS has been selected as it has been identified as the most effective way of reaching farmers with timely agricultural information and knowledge [4,5]. The recommendations while derived from making use of Automated Weather Station (AWS) sensor data, Weather Research Forecasting (WRF) models and DSSAT 4.5 [9], are translated into the local language of the farmers and in a format that is easily understood as recommended in [6,7,8]. A pilot study has been started in May 2015 and the harvest of this pilot season will be September 2015.

Sugarcane crop residue and bagasse allelopathic impact on oat (Avena sative L.), tall morningglory (Ipomoea purpurea L. Roth), and redroot pigweed (Amaranthus retroflexus L.) germination

USDA-ARS?s Scientific Manuscript database

Allelopathy, the chemical interaction between plants, may result in the inhibition of plant growth and development, and can include compounds released from a crop that adversely impact crop or weed species. The objective of this research was to determine the allelopathic impact of sugarcane (Sacchar...

Recent progress and future challenges in algal biofuel production

PubMed Central

Shurin, Jonathan B.; Burkart, Michael D.; Mayfield, Stephen P.

2016-01-01

Modern society is fueled by fossil energy produced millions of years ago by photosynthetic organisms. Cultivating contemporary photosynthetic producers to generate energy and capture carbon from the atmosphere is one potential approach to sustaining society without disrupting the climate. Algae, photosynthetic aquatic microorganisms, are the fastest growing primary producers in the world and can therefore produce more energy with less land, water, and nutrients than terrestrial plant crops. We review recent progress and challenges in developing bioenergy technology based on algae. A variety of high-value products in addition to biofuels can be harvested from algal biomass, and these may be key to developing algal biotechnology and realizing the commercial potential of these organisms. Aspects of algal biology that differentiate them from plants demand an integrative approach based on genetics, cell biology, ecology, and evolution. We call for a systems approach to research on algal biotechnology rooted in understanding their biology, from the level of genes to ecosystems, and integrating perspectives from physical, chemical, and social sciences to solve one of the most critical outstanding technological problems. PMID:27781084

Major Energy Plants and Their Potential for Bioenergy Development in China

NASA Astrophysics Data System (ADS)

Li, Xiaofeng; Hou, Shenglin; Su, Man; Yang, Mingfeng; Shen, Shihua; Jiang, Gaoming; Qi, Dongmei; Chen, Shuangyan; Liu, Gongshe

2010-10-01

China is rich in energy plant resources. In this article, 64 plant species are identified as potential energy plants in China. The energy plant species include 38 oilseed crops, 5 starch-producing crops, 3 sugar-producing crops and 18 species for lignocellulosic biomass. The species were evaluated on the basis of their production capacity and their resistance to salt, drought, and/or low temperature stress. Ten plant species have high production and/or stress resistance and can be potentially developed as the candidate energy plants. Of these, four species could be the primary energy plants in China: Barbados nut ( Jatropha curcas L.), Jerusalem artichoke ( Helianthus tuberosus L.), sweet sorghum ( Sorghum bicolor L.) and Chinese silvergrass ( Miscanthus sinensis Anderss.). We discuss the use of biotechnological techniques such as genome sequencing, molecular markers, and genetic transformation to improve energy plants. These techniques are being used to develop new cultivars and to analyze and manipulate genetic variation to improve attributes of energy plants in China.

Biosafety, risk assessment and regulation of plant-made pharmaceuticals.

PubMed

Sparrow, Penelope A C; Twyman, Richard M

2009-01-01

The technology for plant-made pharmaceuticals (PMPs) has progressed significantly over the last few years, with the first commercial products for human use expected to reach the market by 2009 (see Note 1). As part of the 'next generation' of genetically modified (GM) crops, PMPs will be subject to additional biosafety considerations and are set to challenge the complex and overlapping regulations that currently govern GM plants, plant biologics (see Note 2) and 'conventional' pharmaceutical production. The areas of responsibility are being mapped out between the different regulatory agencies (Sparrow, P.A.C., Irwin, J., Dale, P., Twyman, R.M., and Ma, J.K.C. (2007) Pharma-Planta: Road testing the developing regulatory guidelines for plant-made pharmaceuticals. Transgenic Res., 2007), with specific guidelines currently being drawn up for the regulation of PMPs. In this chapter, we provide an overview of the biosafety (see Note 3), risk assessment (see Note 4) and regulation of this emerging technology. While reference will be made to EU regulations, the underlying principles of biosafety and risk assessment are generic to most countries.

Nitrogen fertility and abiotic stresses management in cotton crop: a review.

PubMed

Khan, Aziz; Tan, Daniel Kean Yuen; Afridi, Muhammad Zahir; Luo, Honghai; Tung, Shahbaz Atta; Ajab, Mir; Fahad, Shah

2017-06-01

This review outlines nitrogen (N) responses in crop production and potential management decisions to ameliorate abiotic stresses for better crop production. N is a primary constituent of the nucleotides and proteins that are essential for life. Production and application of N fertilizers consume huge amounts of energy, and excess is detrimental to the environment. Therefore, increasing plant N use efficiency (NUE) is important for the development of sustainable agriculture. NUE has a key role in crop yield and can be enhanced by controlling loss of fertilizers by application of humic acid and natural polymers (hydrogels), having high water-holding capacity which can improve plant performance under field conditions. Abiotic stresses such as waterlogging, drought, heat, and salinity are the major limitations for successful crop production. Therefore, integrated management approaches such as addition of aminoethoxyvinylglycine (AVG), the film antitranspirant (di-1-p-menthene and pinolene) nutrients, hydrogels, and phytohormones may provide novel approaches to improve plant tolerance against abiotic stress-induced damage. Moreover, for plant breeders and molecular biologists, it is a challenge to develop cotton cultivars that can tolerate plant abiotic stresses while having high potential NUE for the future.

How healthy is urban horticulture in high traffic areas? Trace metal concentrations in vegetable crops from plantings within inner city neighbourhoods in Berlin, Germany.

PubMed

Säumel, Ina; Kotsyuk, Iryna; Hölscher, Marie; Lenkereit, Claudia; Weber, Frauke; Kowarik, Ingo

2012-06-01

Food production by urban dwellers is of growing importance in developing and developed countries. Urban horticulture is associated with health risks as crops in urban settings are generally exposed to higher levels of pollutants than those in rural areas. We determined the concentration of trace metals in the biomass of different horticultural crops grown in the inner city of Berlin, Germany, and analysed how the local setting shaped the concentration patterns. We revealed significant differences in trace metal concentrations depending on local traffic, crop species, planting style and building structures, but not on vegetable type. Higher overall traffic burden increased trace metal content in the biomass. The presence of buildings and large masses of vegetation as barriers between crops and roads reduced trace metal content in the biomass. Based on this we discuss consequences for urban horticulture, risk assessment, and planting and monitoring guidelines for cultivation and consumption of crops. Copyright © 2012 Elsevier Ltd. All rights reserved.

Endophytic fungal diversity of Fragaria vesca, a crop wild relative of strawberry, along environmental gradients within a small geographical area

PubMed Central

Yokoya, Kazutomo; Postel, Sarah; Fang, Rui

2017-01-01

Background Fungal endophytes are highly diverse ubiquitous asymptomatic microorganisms, some of which appear to be symbiotic. Depending on abiotic conditions and genotype of the plant, the diversity of endophytes may confer fitness benefits to plant communities. Methods We studied a crop wild relative (CWR) of strawberry, along environmental gradients with a view to understand the cultivable root-derived endophytic fungi that can be evaluated for promoting growth and tolerating stress in selected plant groups. The main objectives were to understand whether: (a) suboptimal soil types are drivers for fungal distribution and diversity; (b) high pH and poor nutrient availability lead to fungal-plant associations that help deliver fitness benefits; and (c) novel fungi can be identified for their use in improving plant growth, and alleviate stress in diverse crops. Results The study revealed that habitats with high pH and low nutrient availability have higher fungal diversity, with more rare fungi isolated from locations with chalky soil. Plants from location G were the healthiest even though soil from this location was the poorest in nutrients. Study of environmental gradients, especially extreme habitat types, may help understand the root zone fungal diversity of different functional classes. Two small in vitro pilot studies conducted with two isolates showed that endophytic fungi from suboptimal habitats can promote plant growth and fitness benefits in selected plant groups. Discussion Targeting native plants and crop wild relatives for research offers opportunities to unearth diverse functional groups of root-derived endophytic fungi that are beneficial for crops. PMID:28168102

Manipulating microRNAs for improved biomass and biofuels from plant feedstocks.

PubMed

Trumbo, Jennifer Lynn; Zhang, Baohong; Stewart, Charles Neal

2015-04-01

Petroleum-based fuels are nonrenewable and unsustainable. Renewable sources of energy, such as lignocellulosic biofuels and plant metabolite-based drop-in fuels, can offset fossil fuel use and reverse environmental degradation through carbon sequestration. Despite these benefits, the lignocellulosic biofuels industry still faces many challenges, including the availability of economically viable crop plants. Cell wall recalcitrance is a major economic barrier for lignocellulosic biofuels production from biomass crops. Sustainability and biomass yield are two additional, yet interrelated, foci for biomass crop improvement. Many scientists are searching for solutions to these problems within biomass crop genomes. MicroRNAs (miRNAs) are involved in almost all biological and metabolic process in plants including plant development, cell wall biosynthesis and plant stress responses. Because of the broad functions of their targets (e.g. auxin response factors), the alteration of plant miRNA expression often results in pleiotropic effects. A specific miRNA usually regulates a biologically relevant bioenergy trait. For example, relatively low miR156 overexpression leads to a transgenic feedstock with enhanced biomass and decreased recalcitrance. miRNAs have been overexpressed in dedicated bioenergy feedstocks such as poplar and switchgrass yielding promising results for lignin reduction, increased plant biomass, the timing of flowering and response to harsh environments. In this review, we present the status of miRNA-related research in several major biofuel crops and relevant model plants. We critically assess published research and suggest next steps for miRNA manipulation in feedstocks for increased biomass and sustainability for biofuels and bioproducts. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Management of mine spoil for crop productivity with lignite fly ash and biological amendments.

PubMed

Ram, L C; Srivastava, N K; Tripathi, R C; Jha, S K; Sinha, A K; Singh, G; Manoharan, V

2006-04-01

Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed.

Biosafety management and commercial use of genetically modified crops in China.

PubMed

Li, Yunhe; Peng, Yufa; Hallerman, Eric M; Wu, Kongming

2014-04-01

As a developing country with relatively limited arable land, China is making great efforts for development and use of genetically modified (GM) crops to boost agricultural productivity. Many GM crop varieties have been developed in China in recent years; in particular, China is playing a leading role in development of insect-resistant GM rice lines. To ensure the safe use of GM crops, biosafety risk assessments are required as an important part of the regulatory oversight of such products. With over 20 years of nationwide promotion of agricultural biotechnology, a relatively well-developed regulatory system for risk assessment and management of GM plants has been developed that establishes a firm basis for safe use of GM crops. So far, a total of seven GM crops involving ten events have been approved for commercial planting, and 5 GM crops with a total of 37 events have been approved for import as processing material in China. However, currently only insect-resistant Bt cotton and disease-resistant papaya have been commercially planted on a large scale. The planting of Bt cotton and disease-resistant papaya have provided efficient protection against cotton bollworms and Papaya ringspot virus (PRSV), respectively. As a consequence, chemical application to these crops has been significantly reduced, enhancing farm income while reducing human and non-target organism exposure to toxic chemicals. This article provides useful information for the colleagues, in particular for them whose mother tongue is not Chinese, to clearly understand the biosafety regulation and commercial use of genetically modified crops in China.

Inter- and intra-guild interactions related to aphids in nettle (Urtica dioica L.) strips closed to field crops.

PubMed

Alhmedi, A; Haubruge, E; Bodson, B; Francis, F

2006-01-01

A field experiment designed to assess the biodiversity related to nettle strips closed to crops, and more particularly the aphid and related beneficial populations, was established in experimental farm located in Gembloux (Belgium). Margin strips of nettle (Urtica dioica) closed to wheat (Triticum aestivum), green pea (Pisum sativum) and rape (Brassicae napus) fields were investigated. The diversity, abundance of aphids and related predators were analysed according to the plant crop species and the differential pesticide application (treated plot and control). Insects were visually observed every week during all the cultivation season. Two main families of aphidophagous predators were found in all field crops and nettle, the Coccinellidae and Syrphidae. The diversity of the aphidophagous predators was shown to be higher on nettle than in field crops, particularly the Chrysopidae, the Anthocoridae and the Miridae. However, a striking difference of ladybird abundance was observed according to the aphid host plant. In one side, Coccinella septempunctata was much more abundant on Acyrthosiphon pisum infested green pea than on the other host plant species. At the opposite, higher occurrence of Harmonia axyridis was observed on the aphid infested nettle plants than on the crop plants. In particular, none of H. axyridis was found in wheat crop. Also, more than only a significant positive correlation between predator and aphid abundance, specialised relations between particular aphid species and some so-called generalist predators was determined in the fields. Finally, intraguild interactions between the aphidophagous predators was assessed and shown that only a significant negative correlation between Episyrphus balteatus and H. axyridis related to the nettle aphid, Micrlophium carnosum, was observed. The relative distribution of the ladybirds, namely C. septempunctata and H. axyridis according to the host plant, nettle strips and crop plots was discussed in relation to integrated pest management approach.

One plant, two plants, three plants, four: does soil carbon respond to diversifying by one plant more? (Invited)

NASA Astrophysics Data System (ADS)

Grandy, S.

2013-12-01

Plant diversity is known to strongly influence aboveground ecosystem functions, but our understanding of its effects on belowground carbon (C) cycling has not kept pace. We know in broad terms that the belowground implications of reducing plant diversity include changes in soil nutrient cycling and biological communities, but remain uncertain about the specific links between plant diversity, soil microbial communities, and soil C cycling. Our knowledge gap is especially wide in agricultural systems, which comprise ~50% of the contiguous U.S. and differ from non-managed systems because diversity: (1) occurs primarily over time (i.e. crop rotations) rather than in space (i.e. inter-cropping); (2) exists as one of multiple management factors that potentially regulates soil C dynamics; and (3) is almost always low, with the addition or subtraction of a single plant species often representing a substantial change in diversity. I have been addressing the uncertain relationships between agricultural plant diversity and soil C cycling with a multi-tiered approach that includes a global meta-analysis, site-specific field manipulations, and intensive laboratory analyses. The meta-analysis using 122 studies shows that compared to single-crop monocultures, rotations increased soil microbial biomass C by 20.7% and microbial biomass N by 26.1% as well as total soil C and N. In a complimentary field study at the W.K. Kellogg Biological Station LTER Cropping Biodiversity Gradient Experiment we examined microbial communities, C cycling processes, and trace gas emissions in five rotation sequences varying in complexity from continuous corn monoculture to a five crop three-year rotation. Finding striking differences between monocultures and systems with more complex plant communities, these results confirm our meta-analysis, and highlight the strong effects of diversifying plant communities in agricultural systems. A complimentary lab study examining decomposition processes in monocultures and more diverse rotations shows that rotation soils process chemically complex C more rapidly. My studies point to complex relationships between the chemistry of substrate inputs and their fate in soils, while also emphasizing an important management consideration: maintaining soil biological functions and ecosystem services in managed agricultural systems requires the rotation of different crops, rather than the production of single crop monocultures.

A critical review on fungi mediated plant responses with special emphasis to Piriformospora indica on improved production and protection of crops.

PubMed

Ansari, Mohammad Wahid; Trivedi, Dipesh Kumar; Sahoo, Ranjan Kumar; Gill, Sarvajeet Singh; Tuteja, Narendra

2013-09-01

The beneficial fungi are potentially useful in agriculture sector to avail several services to crop plants such as water status, nutrient enrichment, stress tolerance, protection, weed control and bio-control. Natural agro-ecosystem relies on fungi because of it takes part in soil organic matter decomposition, nutrient acquisition, organic matter recycling, nutrient recycling, antagonism against plant pests, and crop management. The crucial role of fungi in normalizing the toxic effects of phenols, HCN and ROS by β-CAS, ACC demainase and antioxidant enzymes in plants is well documented. Fungi also play a part in various physiological processes such as water uptake, stomatal movement, mineral uptake, photosynthesis and biosynthesis of lignan, auxins and ethylene to improve growth and enhance plant fitness to cope heat, cold, salinity, drought and heavy metal stress. Here, we highlighted the ethylene- and cyclophilin A (CypA)-mediated response of Piriformospora indica for sustainable crop production under adverse environmental conditions. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Impact of insect management on population dynamics and insecticide resistance of tarnished plant bug (Lygus lineolaris)

USDA-ARS?s Scientific Manuscript database

The tarnished plant bug, Lygus lineolaris (Palisot De Beauvois) is a highly polyphagous insect that feeds on numerous wild and cultivated host plants. Although transgenic crops expressing insecticidal toxins have been available for approximately 20 years for some insect crop pests, none have been d...

Remote sensing in Virginia agriculture

NASA Technical Reports Server (NTRS)

Pettry, D. E.; Newhouse, M. E.; Dunton, E. M., Jr.; Scott, J. H., Jr.

1972-01-01

An experimental investigation, designed to develop and evaluate multispectral sensing techniques used in sensing agricultural crops, is described. Initial studies were designed to detect plant species and associated diseases, soil variations, and cultural practices under natural environment conditions. In addition, crop varieties, age, spacing, plant height, percentage of ground cover, and plant vigor are determined.

RESEARCH REPORT: USE OF VEGETATIVE VIGOR TEST TO DETECT EFFECTS OF LOW LEVELS OF HERBICIDES ON SELECTED NON-CROP PLANTS

EPA Science Inventory

To address the need for improved phytotoxicity testing protocols, we evaluated use of the vegetative vigor test methodology for use in determining effects of low concentrations of chemical herbicides on terrestrial non-crop plant species. Species included native plants from Illi...

7 CFR 457.140 - Dry pea crop insurance provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

...): (i) Interplanted with another crop; (ii) Planted into an established grass or legume; (iii) Planted...; (f) Earthquake; (g) Volcanic eruption; or (h) Failure of the irrigation water supply, if due to a... planting or replant payment will be owed. (h) All notices of damage must be provided to us not later than...

Biofertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity

PubMed Central

2014-01-01

Current soil management strategies are mainly dependent on inorganic chemical-based fertilizers, which caused a serious threat to human health and environment. The exploitation of beneficial microbes as a biofertilizer has become paramount importance in agriculture sector for their potential role in food safety and sustainable crop production. The eco-friendly approaches inspire a wide range of application of plant growth promoting rhizobacteria (PGPRs), endo- and ectomycorrhizal fungi, cyanobacteria and many other useful microscopic organisms led to improved nutrient uptake, plant growth and plant tolerance to abiotic and biotic stress. The present review highlighted biofertilizers mediated crops functional traits such as plant growth and productivity, nutrient profile, plant defense and protection with special emphasis to its function to trigger various growth- and defense-related genes in signaling network of cellular pathways to cause cellular response and thereby crop improvement. The knowledge gained from the literature appraised herein will help us to understand the physiological bases of biofertlizers towards sustainable agriculture in reducing problems associated with the use of chemicals fertilizers. PMID:24885352

How glyphosate affects plant disease development: it is more than enhanced susceptibility.

PubMed

Hammerschmidt, Ray

2018-05-01

Glyphosate has been shown to affect the development of plant disease in several ways. Plants utilize phenolic and other shikimic acid pathway-derived compounds as part of their defense against pathogens, and glyphosate inhibits the biosynthesis of these compounds via its mode of action. Several studies have shown a correlation between enhanced disease and suppression of phenolic compound production after glyphosate. Glyphosate-resistant crop plants have also been studied for changes in resistance as a result of carrying the glyphosate resistance trait. The evidence indicates that neither the resistance trait nor application of glyphosate to glyphosate-resistant plants increases susceptibility to disease. The only exceptions to this are cases where glyphosate has been shown to reduce rust diseases on glyphosate-resistant crops, supporting a fungicidal role for this chemical. Finally, glyphosate treatment of weeds or volunteer crops can cause a temporary increase in soil-borne pathogens that may result in disease development if crops are planted too soon after glyphosate application. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Fecundity of transgenic wild-crop hybrids of Cucurbita pepo (Cucurbitaceae): implications for crop-to-wild gene flow.

PubMed

Spencer, L J; Snow, A A

2001-06-01

Hybridization between crops and their weedy or wild relatives is an area of concern because the widespread use of genetically engineered crops may allow novel, beneficial transgenes to enter nearby populations. We compared fitness components of wild Cucurbita pepo from Arkansas, USA, with wild-crop hybrids derived from yellow squash (a cultivar of C. pepo with transgenic resistance to two viruses). Wild and hybrid progeny were grown in agricultural fields in Arkansas (1996-98) and Ohio (1996) in six similar experiments. Cross types (wild and hybrid) did not differ significantly in seedling survival, which exceeded 85% in all cases. In Ohio, where more detailed observations were made, hybrid plants produced 41% as many male flowers, 21% as many female flowers, and 28% as many seeds as wild plants. At all sites, flowering periods of the two cross types overlapped extensively. Putative virus symptoms were more common in wild plants than in hybrids. Lifetime fecundity varied considerably among sites and years. The average fecundity of hybrids ranged from 453 to 4497 seeds per plant and represented 15% - 53% of the numbers of seeds produced by wild plants in the same experiments. These results suggest that the F1 generation does not represent a strong barrier to the introgression of neutral or beneficial crop genes into free-living populations of C. pepo.

Breeding for plant heat tolerance at vegetative and reproductive stages.

PubMed

Driedonks, Nicky; Rieu, Ivo; Vriezen, Wim H

2016-06-01

Thermotolerant crop research. Global warming has become a serious worldwide threat. High temperature is a major environmental factor limiting crop productivity. Current adaptations to high temperature via alterations to technical and management systems are insufficient to sustain yield. For this reason, breeding for heat-tolerant crops is in high demand. This review provides an overview of the effects of high temperature on plant physiology, fertility and crop yield and discusses the strategies for breeding heat-tolerant cultivars. Generating thermotolerant crops seems to be a challenging task as heat sensitivity is highly variable across developmental stages and processes. In response to heat, plants trigger a cascade of events, switching on numerous genes. Although breeding has made substantial advances in developing heat-tolerant lines, the genetic basis and diversity of heat tolerance in plants remain largely unknown. The development of new varieties is expensive and time-consuming, and knowledge of heat tolerance mechanisms would aid the design of strategies to screen germplasm for heat tolerance traits. However, gains in heat tolerance are limited by the often narrow genetic diversity. Exploration and use of wild relatives and landraces in breeding can increase useful genetic diversity in current crops. Due to the complex nature of plant heat tolerance and its immediate global concern, it is essential to face this breeding challenge in a multidisciplinary holistic approach involving governmental agencies, private companies and academic institutions.

Suitability of non-lethal marker and marker-free systems for development of transgenic crop plants: present status and future prospects.

PubMed

Manimaran, P; Ramkumar, G; Sakthivel, K; Sundaram, R M; Madhav, M S; Balachandran, S M

2011-01-01

Genetically modified crops are one of the prudent options for enhancing the production and productivity of crop plants by safeguarding from the losses due to biotic and abiotic stresses. Agrobacterium-mediated and biolistic transformation methods are used to develop transgenic crop plants in which selectable marker genes (SMG) are generally deployed to identify 'true' transformants. The commonly used SMG obtained from prokaryotic sources when employed in transgenic plants pose risks due to their lethal nature during selection process. In the recent past, some non-lethal SMGs have been identified and used for selection of transformants with increased precision and high selection efficiency. Considering the concerns related to bio-safety of the environment, it is desirable to remove the SMG in order to maximize the commercial success through wide adoption and public acceptance of genetically modified (GM) food crops. In this review, we examine the availability, and the suitability of wide range of non-lethal selection markers and elimination of SMG methods to develop marker-free transgenics for achieving global food security. As the strategies for marker-free plants are still in proof-of-concept stage, adaptation of new genomics tools for identification of novel non-lethal marker systems and its application for developing marker-free transgenics would further strengthen the crop improvement program. Copyright © 2011 Elsevier Inc. All rights reserved.

Community Profiling of Fusarium in Combination with Other Plant-Associated Fungi in Different Crop Species Using SMRT Sequencing.

PubMed

Walder, Florian; Schlaeppi, Klaus; Wittwer, Raphaël; Held, Alain Y; Vogelgsang, Susanne; van der Heijden, Marcel G A

2017-01-01

Fusarium head blight, caused by fungi from the genus Fusarium , is one of the most harmful cereal diseases, resulting not only in severe yield losses but also in mycotoxin contaminated and health-threatening grains. Fusarium head blight is caused by a diverse set of species that have different host ranges, mycotoxin profiles and responses to agricultural practices. Thus, understanding the composition of Fusarium communities in the field is crucial for estimating their impact and also for the development of effective control measures. Up to now, most molecular tools that monitor Fusarium communities on plants are limited to certain species and do not distinguish other plant associated fungi. To close these gaps, we developed a sequencing-based community profiling methodology for crop-associated fungi with a focus on the genus Fusarium . By analyzing a 1600 bp long amplicon spanning the highly variable segments ITS and D1-D3 of the ribosomal operon by PacBio SMRT sequencing, we were able to robustly quantify Fusarium down to species level through clustering against reference sequences. The newly developed methodology was successfully validated in mock communities and provided similar results as the culture-based assessment of Fusarium communities by seed health tests in grain samples from different crop species. Finally, we exemplified the newly developed methodology in a field experiment with a wheat-maize crop sequence under different cover crop and tillage regimes. We analyzed wheat straw residues, cover crop shoots and maize grains and we could reveal that the cover crop hairy vetch ( Vicia villosa ) acts as a potent alternative host for Fusarium (OTU F.ave/tri ) showing an eightfold higher relative abundance compared with other cover crop treatments. Moreover, as the newly developed methodology also allows to trace other crop-associated fungi, we found that vetch and green fallow hosted further fungal plant pathogens including Zymoseptoria tritici . Thus, besides their beneficial traits, cover crops can also entail phytopathological risks by acting as alternative hosts for Fusarium and other noxious plant pathogens. The newly developed sequencing based methodology is a powerful diagnostic tool to trace Fusarium in combination with other fungi associated to different crop species.

Community Profiling of Fusarium in Combination with Other Plant-Associated Fungi in Different Crop Species Using SMRT Sequencing

PubMed Central

Walder, Florian; Schlaeppi, Klaus; Wittwer, Raphaël; Held, Alain Y.; Vogelgsang, Susanne; van der Heijden, Marcel G. A.

2017-01-01

Fusarium head blight, caused by fungi from the genus Fusarium, is one of the most harmful cereal diseases, resulting not only in severe yield losses but also in mycotoxin contaminated and health-threatening grains. Fusarium head blight is caused by a diverse set of species that have different host ranges, mycotoxin profiles and responses to agricultural practices. Thus, understanding the composition of Fusarium communities in the field is crucial for estimating their impact and also for the development of effective control measures. Up to now, most molecular tools that monitor Fusarium communities on plants are limited to certain species and do not distinguish other plant associated fungi. To close these gaps, we developed a sequencing-based community profiling methodology for crop-associated fungi with a focus on the genus Fusarium. By analyzing a 1600 bp long amplicon spanning the highly variable segments ITS and D1–D3 of the ribosomal operon by PacBio SMRT sequencing, we were able to robustly quantify Fusarium down to species level through clustering against reference sequences. The newly developed methodology was successfully validated in mock communities and provided similar results as the culture-based assessment of Fusarium communities by seed health tests in grain samples from different crop species. Finally, we exemplified the newly developed methodology in a field experiment with a wheat-maize crop sequence under different cover crop and tillage regimes. We analyzed wheat straw residues, cover crop shoots and maize grains and we could reveal that the cover crop hairy vetch (Vicia villosa) acts as a potent alternative host for Fusarium (OTU F.ave/tri) showing an eightfold higher relative abundance compared with other cover crop treatments. Moreover, as the newly developed methodology also allows to trace other crop-associated fungi, we found that vetch and green fallow hosted further fungal plant pathogens including Zymoseptoria tritici. Thus, besides their beneficial traits, cover crops can also entail phytopathological risks by acting as alternative hosts for Fusarium and other noxious plant pathogens. The newly developed sequencing based methodology is a powerful diagnostic tool to trace Fusarium in combination with other fungi associated to different crop species. PMID:29234337

Biotechnology: herbicide-resistant crops

USDA-ARS?s Scientific Manuscript database

Transgenic, herbicide-resistant (HR) crops are planted on about 80% of the land covered by transgenic crops. More than 90% of HR crios are glyphosate-resistant (GR) crops, the others being resistant to glufosinate. The wide-scale adoption of HR crops, largely for economic reasons, has been the mos...

Research and development of transgenic plants in Malaysia: an example from an Asian developing country.

PubMed

Hashim, Marzukhi; Osman, Mohamad; Abdullah, Ruslan; Pillai, Vilasini; Abu Bakar, Umi K; Hashim, Habibuddin; Daud, Hassan Mat

2002-12-01

In 2000, agriculture contributed 13% to the national gross domestic product of Malaysia. The country of 23 million people has created a competitive program coordinated by the Ministry of Science, Technology and the Environment, research institutions, and universities to undertake biotechnology research in several areas. Intensified research efforts are under way on oil palm, rubber, rice, papaya, and orchids. Although the most progress has been made in rice and papaya, no transgenic crop is ready for field trials. Nonetheless, preliminary steps have been taken to prepare for the trials, and detailed testing protocols are being developed.

Comparison of measured changes in seasonal soil water content by rainfed maize-bean intercrop and component cropping systems in a semi-arid region of southern Africa

NASA Astrophysics Data System (ADS)

Ogindo, H. O.; Walker, S.

Seasonal water content fluctuation within the effective root zone was monitored during the growing season for a maize-bean intercrop (IMB), sole maize (SM) and sole bean (SB) in Free State Province, Republic of South Africa. Comparisons were undertaken for progressive depths of extraction 0-300 mm; 300-600 mm and 600-900 mm respectively. These enabled the understanding of water extraction behavior of the cropping systems within the different soil layers including the topsoil surface normally influenced by soil surface evaporation. Additive intercrops have been known to conserve water, largely due to the early high leaf area index and the higher total leaf area. In this study, the combined effect of the intercrop components seemed to lower the total water demand by the intercrop compared to the sole crops. During the two seasons (2000/2001 and 2001/2002) the drained upper limit (DUL) and crop lower limits (CLL) were determined. The maize-bean intercrop, sole maize and sole bean had CLL of 141 mm/m, 149 mm/m and 159 mm/m respectively. The DUL was 262 mm/m for the site and therefore the potential plant extractable soil water for the cropping systems were: 121 mm/m (IMB); 114 mm/m (SM) and 103 mm/m (SB). Overall, the intercrop did not have significantly different total soil water extraction during both seasons, although it was additive, showing that it had higher water to biomass conversion.

Titanium as a Beneficial Element for Crop Production

PubMed Central

Lyu, Shiheng; Wei, Xiangying; Chen, Jianjun; Wang, Cun; Wang, Xiaoming; Pan, Dongming

2017-01-01

Titanium (Ti) is considered a beneficial element for plant growth. Ti applied via roots or leaves at low concentrations has been documented to improve crop performance through stimulating the activity of certain enzymes, enhancing chlorophyll content and photosynthesis, promoting nutrient uptake, strengthening stress tolerance, and improving crop yield and quality. Commercial fertilizers containing Ti, such as Tytanit and Mg-Titanit, have been used as biostimulants for improving crop production; however, mechanisms underlying the beneficial effects still remain unclear. In this article, we propose that the beneficial roles Ti plays in plants lie in its interaction with other nutrient elements primarily iron (Fe). Fe and Ti have synergistic and antagonistic relationships. When plants experience Fe deficiency, Ti helps induce the expression of genes related to Fe acquisition, thereby enhancing Fe uptake and utilization and subsequently improving plant growth. Plants may have proteins that either specifically or nonspecifically bind with Ti. When Ti concentration is high in plants, Ti competes with Fe for ligands or proteins. The competition could be severe, resulting in Ti phytotoxicity. As a result, the beneficial effects of Ti become more pronounced during the time when plants experience low or deficient Fe supply. PMID:28487709

Heavy metals effects on forage crops yields and estimation of elements accumulation in plants as affected by soil.

PubMed

Grytsyuk, N; Arapis, G; Perepelyatnikova, L; Ivanova, T; Vynograds'ka, V

2006-02-01

Heavy metals (Cu, Cd, Pb, Zn) effect on the productivity of forage crops (clover and perennial cereal grasses) and their accumulation in plants, depending on the concentration of these elements in a soil, has been studied in micro-field experiments on three types of soil. The principle objective was to determine regularities of heavy metals migration in a soil-plant system aiming the estimation of permissible levels of heavy metals content in soils with the following elaboration of methods, which regulate the toxicants transfer to plants. Methods of field experiments, agrochemical and atomic absorption analysis were used. Results were statistically treated by Statistica 6.0, S-Plus 6. Experimental results have shown that the intensity of heavy metals accumulation in plants depends on the type of the soil, the species of plants, the physicochemical properties of heavy metals and their content in the soil. Logarithmic interdependency of heavy metals concentration in soils and their accumulation in plants is suggested. However, the strong correlation between the different heavy metals concentrations in the various soils and the yield of crops was not observed. Toxicants accumulation in crops decreased in time.

The Value of Native Plants and Local Production in an Era of Global Agriculture.

PubMed

Shelef, Oren; Weisberg, Peter J; Provenza, Frederick D

2017-01-01

For addressing potential food shortages, a fundamental tradeoff exists between investing more resources to increasing productivity of existing crops, as opposed to increasing crop diversity by incorporating more species. We explore ways to use local plants as food resources and the potential to promote food diversity and agricultural resilience. We discuss how use of local plants and the practice of local agriculture can contribute to ongoing adaptability in times of global change. Most food crops are now produced, transported, and consumed long distances from their homelands of origin. At the same time, research and practices are directed primarily at improving the productivity of a small number of existing crops that form the cornerstone of a global food economy, rather than to increasing crop diversity. The result is a loss of agro-biodiversity, leading to a food industry that is more susceptible to abiotic and biotic stressors, and more at risk of catastrophic losses. Humans cultivate only about 150 of an estimated 30,000 edible plant species worldwide, with only 30 plant species comprising the vast majority of our diets. To some extent, these practices explain the food disparity among human populations, where nearly 1 billion people suffer insufficient nutrition and 2 billion people are obese or overweight. Commercial uses of new crops and wild plants of local origin have the potential to diversify global food production and better enable local adaptation to the diverse environments humans inhabit. We discuss the advantages, obstacles, and risks of using local plants. We also describe a case study-the missed opportunity to produce pine nuts commercially in the Western United States. We discuss the potential consequences of using local pine nuts rather than importing them overseas. Finally, we provide a list of edible native plants, and synthesize the state of research concerning the potential and challenges in using them for food production. The goal of our synthesis is to support more local food production using native plants in an ecologically sustainable manner.

Gene Editing in Polyploid Crops: Wheat, Camelina, Canola, Potato, Cotton, Peanut, Sugar Cane, and Citrus.

PubMed

Weeks, Donald P

2017-01-01

Polyploid crops make up a significant portion of the major food and fiber crops of the world and include wheat, potato, cotton, apple, peanut, citrus, and brassica oilseeds such as rape, canola, and Camelina. The presence of three sets of chromosomes in triploids, four sets in tetraploids, and six sets in hexaploids present significant challenges to conventional plant breeding and, potentially, to efficient use of rapidly emerging gene and genome-editing systems such as zinc finger nucleases, single-stranded oligonucleotides, TALE effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR/Cas9). However, recent studies with each of these techniques in several polyploid crops have demonstrated facile editing of some or all of the genes targeted for modification on homeologous chromosomes. These modifications have allowed improvements in food nutrition, seed oil composition, disease resistance, weed protection, plant breeding procedures, and food safety. Plants and plant products exhibiting useful new traits created through gene editing but lacking foreign DNA may face reduced regulatory restrictions. Such plants can be obtained either by simply selecting for null segregants that have lost their editing transgenes during plant breeding or, even more attractively, by delivery of biodegradable Cas9/sgRNA ribonucleoprotein complexes (i.e., no DNA) into plant cells where they are expressed only transiently but allow for efficient gene editing-a system that has been recently demonstrated in at least two polyploid crops. Such systems that create precise mutations but leave no transgene footprint hold potential promise for assisting with the elimination or great diminution of regulatory processes that presently burden approvals of conventional transgenic crops. © 2017 Elsevier Inc. All rights reserved.

