Characterization of selenium-enriched wheat by agronomic biofortification.

PubMed

Galinha, Catarina; Sánchez-Martínez, María; Pacheco, Adriano M G; Freitas, Maria do Carmo; Coutinho, José; Maçãs, Benvindo; Almeida, Ana Sofia; Pérez-Corona, María Teresa; Madrid, Yolanda; Wolterbeek, Hubert T

2015-07-01

Agronomic biofortification of staple crops is an effective way to enhance their contents in essential nutrients up the food chain, with a view to correcting for their deficiencies in animal or human status. Selenium (Se) is one such case, for its uneven distribution in the continental crust and, therefore, in agricultural lands easily translates into substantial variation in nutritional intakes. Cereals are far from being the main sources of Se on a content basis, but they are likely the major contributors to intake on a dietary basis. To assess their potential to assimilate and biotransform Se, bread and durum wheat were enriched with Se through foliar and soil addition at an equivalent field rate of 100 g of Se per hectare (ha), using sodium selenate and sodium selenite as Se-supplementation matrices, in actual field conditions throughout. Biotransformation of inorganic Se was evaluated by using HPLC-ICP-MS after enzymatic hydrolysis for Se-species extraction in the resulting mature wheat grains. Selenomethionine and Se(VI) were identified and quantified: the former was the predominant species, representing 70-100 % of the total Se in samples; the maximum amount of inorganic Se was below 5 %. These results were similar for both supplementation methods and for both wheat varieties. Judging from the present results, one can conclude that agronomic biofortification of wheat may improve the nutritional quality of wheat grains with significant amounts of selenomethionine, which is an attractive option for increasing the Se status in human diets through Se-enriched, wheat-based foodstuff.

Influence of Agronomic and Climatic Factors on Fusarium Infestation and Mycotoxin Contamination of Cereals in Norway

PubMed Central

Bernhoft, A.; Torp, M.; Clasen, P.-E.; Løes, A.-K.; Kristoffersen, A.B.

2012-01-01

A total of 602 samples of organically and conventionally grown barley, oats and wheat was collected at grain harvest during 2002–2004 in Norway. Organic and conventional samples were comparable pairs regarding cereal species, growing site and harvest time, and were analysed for Fusarium mould and mycotoxins. Agronomic and climatic factors explained 10–30% of the variation in Fusarium species and mycotoxins. Significantly lower Fusarium infestation and concentrations of important mycotoxins were found in the organic cereals. The mycotoxins deoxynivalenol (DON) and HT-2 toxin (HT-2) constitute the main risk for human and animal health in Norwegian cereals. The impacts of various agronomic and climatic factors on DON and HT-2 as well as on their main producers F. graminearum and F. langsethiae and on total Fusarium were tested by multivariate statistics. Crop rotation with non-cereals was found to reduce all investigated characteristics significantly – mycotoxin concentrations as well as various Fusarium infestations. No use of mineral fertilisers and herbicides was also found to decrease F. graminearum, whereas lodged fields increased the occurrence of this species. No use of herbicides was also found to decrease F. langsethiae, but for this species the occurrence was lower in lodged fields. Total Fusarium infestation was decreased with no use of fungicides or mineral fertilisers, and with crop rotation, as well as by using herbicides and increased by lodged fields. Clay and to some extent silty soils seemed to reduce F. graminearum in comparison with sandy soils. Concerning climate factors, low temperature before grain harvest was found to increase DON; and high air humidity before harvest to increase HT-2. F. graminearum was negatively correlated with precipitation in July but correlated with air humidity before harvest. F. langsethiae was correlated with temperature in July. Total Fusarium increased with increasing precipitation in July. Organic cereal

Quantitative genetic analysis of agronomic and morphological traits in sorghum, Sorghum bicolor

PubMed Central

Mohammed, Riyazaddin; Are, Ashok K.; Bhavanasi, Ramaiah; Munghate, Rajendra S.; Kavi Kishor, Polavarapu B.; Sharma, Hari C.

2015-01-01

The productivity in sorghum is low, owing to various biotic and abiotic constraints. Combining insect resistance with desirable agronomic and morphological traits is important to increase sorghum productivity. Therefore, it is important to understand the variability for various agronomic traits, their heritabilities and nature of gene action to develop appropriate strategies for crop improvement. Therefore, a full diallel set of 10 parents and their 90 crosses including reciprocals were evaluated in replicated trials during the 2013–14 rainy and postrainy seasons. The crosses between the parents with early- and late-flowering flowered early, indicating dominance of earliness for anthesis in the test material used. Association between the shoot fly resistance, morphological, and agronomic traits suggested complex interactions between shoot fly resistance and morphological traits. Significance of the mean sum of squares for GCA (general combining ability) and SCA (specific combining ability) of all the studied traits suggested the importance of both additive and non-additive components in inheritance of these traits. The GCA/SCA, and the predictability ratios indicated predominance of additive gene effects for majority of the traits studied. High broad-sense and narrow-sense heritability estimates were observed for most of the morphological and agronomic traits. The significance of reciprocal combining ability effects for days to 50% flowering, plant height and 100 seed weight, suggested maternal effects for inheritance of these traits. Plant height and grain yield across seasons, days to 50% flowering, inflorescence exsertion, and panicle shape in the postrainy season showed greater specific combining ability variance, indicating the predominance of non-additive type of gene action/epistatic interactions in controlling the expression of these traits. Additive gene action in the rainy season, and dominance in the postrainy season for days to 50% flowering and plant

Genome sequencing and analysis of the whitefly (Bemisia tabaci) MEAM1, one of the most important vectors for plant viruses

USDA-ARS?s Scientific Manuscript database

Among whiteflies, the Bemisia tabaci (Hemiptera: Aleyrodidae) species complex is particularly important because of its ability to transmit hundreds of plant viruses, resulting in the loss of billions of U.S. dollars on agronomically important crops such as tomato, cucurbits, cassava, and cotton worl...

Waterfowl foraging in winter-flooded ricefields: Any agronomic benefits for farmers?

PubMed

Brogi, Anne; Pernollet, Claire A; Gauthier-Clerc, Michel; Guillemain, Matthieu

2015-12-01

Winter-flooding of ricefields provides foraging habitat to waterfowl, which in return may bring agronomic benefits to farmers. Our study experimentally tested the effect of mallards (Anas platyrhynchos) on the standing stalks and weed seed bank in the Camargue (France), both of which present major challenges for farmers. Three duck densities were tested: (D1) 5 ducks ha(-1) (historical nocturnal density), (D2) 23 ducks ha(-1) (present nocturnal density), and (D3) 300 ducks ha(-1) (Asian rice-duck farming density). The ducks reduced the stalks significantly: -27 % (D1), -52 % (D2), and -91 % (D3). Conversely, they decreased the number of seeds by only 3 % (D3) and the seed mass by about 21 % (D1 and D3), which was not significant. Besides they had no effect on seed species richness. This study clearly demonstrates that the winter-flooding effect on straw decomposition can be enhanced by waterfowl foraging, hence showing an agronomic benefit from ducks to farmers. However, there was no clear effect in terms of seed bank reduction.

Association Mapping Reveals Genetic Loci Associated with Important Agronomic Traits in Lentinula edodes, Shiitake Mushroom

PubMed Central

Li, Chuang; Gong, Wenbing; Zhang, Lin; Yang, Zhiquan; Nong, Wenyan; Bian, Yinbing; Kwan, Hoi-Shan; Cheung, Man-Kit; Xiao, Yang

2017-01-01

Association mapping is a robust approach for the detection of quantitative trait loci (QTLs). Here, by genotyping 297 genome-wide molecular markers of 89 Lentinula edodes cultivars in China, the genetic diversity, population structure and genetic loci associated with 11 agronomic traits were examined. A total of 873 alleles were detected in the tested strains with a mean of 2.939 alleles per locus, and the Shannon's information index was 0.734. Population structure analysis revealed two robustly differentiated groups among the Chinese L. edodes cultivars (FST = 0.247). Using the mixed linear model, a total of 43 markers were detected to be significantly associated with four traits. The number of markers associated with traits ranged from 9 to 26, and the phenotypic variations explained by each marker varied from 12.07% to 31.32%. Apart from five previously reported markers, the remaining 38 markers were newly reported here. Twenty-one markers were identified as simultaneously linked to two to four traits, and five markers were associated with the same traits in cultivation tests performed in two consecutive years. The 43 traits-associated markers were related to 97 genes, and 24 of them were related to 10 traits-associated markers detected in both years or identified previously, 13 of which had a >2-fold expression change between the mycelium and primordium stages. Our study has provided candidate markers for marker-assisted selection (MAS) and useful clues for understanding the genetic architecture of agronomic traits in the shiitake mushroom. PMID:28261189

Know your community - Biochar: agronomic and environmental uses community

USDA-ARS?s Scientific Manuscript database

The “Biochar: Agronomic and Environmental Uses” Community was formed in November 2010 (https://www.agronomy.org/membership/communities/biochar-agronomic-and-environmental-uses). The community’s initial function has been providing a forum at the tri-society’s national meetings to fill the need for a ...