Limited Fitness Advantages of Crop-Weed Hybrid Progeny Containing Insect-Resistant Transgenes (Bt/CpTI) in Transgenic Rice Field

PubMed Central

Yang, Xiao; Wang, Feng; Su, Jun; Lu, Bao-Rong

2012-01-01

Background The spread of insect-resistance transgenes from genetically engineered (GE) rice to its coexisting weedy rice (O. sativa f. spontanea) populations via gene flow creates a major concern for commercial GE rice cultivation. Transgene flow to weedy rice seems unavoidable. Therefore, characterization of potential fitness effect brought by the transgenes is essential to assess environmental consequences caused by crop-weed transgene flow. Methodology/Principal Findings Field performance of fitness-related traits was assessed in advanced hybrid progeny of F4 generation derived from a cross between an insect-resistant transgenic (Bt/CpTI) rice line and a weedy strain. The performance of transgene-positive hybrid progeny was compared with the transgene-negative progeny and weedy parent in pure and mixed planting of transgenic and nontransgenic plants under environmental conditions with natural vs. low insect pressure. Results showed that under natural insect pressure the insect-resistant transgenes could effectively suppress target insects and bring significantly increased fitness to transgenic plants in pure planting, compared with nontransgenic plants (including weedy parent). In contrast, no significant differences in fitness were detected under low insect pressure. However, such increase in fitness was not detected in the mixed planting of transgenic and nontransgenic plants due to significantly reduced insect pressure. Conclusions/Significance Insect-resistance transgenes may have limited fitness advantages to hybrid progeny resulted from crop-weed transgene flow owning to the significantly reduced ambient target insect pressure when an insect-resistant GE crop is grown. Given that the extensive cultivation of an insect-resistant GE crop will ultimately reduce the target insect pressure, the rapid spread of insect-resistance transgenes in weedy populations in commercial GE crop fields may be not likely to happen. PMID:22815975

7 CFR 457.109 - Sugar Beet Crop Insurance Provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Interplanted with another crop; (ii) Planted into an established grass or legume; or (iii) Planted prior to... eruption; or (h) Failure of the irrigation water supply, if caused by an insured peril that occurs during...

7 CFR 457.109 - Sugar Beet Crop Insurance Provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Interplanted with another crop; (ii) Planted into an established grass or legume; or (iii) Planted prior to... eruption; or (h) Failure of the irrigation water supply, if caused by an insured peril that occurs during...

Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management

PubMed Central

Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

2015-01-01

Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3 --N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha-1 biomass, whereas mixtures averaged 4.1 Mg ha-1 and hairy vetch 2.3 Mg ha-1. Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha-1 N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3 --N (0 to 30 cm depth) averaged 62 kg ha-1 for rye, 97 kg ha-1 for the mixtures, and 119 kg ha-1 for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures. PMID:26080008

Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

PubMed

Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

2015-01-01

Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3(-)-N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha(-1) biomass, whereas mixtures averaged 4.1 Mg ha(-1) and hairy vetch 2.3 Mg ha(-1). Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha(-1) N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3(-)-N (0 to 30 cm depth) averaged 62 kg ha(-1) for rye, 97 kg ha(-1) for the mixtures, and 119 kg ha(-1) for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures.

Challenges and opportunities for quantifying roots and rhizosphere interactions through imaging and image analysis.

PubMed

Downie, H F; Adu, M O; Schmidt, S; Otten, W; Dupuy, L X; White, P J; Valentine, T A

2015-07-01

The morphology of roots and root systems influences the efficiency by which plants acquire nutrients and water, anchor themselves and provide stability to the surrounding soil. Plant genotype and the biotic and abiotic environment significantly influence root morphology, growth and ultimately crop yield. The challenge for researchers interested in phenotyping root systems is, therefore, not just to measure roots and link their phenotype to the plant genotype, but also to understand how the growth of roots is influenced by their environment. This review discusses progress in quantifying root system parameters (e.g. in terms of size, shape and dynamics) using imaging and image analysis technologies and also discusses their potential for providing a better understanding of root:soil interactions. Significant progress has been made in image acquisition techniques, however trade-offs exist between sample throughput, sample size, image resolution and information gained. All of these factors impact on downstream image analysis processes. While there have been significant advances in computation power, limitations still exist in statistical processes involved in image analysis. Utilizing and combining different imaging systems, integrating measurements and image analysis where possible, and amalgamating data will allow researchers to gain a better understanding of root:soil interactions. © 2014 John Wiley & Sons Ltd.

Integrating Plant Science and Crop Modeling: Assessment of the Impact of Climate Change on Soybean and Maize Production.

PubMed

Fodor, Nándor; Challinor, Andrew; Droutsas, Ioannis; Ramirez-Villegas, Julian; Zabel, Florian; Koehler, Ann-Kristin; Foyer, Christine H

2017-11-01

Increasing global CO2 emissions have profound consequences for plant biology, not least because of direct influences on carbon gain. However, much remains uncertain regarding how our major crops will respond to a future high CO2 world. Crop model inter-comparison studies have identified large uncertainties and biases associated with climate change. The need to quantify uncertainty has drawn the fields of plant molecular physiology, crop breeding and biology, and climate change modeling closer together. Comparing data from different models that have been used to assess the potential climate change impacts on soybean and maize production, future yield losses have been predicted for both major crops. When CO2 fertilization effects are taken into account significant yield gains are predicted for soybean, together with a shift in global production from the Southern to the Northern hemisphere. Maize production is also forecast to shift northwards. However, unless plant breeders are able to produce new hybrids with improved traits, the forecasted yield losses for maize will only be mitigated by agro-management adaptations. In addition, the increasing demands of a growing world population will require larger areas of marginal land to be used for maize and soybean production. We summarize the outputs of crop models, together with mitigation options for decreasing the negative impacts of climate on the global maize and soybean production, providing an overview of projected land-use change as a major determining factor for future global crop production. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

Transgenic salt-tolerant tomato plants accumulate salt in foliage but not in fruit.

PubMed

Zhang, H X; Blumwald, E

2001-08-01

Transgenic tomato plants overexpressing a vacuolar Na+/H+ antiport were able to grow, flower, and produce fruit in the presence of 200 mM sodium chloride. Although the leaves accumulated high sodium concentrations, the tomato fruit displayed very low sodium content. Contrary to the notion that multiple traits introduced by breeding into crop plants are needed to obtain salt-tolerant plants, the modification of a single trait significantly improved the salinity tolerance of this crop plant. These results demonstrate that with a combination of breeding and transgenic plants it could be possible to produce salt-tolerant crops with far fewer target traits than had been anticipated. The accumulation of sodium in the leaves and not in the fruit demonstrates the utility of such a modification in preserving the quality of the fruit.

Strategies for Enhanced Crop Resistance to Insect Pests.

PubMed

Douglas, Angela E

2018-04-29

Insect pests are responsible for substantial crop losses worldwide through direct damage and transmission of plant diseases, and novel approaches that complement or replace broad-spectrum chemical insecticides will facilitate the sustainable intensification of food production in the coming decades. Multiple strategies for improved crop resistance to insect pests, especially strategies relating to plant secondary metabolism and immunity and microbiome science, are becoming available. Recent advances in metabolic engineering of plant secondary chemistry offer the promise of specific toxicity or deterrence to insect pests; improved understanding of plant immunity against insects provides routes to optimize plant defenses against insects; and the microbiomes of insect pests can be exploited, either as a target or as a vehicle for delivery of insecticidal agents. Implementation of these advances will be facilitated by ongoing advances in plant breeding and genetic technologies.

Proteomics and plant disease: advances in combating a major threat to the global food supply.

PubMed

Rampitsch, Christof; Bykova, Natalia V

2012-02-01

The study of plant disease and immunity is benefiting tremendously from proteomics. Parallel streams of research from model systems, from pathogens in vitro and from the relevant pathogen-crop interactions themselves have begun to reveal a model of how plants succumb to invading pathogens and how they defend themselves without the benefit of a circulating immune system. In this review, we discuss the contribution of proteomics to these advances, drawing mainly on examples from crop-fungus interactions, from Arabidopsis-bacteria interactions, from elicitor-based model systems and from pathogen studies, to highlight also the important contribution of non-crop systems to advancing crop protection. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Watershed-Scale Cover Crops Reduce Nutrient Export From Agricultural Landscapes.

NASA Astrophysics Data System (ADS)

Tank, J. L.; Hanrahan, B.; Christopher, S. F.; Trentman, M. T.; Royer, T. V.; Prior, K.

2016-12-01

The Midwestern US has undergone extensive land use change as forest, wetlands, and prairies have been converted to agroecosystems. Today, excess fertilizer nutrients from farm fields enter Midwestern agricultural streams, which degrades both local and downstream water quality, resulting in algal blooms and subsequent hypoxic "dead zones" far from the nutrient source. We are quantifying the benefits of watershed-scale conservation practices that may reduce nutrient runoff from adjacent farm fields. Specifically, research is lacking on whether the planting of winter cover crops in watersheds currently dominated by row-crop agriculture can significantly reduce nutrient inputs to adjacent streams. Since 2013, farmers have planted cover crops on 70% of croppable acres in the Shatto Ditch Watershed (IN), and "saturation level" implementation of this conservation practice has been sustained for 3 years. Every 14 days, we have quantified nutrient loss from fields by sampling nutrient fluxes from multiple subsurface tile drains and longitudinally along the stream channel throughout the watershed. Cover crops improved stream water quality by reducing dissolved inorganic nutrients exported downstream; nitrate-N and DRP concentrations and fluxes were significantly lower in tiles draining fields with cover crops compared to those without. Annual watershed nutrient export also decreased, and reductions in N and P loss ( 30-40%) exceeded what we expected based on only a 6-10% reduction in runoff due to increased watershed water holding capacity. We are also exploring the processes responsible for increased nutrient retention, where they are occurring (terrestrial vs. aquatic) and when (baseflow vs. storms). For example, whole-stream metabolism also responded to cover crop planting, showing reduced variation in primary production and respiration in years after watershed-scale planting of cover crops. In summary, widespread land cover change, through cover crop planting, can significantly reduce annual watershed-scale nutrient export. Moreover, successful outcomes highlighted through demonstration projects may facilitate widespread adoption, making them powerful agents of change for advancing conservation success.

Spatial and spectral simulation of LANDSAT images of agricultural areas

NASA Technical Reports Server (NTRS)

Pont, W. F., Jr. (Principal Investigator)

1982-01-01

A LANDSAT scene simulation capability was developed to study the effects of small fields and misregistration on LANDSAT-based crop proportion estimation procedures. The simulation employs a pattern of ground polygons each with a crop ID, planting date, and scale factor. Historical greenness/brightness crop development profiles generate the mean signal values for each polygon. Historical within-field covariances add texture to pixels in each polygon. The planting dates and scale factors create between-field/within-crop variation. Between field and crop variation is achieved by the above and crop profile differences. The LANDSAT point spread function is used to add correlation between nearby pixels. The next effect of the point spread function is to blur the image. Mixed pixels and misregistration are also simulated.

Evolution of crop production under a pseudo-space environment using model plants, Lotus japonicus

NASA Astrophysics Data System (ADS)

Tomita-Yokotani, Kaori; Motohashi, Kyohei; Omi, Naomi; Sato, Seigo; Aoki, Toshio; Hashimoto, Hirofumi; Yamashita, Masamichi

Habitation in outer space is one of our challenges. We have been studying space agriculture and/or spacecraft agriculture to provide food and oxygen for the habitation area in the space environment. However, careful investigation should be made concerning the results of exotic environmental effects on the endogenous production of biologically active substances in indi-vidual cultivated plants in a space environment. We have already reported that the production of functional substances in cultivated plants as crops are affected by gravity. The amounts of the main physiological substances in these plants grown under terrestrial control were different from that grown in a pseudo-microgravity. These results suggested that the nutrition would be changed in the plants/crops grown in the space environment when human beings eat in space. This estimation required us to investigate each of the useful components produced by each plant grown in the space environment. These estimations involved several study fields, includ-ing nutrition, plant physiology, etc. On the other hand, the analysis of model plant genomes has recently been remarkably advanced. Lotus japonicus, a leguminous plant, is also one of the model plant. The leguminosae is a large family in the plant vegetable kingdom and almost the entire genome sequence of Lotus japonicus has been determined. Nitrogen fixation would be possible even in a space environment. We are trying to determine the best conditions and evolution for crop production using the model plants.

The Use of Proteomic Tools to Address Challenges Faced in Clonal Propagation of Tropical Crops through Somatic Embryogenesis.

PubMed

Chin, Chiew Foan; Tan, Hooi Sin

2018-05-04

In many tropical countries with agriculture as the mainstay of the economy, tropical crops are commonly cultivated at the plantation scale. The successful establishment of crop plantations depends on the availability of a large quantity of elite seedling plants. Many plantation companies establish plant tissue culture laboratories to supply planting materials for their plantations and one of the most common applications of plant tissue culture is the mass propagation of true-to-type elite seedlings. However, problems encountered in tissue culture technology prevent its applications being widely adopted. Proteomics can be a powerful tool for use in the analysis of cultures, and to understand the biological processes that takes place at the cellular and molecular levels in order to address these problems. This mini review presents the tissue culture technologies commonly used in the propagation of tropical crops. It provides an outline of some the genes and proteins isolated that are associated with somatic embryogenesis and the use of proteomic technology in analysing tissue culture samples and processes in tropical crops.

Balancing Immunity and Yield in Crop Plants.

PubMed

Ning, Yuese; Liu, Wende; Wang, Guo-Liang

2017-12-01

Crop diseases cause enormous yield losses and threaten global food[ED1] security. The use of highly resistant cultivars can effectively control plant diseases, but in crops, genetic immunity to disease often comes with an unintended reduction in growth and yield. Here, we review recent advances in understanding how nucleotide-binding domain, leucine-rich repeat (NLR) receptors and cell wall-associated kinase (WAK) proteins function in balancing immunity and yield. We also discuss the role of plant hormones and transcription factors in regulating the trade-offs between plant growth and immunity. Finally, we describe how a novel mechanism of translational control of defense proteins can enhance immunity without the reduction in fitness. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evidence for the role of an invasive weed in widespread occurrence of phytoplasmal diseases in diverse vegetable crops: implications from lineage-specific molecular markers

USDA-ARS?s Scientific Manuscript database

During the period from 2011 to 2013, several plant diseases repeatedly occurred in vegetable crops grown in Yuanmou County, Yunnan Province, China. Affected plants included cowpea, sword bean, string bean, tomato, lettuce, and water spinach. The diseased plants exhibited symptoms of witches’-broom...

Double strand RNA oral delivery methods to induce RNA interference in phloem and plant-sap-feeding insects

USDA-ARS?s Scientific Manuscript database

Phloem and plant sap feeding insect pests invade the integrity of crops and fruits to retrieve nutrients in the process damaging food productivity. Hemipteran insects account for a number of economically substantial pests of plants that cause damage to crops by feeding on phloem sap. Halyomorpha hal...

Ground cover management in walnut and other hardwood plantings

Treesearch

J.W. Van Sambeek; H.E. Garrett

2004-01-01

Ground cover management in walnut plantings and established stands can include (1) manipulating the resident vegetation, (2) mechanical control, (3) chemical control, (4) mulching, (5) planting cover crops, or (6) interplanting woody nurse crops. Data from over 110 reports were used to compile a database that compared growth of black walnut and other hardwoods under...

Advancing Crop Transformation in the Era of Genome Editing

USDA-ARS?s Scientific Manuscript database

Plant transformation has enabled fundamental insights into plant biology and revolutionized commercial agriculture. Unfortunately, for most crops, transformation and regeneration remain arduous even after more than thirty years of technological advances. Genome editing provides new opportunities to...

Plant Productivity and Characterization of Zeoponic Substrates after Three Successive Crops of Radish (Raphanus sativus L.)

NASA Technical Reports Server (NTRS)

Gruener, J. E.; Ming, Douglas W.; Galindo, C., Jr.; Henderson, K. E.; Golden, D. C.

2007-01-01

The National Aeronautics and Space Administration (NASA) has developed a zeolite-based synthetic substrate, termed zeoponics. The zeoponic substrate (consisting of NH4(-) and K-exchanged clinoptilolite, synthetic apatite, and dolomite) provides all of the plant-essential nutrients through mineral dissolution and ion exchange, with only the addition of water. Previous studies have shown high productivity of wheat in zeoponic substrates; however, no experiments have been conducted on other crops. The objective of this study was to determine the productivity and nutrient uptake of radish (Raphanus sativus L.) grown in zeoponic substrates with three successive crops in the same substrate. Radish was chosen because of its sensitivities to NH4(+). Average fresh weights of edible roots were similar for radish grown in zeoponic substrates watered with deionized H2O (10.97 g/plant) and in potting mix control substrate irrigated with nutrient solution (10.92 g/plant). Average fresh weight production of edible roots for radish grown in same zeoponic substrate increased in yield over time with the lowest yield in the first crop (7.10 g/plant) and highest in the third crop (13.90 g/plant). The Ca plant tissue levels in radishes (1.8-2.9 wt. %) grown in zeoponic substrates are lower than the suggested sufficient range of 3.0-4.5 wt. % Ca; however, the Ca level is highest (2.9 wt. %) in radishes grown in the third crop in the same zeoponic substrates. The higher radish yield in the third crop was attributed to a reduction in an NH4(-) induced Ca deficiency that has been previously described for wheat grown in zeoponic substrates. The P levels in plant tissues of radish grown in the zeoponic substrates ranged from 0.94-1.15 wt. %; which is slightly higher than the sufficient levels of 0.3-0.7 wt. %. With the exception of Ca and P, other macronutrient and micronutrient levels in radish grown in zeoponic substrates were well within the recommended sufficient ranges. After three successive crops of radish growth, the zeoponic substrates had 52% of the original NH4(-)N and 78% of the original K remaining on zeolite exchange sites. Zeoponic substrates are capable of long-term productivity of radishes for space.

Domestication impacts on plant–herbivore interactions: a meta-analysis

PubMed Central

Poveda, Katja

2017-01-01

For millennia, humans have imposed strong selection on domesticated crops, resulting in drastically altered crop phenotypes compared with wild ancestors. Crop yields have increased, but a long-held hypothesis is that domestication has also unintentionally decreased plant defences against herbivores. To test this hypothesis, we conducted a phylogenetically controlled meta-analysis comparing insect herbivore resistance and putative plant defence traits between crops and their wild relatives. Our database included 2098 comparisons made across 73 crops in 89 studies. We found that domestication consistently reduced plant resistance to herbivores, although the magnitude of the effects varied across plant organs and depended on how resistance was measured. However, domestication had no consistent effects on the specific plant defence traits underlying resistance, including secondary metabolites and physical feeding barriers. The values of these traits sometimes increased and sometimes decreased during domestication. Consistent negative effects of domestication were observed only when defence traits were measured in reproductive organs or in the plant organ that was harvested. These results highlight the complexity of evolution under domestication and the need for an improved theoretical understanding of the mechanisms through which agronomic selection can influence the species interactions that impact both the yield and sustainability of our food systems. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’. PMID:27920379

Fabrication Of Biogenic Silver Nanoparticles Using Agricultural Crop Plant Leaf Extracts

NASA Astrophysics Data System (ADS)

Rajani, P.; SriSindhura, K.; Prasad, T. N. V. K. V.; Hussain, O. M.; Sudhakar, P.; Latha, P.; Balakrishna, M.; Kambala, V.; Reddy, K. Raja

2010-10-01

Nanoparticles are being viewed as fundamental building blocks of nanotechnology. Biosynthesis of nanoparticles by plant extracts is currently under exploitation. Use of agricultural crop plant extracts for synthesis of metal nanoparticles would add a new dimension to the agricultural sector in the utilization of crop waste. Silver has long been recognized as having an inhibitory effect towards many bacterial strains and microorganisms commonly present in medical and industrial processes. Four pulse crop plants and three cereal crop plants (Vigna radiata, Arachis hypogaea, Cyamopsis tetragonolobus, Zea mays, Pennisetum glaucum, Sorghum vulgare) were used and compared for their extra cellular synthesis of metallic silver nanoparticles. Stable silver nanoparticles were formed by treating aqueous solution of AgNO3 with the plant leaf extracts as reducing agent at temperatures 50 °C-95 °C. UV-Visible spectroscopy was utilized to monitor the formation of silver nanoparticles. XRD analysis of formed silver nanoparticles revealed face centered cubic structure with (111), (200), (220) and (311) planes. SEM and EDAX analysis confirm the size of the formed silver nanoparticles to be in the range of 50-200 nm. Our proposed work offers a enviro-friendly method for biogenic silver nanoparticles production. This could provide a faster synthesis rate comparable to those of chemical methods and potentially be used in areas such as cosmetics, food and medical applications.