Agronomic viability of New Zealand spinach and kale intercropping.

PubMed

Cecílio, Arthur B; Bianco, Matheus S; Tardivo, Caroline F; Pugina, Gabriel C M

2017-01-01

The intercropping is a production system that aims to provide increased yield with less environmental impact, due to greater efficiency in the use of natural resources and inputs involved in the production process. An experiment was carried out to evaluate the agronomic viability of kale and New Zealand spinach intercropping as a function of the spinach transplanting time. (0, 14, 28, 42, 56, 70, 84 and 98 days after transplanting of the kale). The total yield (TY) and yield per harvest (YH) of the kale in intercropping did not differ from those obtained in monoculture. The spinach TY was influenced by the transplanting time, the earlier the transplanting, the higher the TY. The spinach YH was not influenced by the transplanting time, but rather by the cultivation system. In intercropping, the spinach YH was 13.5% lower than in monoculture. The intercropping was agronomically feasible, since the land use efficiency index, which was not influenced by the transplanting time, had an average value of 1.71, indicating that the intercropping produced 71% more kale and spinach than the same area in monoculture. Competitiveness coefficient, aggressiveness and yield loss values showed that kale is the dominating species and spinach is the dominated.

Statistical analysis of agronomical factors and weather conditions influencing deoxynivalenol levels in oats in Scandinavia.

PubMed

Lindblad, M; Börjesson, T; Hietaniemi, V; Elen, O

2012-01-01

The relationship between weather data and agronomical factors and deoxynivalenol (DON) levels in oats was examined with the aim of developing a predictive model. Data were collected from a total of 674 fields during periods of up to 10 years in Finland, Norway and Sweden, and included DON levels in the harvested oats crop, agronomical factors and weather data. The results show that there was a large regional variation in DON levels, with higher levels in one region in Norway compared with other regions in Norway, Finland and Sweden. In this region the median DON level was 1000 ng g⁻¹ and the regulatory limit for human consumption (1750 ng g⁻¹) was exceeded in 28% of the samples. In other regions the median DON levels ranged from 75 to 270 ng g⁻¹, and DON levels exceeded 1750 ng g⁻¹ in 3-8% of the samples. Including more variables than region in a multiple regression model only increased the adjusted coefficient of determination from 0.17 to 0.24, indicating that very little of the variation in DON levels could be explained by weather data or agronomical factors. Thus, it was not possible to predict DON levels based on the variables included in this study. Further studies are needed to solve this problem. Apparently the infection and/or growth of DON producing Fusarium species are promoted in certain regions. One possibility may be to study the species distribution of fungal communities and their changes during the oats cultivation period in more detail.

Whole-genome resequencing of 292 pigeonpea accessions identifies genomic regions associated with domestication and agronomic traits.

PubMed

Varshney, Rajeev K; Saxena, Rachit K; Upadhyaya, Hari D; Khan, Aamir W; Yu, Yue; Kim, Changhoon; Rathore, Abhishek; Kim, Dongseon; Kim, Jihun; An, Shaun; Kumar, Vinay; Anuradha, Ghanta; Yamini, Kalinati Narasimhan; Zhang, Wei; Muniswamy, Sonnappa; Kim, Jong-So; Penmetsa, R Varma; von Wettberg, Eric; Datta, Swapan K

2017-07-01

Pigeonpea (Cajanus cajan), a tropical grain legume with low input requirements, is expected to continue to have an important role in supplying food and nutritional security in developing countries in Asia, Africa and the tropical Americas. From whole-genome resequencing of 292 Cajanus accessions encompassing breeding lines, landraces and wild species, we characterize genome-wide variation. On the basis of a scan for selective sweeps, we find several genomic regions that were likely targets of domestication and breeding. Using genome-wide association analysis, we identify associations between several candidate genes and agronomically important traits. Candidate genes for these traits in pigeonpea have sequence similarity to genes functionally characterized in other plants for flowering time control, seed development and pod dehiscence. Our findings will allow acceleration of genetic gains for key traits to improve yield and sustainability in pigeonpea.

The nuclear question: rethinking species importance in multi-species animal groups.

PubMed

Srinivasan, Umesh; Raza, Rashid Hasnain; Quader, Suhel

2010-09-01

1. Animals group for various benefits, and may form either simple single-species groups, or more complex multi-species associations. Multi-species groups are thought to provide anti-predator and foraging benefits to participant individuals. 2. Despite detailed studies on multi-species animal groups, the importance of species in group initiation and maintenance is still rated qualitatively as 'nuclear' (maintaining groups) or 'attendant' (species following nuclear species) based on species-specific traits. This overly simplifies and limits understanding of inherently complex associations, and is biologically unrealistic, because species roles in multi-species groups are: (i) likely to be context-specific and not simply a fixed species property, and (ii) much more variable than this dichotomy indicates. 3. We propose a new view of species importance (measured as number of inter-species associations), along a continuum from 'most nuclear' to 'least nuclear'. Using mixed-species bird flocks from a tropical rainforest in India as an example, we derive inter-species association measures from randomizations on bird species abundance data (which takes into account species 'availability') and data on 86 mixed-species flocks from two different flock types. Our results show that the number and average strength of inter-species associations covary positively, and we argue that species with many, strong associations are the most nuclear. 4. From our data, group size and foraging method are ecological and behavioural traits of species that best explain nuclearity in mixed-species bird flocks. Parallels have been observed in multi-species fish shoals, in which group size and foraging method, as well as diet, have been shown to correlate with nuclearity. Further, the context in which multi-species groups occur, in conjunction with species-specific traits, influences the role played by a species in a multi-species group, and this highlights the importance of extrinsic factors in

Brassicaceae Mustards: Traditional and Agronomic Uses in Australia and New Zealand.

PubMed

Rahman, Mahmudur; Khatun, Amina; Liu, Lei; Barkla, Bronwyn J

2018-01-21

Commonly cultivated Brassicaceae mustards, namely garlic mustard ( Alliaria petiolata ), white mustard ( Brassica alba ), Ethiopian mustard ( B. carinata ), Asian mustard ( B. juncea ), oilseed rape ( B. napus ), black mustard ( B. nigra ), rapeseed ( B. rapa ), white ball mustard ( Calepina irregularis ), ball mustard ( Neslia paniculata ), treacle mustard ( Erysimum repandum ), hedge mustard ( Sisymbrium officinale ), Asian hedge mustard ( S. orientale ), smooth mustard ( S. erysimoides ) and canola are the major economically important oilseed crops in many countries. Mustards were naturalized to Australia and New Zealand and Australia is currently the second largest exporter of Brassicaceae oilseeds to meet the global demand for a healthy plant-derived oil, high in polyunsaturated fats. Apart from providing edible oil, various parts of these plants and many of their phytochemicals have been used traditionally for both agronomic as well as medicinal purposes, with evidence of their use by early Australian and New Zealand settlers and also the indigenous population. This review provides an overview of the current knowledge of traditional and agronomic uses of Brassicaceae oilseeds and mustards with a focus on their importance in Australia and New Zealand.

Understanding Arsenic Dynamics in Agronomic Systems to ...