Variation of Bacterial Community Diversity in Rhizosphere Soil of Sole-Cropped versus Intercropped Wheat Field after Harvest.

PubMed

Yang, Zhenping; Yang, Wenping; Li, Shengcai; Hao, Jiaomin; Su, Zhifeng; Sun, Min; Gao, Zhiqiang; Zhang, Chunlai

2016-01-01

As the major crops in north China, spring crops are usually planted from April through May every spring and harvested in fall. Wheat is also a very common crop traditionally planted in fall or spring and harvested in summer year by year. This continuous cropping system exhibited the disadvantages of reducing the fertility of soil through decreasing microbial diversity. Thus, management of microbial diversity in the rhizosphere plays a vital role in sustainable crop production. In this study, ten common spring crops in north China were chosen sole-cropped and four were chosen intercropped with peanut in wheat fields after harvest. Denaturing gradient gel electrophoresis (DGGE) and DNA sequencing of one 16S rDNA fragment were used to analyze the bacterial diversity and species identification. DGGE profiles showed the bacterial community diversity in rhizosphere soil samples varied among various crops under different cropping systems, more diverse under intercropping system than under sole-cropping. Some intercropping-specific bands in DGGE profiles suggested that several bacterial species were stimulated by intercropping systems specifically. Furthermore, the identification of these dominant and functional bacteria by DNA sequencing indicated that intercropping systems are more beneficial to improve soil fertility. Compared to intercropping systems, we also observed changes in microbial community of rhizosphere soil under sole-crops. The rhizosphere bacterial community structure in spring crops showed a strong crop species-specific pattern. More importantly, Empedobacter brevis, a typical plant pathogen, was only found in the carrot rhizosphere, suggesting carrot should be sown prudently. In conclusion, our study demonstrated that crop species and cropping systems had significant effects on bacterial community diversity in the rhizosphere soils. We strongly suggest sorghum, glutinous millet and buckwheat could be taken into account as intercropping crops with peanut; while hulled oat, mung bean or foxtail millet could be considered for sowing in wheat fields after harvest in North China.

Winter rye cover crop effect on corn seedling pathogens

USDA-ARS?s Scientific Manuscript database

Cover crops have been grown successfully in Iowa, but sometimes a cereal rye cover crop preceding corn can reduce corn yields. Our research examines the effect of a rye cover crop on infections of the succeeding corn crop by soil fungal pathogens. Plant measurements included: growth stage, height, r...

Cellulosic Biofuel Production with Winter Cover Crops: Yield and Nitrogen Implications

USDA-ARS?s Scientific Manuscript database

Interest in renewable energy sources derived from plant biomass is increasing. Growing cover crops after harvest of the primary crop has been proposed as a solution to producing cellulosic biomass on existing crop-producing land without reducing food-harvest potential. Growing cover crops is a recom...

Bt crops: predicting effects of escaped transgenes on the fitness of wild plants and their herbivores.

PubMed

Letourneau, Deborah K; Robinson, Gaden S; Hagen, Joy A

2003-01-01

One prominent concern about genetically modified crops is the possibility of environmental impacts from the movement of fitness-enhancing traits to wild plant populations. Decisions to deregulate Bt crops in the USA have relied strongly on arguments that these crops will not interbreed with wild relatives in the permitted growing regions. Limited attention therefore has been directed to analyses of the consequences of gene flow. To provide a transparent evaluation process for risks associated with insecticidal transgene escape, we crafted a series of questions designed to guide this aspect of the risk assessment. We then explored the current knowledge base available for answering such risk-related questions for three Bt crops (cotton, rapeseed, and rice). First, we generated a list of wild relatives of these crops. A definitive list of potential transgene recipients is not yet possible for some crops. Sufficient data are not available for some crops to eliminate certain related plant species from consideration of fertile hybrid formation, thus making lists for these crops subject to speculation. Second, we queried the HOSTS database (UK) to obtain a worldwide listing of lepidopteran species that feed on these crops and their wild relatives, and to determine the host range of the larvae. To our knowledge, this list of 502 lepidopteran species is the first such list published for these crops and wild crop relatives. Third, we used a data set maintained by the Canadian Forest Service to assess Bt toxin susceptibility for these lepidopterans. Only 3% of those species have been tested for susceptibility; and the literature suggests that generalizations about susceptibility among taxa are difficult due to the variability within families. Fourth, we consulted the literature to interpret what is known about the ability of lepidopterans to regulate plant fitness or invasiveness. We could not eliminate the possibility of ecological release due to plant resistance against lepidopterans. In fact, there is strong experimental evidence that lepidopteran herbivores do limit the distribution and/or abundances of at least some wild plant species. Neither could we eliminate the possibility that non-target lepidopterans might have important functions in the ecosystem as pollinators or alternate hosts to natural enemies of pest species. This study suggests that crucial data are lacking for the development of a credible scientific basis to confirm or deny environmental risks associated with the escape of Bt transgene constructs to wild relatives. Given the absence of information on the identity, level of susceptibility, and ecological roles of lepidopterans exploiting specific wild relatives of Bt crops, we suggest that new efforts be directed to assessing possible consequences of lepidopteran mortality on resistant wild relatives.

Changes in ecosystem services associated with planting structures of cropland: A case study in Minle County in China

NASA Astrophysics Data System (ADS)

Liu, Yaqun; Song, Wei; Mu, Fengyun

2017-12-01

The cropland ecosystem provides essential direct and indirect products and services to mankind such as food, fiber, biodiversity and soil conservation. A change of crop planting structure can change the ecosystem services of cropland by affecting land use type. In recent years, under the influence of regional comparative advantage and consumer demand changes, the crop planting structure in China has changed rapidly. However, there is still a lack of deep understanding on the effect of such a change in planting structure on the ecosystem services of cropland. Therefore, this research selected Minle County in the Heihe River Basin, which has small scattered croplands and a complex planting structure, as a study area. Based on the key time phase and optimal threshold of the normalized difference vegetation index (NDVI) data of the Thematic Mapper and Enhanced Thematic Mapper Plus (TM/ETM+) images, this study used the decision tree algorithm to classify and extract the crop planting structure in Minle County in 2007 and 2012 and to analyze the changes in its temporal and spatial patterns. Then, the market value method was adopted to estimate the effect of the change in crop planting structure on the ecosystem services of the cropland. From 2007 to 2012, the planting area of corn and rapeseed in Minle County increased by 5.86 × 103 ha and 5.10 × 103 ha, respectively. Conversely, the planting area of wheat and barley was reduced by 3.26 × 103 ha and 6.34 × 103 ha, respectively. These changes directly caused the increase of the ecosystem services value of corn and rapeseed by 1062.82 × 104 USD and 842.54 × 104 USD, respectively. The resulting reduction in the ecosystem services value of wheat and barley was 488.24 × 104 USD and 828.29 × 104 USD, respectively. Besides, the total ecosystem services value of cropland increased by 1564.98 × 104 USD. Further analysis found that the change in the crop planting structure caused an increase in the ecosystem services value of cropland of 359.44 × 104 USD, with a contribution rate of 22.97% to the total increase. The expansion of corn caused the increase of the ecosystem services value of cropland by 151.65 × 104 USD, with a contribution rate of 9.69% to the total increase. The change in crop planting structure in Minle County increased not only the economic benefits of crop planting, but also the ecosystem services of cropland.

Capability of selected crop plants for shoot mercury accumulation from polluted soils: phytoremediation perspectives.

PubMed

Rodriguez, Luis; Rincón, Jesusa; Asencio, Isaac; Rodríguez-Castellanos, Laura

2007-01-01

High-biomass crops can be considered as an alternative to hyperaccumulator plants to phytoremediate soils contaminated by heavy metals. In order to assess their practical capability for the absorption and accumulation of Hg in shoots, barley, white lupine, lentil, and chickpea were tested in pot experiments using several growth substrates. In the first experimental series, plants were grown in a mixture of vermiculite and perlite spiked with 8.35 microg g(-1) d.w. of soluble Hg. The mercury concentration of the plants' aerial tissues ranged from 1.51 to 5.13 microg g(-1) d.w. with lentil and lupine showing the highest values. In a second experiment carried out using a Hg-polluted soil (32.16 microg g(-1) d.w.) collected from a historical mining area (Almadén, Spain), the crop plants tested only reached shoot Hg concentration up to 1.13 microg g(-1) d.w. In the third experimental series, the Almadén soil was spiked with 1 microg g(-1) d.w. of soluble Hg; as a result, mercury concentrations in the plant shoots increased approximately 6 times for lupine, 5 times for chickpea, and 3.5 times for barley and lentil, with respect to those obtained with the original soil without Hg added. This marked difference was attributed to the low availability of Hg in the original Almadin soil and its subsequent increase in the Hg-spiked soil. The low mercury accumulation yields obtained for all plants do not make a successful decontamination of the Almadén soils possible byphytoremediation using crop plants. However, since the crops tested can effectively decrease the plant-available Hg level in this soil, their use could, to some extent, reduce the environmental risk of Hg pollution in the area.

Reproductive traits and evolutionary divergence between Mediterranean crops and their wild relatives.

PubMed

Iriondo, J M; Milla, R; Volis, S; Rubio de Casas, R

2018-01-01

Changes in reproductive traits associated with domestication critically determine the evolutionary divergence between crops and their wild relatives, as well as the potential of crop plants to become feral. In this review, we examine the genetic mechanisms of plant domestication and the different types of selection involved, and describe the particularities of domestication of Mediterranean field crops with regard to their reproductive traits, showing illustrative examples. We also explore gene flow patterns between Mediterranean field crops and their wild relatives, along with their ecological, evolutionary and economic implications. Domestication entails multiple selective processes, including direct selection, environmental adaptation and developmental constraints. In contrast to clonal propagation in perennials, sexual reproduction and seed propagation in annuals and biennials have led to a distinct pathway of evolution of reproductive traits. Thus, the initial domestication and further breeding of Mediterranean field crops has brought about changes in reproductive traits, such as higher mean values and variance of seed and fruit sizes, reduced fruit and seed toxicity, non-shattering seeds and loss of seed dormancy. Evolution under domestication is not a linear process, and bi-directional gene flow between wild and crop taxa is a frequent phenomenon. Thus, hybridisation and introgression have played a very important role in determining the genetics of current cultivars. In turn, gene flow from crops to wild relatives can lead to introgression of crop genes into wild populations and potentially alter the characteristics of natural communities. In conclusion, plant evolution under domestication has not only changed the reproductive biology of cultivated taxa, its effects are multifaceted and have implications beyond agriculture. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

Mini-review of knowledge gaps in salt tolerance of plants applied to willows and poplars

Treesearch

Jaconette Mirck; Ronald S. Zalesny

2015-01-01

Salt tolerance of agricultural crops has been studied since the 1940, but knowledge regarding salt tolerance of woody crops is still in its initial phase. Salt tolerance of agricultural crops has been expressed as the yield decrease due to a certain salt concentration within the root zone as compared to a non-saline control. The most well-known plant response curve to...

A Proteomic View on the Role of Legume Symbiotic Interactions

PubMed Central

Larrainzar, Estíbaliz; Wienkoop, Stefanie

2017-01-01

Legume plants are key elements in sustainable agriculture and represent a significant source of plant-based protein for humans and animal feed worldwide. One specific feature of the family is the ability to establish nitrogen-fixing symbiosis with Rhizobium bacteria. Additionally, like most vascular flowering plants, legumes are able to form a mutualistic endosymbiosis with arbuscular mycorrhizal (AM) fungi. These beneficial associations can enhance the plant resistance to biotic and abiotic stresses. Understanding how symbiotic interactions influence and increase plant stress tolerance are relevant questions toward maintaining crop yield and food safety in the scope of climate change. Proteomics offers numerous tools for the identification of proteins involved in such responses, allowing the study of sub-cellular localization and turnover regulation, as well as the discovery of post-translational modifications (PTMs). The current work reviews the progress made during the last decades in the field of proteomics applied to the study of the legume-Rhizobium and -AM symbioses, and highlights their influence on the plant responses to pathogens and abiotic stresses. We further discuss future perspectives and new experimental approaches that are likely to have a significant impact on the field including peptidomics, mass spectrometric imaging, and quantitative proteomics. PMID:28769967

Breeding for cuticle-associated traits in crop species: traits, targets, and strategies.

PubMed

Petit, Johann; Bres, Cécile; Mauxion, Jean-Philippe; Bakan, Bénédicte; Rothan, Christophe

2017-11-09

Improving crop productivity and quality while promoting sustainable agriculture have become major goals in plant breeding. The cuticle is a natural film covering the aerial organs of plants and consists of lipid polyesters covered and embedded with wax. The cuticle protects plants against water loss and pathogens and affects traits with strong impacts on crop quality such as, for horticultural crops, fruit brightness, cracking, russeting, netting, and shelf life. Here we provide an overview of the most important cuticle-associated traits that can be targeted for crop improvement. To date, most studies on cuticle-associated traits aimed at crop breeding have been done on fleshy fruits. Less information is available for staple crops such as rice, wheat or maize. Here we present new insights into cuticle formation and properties resulting from the study of genetic resources available for the various crop species. Our review also covers the current strategies and tools aimed at exploiting available natural and artificially induced genetic diversity and the technologies used to transfer the beneficial alleles affecting cuticle-associated traits to commercial varieties. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Biotech crop planting resumes high adoption in 2016.

PubMed

Aldemita, Rhodora R; Hautea, Randy A

2018-01-02

The global area of biotech crops in 2016 increased from 179.7 million hectares to 185.1 million hectares, a 3% increase equivalent to 5.4 million hectares. Some 26 countries planted biotech crops, 19 of which were developing countries and seven were industrial. Information and data collected from various credible sources showed variations from the previous year. Fluctuations in biotech crop area (both increases and decreases) are influenced by factors including, among others, acceptance and commercialization of new products, demand for meat and livestock feeds, weather conditions, global market price, disease/pest pressure, and government's enabling policies. Countries which have increased biotech crop area in decreasing order in 2016 were Brazil, United States of America, Canada, South Africa, Australia, Bolivia, Philippines, Spain, Vietnam, Bangladesh, Colombia, Honduras, Chile, Sudan, Slovakia, and Costa Rica. Countries with decreased biotech area in decreasing order were China, India, Argentina, Paraguay, Uruguay, Mexico, Portugal, and Czech Republic, in decreasing incremental decrease in biotech area. Pakistan and Myanmar were the only countries with no change in biotech crop (cotton) planted. Information detailed in the paper including future crops and traits in each country could guide stakeholders in informed crafting of strategies and policies for increased adoption of biotech crops in the country.

Effects of Cover Crops to Offset Soil Carbon Changes Under No-till on an Ohio farm when Biomass is Harvested

NASA Astrophysics Data System (ADS)

Kimble, J. M.; Everett, L. R.; Richards, W.

2003-12-01

The results of a long term experiment to look at the use of cover crops and there effect on soil organic carbon. No-till has been shown to increase SOC and improve the overall soil quality under conditions where the biomass has been returned to the field. However, biomass may be removed as silage or for use in biofuels. The removal will reduce the inputs to the field so to overcome the amount of biomass not returned to the soil different cover crops were used. This experiment was done on a working farm where the corn biomass was being removed as silage. Four cover crops were planted in early September of 2002: rye, oats, clover, and canola with two controls, one with no cover crop and one where corn stubble was left on the field. The soils were sampled soon after the crops were planted and again in the spring of 2003 before the cover crops were killed just prior to planting. The first results indicate that the most root biomass was produced by the rye followed by oats then canola and then clover.

Surveying Rubisco Diversity and Temperature Response to Improve Crop Photosynthetic Efficiency.

PubMed

Orr, Douglas J; Alcântara, André; Kapralov, Maxim V; Andralojc, P John; Carmo-Silva, Elizabete; Parry, Martin A J

2016-10-01

The threat to global food security of stagnating yields and population growth makes increasing crop productivity a critical goal over the coming decades. One key target for improving crop productivity and yields is increasing the efficiency of photosynthesis. Central to photosynthesis is Rubisco, which is a critical but often rate-limiting component. Here, we present full Rubisco catalytic properties measured at three temperatures for 75 plants species representing both crops and undomesticated plants from diverse climates. Some newly characterized Rubiscos were naturally "better" compared to crop enzymes and have the potential to improve crop photosynthetic efficiency. The temperature response of the various catalytic parameters was largely consistent across the diverse range of species, though absolute values showed significant variation in Rubisco catalysis, even between closely related species. An analysis of residue differences among the species characterized identified a number of candidate amino acid substitutions that will aid in advancing engineering of improved Rubisco in crop systems. This study provides new insights on the range of Rubisco catalysis and temperature response present in nature, and provides new information to include in models from leaf to canopy and ecosystem scale. © 2016 American Society of Plant Biologists. All Rights Reserved.

Development of transgenic crops based on photo-biotechnology.