EPA Pesticide Factsheets

This review is on arsenic in agronomic systems, and covers processes that influence the entry of arsenic into the human food supply. The scope is from sources of arsenic (natural and anthropogenic) in soils, biogeochemical and rhizosphere processes that control arsenic speciation and availability, through to mechanisms of uptake by crop plants and potential mitigation strategies. This review makes a case for taking steps to prevent or limit crop uptake of arsenic, wherever possible, and to work toward a long-term solution to the presence of arsenic in agronomic systems. The past two decades have seen important advances in our understanding of how biogeochemical and physiological processes influence human exposure to soil arsenic, and thus must now prompt an informed reconsideration and unification of regulations to protect the quality of agricultural and residential soils. Consumption of staple foods such as rice, beverages such as apple juice, or vegetables grown in historically arsenic-contaminated soils is now recognized as a tangible route of arsenic exposure that, in many cases, is more significant than exposure from drinking water. Understanding the sources of arsenic to crop plants and the factors that influence them is key to reducing exposure now and preventing exposure in future. In addition to the abundant natural sources of arsenic, there are a large number of industrial and agricultural sources of arsenic to the soil; from mining wastes, coal fly

A computational interactome for prioritizing genes associated with complex agronomic traits in rice (Oryza sativa).

PubMed

Liu, Shiwei; Liu, Yihui; Zhao, Jiawei; Cai, Shitao; Qian, Hongmei; Zuo, Kaijing; Zhao, Lingxia; Zhang, Lida

2017-04-01

Rice (Oryza sativa) is one of the most important staple foods for more than half of the global population. Many rice traits are quantitative, complex and controlled by multiple interacting genes. Thus, a full understanding of genetic relationships will be critical to systematically identify genes controlling agronomic traits. We developed a genome-wide rice protein-protein interaction network (RicePPINet, http://netbio.sjtu.edu.cn/riceppinet) using machine learning with structural relationship and functional information. RicePPINet contained 708 819 predicted interactions for 16 895 non-transposable element related proteins. The power of the network for discovering novel protein interactions was demonstrated through comparison with other publicly available protein-protein interaction (PPI) prediction methods, and by experimentally determined PPI data sets. Furthermore, global analysis of domain-mediated interactions revealed RicePPINet accurately reflects PPIs at the domain level. Our studies showed the efficiency of the RicePPINet-based method in prioritizing candidate genes involved in complex agronomic traits, such as disease resistance and drought tolerance, was approximately 2-11 times better than random prediction. RicePPINet provides an expanded landscape of computational interactome for the genetic dissection of agronomically important traits in rice. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

The Importance of Species Traits for Species Distribution on Oceanic Islands

PubMed Central

Vazačová, Kristýna; Münzbergová, Zuzana

2014-01-01

Understanding species' ability to colonize new habitats is a key knowledge allowing us to predict species' survival in the changing landscapes. However, most studies exploring this topic observe distribution of species in landscapes which are under strong human influence being fragmented only recently and ignore the fact that the species distribution in these landscapes is far from equilibrium. Oceanic islands seem more appropriate systems for studying the relationship between species traits and its distribution as they are fragmented without human contribution and as they remained unchanged for a long evolutionary time. In our study we compared the values of dispersal as well as persistence traits among 18 species pairs from the Canary Islands differing in their distribution within the archipelago. The data were analyzed both with and without phylogenetic correction. The results demonstrate that no dispersal trait alone can explain the distribution of the species in the system. They, however, also suggest that species with better dispersal compared to their close relatives are better colonizers. Similarly, abundance of species in the archipelago seems to be an important predictor of species colonization ability only when comparing closely related species. This implies that analyses including phylogenetic correction may provide different insights than analyses without such a correction and both types of analyses should be combined to understand the importance of various plant traits for species colonization ability. PMID:25003737

Heavy Metal Uptake by C. esculentus, S. alterniflora and Agronomic Plants from Contaminated Soils and Sediments.

DTIC Science & Technology

1982-02-28

in March and potted in April. Seed sowing will ta..-e place in mid-May. The species sown will include a grass. wheat, lettuce and radish and C... effects varied. Soe started negativeLy, and became positive; others remained negative ( radish ), and others were positive aLl the time (wheat). ALL...agronomic plants selected were radish (Webb’s French Break- fast), lettuce (Paris White), wheat (spring), red fescue (Merlin) and ryegrass (S24). Each

LegumeDB1 bioinformatics resource: comparative genomic analysis and novel cross-genera marker identification in lupin and pasture legume species.

PubMed

Moolhuijzen, P; Cakir, M; Hunter, A; Schibeci, D; Macgregor, A; Smith, C; Francki, M; Jones, M G K; Appels, R; Bellgard, M

2006-06-01

The identification of markers in legume pasture crops, which can be associated with traits such as protein and lipid production, disease resistance, and reduced pod shattering, is generally accepted as an important strategy for improving the agronomic performance of these crops. It has been demonstrated that many quantitative trait loci (QTLs) identified in one species can be found in other plant species. Detailed legume comparative genomic analyses can characterize the genome organization between model legume species (e.g., Medicago truncatula, Lotus japonicus) and economically important crops such as soybean (Glycine max), pea (Pisum sativum), chickpea (Cicer arietinum), and lupin (Lupinus angustifolius), thereby identifying candidate gene markers that can be used to track QTLs in lupin and pasture legume breeding. LegumeDB is a Web-based bioinformatics resource for legume researchers. LegumeDB analysis of Medicago truncatula expressed sequence tags (ESTs) has identified novel simple sequence repeat (SSR) markers (16 tested), some of which have been putatively linked to symbiosome membrane proteins in root nodules and cell-wall proteins important in plant-pathogen defence mechanisms. These novel markers by preliminary PCR assays have been detected in Medicago truncatula and detected in at least one other legume species, Lotus japonicus, Glycine max, Cicer arietinum, and (or) Lupinus angustifolius (15/16 tested). Ongoing research has validated some of these markers to map them in a range of legume species that can then be used to compile composite genetic and physical maps. In this paper, we outline the features and capabilities of LegumeDB as an interactive application that provides legume genetic and physical comparative maps, and the efficient feature identification and annotation of the vast tracks of model legume sequences for convenient data integration and visualization. LegumeDB has been used to identify potential novel cross-genera polymorphic legume

Genome-wide sequence variations between wild and cultivated tomato species revisited by whole genome sequence mapping.

PubMed

Sahu, Kamlesh Kumar; Chattopadhyay, Debasis

2017-06-02

Cultivated tomato (Solanum lycopersicum L.) is the second most important vegetable crop after potato and a member of thirteen interfertile species of Solanum genus. Domestication and continuous selection for desirable traits made cultivated tomato species susceptible to many stresses as compared to the wild species. In this study, we analyzed and compared the genomes of wild and cultivated tomato accessions to identify the genomic regions that encountered changes during domestication. Analysis was based on SNP and InDel mining of twentynine accessions of twelve wild tomato species and forty accessions of cultivated tomato. Percentage of common SNPs among the accessions within a species corresponded with the reproductive behavior of the species. SNP profiles of the wild tomato species within a phylogenetic subsection varied with their geographical distribution. Interestingly, the ratio of genic SNP to total SNPs increased with phylogenetic distance of the wild tomato species from the domesticated species, suggesting that variations in gene-coding region play a major role in speciation. We retrieved 2439 physical positions in 1594 genes including 32 resistance related genes where all the wild accessions possessed a common wild variant allele different from all the cultivated accessions studied. Tajima's D analysis predicted a very strong purifying selection associated with domestication in nearly 1% of its genome, half of which is contributed by chromosome 11. This genomic region with a low Tajima's D value hosts a variety of genes associated with important agronomic trait such as, fruit size, tiller number and wax deposition. Our analysis revealed a broad-spectrum genetic base in wild tomato species and erosion of that in cultivated tomato due to recurrent selection for agronomically important traits. Identification of the common wild variant alleles and the genomic regions undergoing purifying selection during cultivation would facilitate future breeding program by

Descriptive statistics and correlation analysis of agronomic traits in a maize recombinant inbred line population.

PubMed

Zhang, H M; Hui, G Q; Luo, Q; Sun, Y; Liu, X H

2014-01-21

Maize (Zea mays L.) is one of the most important crops in the world. In this study, 13 agronomic traits of a recombinant inbred line population that was derived from the cross between Mo17 and Huangzao4 were investigated in maize: ear diameter, ear length, ear axis diameter, ear weight, plant height, ear height, days to pollen shed (DPS), days to silking (DS), the interval between DPS and DS, 100-kernel weight, kernel test weight, ear kernel weight, and kernel rate. Furthermore, the descriptive statistics and correlation analysis of the 13 traits were performed using the SPSS 11.5 software. The results providing the phenotypic data here are needed for the quantitative trait locus mapping of these agronomic traits.

Leptadenia reticulata (Retz.) Wight & Arn. (Jivanti): Botanical, Agronomical, Phytochemical, Pharmacological, and Biotechnological Aspects.

PubMed

Mohanty, Sudipta Kumar; Swamy, Mallappa Kumara; Sinniah, Uma Rani; Anuradha, Maniyam

2017-06-19

Leptadenia reticulata (Retz.) Wight & Arn. (Apocynaceae), is a traditional medicinal plant species widely used to treat various ailments such as tuberculosis, hematopoiesis, emaciation, cough, dyspnea, fever, burning sensation, night blindness, cancer, and dysentery. In Ayurveda, it is known for its revitalizing, rejuvenating, and lactogenic properties. This plant is one of the major ingredients in many commercial herbal formulations, including Speman, Envirocare, Calshakti, Antisept, and Chyawanprash. The therapeutic potential of this herb is because of the presence of diverse bioactive compounds such as α-amyrin, β-amyrin, ferulic acid, luteolin, diosmetin, rutin, β-sitosterol, stigmasterol, hentricontanol, a triterpene alcohol simiarenol, apigenin, reticulin, deniculatin, and leptaculatin. However, most biological studies on L. reticulata are restricted to crude extracts, and many biologically active compounds are yet to be identified in order to base the traditional uses of L. reticulata on evidence-based data. At present, L. reticulata is a threatened endangered plant because of overexploitation, unscientific harvesting, and habitat loss. The increased demand from pharmaceutical, nutraceutical, and veterinary industries has prompted its large-scale propagation. However, its commercial cultivation is hampered because of the non-availability of genuine planting material and the lack of knowledge about its agronomical practices. In this regard, micropropagation techniques will be useful to obtain true-to-type L. reticulata planting materials from an elite germplasm to meet the current demand. Adopting other biotechnological approaches such as synthetic seed technology, cryopreservation, cell culture, and genetic transformation can help conservation as well as increased metabolite production from L. reticulata. The present review summarizes scientific information on the botanical, agronomical, phytochemical, pharmacological, and biotechnological aspects of

The agronomic science of spatial and temporal water management:How much, when and where

USDA-ARS?s Scientific Manuscript database

The agronomic sciences are those that are applied to soil and water management and crop production, including soil, water and plant sciences and related disciplines. The science of spatial and temporal water management includes many agronomic science factors, including soil physics, biophysics, plan...

[Correlation analysis of major agronomic characters and the polysaccharide contents in Dendrobium officinale].

PubMed

Zhang, Lei; Zheng, Xi-Long; Qiu, Dao-Shou; Cai, Shi-Ke; Luo, Huan-Ming; Deng, Rui-Yun; Liu, Xiao-Jin

2013-10-01

In order to provide theoretical and technological basis for the germplasm innovation and variety breeding in Dendrobium officinale, a study of the correlation between polysaccharide content and agronomic characters was conducted. Based on the polysaccharide content determination and the agronomic characters investigation of 30 copies (110 individual plants) of Dendrobium officinale germplasm resources, the correlation between polysaccharide content and agronomic characters was analyzed via path and correlation analysis. Correlation analysis results showed that there was a significant negative correlation between average spacing and polysaccharide content, the correlation coefficient was -0.695. And the blade thickness was positively correlated with the polysaccharide content, but the correlation was not significant. The path analysis results showed that the stem length was the maximum influence factor to the polysaccharide, and it was positive effect, the direct path coefficient was 1.568. According to thess results, the polysaccharide content can be easily and intuitively estimated by the agronomic characters investigating data in the germpalsm resources screening and variety breeding. Therefore, it is a visual and practical technology guidance in quality variety breeding of Dendrobium officinale.

Development of Species-Specific Primers for Agronomical Thrips and Multiplex Assay for Quarantine Identification of Western Flower Thrips.

PubMed

Yeh, W B; Tseng, M J; Chang, N T; Wu, S Y; Tsai, Y S

2014-10-01

While morphological identification of thrips species has been difficult because of their minute size and a lack of easily recognizable characteristics, molecular identification based on the development of specific molecular markers can be easily and reliably carried out. Among the known molecular markers, the nuclear internal transcribed spacer (ITS) exhibits distinguishable variations among thrips species. In this study, sequences of ITS2 region of 10 agriculturally important thrips were established to design species-specific primers for polymerase chain reaction (PCR). ITS2 sequence variations within these species were far less than those among species, indicating the suitability of this marker for species-specific primers design. These primers, though with one or two sporadically variable positions, showed a good efficacy within species. The specificity of these primers, examined on thrips species belonging to 15 genera, proved satisfactory. Furthermore, a multiplex PCR was used successfully for identifying Frankliniella occidentalis (Pergande), an insect pest monitored for quarantine purpose, and three additional thrips also commonly found in imported agricultural products and field samples, i.e., Thrips tabaci Lindeman, Thrips hawaiiensis (Morgan), and Frankliniella intonsa (Trybom). This study has demonstrated that specific primers and multiplex PCR based on ITS2 are reliable, convenient, and diagnostic tool to discriminate thrips species of quarantine and agricultural importance. © 2014 Entomological Society of America.

Effect of agronomical practices on carpology, fruit and oil composition, and oil sensory properties, in olive (Olea europaea L.).

PubMed

Rosati, Adolfo; Cafiero, Caterina; Paoletti, Andrea; Alfei, Barbara; Caporali, Silvia; Casciani, Lorena; Valentini, Massimiliano

2014-09-15

We examined whether some agronomical practices (i.e. organic vs. conventional) affect olive fruit and oil composition, and oil sensory properties. Fruit characteristics (i.e. fresh and dry weight of pulp and pit, oil content on a fresh and dry weight basis) did not differ. Oil chemical traits did not differ except for increased content of polyphenols in the organic treatments, and some changes in the acidic composition. Sensory analysis revealed increased bitterness (both cultivars) and pungency (Frantoio) and decreased sweetness (Frantoio) in the organic treatment. Fruit metabolomic analysis with HRMAS-NMR indicated significant changes in some compounds including glycocholate, fatty acids, NADPH, NADP+, some amino acids, thymidine, trigonelline, nicotinic acid, 5,6-dihydrouracil, hesanal, cis-olefin, β-D-glucose, propanal and some unassigned species. The results suggest that agronomical practices may have effects on fruit composition that may be difficult to detect unless a broad-spectrum analysis is used. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Application of Soil-Agroclimatic Index for Assessing the Agronomic Potential of Arable Lands in the Forest-Steppe Zone of Russia

NASA Astrophysics Data System (ADS)

Bulgakov, D. S.; Rukhovich, D. I.; Shishkonakova, E. A.; Vil'chevskaya, E. V.