PubMed

Ganesan, Markkandan; Lee, Hyo-Yeon; Kim, Jeong-Il; Song, Pill-Soon

2017-11-01

The phenotypes associated with plant photomorphogenesis such as the suppressed shade avoidance response and de-etiolation offer the potential for significant enhancement of crop yields. Of many light signal transducers and transcription factors involved in the photomorphogenic responses of plants, this review focuses on the transgenic overexpression of the photoreceptor genes at the uppermost stream of the signalling events, particularly phytochromes, crytochromes and phototropins as the transgenes for the genetic engineering of crops with improved harvest yields. In promoting the harvest yields of crops, the photoreceptors mediate the light regulation of photosynthetically important genes, and the improved yields often come with the tolerance to abiotic stresses such as drought, salinity and heavy metal ions. As a genetic engineering approach, the term photo-biotechnology has been coined to convey the idea that the greater the photosynthetic efficiency that crop plants can be engineered to possess, the stronger the resistance to biotic and abiotic stresses. Development of GM crops based on photoreceptor transgenes (mainly phytochromes, crytochromes and phototropins) is reviewed with the proposal of photo-biotechnology that the photoreceptors mediate the light regulation of photosynthetically important genes, and the improved yields often come with the added benefits of crops' tolerance to environmental stresses. © 2016 John Wiley & Sons Ltd.

Quantifying the efficiency of photoprotection

PubMed Central

2017-01-01

A novel emerging technology for the assessment of the photoprotective ‘power’ of non-photochemical fluorescence quenching (NPQ) has been reviewed and its insightful outcomes are explained using several examples. The principles of the method are described in detail as well as the work undertaken for its justification. This pulse amplitude modulated chlorophyll fluorescence approach has been applied for the past 5 years to quantify the photoprotective effectiveness of the NPQ and the light tolerance in Arabidopsis plants grown under various light conditions, during ontogenetic development as well as in a range of mutants impaired in carotenoid and protein biosynthesis. The future applications of this approach for the assessment of crop plant light tolerance are outlined. The perspective of obtaining detailed information about how the extent of photoinhibition and photoprotection can affect plant development, growth and productivity is highlighted, including the potential for us to predict the influence of environmental elements on plant performance and yield of crops. The novel methodology can be used to build up comprehensive light tolerance databases for various current and emerging varieties of crops that are grown outdoors as well as in artificial light environments, in order to optimize for the best environmental conditions that enable high crop productivity. This article is part of the themed issue ‘Enhancing photosynthesis in crop plants: targets for improvement’. PMID:28808106

Plant tolerance to high temperature in a changing environment: scientific fundamentals and production of heat stress-tolerant crops

PubMed Central

Bita, Craita E.; Gerats, Tom

2013-01-01

Global warming is predicted to have a general negative effect on plant growth due to the damaging effect of high temperatures on plant development. The increasing threat of climatological extremes including very high temperatures might lead to catastrophic loss of crop productivity and result in wide spread famine. In this review, we assess the impact of global climate change on the agricultural crop production. There is a differential effect of climate change both in terms of geographic location and the crops that will likely show the most extreme reductions in yield as a result of expected extreme fluctuations in temperature and global warming in general. High temperature stress has a wide range of effects on plants in terms of physiology, biochemistry and gene regulation pathways. However, strategies exist to crop improvement for heat stress tolerance. In this review, we present recent advances of research on all these levels of investigation and focus on potential leads that may help to understand more fully the mechanisms that make plants tolerant or susceptible to heat stress. Finally, we review possible procedures and methods which could lead to the generation of new varieties with sustainable yield production, in a world likely to be challenged both by increasing population, higher average temperatures and larger temperature fluctuations. PMID:23914193

Photo-biotechnology as a tool to improve agronomic traits in crops.

PubMed

Gururani, Mayank Anand; Ganesan, Markkandan; Song, Pill-Soon

2015-01-01

Phytochromes are photosensory phosphoproteins with crucial roles in plant developmental responses to light. Functional studies of individual phytochromes have revealed their distinct roles in the plant's life cycle. Given the importance of phytochromes in key plant developmental processes, genetically manipulating phytochrome expression offers a promising approach to crop improvement. Photo-biotechnology refers to the transgenic expression of phytochrome transgenes or variants of such transgenes. Several studies have indicated that crop cultivars can be improved by modulating the expression of phytochrome genes. The improved traits include enhanced yield, improved grass quality, shade-tolerance, and stress resistance. In this review, we discuss the transgenic expression of phytochrome A and its hyperactive mutant (Ser599Ala-PhyA) in selected crops, such as Zoysia japonica (Japanese lawn grass), Agrostis stolonifera (creeping bentgrass), Oryza sativa (rice), Solanum tuberosum (potato), and Ipomea batatas (sweet potato). The transgenic expression of PhyA and its mutant in various plant species imparts biotechnologically useful traits. Here, we highlight recent advances in the field of photo-biotechnology and review the results of studies in which phytochromes or variants of phytochromes were transgenically expressed in various plant species. We conclude that photo-biotechnology offers an excellent platform for developing crops with improved properties. Copyright © 2014 Elsevier Inc. All rights reserved.

Uptake of {sup 137}Cs in vegetable crops grown on a contaminated lakebed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seel, J.F.; Adriano, D.C.; Whicker, F.W.

1995-06-01

Mean concentration and plant:soil concentration ratios of {sup 137}Cs were determined for six vegetable crops grown on an exposed, contaminated lakebed of a former reactor cooling reservoir in South Carolina. Each crop species was grown with or without potassium fertilizer. Selected crops were also irrigated with either reservoir water or groundwater. Subsamples of crops were prepared for human consumption before analysis to determine the extent of any loss. Plant:soil concentration ratios (dry basis) ranged from 0.22 to 6.82, values which were substantially higher than those used in generic assessment models. While there was no statistically significant effect of irrigation sourcemore » or culinary preparation, the effect of potassium-fertilizer was dramatic. In many cases, concentrations of {sup 137}Cs in those plants receiving potassium were less than half of the concentrations in plants that did not receive potassium. Significant differences among species and {sup 131}Cs plant parts for concentrations were observed. Dose/risk calculations for the ingestion of these vegetables by a hypothetical 30-y resident indicates the possibility of a lifetime fatal cancer risk well-above the U.S. Environmental Protection Agency`s regulatory guideline of 10{sup -4}. 33 refs., 4 figs., 2 tabs.« less

Plant tolerance to high temperature in a changing environment: scientific fundamentals and production of heat stress-tolerant crops.

PubMed

Bita, Craita E; Gerats, Tom

2013-01-01

Global warming is predicted to have a general negative effect on plant growth due to the damaging effect of high temperatures on plant development. The increasing threat of climatological extremes including very high temperatures might lead to catastrophic loss of crop productivity and result in wide spread famine. In this review, we assess the impact of global climate change on the agricultural crop production. There is a differential effect of climate change both in terms of geographic location and the crops that will likely show the most extreme reductions in yield as a result of expected extreme fluctuations in temperature and global warming in general. High temperature stress has a wide range of effects on plants in terms of physiology, biochemistry and gene regulation pathways. However, strategies exist to crop improvement for heat stress tolerance. In this review, we present recent advances of research on all these levels of investigation and focus on potential leads that may help to understand more fully the mechanisms that make plants tolerant or susceptible to heat stress. Finally, we review possible procedures and methods which could lead to the generation of new varieties with sustainable yield production, in a world likely to be challenged both by increasing population, higher average temperatures and larger temperature fluctuations.

Assessment of Climate Change Impacts on Agricultural Water Demands and Crop Yields in California's Central Valley

NASA Astrophysics Data System (ADS)

Tansey, M. K.; Flores-Lopez, F.; Young, C. A.; Huntington, J. L.

2012-12-01

Long term planning for the management of California's water resources requires assessment of the effects of future climate changes on both water supply and demand. Considerable progress has been made on the evaluation of the effects of future climate changes on water supplies but less information is available with regard to water demands. Uncertainty in future climate projections increases the difficulty of assessing climate impacts and evaluating long range adaptation strategies. Compounding the uncertainty in the future climate projections is the fact that most readily available downscaled climate projections lack sufficient meteorological information to compute evapotranspiration (ET) by the widely accepted ASCE Penman-Monteith (PM) method. This study addresses potential changes in future Central Valley water demands and crop yields by examining the effects of climate change on soil evaporation, plant transpiration, growth and yield for major types of crops grown in the Central Valley of California. Five representative climate scenarios based on 112 bias corrected spatially downscaled CMIP 3 GCM climate simulations were developed using the hybrid delta ensemble method to span a wide range future climate uncertainty. Analysis of historical California Irrigation Management Information System meteorological data was combined with several meteorological estimation methods to compute future solar radiation, wind speed and dew point temperatures corresponding to the GCM projected temperatures and precipitation. Future atmospheric CO2 concentrations corresponding to the 5 representative climate projections were developed based on weighting IPCC SRES emissions scenarios. The Land, Atmosphere, and Water Simulator (LAWS) model was used to compute ET and yield changes in the early, middle and late 21st century for 24 representative agricultural crops grown in the Sacramento, San Joaquin and Tulare Lake basins. Study results indicate that changes in ET and yield vary between crops due to plant specific sensitivities to temperature, solar radiation and the vapor pressure deficits. Shifts in the growth period to earlier in the year, shortened growth period for annual crops as well as extended fall growth can also exert important influences. Projected increases in CO2 concentrations in the late 21st century exert very significant influences on ET and yield for many crops. To characterize potential impacts and the range of uncertainty, changes in total agricultural water demands and yields were computed assuming that current crop types and acreages in 21 Central Valley regional planning areas remained constant throughout the 21st century for each of the 5 representative future climate scenarios.

Genomics of crop wild relatives: expanding the gene pool for crop improvement.

PubMed

Brozynska, Marta; Furtado, Agnelo; Henry, Robert J

2016-04-01

Plant breeders require access to new genetic diversity to satisfy the demands of a growing human population for more food that can be produced in a variable or changing climate and to deliver the high-quality food with nutritional and health benefits demanded by consumers. The close relatives of domesticated plants, crop wild relatives (CWRs), represent a practical gene pool for use by plant breeders. Genomics of CWR generates data that support the use of CWR to expand the genetic diversity of crop plants. Advances in DNA sequencing technology are enabling the efficient sequencing of CWR and their increased use in crop improvement. As the sequencing of genomes of major crop species is completed, attention has shifted to analysis of the wider gene pool of major crops including CWR. A combination of de novo sequencing and resequencing is required to efficiently explore useful genetic variation in CWR. Analysis of the nuclear genome, transcriptome and maternal (chloroplast and mitochondrial) genome of CWR is facilitating their use in crop improvement. Genome analysis results in discovery of useful alleles in CWR and identification of regions of the genome in which diversity has been lost in domestication bottlenecks. Targeting of high priority CWR for sequencing will maximize the contribution of genome sequencing of CWR. Coordination of global efforts to apply genomics has the potential to accelerate access to and conservation of the biodiversity essential to the sustainability of agriculture and food production. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Crops nutrition management as measures for climate change adaptation

NASA Astrophysics Data System (ADS)

Hladkikh, Yevheniia

2017-04-01

The main feature of climate change in most countries worldwide is the increasing frequency of extreme weather events such as unpredictable floods, droughts and another abiotic stress for crops. It is not surprising that most countries are interested in technologies for adapting agriculture to climate change, and Ukraine is no exception. But traditional measures which exist in the world practice do not sufficiently take into account the importance of interactions between soil and plants. For example, from 138 projects of the European Climate Adaption Platform only 16 are correlated with the soil, but only one of them investigates the interaction in "soil-plant" system. In this connection, the main aim of our research was to determine the effectiveness of agrochemical techniques in plant nutrition management for crops adaptation to extreme weather fluctuations. The influence of different agrochemical measures in "soil-plant" system on the resilience of crops to different climate conditions of the growing season were investigated in a long-term field experiment that was started in 1969. The experiment was on a Chernozem at the Grakivske Experimental Station in Kharkiv region, Ukraine. Soil samples were taken during the growing season from field under different crops. Soil and plant samples analyses included macro- and micronutrients content, soil moisture. Research in the field experiment has demonstrated a close correlation between the average annual rainfall and content of available forms of macronutrients in the soil (especially for nitrate nitrogen the correlation coefficient was 0.98). Studies have shown that increasing the annual rainfall by 100 mm increases the content of nitrate nitrogen in the soil at 7 mg per kg. Another correlation has shown that the decrease amount of precipitation reduces the range of the N:P and consequently the availability of these elements to crops. Thus, in drought conditions, efficiency of the use of available nutrients by crops depends on the soil moisture and water use efficiency depends on the presence of the necessary nutrients for the crop. In our investigation, the following agrochemical crop nutrition management measures were used. Creating a high phosphate level of the soil contributes to the preservation of soil moisture reserves by 4% higher than in other agricultural background; optimizing the use of water by plants (the use of water per 1 ton of dry matter is reduced by 20-25%); improving the use of nitrogen from the soil to 18-30%. Implementation of integrated fertilizer system as an application macronutrients, micronutrients, biological preparations and humates in the critical phases of plant growth provides a 60% yield increase in extreme weather conditions. The formation of two strips of mineral fertilizers application at different depth contributes to improvement the use of nutrients by plants and to the increase of crop yields by 43% in drought conditions. Optimization of forms and kinds of fertilizer placement in the soil system and feeding time in the critical phases of plant growth, formation of agrochemical background significantly increase the stability of crop yields in different years by the hydrothermal conditions and increase their resistance to stress.

Plant immunity: unravelling the complexity of plant responses to biotic stresses.

PubMed

Miller, Robert Neil Gerard; Costa Alves, Gabriel Sergio; Van Sluys, Marie-Anne

2017-03-01

Plants are constantly exposed to evolving pathogens and pests, with crop losses representing a considerable threat to global food security. As pathogen evolution can overcome disease resistance that is conferred by individual plant resistance genes, an enhanced understanding of the plant immune system is necessary for the long-term development of effective disease management strategies. Current research is rapidly advancing our understanding of the plant innate immune system, with this multidisciplinary subject area reflected in the content of the 18 papers in this Special Issue. Advances in specific areas of plant innate immunity are highlighted in this issue, with focus on molecular interactions occurring between plant hosts and viruses, bacteria, phytoplasmas, oomycetes, fungi, nematodes and insect pests. We provide a focus on research across multiple areas related to pathogen sensing and plant immune response. Topics covered are categorized as follows: binding proteins in plant immunity; cytokinin phytohormones in plant growth and immunity; plant-virus interactions; plant-phytoplasma interactions; plant-fungus interactions; plant-nematode interactions; plant immunity in Citrus; plant peptides and volatiles; and assimilate dynamics in source/sink metabolism. Although knowledge of the plant immune system remains incomplete, the considerable ongoing scientific progress into pathogen sensing and plant immune response mechanisms suggests far reaching implications for the development of durable disease resistance against pathogens and pests. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Cisgenics - A Sustainable Approach for Crop Improvement

PubMed Central

Telem, R.S.; Wani, Shabir. H.; Singh, N.B.; Nandini, R.; Sadhukhan, R.; Bhattacharya, S.; Mandal, N.

2013-01-01

The implication of molecular biology in crop improvement is now more than three decades old. Not surprisingly, technology has moved on, and there are a number of new techniques that may or may not come under the genetically modified (GM) banner and, therefore, GM regulations. In cisgenic technology, cisgenes from crossable plants are used and it is a single procedure of gene introduction whereby the problem of linkage drag of other genes is overcome. The gene used in cisgenic approach is similar compared with classical breeding and cisgenic plant should be treated equally as classically bred plant and differently from transgenic plants. Therefore, it offers a sturdy reference to treat cisgenic plants similarly as classically bred plants, by exemption of cisgenesis from the current GMO legislations. This review covers the implications of cisgenesis towards the sustainable development in the genetic improvement of crops and considers the prospects for the technology. PMID:24396278

Systems biology approach in plant abiotic stresses.

PubMed

Mohanta, Tapan Kumar; Bashir, Tufail; Hashem, Abeer; Abd Allah, Elsayed Fathi

2017-12-01

Plant abiotic stresses are the major constraint on plant growth and development, causing enormous crop losses across the world. Plants have unique features to defend themselves against these challenging adverse stress conditions. They modulate their phenotypes upon changes in physiological, biochemical, molecular and genetic information, thus making them tolerant against abiotic stresses. It is of paramount importance to determine the stress-tolerant traits of a diverse range of genotypes of plant species and integrate those traits for crop improvement. Stress-tolerant traits can be identified by conducting genome-wide analysis of stress-tolerant genotypes through the highly advanced structural and functional genomics approach. Specifically, whole-genome sequencing, development of molecular markers, genome-wide association studies and comparative analysis of interaction networks between tolerant and susceptible crop varieties grown under stress conditions can greatly facilitate discovery of novel agronomic traits that protect plants against abiotic stresses. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

DNA damage and repair in plants – from models to crops

PubMed Central

Manova, Vasilissa; Gruszka, Damian

2015-01-01

The genomic integrity of every organism is constantly challenged by endogenous and exogenous DNA-damaging factors. Mutagenic agents cause reduced stability of plant genome and have a deleterious effect on development, and in the case of crop species lead to yield reduction. It is crucial for all organisms, including plants, to develop efficient mechanisms for maintenance of the genome integrity. DNA repair processes have been characterized in bacterial, fungal, and mammalian model systems. The description of these processes in plants, in contrast, was initiated relatively recently and has been focused largely on the model plant Arabidopsis thaliana. Consequently, our knowledge about DNA repair in plant genomes - particularly in the genomes of crop plants - is by far more limited. However, the relatively small size of the Arabidopsis genome, its rapid life cycle and availability of various transformation methods make this species an attractive model for the study of eukaryotic DNA repair mechanisms and mutagenesis. Moreover, abnormalities in DNA repair which proved to be lethal for animal models are tolerated in plant genomes, although sensitivity to DNA damaging agents is retained. Due to the high conservation of DNA repair processes and factors mediating them among eukaryotes, genes and proteins that have been identified in model species may serve to identify homologous sequences in other species, including crop plants, in which these mechanisms are poorly understood. Crop breeding programs have provided remarkable advances in food quality and yield over the last century. Although the human population is predicted to “peak” by 2050, further advances in yield will be required to feed this population. Breeding requires genetic diversity. The biological impact of any mutagenic agent used for the creation of genetic diversity depends on the chemical nature of the induced lesions and on the efficiency and accuracy of their repair. More recent targeted mutagenesis procedures also depend on host repair processes, with different pathways yielding different products. Enhanced understanding of DNA repair processes in plants will inform and accelerate the engineering of crop genomes via both traditional and targeted approaches. PMID:26557130

Biomass power for rural development. Technical progress report, October 1--December 31, 1997

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neuhauser, E.