2018-04-01

An assessment of the agronomic potential of arable lands in the forest-steppe zone of Russia (by the example of separate soil-agronomic districts) on the basis of the soil-agroclimatic index developed under the supervision of I.I. Karmanov is considered. The agricultural areas (64) separated on the territory of Russia and characterizing soil-agroclimatic conditions for cultivation of major and accompanying crops are differentiated into soil-agronomic districts (SADs) with due account for the administrative division of the country. A large diversity of agroclimatic and agronomical conditions creates the prerequisites for the inclusion of administrative regions into different SADs. The SADs concept implies a detailed analysis of information on the soil properties, geomorphic conditions, and farming conditions. The agronomic potential for major crops in the key SADs in the forest-steppe zone of the East European Plain (Voronezh and Penza oblasts) is high, though it is 25-30% lower than that in the North Caucasus (for winter wheat, sugar beet, sunflower, and spring barley) and in Kaliningrad oblast (for oats). In Western Siberia (Tyumen, Omsk, and Novosibirsk oblasts) and Eastern Siberia (Krasnoyarsk region and Irkutsk oblast), the agronomic potential of spring crops (wheat, barley, and oats) is only utilized by 35-45% in comparison with their European analogues. In the Far East with its monsoon climate and soil conditions (meadow podbels, brown forest soils), the crops characteristic of the European forest-steppe (soybean, rice, sugar beet) and the Trans-Ural forest-steppe (spring wheat) are cultivated. Their biological potential is utilized by only 50-60% in comparison with the European analogues. The materials of this study give us information on the degree of correspondence between the soilagroclimatic potential of the territory and the biological potential of cultivated crops. This is important in the context of improving the natural-agricultural zoning of Russia

Applications and challenges of next-generation sequencing in Brassica species.

PubMed

Wei, Lijuan; Xiao, Meili; Hayward, Alice; Fu, Donghui

2013-12-01

Next-generation sequencing (NGS) produces numerous (often millions) short DNA sequence reads, typically varying between 25 and 400 bp in length, at a relatively low cost and in a short time. This revolutionary technology is being increasingly applied in whole-genome, transcriptome, epigenome and small RNA sequencing, molecular marker and gene discovery, comparative and evolutionary genomics, and association studies. The Brassica genus comprises some of the most agro-economically important crops, providing abundant vegetables, condiments, fodder, oil and medicinal products. Many Brassica species have undergone the process of polyploidization, which makes their genomes exceptionally complex and can create difficulties in genomics research. NGS injects new vigor into Brassica research, yet also faces specific challenges in the analysis of complex crop genomes and traits. In this article, we review the advantages and limitations of different NGS technologies and their applications and challenges, using Brassica as an advanced model system for agronomically important, polyploid crops. Specifically, we focus on the use of NGS for genome resequencing, transcriptome sequencing, development of single-nucleotide polymorphism markers, and identification of novel microRNAs and their targets. We present trends and advances in NGS technology in relation to Brassica crop improvement, with wide application for sophisticated genomics research into agronomically important polyploid crops.

Comparative Agronomic Performance and Reaction to Fusarium wilt of Lens culinaris × L. orientalis and L. culinaris × L. ervoides derivatives.

PubMed

Singh, Mohar; Rana, Jai C; Singh, Badal; Kumar, Sandeep; Saxena, Deep R; Saxena, Ashok; Rizvi, Aqeel H; Sarker, Ashutosh

2017-01-01

The development of transgressive phenotype in the segregating populations has been speculated to contribute to niche divergence of hybrid lineages, which occurs most frequently at larger genetic distances. Wild Lens species are considered to be more resistant against major biotic and abiotic stresses than that of the cultivated species. In the present study, we assessed the comparative agronomic performance of lentil ( Lens culinaris subsp. culinaris ) inter-sub-specific ( L. culinaris subsp. orientalis ) and interspecific ( L. ervoides ) derivatives, also discussed its probable basis of occurrence. The F 3 , F 4 , and F 5 inter sub-specific and interspecific populations of ILL8006 × ILWL62 and ILL10829 × ILWL30, respectively revealed a substantial range of variation for majority of agro-morphological traits as reflected by the range, mean and coefficient of variation. A high level of fruitful heterosis was also observed in F 3 and F 4 progeny for important traits of interest. Phenotypic coefficient of variation (PCV) was higher in magnitude than genotypic coefficient of variation (GCV) in all generations for several quantitative characters. The results showed high heritability estimates for majority of traits in conjunction with low to high genetic advance in F 3 and F 4 generations. Further, F 5 progeny of ILL10829 × ILWL30, manifested resistant disease reaction for fifteen recombinant inbred lines (RILs) against ( Fusarium oxysporum f. sp. lentis ( Vasd. Srin .) Gord.). The multilocation agronomic evaluation of both crosses showed better results for earliness, desirable seed yield and Fusarium wilt resistance under two agro-ecological regions of north-western India. These better performing recombinants of ILL8006 × ILWL62 and ILL10829 × ILWL30 can be advanced for further genetic improvement and developing high yielding disease resistant cultivars of lentil.

Comparative Agronomic Performance and Reaction to Fusarium wilt of Lens culinaris × L. orientalis and L. culinaris × L. ervoides derivatives

PubMed Central

Singh, Mohar; Rana, Jai C.; Singh, Badal; Kumar, Sandeep; Saxena, Deep R.; Saxena, Ashok; Rizvi, Aqeel H.; Sarker, Ashutosh

2017-01-01

The development of transgressive phenotype in the segregating populations has been speculated to contribute to niche divergence of hybrid lineages, which occurs most frequently at larger genetic distances. Wild Lens species are considered to be more resistant against major biotic and abiotic stresses than that of the cultivated species. In the present study, we assessed the comparative agronomic performance of lentil (Lens culinaris subsp. culinaris) inter-sub-specific (L. culinaris subsp. orientalis) and interspecific (L. ervoides) derivatives, also discussed its probable basis of occurrence. The F3, F4, and F5 inter sub-specific and interspecific populations of ILL8006 × ILWL62 and ILL10829 × ILWL30, respectively revealed a substantial range of variation for majority of agro-morphological traits as reflected by the range, mean and coefficient of variation. A high level of fruitful heterosis was also observed in F3 and F4 progeny for important traits of interest. Phenotypic coefficient of variation (PCV) was higher in magnitude than genotypic coefficient of variation (GCV) in all generations for several quantitative characters. The results showed high heritability estimates for majority of traits in conjunction with low to high genetic advance in F3 and F4 generations. Further, F5 progeny of ILL10829 × ILWL30, manifested resistant disease reaction for fifteen recombinant inbred lines (RILs) against (Fusarium oxysporum f. sp. lentis (Vasd. Srin.) Gord.). The multilocation agronomic evaluation of both crosses showed better results for earliness, desirable seed yield and Fusarium wilt resistance under two agro-ecological regions of north-western India. These better performing recombinants of ILL8006 × ILWL62 and ILL10829 × ILWL30 can be advanced for further genetic improvement and developing high yielding disease resistant cultivars of lentil. PMID:28751897

DNA Barcodes for Forensically Important Fly Species in Brazil.

PubMed

Koroiva, Ricardo; de Souza, Mirian S; Roque, Fabio de Oliveira; Pepinelli, Mateus

2018-04-07

Here, we analyze 248 DNA barcode sequences of 35 fly species of forensic importance in Brazil. DNA barcoding can be effectively used for specimen identification of these species, allowing the unambiguous identification of 31 species, an overall success rate of 88%. Our results show a high rate of success for molecular identification using DNA barcoding sequences and open new perspectives for immature species identification, a subject on which limited forensic investigations exist in Tropical regions. We also address the implications of building a robust forensic DNA barcode database. A geographic bias is recognized for the COI dataset available for forensically important fly species in Brazil, with concentration of sequences from specimens collected mainly in sites located in the Cerrado, Mata Atlântica, and Pampa biomes.

Integrating Agronomic Principles with Management Experience in Introductory Agronomy.

ERIC Educational Resources Information Center

Vorst, J. J.

1989-01-01

Explains the use of a cropping systems project to teach agronomic principles and crop management techniques, and to enhance communication skills. Provides a sample progress report instructions sheet which was used for the project. (Author/RT)

Genetic mapping and QTL analysis of agronomic traits in Indian Mucuna pruriens using an intraspecific F₂population.

PubMed

Mahesh, S; Leelambika, M; Jaheer, Md; Anithakumari, A M; Sathyanarayana, N

2016-03-01

Mucuna pruriens is a well-recognized agricultural and horticultural crop with important medicinal use. However, antinutritional factors in seed and adverse morphological characters have negatively affected its cultivation. To elucidate the genetic control of agronomic traits, an intraspecific genetic linkage map of Indian M. pruriens has been developed based on amplified fragment length polymorphism (AFLP) markers using 200 F₂ progenies derived from a cross between wild and cultivated genotypes. The resulting linkage map comprised 129 AFLP markers dispersed over 13 linkage groups spanning a total distance of 618.88 cM with an average marker interval of 4.79 cM. For the first time, three QTLs explaining about 6.05-14.77% of the corresponding total phenotypic variation for three quantitative (seed) traits and, eight QTLs explaining about 25.96% of the corresponding total phenotypic variation for three qualitative traits have been detected on four linkage groups. The map presented here will pave a way for mapping of genes/QTLs for the important agronomic and horticultural traits contrasting between the parents used in this study.