The focus of the DOE/USDA sponsored biomass power for rural development project is to develop commercial energy crops for power generation by the year 2000. The New York based Salix Consortium project is a multi-partner endeavor, implemented in three stages. Phase-1, Final Design and Project Development, will conclude with the preparation of construction and/or operating permits, feedstock production plans, and contracts ready for signature. Field trials of willow (Salix) have been initiated at several locations in New York (Tully, Lockport, King Ferry, La Fayette, Massena, and Himrod) and co-firing tests are underway at Greenidge Station (NYSEG) and Dunkirk Station (NMPC).more » Phase-2 of the project will focus on scale-up of willow crop acreage, construction of co-firing facilities at Dunkirk Station (NMPC), and final modifications for Greenidge Station. Cofiring willow is also under consideration for GPU`s Seward Station where testing is underway. There will be an evaluation of the energy crop as part of the gasification trials occurring at BED`s McNeill Power Station. Phase-3 will represent fullscale commercialization of the energy crop and power generation on a sustainable basis. During the fourth quarter of 1997 the Consortium submitted a Phase-2 proposal. A few of the other more important milestones are outlined below. The first quarter of 1998 will be dominated by pre-planting activity in the spring.« less

Short Rotation Woody Crops Program. Quarterly progress report, March 1-May 31, 1985. [Sycamore, alders, black locust, larch, poplars, saltbush

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wright, L.L.; Perlack, R.D.; Wenzel, C.R.

1985-08-01

This report covers the progress of the Short Rotation Woody Crops Program (SRWCP) during the third quarter of fiscal year 1985. This report summarizes ORNL management activities, technical activities at ORNL and subcontract institutions, and the technology transfer that is occurring as a result of subcontractor and ORNL activities. Third-year results of a nutrient utilization study confirmed that there were no benefits to quarterly fertilization with urea nitrogen. Testing of one prototype short-rotation intensive culture harvester was conducted on a sycamore plantation on Scott Paper Company land in southern Alabama. Coppice yields of European black alder reported by Iowa Statemore » University indicate potential productivity of about 7.2 dry Mg . ha/sup -1/ . year/sup -1/ if the best trees are selected. Coppice yields were more than double first-rotation yields. About 31,000 black locust and larch trees were established in 12 genetic tests at 4 sites in Michigan. Seedling rotation productivity rates of 4-year-old hybrid poplar, based on harvest data, were reported by Pennsylvania State University. Rates varied from 4.8 dry Mg . ha/sup -1/ . year/sup -1/ to 10.7 dry Mg . ha/sup -1/ . year/sup -1/, depending on site, management strategy, and planting year. An efficient method for in vitro micropropagation of elite genotypes of fourwing saltbush was developed by Plant Resources Institute. A new study to evaluate yield/density relationships was established by the USDA Forest Service, Pacific Northwest Forest and Range Experiment Station. Dissertation research on the crown geometry of plantation-grown American sycamore was completed.« less

Spectral variations of canopy reflectance in support of precision agriculture

NASA Astrophysics Data System (ADS)

Kancheva, Rumiana; Georgiev, Georgi; Borisova, Denitsa; Nikolov, Hristo

2014-05-01

Agricultural monitoring is an important and continuously spreading activity in remote sensing and applied Earth observations. It supplies precise, reliable and valuable information on current crop condition and growth processes. In agriculture, the timing of seasonal cycles of crop activity is important for species classification and evaluation of crop development, growing conditions and potential yield. The correct interpretation of remotely sensed data, however, and the increasing demand for data reliability require ground-truth knowledge of the seasonal spectral behavior of different species and their relation to crop vigor. For this reason, we performed ground-based study of the seasonal response of winter wheat reflectance patterns to crop growth patterns. The goal was to quantify crop seasonality by establishing empirical relationships between plant biophysical and spectral properties in main ontogenetic periods. Phenology and agro-specific relationships allow assessing crop condition during different portions of the growth cycle and thus effectively tracking plant development, and finally make yield predictions. The applicability of a number of vegetation indices (VIs) for monitoring crop seasonal dynamics, its health condition, and yield potential was examined. Special emphasis we put on narrow-band indices as the availability of data from hyperspectral imagers is unavoidable future. The temporal behavior of vegetation indices revealed increased sensitivity to crop growth. The derived spectral-biophysical relationships allowed extraction of quantitative information about crop variables and yield at different stages of the phenological development. Relating plant spectral and biophysical variables in a phenology-based manner allows crop monitoring, that is crop diagnosis and predictions to be performed multiple times during plant ontogenesis. During active vegetative periods spectral data was highly indicative of plant growth trends and yield potential. The VIs values contributed to reliable yield prediction and showed very good correspondence with the estimates from biophysical models. For dates before full maturity most of the examined VIs proved to be meaningful statistical predictors of crop state-indicative biophysical variables. High correlations were obtained for canopy cover fraction, LAI, and biomass. Sensitivity to red, near-infrared and green reflectance showed both vigorous and stressed plants. As crops attained advanced growth stages, decreased sensitivity of VIs and weaker correlations with bioparameters were observed, yet still significant in a statistical sense. The results highlight the capability of the presented approach to track the dynamics of crop growth from multitemporal spectral data, and illustrate the prediction accuracy of the spectral models. The results are useful in assessing the efficiency of various spectral band ratios and other vegetation indices often used in remote sensing studies of natural and agricultural vegetation. They suggest that the used algorithm for data processing is particularly suitable for airborne cropland monitoring and could be expanded to sites at farm or municipality scale. The results reported are from pilot study carried out on a plot located in one of the established polygons for experimental crop monitoring. In the mentioned research GIS database is established for supporting the experiments and modelling process. Recommendations on good farming practices for medium sized farms for monitoring stress conditions such as drought and overfertilizing are developed.

Development of an agricultural biotechnology crop product: testing from discovery to commercialization.

PubMed

Privalle, Laura S; Chen, Jingwen; Clapper, Gina; Hunst, Penny; Spiegelhalter, Frank; Zhong, Cathy X

2012-10-17

"Genetically modified" (GM) or "biotech" crops have been the most rapidly adopted agricultural technology in recent years. The development of a GM crop encompasses trait identification, gene isolation, plant cell transformation, plant regeneration, efficacy evaluation, commercial event identification, safety evaluation, and finally commercial authorization. This is a lengthy, complex, and resource-intensive process. Crops produced through biotechnology are the most highly studied food or food component consumed. Before commercialization, these products are shown to be as safe as conventional crops with respect to feed, food, and the environment. This paper describes this global process and the various analytical tests that must accompany the product during the course of development, throughout its market life, and beyond.

Determining the potential productivity of food crops in controlled environments

NASA Technical Reports Server (NTRS)

Bugbee, Bruce

1992-01-01

The quest to determine the maximum potential productivity of food crops is greatly benefitted by crop growth models. Many models have been developed to analyze and predict crop growth in the field, but it is difficult to predict biological responses to stress conditions. Crop growth models for the optimal environments of a Controlled Environment Life Support System (CELSS) can be highly predictive. This paper discusses the application of a crop growth model to CELSS; the model is used to evaluate factors limiting growth. The model separately evaluates the following four physiological processes: absorption of PPF by photosynthetic tissue, carbon fixation (photosynthesis), carbon use (respiration), and carbon partitioning (harvest index). These constituent processes determine potentially achievable productivity. An analysis of each process suggests that low harvest index is the factor most limiting to yield. PPF absorption by plant canopies and respiration efficiency are also of major importance. Research concerning productivity in a CELSS should emphasize: (1) the development of gas exchange techniques to continuously monitor plant growth rates and (2) environmental techniques to reduce plant height in communities.

Envirotyping for deciphering environmental impacts on crop plants.

PubMed

Xu, Yunbi

2016-04-01

Global climate change imposes increasing impacts on our environments and crop production. To decipher environmental impacts on crop plants, the concept "envirotyping" is proposed, as a third "typing" technology, complementing with genotyping and phenotyping. Environmental factors can be collected through multiple environmental trials, geographic and soil information systems, measurement of soil and canopy properties, and evaluation of companion organisms. Envirotyping contributes to crop modeling and phenotype prediction through its functional components, including genotype-by-environment interaction (GEI), genes responsive to environmental signals, biotic and abiotic stresses, and integrative phenotyping. Envirotyping, driven by information and support systems, has a wide range of applications, including environmental characterization, GEI analysis, phenotype prediction, near-iso-environment construction, agronomic genomics, precision agriculture and breeding, and development of a four-dimensional profile of crop science involving genotype (G), phenotype (P), envirotype (E) and time (T) (developmental stage). In the future, envirotyping needs to zoom into specific experimental plots and individual plants, along with the development of high-throughput and precision envirotyping platforms, to integrate genotypic, phenotypic and envirotypic information for establishing a high-efficient precision breeding and sustainable crop production system based on deciphered environmental impacts.

Connecting Biochemical Photosynthesis Models with Crop Models to Support Crop Improvement

PubMed Central

Wu, Alex; Song, Youhong; van Oosterom, Erik J.; Hammer, Graeme L.

2016-01-01

The next advance in field crop productivity will likely need to come from improving crop use efficiency of resources (e.g., light, water, and nitrogen), aspects of which are closely linked with overall crop photosynthetic efficiency. Progress in genetic manipulation of photosynthesis is confounded by uncertainties of consequences at crop level because of difficulties connecting across scales. Crop growth and development simulation models that integrate across biological levels of organization and use a gene-to-phenotype modeling approach may present a way forward. There has been a long history of development of crop models capable of simulating dynamics of crop physiological attributes. Many crop models incorporate canopy photosynthesis (source) as a key driver for crop growth, while others derive crop growth from the balance between source- and sink-limitations. Modeling leaf photosynthesis has progressed from empirical modeling via light response curves to a more mechanistic basis, having clearer links to the underlying biochemical processes of photosynthesis. Cross-scale modeling that connects models at the biochemical and crop levels and utilizes developments in upscaling leaf-level models to canopy models has the potential to bridge the gap between photosynthetic manipulation at the biochemical level and its consequences on crop productivity. Here we review approaches to this emerging cross-scale modeling framework and reinforce the need for connections across levels of modeling. Further, we propose strategies for connecting biochemical models of photosynthesis into the cross-scale modeling framework to support crop improvement through photosynthetic manipulation. PMID:27790232

Connecting Biochemical Photosynthesis Models with Crop Models to Support Crop Improvement.

PubMed

Wu, Alex; Song, Youhong; van Oosterom, Erik J; Hammer, Graeme L

2016-01-01

The next advance in field crop productivity will likely need to come from improving crop use efficiency of resources (e.g., light, water, and nitrogen), aspects of which are closely linked with overall crop photosynthetic efficiency. Progress in genetic manipulation of photosynthesis is confounded by uncertainties of consequences at crop level because of difficulties connecting across scales. Crop growth and development simulation models that integrate across biological levels of organization and use a gene-to-phenotype modeling approach may present a way forward. There has been a long history of development of crop models capable of simulating dynamics of crop physiological attributes. Many crop models incorporate canopy photosynthesis (source) as a key driver for crop growth, while others derive crop growth from the balance between source- and sink-limitations. Modeling leaf photosynthesis has progressed from empirical modeling via light response curves to a more mechanistic basis, having clearer links to the underlying biochemical processes of photosynthesis. Cross-scale modeling that connects models at the biochemical and crop levels and utilizes developments in upscaling leaf-level models to canopy models has the potential to bridge the gap between photosynthetic manipulation at the biochemical level and its consequences on crop productivity. Here we review approaches to this emerging cross-scale modeling framework and reinforce the need for connections across levels of modeling. Further, we propose strategies for connecting biochemical models of photosynthesis into the cross-scale modeling framework to support crop improvement through photosynthetic manipulation.

Cover Crop Species and Management Influence Predatory Arthropods and Predation in an Organically Managed, Reduced-Tillage Cropping System.

PubMed

Rivers, Ariel N; Mullen, Christina A; Barbercheck, Mary E

2018-04-05

Agricultural practices affect arthropod communities and, therefore, have the potential to influence the activities of arthropods. We evaluated the effect of cover crop species and termination timing on the activity of ground-dwelling predatory arthropods in a corn-soybean-wheat rotation in transition to organic production in Pennsylvania, United States. We compared two cover crop treatments: 1) hairy vetch (Vicia villosa Roth) planted together with triticale (×Triticosecale Wittmack) after wheat harvest, and 2) cereal rye (Secale cereale Linnaeus) planted after corn harvest. We terminated the cover crops in the spring with a roller-crimper on three dates (early, middle, and late) based on cover crop phenology and standard practices for cash crop planting in our area. We characterized the ground-dwelling arthropod community using pitfall traps and assessed relative predation using sentinel assays with live greater waxworm larvae (Galleria mellonella Fabricius). The activity density of predatory arthropods was significantly higher in the hairy vetch and triticale treatments than in cereal rye treatments. Hairy vetch and triticale favored the predator groups Araneae, Opiliones, Staphylinidae, and Carabidae. Specific taxa were associated with cover crop condition (e.g., live or dead) and termination dates. Certain variables were positively or negatively associated with the relative predation on sentinel prey, depending on cover crop treatment and stage, including the presence of predatory arthropods and various habitat measurements. Our results suggest that management of a cover crop by roller-crimper at specific times in the growing season affects predator activity density and community composition. Terminating cover crops with a roller-crimper can conserve generalist predators.

Soil-plant water status and wine quality: the case study of Aglianico wine (the ZOViSA project)

NASA Astrophysics Data System (ADS)

Bonfante, Antonello; Manna, Piero; Albrizio, Rossella; Basile, Angelo; Agrillo, Antonietta; De Mascellis, Roberto; Caputo, Pellegrina; Delle Cave, Aniello; Gambuti, Angelita; Giorio, Pasquale; Guida, Gianpiero; Minieri, Luciana; Moio, Luigi; Orefice, Nadia; Terribile, Fabio

2014-05-01

The terroir analysis, aiming to achieve a better use of environmental features with respect to plant requirement and wine production, needs to be strongly rooted on hydropedology. In fact, the relations between wine quality and soil moisture regime during the cropping season is well established. The ZOViSA Project (Viticultural zoning at farm scale) tests a new physically oriented approach to terroir analysis based on the relations between the soil-plant water status and wine quality. The project is conducted in southern Italy in the farm Quintodecimo of Mirabella Eclano (AV) located in the Campania region, devoted to quality Aglianico red wine production (DOC). The soil spatial distribution of study area (about 3 ha) was recognized by classical soil survey and geophysics scan by EM38DD; then the soil-plant water status was monitored for three years in two experimental plots from two different soils (Cambisol and Calcisol). Daily climate variables (temperature, solar radiation, rainfall, wind), daily soil water variables (through TDR probes and tensiometers), crop development (biometric and physiological parameters), and grape must and wine quality were monitored. The agro-hydrological model SWAP was calibrated and applied in the two experimental plots to estimate soil-plant water status in different crop phenological stages. The effects of crop water status on crop response and wine quality was evaluated in two different pedo-systems, comparing the crop water stress index with both: crop physiological measurements (leaf gas exchange, leaf water potential, chlorophyll content, LAI measurement), grape bunches measurements (berry weight, sugar content, titratable acidity, etc.) and wine quality (aromatic response). Finally a "spatial application" of the model was carried out and different terroirs defined.

Effects of meteorological droughts on agricultural water resources in southern China

NASA Astrophysics Data System (ADS)

Lu, Houquan; Wu, Yihua; Li, Yijun; Liu, Yongqiang

2017-05-01

With the global warming, frequencies of drought are rising in the humid area of southern China. In this study, the effects of meteorological drought on the agricultural water resource based on the agricultural water resource carrying capacity (AWRCC) in southern China were investigated. The entire study area was divided into three regions based on the distributions of climate and agriculture. The concept of the maximum available water resources for crops was used to calculate AWRCC. Meanwhile, an agricultural drought intensity index (ADI), which was suitable for rice planting areas, was proposed based on the difference between crop water requirements and precipitation. The actual drought area and crop yield in drought years from 1961 to 2010 were analyzed. The results showed that ADI and AWRCC were significantly correlated with the actual drought occurrence area and food yield in the study area, which indicated ADI and AWRCC could be used in drought-related studies. The effects of seasonal droughts on AWRCC strongly depended on both the crop growth season and planting structure. The influence of meteorological drought on agricultural water resources was pronounced in regions with abundant water resources, especially in Southwest China, which was the most vulnerable to droughts. In Southwest China, which has dry and wet seasons, reducing the planting area of dry season crops and rice could improve AWRCC during drought years. Likewise, reducing the planting area of double-season rice could improve AWRCC during drought years in regions with a double-season rice cropping system. Our findings highlight the importance of adjusting the proportions of crop planting to improve the utilization efficiency of agricultural water resources and alleviate drought hazards in some humid areas.

Upper midwest climate variations: farmer responses to excess water risks.

PubMed

Morton, Lois Wright; Hobbs, Jonathan; Arbuckle, J Gordon; Loy, Adam

2015-05-01

Persistent above average precipitation and runoff and associated increased sediment transfers from cultivated ecosystems to rivers and oceans are due to changes in climate and human action. The US Upper Midwest has experienced a 37% increase in precipitation (1958-2012), leading to increased crop damage from excess water and off-farm loss of soil and nutrients. Farmer adaptive management responses to changing weather patterns have potential to reduce crop losses and address degrading soil and water resources. This research used farmer survey ( = 4778) and climate data (1971-2011) to model influences of geophysical context, past weather, on-farm flood and saturated soils experiences, and risk and vulnerability perceptions on management practices. Seasonal precipitation varied across six Upper Midwest subregions and was significantly associated with variations in management. Increased warm-season precipitation (2007-2011) relative to the past 40 yr was positively associated with no-till, drainage, and increased planting on highly erodible land (HEL). Experience with saturated soils was significantly associated with increased use of drainage and less use of no-till, cover crops, and planting on HEL. Farmers in counties with a higher percentage of soils considered marginal for row crops were more likely to use no-till, cover crops, and plant on HEL. Respondents who sell corn through multiple markets were more likely to have planted cover crops and planted on HEL in 2011.This suggests that regional climate conditions may not well represent individual farmers' actual and perceived experiences with changing climate conditions. Accurate climate information downscaled to localized conditions has potential to influence specific adaptation strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

A generic model to simulate air-borne diseases as a function of crop architecture.

PubMed

Casadebaig, Pierre; Quesnel, Gauthier; Langlais, Michel; Faivre, Robert

2012-01-01

In a context of pesticide use reduction, alternatives to chemical-based crop protection strategies are needed to control diseases. Crop and plant architectures can be viewed as levers to control disease outbreaks by affecting microclimate within the canopy or pathogen transmission between plants. Modeling and simulation is a key approach to help analyze the behaviour of such systems where direct observations are difficult and tedious. Modeling permits the joining of concepts from ecophysiology and epidemiology to define structures and functions generic enough to describe a wide range of epidemiological dynamics. Additionally, this conception should minimize computing time by both limiting the complexity and setting an efficient software implementation. In this paper, our aim was to present a model that suited these constraints so it could first be used as a research and teaching tool to promote discussions about epidemic management in cropping systems. The system was modelled as a combination of individual hosts (population of plants or organs) and infectious agents (pathogens) whose contacts are restricted through a network of connections. The system dynamics were described at an individual scale. Additional attention was given to the identification of generic properties of host-pathogen systems to widen the model's applicability domain. Two specific pathosystems with contrasted crop architectures were considered: ascochyta blight on pea (homogeneously layered canopy) and potato late blight (lattice of individualized plants). The model behavior was assessed by simulation and sensitivity analysis and these results were discussed against the model ability to discriminate between the defined types of epidemics. Crop traits related to disease avoidance resulting in a low exposure, a slow dispersal or a de-synchronization of plant and pathogen cycles were shown to strongly impact the disease severity at the crop scale.