Characterization of bean (Phaseolus vulgaris L.) ecotype "Fagiolo occhio nero di Oliveto Citra" using agronomic, biochemical and molecular approaches.

PubMed

Zaccardelli, Massimo; Pentangelo, Alfonso; Tripodi, Pasquale

2013-09-15

Common bean (Phaseolus vulgaris) is the most important grain legume and plays a significant role in human nutrition being a major source of dietary protein and representing a rich source of minerals and certain vitamins. Several large germplasm collections have been established, which contain large amounts of genetic diversity, including wild and domesticated species. In this study agronomic, biochemical and molecular characterization of landrace bean named "Fagiolo occhio nero di Oliveto Citra" (Phaseolus vulgaris L.), is described. Seeds were obtained by local farmers and field trials were carried out during years 2009-2010, in the typical cultivation site (Oliveto Citra, Salerno Province), using two different densities of investment. During 2011, in order to evaluate the performance in different environments, field trials were conducted in three localities (Battipaglia, Oliveto Citra and Controne). Data analysis shows good adaptability across locations and similar grain yield using two spacing's of seeds. Morphological characterization and molecular analysis, using AFLP and Minisatellite molecular markers, were performed on ten "biotypes" collected from local farmers. Seeds characterization showed variability on the violet area surrounding the hilum (named as eye) while markers have provided useful information on relationships between biotypes. Biochemical analysis, which includes the contents of protein, minerals and antioxidants, shows how the composition is consistent with respect to other landraces and commercial cultivars. The landrace under study revealed genetic stability and good adaptation to cultivated environment with best performance in the native area. In addition, the bio-agronomic characteristics are in accord with studies reported in literature.

SPECIES DISTRIBUTIONS, SURROGACY, AND IMPORTANT CONSERVATION REGIONS IN CANADA

EPA Science Inventory

Conservation actions could be more efficient if there is congruence among taxa in the distribution of species. Patterns in the geographic distribution of species of six taxa were used to identify nationally important sites for conservation in Canada. Species richness and a meas...

The complete chloroplast genome of two Brassica species, Brassica nigra and B. Oleracea.

PubMed

Seol, Young-Joo; Kim, Kyunghee; Kang, Sang-Ho; Perumal, Sampath; Lee, Jonghoon; Kim, Chang-Kug

2017-03-01

The two Brassica species, Brassica nigra and Brassica oleracea, are important agronomic crops. The chloroplast genome sequences were generated by de novo assembly using whole genome next-generation sequences. The chloroplast genomes of B. nigra and B. oleracea were 153 633 bp and 153 366 bp in size, respectively, and showed conserved typical chloroplast structure. The both chloroplast genomes contained a total of 114 genes including 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis revealed that B. oleracea is closely related to B. rapa and B. napus but B. nigra is more diverse than the neighbor species Raphanus sativus.

Using abiotic variables to predict importance of sites for species representation.

PubMed

Albuquerque, Fabio; Beier, Paul

2015-10-01

In systematic conservation planning, species distribution data for all sites in a planning area are used to prioritize each site in terms of the site's importance toward meeting the goal of species representation. But comprehensive species data are not available in most planning areas and would be expensive to acquire. As a shortcut, ecologists use surrogates, such as occurrences of birds or another well-surveyed taxon, or land types defined from remotely sensed data, in the hope that sites that represent the surrogates also represent biodiversity. Unfortunately, surrogates have not performed reliably. We propose a new type of surrogate, predicted importance, that can be developed from species data for a q% subset of sites. With species data from this subset of sites, importance can be modeled as a function of abiotic variables available at no charge for all terrestrial areas on Earth. Predicted importance can then be used as a surrogate to prioritize all sites. We tested this surrogate with 8 sets of species data. For each data set, we used a q% subset of sites to model importance as a function of abiotic variables, used the resulting function to predict importance for all sites, and evaluated the number of species in the sites with highest predicted importance. Sites with the highest predicted importance represented species efficiently for all data sets when q = 25% and for 7 of 8 data sets when q = 20%. Predicted importance requires less survey effort than direct selection for species representation and meets representation goals well compared with other surrogates currently in use. This less expensive surrogate may be useful in those areas of the world that need it most, namely tropical regions with the highest biodiversity, greatest biodiversity loss, most severe lack of inventory data, and poorly developed protected area networks. © 2015 Society for Conservation Biology.

Fine-Tuning Tomato Agronomic Properties by Computational Genome Redesign

PubMed Central

Carrera, Javier; Fernández del Carmen, Asun; Fernández-Muñoz, Rafael; Rambla, Jose Luis; Pons, Clara; Jaramillo, Alfonso; Elena, Santiago F.; Granell, Antonio

2012-01-01

Considering cells as biofactories, we aimed to optimize its internal processes by using the same engineering principles that large industries are implementing nowadays: lean manufacturing. We have applied reverse engineering computational methods to transcriptomic, metabolomic and phenomic data obtained from a collection of tomato recombinant inbreed lines to formulate a kinetic and constraint-based model that efficiently describes the cellular metabolism from expression of a minimal core of genes. Based on predicted metabolic profiles, a close association with agronomic and organoleptic properties of the ripe fruit was revealed with high statistical confidence. Inspired in a synthetic biology approach, the model was used for exploring the landscape of all possible local transcriptional changes with the aim of engineering tomato fruits with fine-tuned biotechnological properties. The method was validated by the ability of the proposed genomes, engineered for modified desired agronomic traits, to recapitulate experimental correlations between associated metabolites. PMID:22685389

Physiological and Agronomic Performance of the Coffee Crop in the Context of Climate Change and Global Warming: A Review.

PubMed

DaMatta, Fábio M; Avila, Rodrigo T; Cardoso, Amanda A; Martins, Samuel C V; Ramalho, José C

2018-05-30

Coffee is one of the most important global crops and provides a livelihood to millions of people living in developing countries. Coffee species have been described as being highly sensitive to climate change, as largely deduced from modeling studies based on predictions of rising temperatures and changing rainfall patterns. Here, we discuss the physiological responses of the coffee tree in the context of present and ongoing climate changes, including drought, heat, and light stresses, and interactions between these factors. We also summarize recent insights on the physiological and agronomic performance of coffee at elevated atmospheric CO 2 concentrations and highlight the key role of CO 2 in mitigating the harmful effects of heat stress. Evidence is shown suggesting that warming, per se, may be less harmful to coffee suitability than previously estimated, at least under the conditions of an adequate water supply. Finally, we discuss several mitigation strategies to improve crop performance in a changing world.

Unmanned Aerial Vehicles for High-Throughput Phenotyping and Agronomic Research

PubMed Central

Shi, Yeyin; Thomasson, J. Alex; Murray, Seth C.; Pugh, N. Ace; Rooney, William L.; Shafian, Sanaz; Rajan, Nithya; Rouze, Gregory; Morgan, Cristine L. S.; Neely, Haly L.; Rana, Aman; Bagavathiannan, Muthu V.; Henrickson, James; Bowden, Ezekiel; Valasek, John; Olsenholler, Jeff; Bishop, Michael P.; Sheridan, Ryan; Putman, Eric B.; Popescu, Sorin; Burks, Travis; Cope, Dale; Ibrahim, Amir; McCutchen, Billy F.; Baltensperger, David D.; Avant, Robert V.; Vidrine, Misty; Yang, Chenghai

2016-01-01

Advances in automation and data science have led agriculturists to seek real-time, high-quality, high-volume crop data to accelerate crop improvement through breeding and to optimize agronomic practices. Breeders have recently gained massive data-collection capability in genome sequencing of plants. Faster phenotypic trait data collection and analysis relative to genetic data leads to faster and better selections in crop improvement. Furthermore, faster and higher-resolution crop data collection leads to greater capability for scientists and growers to improve precision-agriculture practices on increasingly larger farms; e.g., site-specific application of water and nutrients. Unmanned aerial vehicles (UAVs) have recently gained traction as agricultural data collection systems. Using UAVs for agricultural remote sensing is an innovative technology that differs from traditional remote sensing in more ways than strictly higher-resolution images; it provides many new and unique possibilities, as well as new and unique challenges. Herein we report on processes and lessons learned from year 1—the summer 2015 and winter 2016 growing seasons–of a large multidisciplinary project evaluating UAV images across a range of breeding and agronomic research trials on a large research farm. Included are team and project planning, UAV and sensor selection and integration, and data collection and analysis workflow. The study involved many crops and both breeding plots and agronomic fields. The project’s goal was to develop methods for UAVs to collect high-quality, high-volume crop data with fast turnaround time to field scientists. The project included five teams: Administration, Flight Operations, Sensors, Data Management, and Field Research. Four case studies involving multiple crops in breeding and agronomic applications add practical descriptive detail. Lessons learned include critical information on sensors, air vehicles, and configuration parameters for both. As the first

Tracing QTLs for Leaf Blast Resistance and Agronomic Performance of Finger Millet (Eleusine coracana (L.) Gaertn.) Genotypes through Association Mapping and in silico Comparative Genomics Analyses.

PubMed

Ramakrishnan, M; Antony Ceasar, S; Duraipandiyan, V; Vinod, K K; Kalpana, Krishnan; Al-Dhabi, N A; Ignacimuthu, S

2016-01-01

Finger millet is one of the small millets with high nutritive value. This crop is vulnerable to blast disease caused by Pyricularia grisea, which occurs annually during rainy and winter seasons. Leaf blast occurs at early crop stage and is highly damaging. Mapping of resistance genes and other quantitative trait loci (QTLs) for agronomic performance can be of great use for improving finger millet genotypes. Evaluation of one hundred and twenty-eight finger millet genotypes in natural field conditions revealed that leaf blast caused severe setback on agronomic performance for susceptible genotypes, most significant traits being plant height and root length. Plant height was reduced under disease severity while root length was increased. Among the genotypes, IE4795 showed superior response in terms of both disease resistance and better agronomic performance. A total of seven unambiguous QTLs were found to be associated with various agronomic traits including leaf blast resistance by association mapping analysis. The markers, UGEP101 and UGEP95, were strongly associated with blast resistance. UGEP98 was associated with tiller number and UGEP9 was associated with root length and seed yield. Cross species validation of markers revealed that 12 candidate genes were associated with 8 QTLs in the genomes of grass species such as rice, foxtail millet, maize, Brachypodium stacei, B. distachyon, Panicum hallii and switchgrass. Several candidate genes were found proximal to orthologous sequences of the identified QTLs such as 1,4-β-glucanase for leaf blast resistance, cytokinin dehydrogenase (CKX) for tiller production, calmodulin (CaM) binding protein for seed yield and pectin methylesterase inhibitor (PMEI) for root growth and development. Most of these QTLs and their putatively associated candidate genes are reported for first time in finger millet. On validation, these novel QTLs may be utilized in future for marker assisted breeding for the development of fungal

Tracing QTLs for Leaf Blast Resistance and Agronomic Performance of Finger Millet (Eleusine coracana (L.) Gaertn.) Genotypes through Association Mapping and in silico Comparative Genomics Analyses

PubMed Central

Ramakrishnan, M.; Antony Ceasar, S.; Duraipandiyan, V.; Vinod, K. K.; Kalpana, Krishnan; Al-Dhabi, N. A.; Ignacimuthu, S.

2016-01-01

Finger millet is one of the small millets with high nutritive value. This crop is vulnerable to blast disease caused by Pyricularia grisea, which occurs annually during rainy and winter seasons. Leaf blast occurs at early crop stage and is highly damaging. Mapping of resistance genes and other quantitative trait loci (QTLs) for agronomic performance can be of great use for improving finger millet genotypes. Evaluation of one hundred and twenty-eight finger millet genotypes in natural field conditions revealed that leaf blast caused severe setback on agronomic performance for susceptible genotypes, most significant traits being plant height and root length. Plant height was reduced under disease severity while root length was increased. Among the genotypes, IE4795 showed superior response in terms of both disease resistance and better agronomic performance. A total of seven unambiguous QTLs were found to be associated with various agronomic traits including leaf blast resistance by association mapping analysis. The markers, UGEP101 and UGEP95, were strongly associated with blast resistance. UGEP98 was associated with tiller number and UGEP9 was associated with root length and seed yield. Cross species validation of markers revealed that 12 candidate genes were associated with 8 QTLs in the genomes of grass species such as rice, foxtail millet, maize, Brachypodium stacei, B. distachyon, Panicum hallii and switchgrass. Several candidate genes were found proximal to orthologous sequences of the identified QTLs such as 1,4-β-glucanase for leaf blast resistance, cytokinin dehydrogenase (CKX) for tiller production, calmodulin (CaM) binding protein for seed yield and pectin methylesterase inhibitor (PMEI) for root growth and development. Most of these QTLs and their putatively associated candidate genes are reported for first time in finger millet. On validation, these novel QTLs may be utilized in future for marker assisted breeding for the development of fungal

DNA barcoding commercially important fish species of Turkey.

PubMed

Keskın, Emre; Atar, Hasan H

2013-09-01

DNA barcoding was used in the identification of 89 commercially important freshwater and marine fish species found in Turkish ichthyofauna. A total of 1765 DNA barcodes using a 654-bp-long fragment of the mitochondrial cytochrome c oxidase subunit I gene were generated for 89 commercially important freshwater and marine fish species found in Turkish ichthyofauna. These species belong to 70 genera, 40 families and 19 orders from class Actinopterygii, and all were associated with a distinct DNA barcode. Nine and 12 of the COI barcode clusters represent the first species records submitted to the BOLD and GenBank databases, respectively. All COI barcodes (except sequences of first species records) were matched with reference sequences of expected species, according to morphological identification. Average nucleotide frequencies of the data set were calculated as T = 29.7%, C = 28.2%, A = 23.6% and G = 18.6%. Average pairwise genetic distance among individuals were estimated as 0.32%, 9.62%, 17,90% and 22.40% for conspecific, congeneric, confamilial and within order, respectively. Kimura 2-parameter genetic distance values were found to increase with taxonomic level. For most of the species analysed in our data set, there is a barcoding gap, and an overlap in the barcoding gap exists for only two genera. Neighbour-joining trees were drawn based on DNA barcodes and all the specimens clustered in agreement with their taxonomic classification at species level. Results of this study supported DNA barcoding as an efficient molecular tool for a better monitoring, conservation and management of fisheries. © 2013 John Wiley & Sons Ltd.

Biodiversity of Aspergillus species in some important agricultural products.

PubMed

Perrone, G; Susca, A; Cozzi, G; Ehrlich, K; Varga, J; Frisvad, J C; Meijer, M; Noonim, P; Mahakarnchanakul, W; Samson, R A

2007-01-01

The genus Aspergillus is one of the most important filamentous fungal genera. Aspergillus species are used in the fermentation industry, but they are also responsible of various plant and food secondary rot, with the consequence of possible accumulation of mycotoxins. The aflatoxin producing A. flavus and A. parasiticus, and ochratoxinogenic A. niger, A. ochraceus and A. carbonarius species are frequently encountered in agricultural products. Studies on the biodiversity of toxigenic Aspergillus species is useful to clarify molecular, ecological and biochemical characteristics of the different species in relation to their different adaptation to environmental and geographical conditions, and to their potential toxigenicity. Here we analyzed the biodiversity of ochratoxin producing species occurring on two important crops: grapes and coffee, and the genetic diversity of A. flavus populations occurring in agricultural fields. Altogether nine different black Aspergillus species can be found on grapes which are often difficult to identify with classical methods. The polyphasic approach used in our studies led to the identification of three new species occurring on grapes: A. brasiliensis, A. ibericus, and A. uvarum. Similar studies on the Aspergillus species occurring on coffee beans have evidenced in the last five years that A. carbonarius is an important source of ochratoxin A in coffee. Four new species within the black aspergilli were also identified in coffee beans: A. sclerotioniger, A. lacticoffeatus, A. sclerotiicarbonarius, and A. aculeatinus. The genetic diversity within A. flavus populations has been widely studied in relation to their potential aflatoxigenicity and morphological variants L- and S-strains. Within A. flavus and other Aspergillus species capable of aflatoxin production, considerable diversity is found. We summarise the main recent achievements in the diversity of the aflatoxin gene cluster in A. flavus populations, A. parasiticus and the non

Global value of GM rice: a review of expected agronomic and consumer benefits.