Predawn respiration rates during flowering are highly predictive of yield response in Gossypium hirsutum when yield variability is water-induced.

PubMed

Snider, John L; Chastain, Daryl R; Meeks, Calvin D; Collins, Guy D; Sorensen, Ronald B; Byrd, Seth A; Perry, Calvin D

2015-07-01

Respiratory carbon evolution by leaves under abiotic stress is implicated as a major limitation to crop productivity; however, respiration rates of fully expanded leaves are positively associated with plant growth rates. Given the substantial sensitivity of plant growth to drought, it was hypothesized that predawn respiration rates (RPD) would be (1) more sensitive to drought than photosynthetic processes and (2) highly predictive of water-induced yield variability in Gossypium hirsutum. Two studies (at Tifton and Camilla Georgia) addressed these hypotheses. At Tifton, drought was imposed beginning at the onset of flowering (first flower) and continuing for three weeks (peak bloom) followed by a recovery period, and predawn water potential (ΨPD), RPD, net photosynthesis (AN) and maximum quantum yield of photosystem II (Fv/Fm) were measured throughout the study period. At Camilla, plants were exposed to five different irrigation regimes throughout the growing season, and average ΨPD and RPD were determined between first flower and peak bloom for all treatments. For both sites, fiber yield was assessed at crop maturity. The relationships between ΨPD, RPD and yield were assessed via non-linear regression. It was concluded for field-grown G. hirsutum that (1) RPD is exceptionally sensitive to progressive drought (more so than AN or Fv/Fm) and (2) average RPD from first flower to peak bloom is highly predictive of water-induced yield variability. Copyright © 2015 Elsevier GmbH. All rights reserved.

Cuphea: a new plant source of medium-chain fatty acids.

PubMed

Graham, S A

1989-01-01

The plant genus Cuphea (family Lythraceae) promises to provide a new source of industrially and nutritionally important medium-chain fatty acids, especially of lauric acid now supplied exclusively by coconut and palm kernel oils from foreign sources. The seed lipids of Cuphea were first discovered in the 1960s to contain high percentages of several medium-chain fatty acids, including caprylic, capric, lauric, and myristic acid. Research is still in the early stages, but it is intensifying toward the goal of developing the genus into a new temperate climate crop for production of specialty oils. Given the diversity of Cuphea seed lipid composition and the wide ecological and distributional range of the genus, it may be possible to tailor crops to produce selected fatty acids on demand under a variety of growing conditions. Cuphea comprises about 260 species, most native to the New World tropics. Its morphology, classification, chromosome numbers, distribution, ecology, and folk uses are presented. Seed structure is described and seed lipid composition for 73 species is summarized. Problems in domestication and agronomic progress are reviewed. Knowledge of the biosynthetic mechanism controlling the lipids produced by Cuphea remains very limited. Future research in this area, and particularly successful employment of gene transfer techniques, may allow genes controlling the mechanism to be transferred to an already established seed oil producer such as rapeseed. Presently, both traditional plant breeding techniques and newer biotechnological methods are directed toward Cuphea oilseed development.

Development of Farming Diversification with Implementation Plant Patterns as a Strategy of Economic Strengthening

NASA Astrophysics Data System (ADS)

Anwar, S.; Setyohadi, D. P. S.; Utami, M. M. D.; Damanhuri; Hariono, B.

2018-01-01

Bojonegoro, Tulungagung, and Ponorogo districts are an agrarian area and become one of the leading food crops producers in East Java Province. Diversification of farming in this region is done by applying season-based cropping pattern, which is cultivating various commodities in rotation. Farmers need diversification programs wetland cannot provide an optimal contribution to the income of farmers caused because farmers are not able to cultivate high value-added commodities due to limited capital. This research is to identify the characteristics of farming and to analyse the farming system to know the pattern of planting suggestion and prospect. The research used descriptive method, profit farming analysis, and SWOT. The results showed that each region has a specific planting pattern with rice as the main commodity grown in the rainy season followed by crops and horticultural crops and a suggested planting pattern that needs to be implemented by farmers to increase their income. The prospect of diversification of farming development through the implementation of the proposed planting pattern is very suitable with the character of the region and the market demand.

Microbial Community Dynamics and Response to Plant Growth-Promoting Microorganisms in the Rhizosphere of Four Common Food Crops Cultivated in Hydroponics.

PubMed

Sheridan, C; Depuydt, P; De Ro, M; Petit, C; Van Gysegem, E; Delaere, P; Dixon, M; Stasiak, M; Aciksöz, S B; Frossard, E; Paradiso, R; De Pascale, S; Ventorino, V; De Meyer, T; Sas, B; Geelen, D

2017-02-01

Plant growth promoting microorganisms (PGPMs) of the plant root zone microbiome have received limited attention in hydroponic cultivation systems. In the framework of a project aimed at the development of a biological life support system for manned missions in space, we investigated the effects of PGPMs on four common food crops (durum and bread wheat, potato and soybean) cultivated in recirculating hydroponic systems for a whole life cycle. Each crop was inoculated with a commercial PGPM mixture and the composition of the microbial communities associated with their root rhizosphere, rhizoplane/endosphere and with the recirculating nutrient solution was characterised through 16S- and ITS-targeted Illumina MiSeq sequencing. PGPM addition was shown to induce changes in the composition of these communities, though these changes varied both between crops and over time. Microbial communities of PGPM-treated plants were shown to be more stable over time. Though additional development is required, this study highlights the potential benefits that PGPMs may confer to plants grown in hydroponic systems, particularly when cultivated in extreme environments such as space.

Manipulation of plant architecture to enhance lignocellulosic biomass

PubMed Central

Stamm, Petra; Verma, Vivek; Ramamoorthy, Rengasamy; Kumar, Prakash P.

2012-01-01

Background Biofuels hold the promise to replace an appreciable proportion of fossil fuels. Not only do they emit significantly lower amounts of greenhouse gases, they are much closer to being ‘carbon neutral’, since the source plants utilize carbon dioxide for their growth. In particular, second-generation lignocellulosic biofuels from agricultural wastes and non-food crops such as switchgrass promise sustainability and avoid diverting food crops to fuel. Currently, available lignocellulosic biomass could yield sufficient bioethanol to replace ∼10 % of worldwide petroleum use. Increasing the biomass used for biofuel production and the yield of bioethanol will thus help meet global energy demands while significantly reducing greenhouse gas emissions. Scope We discuss the advantages of various biotechnological approaches to improve crops and highlight the contribution of genomics and functional genomics in this field. Current knowledge concerning plant hormones and their intermediates involved in the regulation of plant architecture is presented with a special focus on gibberellins and cytokinins, and their signalling intermediates. We highlight the potential of information gained from model plants such as Arabidopsis thaliana and rice (Oryza sativa) to accelerate improvement of fuel crops. PMID:23071897

Risk Management of GM Crops

EPA Science Inventory

Driven by biofuel demand, a significant increase in GM corn acreage is anticipated for the 2007 growing season with future planted GM corn acreage approaching 80% of the corn crop by 2009. As demand increases, grower non-compliance with mandated planting requirements is likely to...

Development of a multispectral sensor for crop canopy temperature measurement

USDA-ARS?s Scientific Manuscript database

Quantifying spatial and temporal variability in plant stress has precision agriculture applications in controlling variable rate irrigation and variable rate nutrient application. One approach to plant stress detection is crop canopy temperature measurement by the use of thermographic or radiometric...

IDENTIFICATION OF ESCAPED TRANSGENIC CREEPING BENTGRASS IN OREGON

EPA Science Inventory

When transgenic plants are cultivated near wild species that are sexually compatible with the crop, gene flow between the crop and wild plants is possible. A resultant concern is that transgene flow and transgene introgression within wild populations could have unintended ecologi...

Survey of Crop Losses in Response to Phytoparasitic Nematodes in the United States for 1994

PubMed Central

Koenning, S. R.; Overstreet, C.; Noling, J. W.; Donald, P. A.; Becker, J. O.; Fortnum, B. A.

1999-01-01

Previous reports of crop losses to plant-parasitic nematodes have relied on published results of survey data based on certain commodities, including tobacco, peanuts, cotton, and soybean. Reports on crop-loss assessment by land-grant universities and many commodity groups generally are no longer available, with the exception of the University of Georgia, the Beltwide Cotton Conference, and selected groups concerned with soybean. The Society of Nematologists Extension Committee contacted extension personnel in 49 U.S. states for information on estimated crop losses caused by plant-parasitic nematodes in major crops for the year 1994. Included in this paper are survey results from 35 states on various crops including corn, cotton, soybean, peanut, wheat, rice, sugarcane, sorghum, tobacco, numerous vegetable crops, fruit and nut crops, and golf greens. The data are reported systematically by state and include the estimated loss, hectarage of production, source of information, nematode species or taxon when available, and crop value. The major genera of phytoparasitic nematodes reported to cause crop losses were Heterodera, Hoplolaimus, Meloidogyne, Pratylenchus, Rotylenchulus, and Xiphinema. PMID:19270925

Survey of crop losses in response to phytoparasitic nematodes in the United States for 1994.

PubMed

Koenning, S R; Overstreet, C; Noling, J W; Donald, P A; Becker, J O; Fortnum, B A

1999-12-01

Previous reports of crop losses to plant-parasitic nematodes have relied on published results of survey data based on certain commodities, including tobacco, peanuts, cotton, and soybean. Reports on crop-loss assessment by land-grant universities and many commodity groups generally are no longer available, with the exception of the University of Georgia, the Beltwide Cotton Conference, and selected groups concerned with soybean. The Society of Nematologists Extension Committee contacted extension personnel in 49 U.S. states for information on estimated crop losses caused by plant-parasitic nematodes in major crops for the year 1994. Included in this paper are survey results from 35 states on various crops including corn, cotton, soybean, peanut, wheat, rice, sugarcane, sorghum, tobacco, numerous vegetable crops, fruit and nut crops, and golf greens. The data are reported systematically by state and include the estimated loss, hectarage of production, source of information, nematode species or taxon when available, and crop value. The major genera of phytoparasitic nematodes reported to cause crop losses were Heterodera, Hoplolaimus, Meloidogyne, Pratylenchus, Rotylenchulus, and Xiphinema.

Veggie: Space Vegetables for the International Space Station and Beyond

NASA Technical Reports Server (NTRS)

Massa, Gioia D.

2016-01-01

The Veggie vegetable production system was launched to the International Space Station (ISS) in 2014. Veggie was designed by ORBITEC to be a compact, low mass, low power vegetable production system for astronaut crews. Veggie consists of a light cap containing red, blue, and green LEDs, an extensible transparent bellows, and a baseplate with a root mat reservoir. Seeds are planted in plant pillows, small growing bags that interface with the reservoir. The Veggie technology validation test, VEG-01, was initiated with the first test crop of 'Outredgeous' red romaine lettuce. Prior to flight, lettuce seeds were sanitized and planted in a substrate of arcillite (baked ceramic) mixed with controlled release fertilizer. Upon initiation, astronauts open the packaged plant pillows, install them in the Veggie hardware, and prime the system with water. Operations include plant thinning, watering, and photography. Plants were grown on the ISS for 33 days, harvested, and returned frozen to Earth for analysis. Ground controls were conducted at Kennedy Space Center in controlled environment chambers reproducing ISS conditions of temperature, relative humidity, and CO2. Returned plant samples were analyzed for microbial food safety and chemistry including elements, antioxidants, anthocyanins and phenolics. In addition the entire plant microbiome was sequenced, and returned plant pillows were analyzed via x-ray tomography. Food safety analyses allowed us to gain approvals for future consumption of lettuce by the flight surgeons and the payload safety office. A second crop of lettuce was grown in 2015, and the crew consumed half the produce, with the remainder frozen for later analysis. This growth test was followed by testing of a new crop in Veggie, zinnias. Zinnias were grown to test a longer duration flowering crop in preparation for tests of tomatoes and other fruiting crops in the future. Zinnias were harvested in February. Samples from the second harvest of lettuce and the zinnia harvest are frozen on the ISS and will return with the next cargo return flight. Some challenges occurred in all tests, especially in the area of watering, with plants receiving insufficient or excess water leading to stressed growth. Zinnia plants were also challenged with fungal growth. Initial tests with Veggie have given us great insight into future crop production scenarios as we work to develop regular supplemental salad crop production on ISS and larger food production systems for our journey to Mars. Funding for this research comes from NASA's Space Biology Program.

Breeding crop plants with deep roots: their role in sustainable carbon, nutrient and water sequestration.

PubMed

Kell, Douglas B

2011-09-01

The soil represents a reservoir that contains at least twice as much carbon as does the atmosphere, yet (apart from 'root crops') mainly just the above-ground plant biomass is harvested in agriculture, and plant photosynthesis represents the effective origin of the overwhelming bulk of soil carbon. However, present estimates of the carbon sequestration potential of soils are based more on what is happening now than what might be changed by active agricultural intervention, and tend to concentrate only on the first metre of soil depth. Breeding crop plants with deeper and bushy root ecosystems could simultaneously improve both the soil structure and its steady-state carbon, water and nutrient retention, as well as sustainable plant yields. The carbon that can be sequestered in the steady state by increasing the rooting depths of crop plants and grasses from, say, 1 m to 2 m depends significantly on its lifetime(s) in different molecular forms in the soil, but calculations (http://dbkgroup.org/carbonsequestration/rootsystem.html) suggest that this breeding strategy could have a hugely beneficial effect in stabilizing atmospheric CO(2). This sets an important research agenda, and the breeding of plants with improved and deep rooting habits and architectures is a goal well worth pursuing.

Plant pathogen nanodiagnostic techniques: forthcoming changes?

PubMed Central

Khiyami, Mohammad A.; Almoammar, Hassan; Awad, Yasser M.; Alghuthaymi, Mousa A.; Abd-Elsalam, Kamel A.

2014-01-01

Plant diseases are among the major factors limiting crop productivity. A first step towards managing a plant disease under greenhouse and field conditions is to correctly identify the pathogen. Current technologies, such as quantitative polymerase chain reaction (Q-PCR), require a relatively large amount of target tissue and rely on multiple assays to accurately identify distinct plant pathogens. The common disadvantage of the traditional diagnostic methods is that they are time consuming and lack high sensitivity. Consequently, developing low-cost methods to improve the accuracy and rapidity of plant pathogens diagnosis is needed. Nanotechnology, nano particles and quantum dots (QDs) have emerged as essential tools for fast detection of a particular biological marker with extreme accuracy. Biosensor, QDs, nanostructured platforms, nanoimaging and nanopore DNA sequencing tools have the potential to raise sensitivity, specificity and speed of the pathogen detection, facilitate high-throughput analysis, and to be used for high-quality monitoring and crop protection. Furthermore, nanodiagnostic kit equipment can easily and quickly detect potential serious plant pathogens, allowing experts to help farmers in the prevention of epidemic diseases. The current review deals with the application of nanotechnology for quicker, more cost-effective and precise diagnostic procedures of plant diseases. Such an accurate technology may help to design a proper integrated disease management system which may modify crop environments to adversely affect crop pathogens. PMID:26740775

Companion Plants for Aphid Pest Management

PubMed Central

Ben-Issa, Refka; Gomez, Laurent; Gautier, Hélène

2017-01-01

A potential strategy for controlling pests is through the use of “companion plants” within a crop system. This strategy has been used in several trials to fight against a major crop insect pest: the aphid. We reviewed the literature to highlight the major mechanisms by which a companion plant may act. Trials carried out under laboratory or field conditions revealed that companion plants operate through several mechanisms. A companion plant may be associated with a target crop for various reasons. Firstly, it can attract aphids and draw them away from their host plants. Secondly, it can alter the recognition of the host plant. This effect is mostly attributed to companion plant volatiles since they disturb the aphid host plant location, and additionally they may react chemically and physiologically with the host plant, making it an unsuitable host for aphids. Thirdly, it can attract natural enemies by providing shelter and food resources. In this review, the feasibility of using companion plants is discussed. We conclude that many factors need to be taken into account for a successful companion plant strategy. For the best long-term results, companion plant strategies have to be combined with other alternative approaches against aphids. PMID:29053585

Dynamic chemical communication between plants and bacteria through airborne signals: induced resistance by bacterial volatiles.

PubMed

Farag, Mohamed A; Zhang, Huiming; Ryu, Choong-Min

2013-07-01

Certain plant growth-promoting rhizobacteria (PGPR) elicit induced systemic resistance (ISR) and plant growth promotion in the absence of physical contact with plants via volatile organic compound (VOC) emissions. In this article, we review the recent progess made by research into the interactions between PGPR VOCs and plants, focusing on VOC emission by PGPR strains in plants. Particular attention is given to the mechanisms by which these bacterial VOCs elicit ISR. We provide an overview of recent progress in the elucidation of PGPR VOC interactions from studies utilizing transcriptome, metabolome, and proteome analyses. By monitoring defense gene expression patterns, performing 2-dimensional electrophoresis, and studying defense signaling null mutants, salicylic acid and ethylene have been found to be key players in plant signaling pathways involved in the ISR response. Bacterial VOCs also confer induced systemic tolerance to abiotic stresses, such as drought and heavy metals. A review of current analytical approaches for PGPR volatile profiling is also provided with needed future developments emphasized. To assess potential utilization of PGPR VOCs for crop plants, volatile suspensions have been applied to pepper and cucumber roots and found to be effective at protecting plants against plant pathogens and insect pests in the field. Taken together, these studies provide further insight into the biological and ecological potential of PGPR VOCs for enhancing plant self-immunity and/or adaptation to biotic and abiotic stresses in modern agriculture.

Plant Uptake and Metabolism of Nitrofuran Antibiotics in Spring Onion Grown in Nitrofuran-Contaminated Soil.

PubMed

Wang, Yinan; Chan, K K Jason; Chan, Wan

2017-05-31

Environmental pollution caused by the discharge of mutagenic and carcinogenic nitrofurans to the aquatic and soil environment is an emerging public health concern because of the potential in producing drug-resistant microbes and being uptaken by food crops. Using liquid chromatography-tandem mass spectrometry analysis and with spring onion (Allium wakegi Araki) as the plant model, we investigated in this study the plant uptake and accumulation of nitrofuran from a contaminated environment. Our study revealed for the first time high uptake and accumulation rates of nitrofuran in the edible parts of the food crop. Furthermore, results indicated highly efficient plant metabolism of the absorbed nitrofuran within the plant, leading to the formation of genotoxic hydrazine-containing metabolites. The results from this study may disclose a previously unidentified human exposure pathway through contaminated food crops.

The Status of Fusarium Mycotoxins in Sub-Saharan Africa: A Review of Emerging Trends and Post-Harvest Mitigation Strategies towards Food Control.

PubMed

Chilaka, Cynthia Adaku; De Boevre, Marthe; Atanda, Olusegun Oladimeji; De Saeger, Sarah

2017-01-05

Fusarium fungi are common plant pathogens causing several plant diseases. The presence of these molds in plants exposes crops to toxic secondary metabolites called Fusarium mycotoxins. The most studied Fusarium mycotoxins include fumonisins, zearalenone, and trichothecenes. Studies have highlighted the economic impact of mycotoxins produced by Fusarium . These arrays of toxins have been implicated as the causal agents of wide varieties of toxic health effects in humans and animals ranging from acute to chronic. Global surveillance of Fusarium mycotoxins has recorded significant progress in its control; however, little attention has been paid to Fusarium mycotoxins in sub-Saharan Africa, thus translating to limited occurrence data. In addition, legislative regulation is virtually non-existent. The emergence of modified Fusarium mycotoxins, which may contribute to additional toxic effects, worsens an already precarious situation. This review highlights the status of Fusarium mycotoxins in sub-Saharan Africa, the possible food processing mitigation strategies, as well as future perspectives.

The Status of Fusarium Mycotoxins in Sub-Saharan Africa: A Review of Emerging Trends and Post-Harvest Mitigation Strategies towards Food Control

PubMed Central

Chilaka, Cynthia Adaku; De Boevre, Marthe; Atanda, Olusegun Oladimeji; De Saeger, Sarah

2017-01-01

Fusarium fungi are common plant pathogens causing several plant diseases. The presence of these molds in plants exposes crops to toxic secondary metabolites called Fusarium mycotoxins. The most studied Fusarium mycotoxins include fumonisins, zearalenone, and trichothecenes. Studies have highlighted the economic impact of mycotoxins produced by Fusarium. These arrays of toxins have been implicated as the causal agents of wide varieties of toxic health effects in humans and animals ranging from acute to chronic. Global surveillance of Fusarium mycotoxins has recorded significant progress in its control; however, little attention has been paid to Fusarium mycotoxins in sub-Saharan Africa, thus translating to limited occurrence data. In addition, legislative regulation is virtually non-existent. The emergence of modified Fusarium mycotoxins, which may contribute to additional toxic effects, worsens an already precarious situation. This review highlights the status of Fusarium mycotoxins in sub-Saharan Africa, the possible food processing mitigation strategies, as well as future perspectives. PMID:28067768

Evaluating the influence of plant-specific physiological parameterizations on the partitioning of land surface energy fluxes

NASA Astrophysics Data System (ADS)

Sulis, Mauro; Langensiepen, Matthias; Shrestha, Prabhakar; Schickling, Anke; Simmer, Clemens; Kollet, Stefan

2015-04-01

Vegetation has a significant influence on the partitioning of radiative forcing, the spatial and temporal variability of soil water and soil temperature. Therefore plant physiological properties play a key role in mediating and amplifying interactions and feedback mechanisms in the soil-vegetation-atmosphere continuum. Because of the direct impact on latent heat fluxes, these properties may also influence weather generating processes, such as the evolution of the atmospheric boundary layer (ABL). In land surface models, plant physiological properties are usually obtained from literature synthesis by unifying several plant/crop species in predefined vegetation classes. In this work, crop-specific physiological characteristics, retrieved from detailed field measurements, are included in the bio-physical parameterization of the Community Land Model (CLM), which is a component of the Terrestrial Systems Modeling Platform (TerrSysMP). The measured set of parameters for two typical European mid-latitudinal crops (sugar beet and winter wheat) is validated using eddy covariance measurements (sensible heat and latent heat) over multiple years from three measurement sites located in the North Rhine-Westphalia region, Germany. We found clear improvements of CLM simulations, when using the crop-specific physiological characteristics of the plants instead of the generic crop type when compared to the measurements. In particular, the increase of latent heat fluxes in conjunction with decreased sensible heat fluxes as simulated by the two new crop-specific parameter sets leads to an improved quantification of the diurnal energy partitioning. These findings are cross-validated using estimates of gross primary production extracted from net ecosystem exchange measurements. This independent analysis reveals that the better agreement between observed and simulated latent heat using the plant-specific physiological properties largely stems from an improved simulation of the photosynthesis process owing to a better estimation of the Rubisco enzyme kinematics. Finally, to evaluate the effects of the crop-specific parameterizations on the ABL dynamics, we perform a series of semi-idealized land-atmosphere coupled simulations by hypothesizing three cropland configurations. These numerical experiments reveal different heat and moisture budgets of the ABL that clearly impact the evolution of the boundary layer when using the crop-specific physiological properties.

Cultivation of high-biomass crops on coal mine spoil banks: can microbial inoculation compensate for high doses of organic matter?

PubMed

Gryndler, Milan; Sudová, Radka; Püschel, David; Rydlová, Jana; Janousková, Martina; Vosátka, Miroslav

2008-09-01

Two greenhouse experiments were focused on the application of arbuscular mycorrhizal fungi (AMF) and plant growth promoting rhizobacteria (PGPR) in planting of high-biomass crops on reclaimed spoil banks. In the first experiment, we tested the effects of different organic amendments on growth of alfalfa and on the introduced microorganisms. While growth of plants was supported in substrate with compost amendment, mycorrhizal colonization was suppressed. Lignocellulose papermill waste had no negative effects on AMF, but did not positively affect growth of plants. The mixture of these two amendments was found to be optimal in both respects, plant growth and mycorrhizal development. Decreasing doses of this mixture amendment were used in the second experiment, where the effects of microbial inoculation (assumed to compensate for reduced doses of organic matter) on growth of two high-biomass crops, hemp and reed canarygrass, were studied. Plant growth response to microbial inoculation was either positive or negative, depending on the dose of the applied amendment and plant species.

Biofuel crops with CAM photosynthesis: Economic potential on moisture-limited lands

NASA Astrophysics Data System (ADS)

Bartlett, Mark; Hartzell, Samantha; Porporato, Amilcare

2017-04-01

As the demand for food and renewable energy increases, the intelligent utilization of marginal lands is becoming increasingly critical. In marginal lands classified by limited rainfall or soil salinity, the cultivation of traditional C3 and C4 photosynthesis crops often is economically infeasible. However, in such lands, nontraditional crops with crassulacean acid metabolism (CAM) photosynthesis show great economic potential for cultivation. CAM crops including Opuntia (prickly pear) and Ananas (pineapple) achieve a water use efficiency which is three fold higher than C4 crops such as corn and 6-fold higher than C3 crops such as wheat, leading to a comparable annual productivity with only 20% of the water demand. This feature, combined with a shallow rooting depth and a high water storage capacity, allows CAM plants to take advantage of small, infrequent rainfall amounts in shallow, quickly draining soils. Furthermore, CAM plants typically have properties (e.g., high content of non-structural carbohydrates) that are favorable for biofuel production. Here, for marginal lands characterized by low soil moisture availability and/or high salinity, we assess the potential productivity and economic benefits of CAM plants. CAM productivity is estimated using a recently developed model which simulates CAM photosynthesis under a range of soil and climate conditions. From these results, we compare the energy and water resource inputs required by CAM plants to those required by more traditional C3 and C4 crops (corn, wheat, sorghum), and we evaluate the economic potential of CAM crops as sources of food, fodder, or biofuel in marginal soils. As precipitation events become more intense and infrequent, we show that even though marginal land area may increase, CAM crop cultivation shows great promise for maintaining high productivity with minimal water inputs. Our analysis indicates that on marginal lands, widespread cultivation of CAM crops as biofuel feedstock may help alleviate existing tensions between food and fuel production.

Recent Progress of Flower Colour Modification by Biotechnology

PubMed Central

Tanaka, Yoshikazu; Brugliera, Filippa; Chandler, Steve

2009-01-01

Genetically-modified, colour-altered varieties of the important cut-flower crop carnation have now been commercially available for nearly ten years. In this review we describe the manipulation of the anthocyanin biosynthesis pathway that has lead to the development of these varieties and how similar manipulations have been successfully applied to both pot plants and another cut-flower species, the rose. From this experience it is clear that down- and up-regulation of the flavonoid and anthocyanin pathway is both possible and predictable. The major commercial benefit of the application of this technology has so far been the development of novel flower colours through the development of transgenic varieties that produce, uniquely for the target species, anthocyanins derived from delphinidin. These anthocyanins are ubiquitous in nature, and occur in both ornamental plants and common food plants. Through the extensive regulatory approval processes that must occur for the commercialization of genetically modified organisms, we have accumulated considerable experimental and trial data to show the accumulation of delphinidin based anthocyanins in the transgenic plants poses no environmental or health risk. PMID:20054474

Effects of Planting Date, Small Grain Crop Destruction, Fallow, and Soil Temperature on the Management of Meloidogyne incognita

PubMed Central

Johnson, A. W.; Motsinger, R. E.

1990-01-01

The effects of planting date, rye (Secale cereale cv. Wren Abruzzi) and wheat (Triticura aestivum cv. Coker 797), crop destruction, fallow, and soil temperature on managing Meloidogyne incognita race 1 were determined in a 2-year study. More M. incognita juveniles (J2) and egg-producing adults were found in roots of rye planted 1 October than in roots of rye planted 1 November and wheat planted 1 November and 1 December. Numbers of M. incognita adults with and without egg masses were near or below detectable levels in roots of rye planted 1 November and wheat planted 1 November and 1 December. Meloidogyne incognita survived the mild winters in southern Georgia as J2 and eggs. The destruction of rye and wheat as a trap crop 1 March suppressed numbers of J2 in the soil temporarily but did not provide long-term benefits for susceptible crops that followed. In warmer areas where rye and wheat are grown in winter, reproduction of M. incognita may be avoided by delaying planting dates until soil temperature declines below the nematode penetration threshold (18 C), but no long-term benefits should be expected. The temperature threshold may be an important consideration in managing M. incognita population densities in areas having lower winter soil temperatures than southern Georgia. PMID:19287731

Metabolic engineering of plant-derived (E)-β-farnesene synthase genes for a novel type of aphid-resistant genetically modified crop plants.

PubMed

Yu, Xiu-Dao; Pickett, John; Ma, You-Zhi; Bruce, Toby; Napier, Johnathan; Jones, Huw D; Xia, Lan-Qin

2012-05-01

Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insecticides for long-term aphid control is undesirable because of the development of insecticide resistance, the potential negative effects on non-target organisms and environmental pollution. Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy. (E)-β-Farnesene (EβF) synthases catalyze the formation of EβF, which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species. EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds. Engineering of crop plants capable of synthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue, thus minimizing aphid infestation. In this review, the effects of aphids on host plants, plants' defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced. Furthermore, the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed. © 2012 Institute of Botany, Chinese Academy of Sciences.

SOIL ECOLOGY AS KEY TO SUSTAINABLE CROP PRODUCTION.

PubMed

De Deyn, G B

2015-01-01

Sustainable production of food, feed and fiberwarrants sustainable soil management and crop protection. The tools available to achieve this are both in the realm of the plants and of the soil, with a key role for plant-soil interactions. At the plant level we have vast knowledge of variation within plant species with respect to pests and diseases, based on which we can breed for resistance. However, given that systems evolve this resistance is bound to be temporarily, hence also other strategies are needed. Here I plea for an integrative approach for sustainable production using ecological principles. Ecology, the study of how organisms interact with their environment, teaches us that diversity promotes productivity and yield stability. These effects are thought to be governed through resource use complementarity and reduced build-up of pests and diseases both above- and belowground. In recent years especially the role of soil biotic interactions has revealed new insights in how plant diversity and productivity are related to soil biodiversity and the functions soil biota govern. In our grassland biodiversity studies we found that root feeders can promote plant diversity and succession without reducing plant community productivity, this illustrates the role of diversity to maintain productivity. Also diversity within species offers scope for sustainable production, for example through awareness of differences between plant genotypes in chemical defense compounds that can attract natural enemies of pests aboveground- and belowground thereby providing plant protection. Plant breeding can also benefit from using complementarity between plant species in the selection for new varieties, as our work demonstrated that when growing in species mixtures plant species adapt to each other over time such that their resource acquisition traits become more complementing. Finally, in a recent meta-analysis we show that earthworms can stimulate crop yield with on average 25%, but also that the effect size is conditional on fertilizer management and crop type. Together these examples illustrate the role of soil ecology in plant growth and the potential of its use for sustainable crop productivity through judicious management of plant-soil interactions.

Standardized plant disease evaluations will enhance resistance gene discovery

USDA-ARS?s Scientific Manuscript database

Gene discovery and marker development using DNA-based tools require plant populations with well documented phenotypes. If dissimilar phenotype evaluation methods or data scoring techniques are employed with different crops, or at different labs for the same crops, then data mining for genetic marker...

Field-based phenomics for plant genetics research

USDA-ARS?s Scientific Manuscript database

Perhaps the greatest challenge for crop research in the 21st century is how to predict crop performance as a function of genetic architecture and climate change. Advances in “next generation” DNA sequencing have greatly reduced genotyping costs. Methods for characterization of plant traits (phenotyp...

Identification of major genes affecting nutritional element concentrations in rice grains

USDA-ARS?s Scientific Manuscript database

Biofortification is the process by which the nutritional quality of food crops is improved through conventional plant breeding and/or use of biotechnology. Biofortification differs from conventional fortification in that biofortification aims to increase nutrient levels in crops during plant growth...

PLANT INCORPORATED PROTECTANT CROP MONITORING USING REMOTE SENSING

EPA Science Inventory

The extent of past and anticipated plantings of transgenic corn in the United States requires a new approach to monitor this important crop for the development of pest resistance. Remote sensing by aerial and/or satellite images may provide a method of identifying transgenic pest...

Double cropping opportunities for biomass crops in the North Central USA

USDA-ARS?s Scientific Manuscript database

Increased biomass crop production is essential for the development of sustainablae bioenergy and bio-product industries that will strengthen rural economies and increase employment in sectors ranging from farming to feedstock transportation to plant construction and operation. Double cropping, a far...

Usefulness of descriptors in phenotyping germplasm collections

USDA-ARS?s Scientific Manuscript database

A large number of crop germplasm collections are maintained within the U.S. National Plant Germplasm System (NPGS). For each of these crop collections, Crop Germplasm committees (CGC), crop curators, and collection staff have established extensive lists of descriptors or phenotypic traits by which t...

Spatio-temporal evaluation of plant height in corn via unmanned aerial systems

NASA Astrophysics Data System (ADS)

Varela, Sebastian; Assefa, Yared; Vara Prasad, P. V.; Peralta, Nahuel R.; Griffin, Terry W.; Sharda, Ajay; Ferguson, Allison; Ciampitti, Ignacio A.

2017-07-01

Detailed spatial and temporal data on plant growth are critical to guide crop management. Conventional methods to determine field plant traits are intensive, time-consuming, expensive, and limited to small areas. The objective of this study was to examine the integration of data collected via unmanned aerial systems (UAS) at critical corn (Zea mays L.) developmental stages for plant height and its relation to plant biomass. The main steps followed in this research were (1) workflow development for an ultrahigh resolution crop surface model (CSM) with the goal of determining plant height (CSM-estimated plant height) using data gathered from the UAS missions; (2) validation of CSM-estimated plant height with ground-truthing plant height (measured plant height); and (3) final estimation of plant biomass via integration of CSM-estimated plant height with ground-truthing stem diameter data. Results indicated a correlation between CSM-estimated plant height and ground-truthing plant height data at two weeks prior to flowering and at flowering stage, but high predictability at the later growth stage. Log-log analysis on the temporal data confirmed that these relationships are stable, presenting equal slopes for both crop stages evaluated. Concluding, data collected from low-altitude and with a low-cost sensor could be useful in estimating plant height.

Proximate composition of CELSS crops grown in NASA's Biomass Production Chamber.

PubMed

Wheeler, R M; Mackowiak, C L; Sager, J C; Knott, W M; Berry, W L

1996-01-01

Edible biomass from four crops of wheat (Triticum aestivum L.), four crops of lettuce (Lactuca sativa L.), four crops of potato (Solanum tuberosum L.), and three crops of soybean (Glycine max (L.) Merr.) grown in NASA's CELSS Biomass Production Chamber were analyzed for proximate composition. All plants were grown using recirculating nutrient (hydroponic) film culture with pH and electrical conductivity automatically controlled. Temperature and humidity were controlled to near optimal levels for each species and atmospheric carbon dioxide partial pressures were maintained near 100 Pa during the light cycles. Soybean seed contained the highest percentage of protein and fat, potato tubers and wheat seed contained the highest levels of carbohydrate, and lettuce leaves contained the highest level of ash. Analyses showed values close to data published for field-grown plants with several exceptions: In comparison with field-grown plants, wheat seed had higher protein levels; soybean seed had higher ash and crude fiber levels; and potato tubers and lettuce leaves had higher protein and ash levels. The higher ash and protein levels may have been a result of the continuous supply of nutrients (e.g., potassium and nitrogen) to the plants by the recirculating hydroponic culture.

Mining Halophytes for Plant Growth-Promoting Halotolerant Bacteria to Enhance the Salinity Tolerance of Non-halophytic Crops

PubMed Central

Etesami, Hassan; Beattie, Gwyn A.

2018-01-01

Salinity stress is one of the major abiotic stresses limiting crop production in arid and semi-arid regions. Interest is increasing in the application of PGPRs (plant growth promoting rhizobacteria) to ameliorate stresses such as salinity stress in crop production. The identification of salt-tolerant, or halophilic, PGPRs has the potential to promote saline soil-based agriculture. Halophytes are a useful reservoir of halotolerant bacteria with plant growth-promoting capabilities. Here, we review recent studies on the use of halophilic PGPRs to stimulate plant growth and increase the tolerance of non-halophytic crops to salinity. These studies illustrate that halophilic PGPRs from the rhizosphere of halophytic species can be effective bio-inoculants for promoting the production of non-halophytic species in saline soils. These studies support the viability of bioinoculation with halophilic PGPRs as a strategy for the sustainable enhancement of non-halophytic crop growth. The potential of this strategy is discussed within the context of ensuring sustainable food production for a world with an increasing population and continuing climate change. We also explore future research needs for using halotolerant PGPRs under salinity stress. PMID:29472908