PubMed

Demont, Matty; Stein, Alexander J

2013-06-25

Unlike the other major crops, no genetically modified (GM) varieties of rice have been commercialized at a large scale. Within the next 2-3 years new transgenic rice varieties could be ready for regulatory approval and subsequent commercialization, though. Given the importance of rice as staple crop for many of the world's poorest people, this will have implications for the alleviation of poverty, hunger and malnutrition. Thus, policy-makers need to be aware of the potential benefits of GM rice. We provide an overview of the literature and discuss the evidence on expected agronomic and consumer benefits of genetically engineered rice. We find that while GM rice with improved agronomic traits could deliver benefits similar to already commercialized biotechnology crops, expected benefits of consumer traits could be higher by an order of magnitude. By aggregating the expected annual benefits, we estimate the global value of GM rice to be US$64 billion per year. This is only an indicative value, as more GM varieties will become available in future. Nevertheless, such a figure can help guide policy-makers when deciding on the approval or funding of biotechnology crops and it may also raise awareness among consumers about what is at stake for their societies. Copyright © 2013 Elsevier B.V. All rights reserved.

A Survey of Fertilizer Dealers: I. Sources of Agronomic Training.

ERIC Educational Resources Information Center

Schmitt, M. A.

1988-01-01

Reports on a survey of fertilizer dealers which was conducted to: assess where and from whom local fertilizer dealers obtain agronomic training; evaluate the effectiveness of various dealer training; and determine the needs and objectives of future training programs. (TW)

A Survey of Fertilizer Dealers: II. Sources of Agronomic Information.

ERIC Educational Resources Information Center

Schmitt, M. A.

1988-01-01

Reports on a survey of fertilizer dealers that was conducted to assess how the dealers were obtaining their agronomic information, aside from formal training sessions, and determine if these sources of information were satisfactory in fulfilling the dealers' needs. (TW)

Biochar: A synthesis of its agronomic impact beyond carbon sequestration

USDA-ARS?s Scientific Manuscript database

Biochar has been recently heralded as an amendment to revitalize degraded soils, improve soil carbon sequestration, increase agronomic productivity and enter into future carbon trading markets. However, scientific and economic technicalities may limit the ability of biochar to consistently deliver o...

Genome sequence of M6, a diploid inbred clone of the high-glycoalkaloid-producing tuber-bearing potato species Solanum chacoense, reveals residual heterozygosity.

PubMed

Leisner, Courtney P; Hamilton, John P; Crisovan, Emily; Manrique-Carpintero, Norma C; Marand, Alexandre P; Newton, Linsey; Pham, Gina M; Jiang, Jiming; Douches, David S; Jansky, Shelley H; Buell, C Robin

2018-05-01

Cultivated potato (Solanum tuberosum L.) is a highly heterozygous autotetraploid that presents challenges in genome analyses and breeding. Wild potato species serve as a resource for the introgression of important agronomic traits into cultivated potato. One key species is Solanum chacoense and the diploid, inbred clone M6, which is self-compatible and has desirable tuber market quality and disease resistance traits. Sequencing and assembly of the genome of the M6 clone of S. chacoense generated an assembly of 825 767 562 bp in 8260 scaffolds with an N50 scaffold size of 713 602 bp. Pseudomolecule construction anchored 508 Mb of the genome assembly into 12 chromosomes. Genome annotation yielded 49 124 high-confidence gene models representing 37 740 genes. Comparative analyses of the M6 genome with six other Solanaceae species revealed a core set of 158 367 Solanaceae genes and 1897 genes unique to three potato species. Analysis of single nucleotide polymorphisms across the M6 genome revealed enhanced residual heterozygosity on chromosomes 4, 8 and 9 relative to the other chromosomes. Access to the M6 genome provides a resource for identification of key genes for important agronomic traits and aids in genome-enabled development of inbred diploid potatoes with the potential to accelerate potato breeding. © 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd.

Agronomic performance of five banana cultivars under protected cultivation

USDA-ARS?s Scientific Manuscript database

Banana has been grown both in open-field and protected cultivation in Turkey. So far protected cultivation is very popular due to the high yield and quality. The objective of the study was to evaluate agronomic performance of five new banana cultivars under plastic greenhouse. ‘MA 13’, ‘Williams’, ‘...

Unmanned aerial vehicles for high-throughput phenotyping and agronomic research

USDA-ARS?s Scientific Manuscript database

Advances in automation and data science have led agriculturists to seek real-time, high-quality, high-volume crop data to accelerate crop improvement through breeding and to optimize agronomic practices. Breeders have recently gained massive data-collection capability in genome sequencing of plants....

Phytochemicals of Brassicaceae in plant protection and human health--influences of climate, environment and agronomic practice.

PubMed

Björkman, Maria; Klingen, Ingeborg; Birch, Andrew N E; Bones, Atle M; Bruce, Toby J A; Johansen, Tor J; Meadow, Richard; Mølmann, Jørgen; Seljåsen, Randi; Smart, Lesley E; Stewart, Derek

2011-05-01

In this review, we provide an overview of the role of glucosinolates and other phytochemical compounds present in the Brassicaceae in relation to plant protection and human health. Current knowledge of the factors that influence phytochemical content and profile in the Brassicaceae is also summarized and multi-factorial approaches are briefly discussed. Variation in agronomic conditions (plant species, cultivar, developmental stage, plant organ, plant competition, fertilization, pH), season, climatic factors, water availability, light (intensity, quality, duration) and CO(2) are known to significantly affect content and profile of phytochemicals. Phytochemicals such as the glucosinolates and leaf surface waxes play an important role in interactions with pests and pathogens. Factors that affect production of phytochemicals are important when designing plant protection strategies that exploit these compounds to minimize crop damage caused by plant pests and pathogens. Brassicaceous plants are consumed increasingly for possible health benefits, for example, glucosinolate-derived effects on degenerative diseases such as cancer, cardiovascular and neurodegenerative diseases. Thus, factors influencing phytochemical content and profile in the production of brassicaceous plants are worth considering both for plant and human health. Even though it is known that factors that influence phytochemical content and profile may interact, studies of plant compounds were, until recently, restricted by methods allowing only a reductionistic approach. It is now possible to design multi-factorial experiments that simulate their combined effects. This will provide important information to ecologists, plant breeders and agronomists. Copyright © 2011 Elsevier Ltd. All rights reserved.

Allergens/Antigens, toxins and polyketides of important Aspergillus species.

PubMed

Bhetariya, Preetida J; Madan, Taruna; Basir, Seemi Farhat; Varma, Anupam; Usha, Sarma P

2011-04-01

The medical, agricultural and biotechnological importance of the primitive eukaryotic microorganisms, the Fungi was recognized way back in 1920. Among various groups of fungi, the Aspergillus species are studied in great detail using advances in genomics and proteomics to unravel biological and molecular mechanisms in these fungi. Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, Aspergillus nidulans and Aspergillus terreus are some of the important species relevant to human, agricultural and biotechnological applications. The potential of Aspergillus species to produce highly diversified complex biomolecules such as multifunctional proteins (allergens, antigens, enzymes) and polyketides is fascinating and demands greater insight into the understanding of these fungal species for application to human health. Recently a regulator gene for secondary metabolites, LaeA has been identified. Gene mining based on LaeA has facilitated new metabolites with antimicrobial activity such as emericellamides and antitumor activity such as terrequinone A from A. nidulans. Immunoproteomic approach was reported for identification of few novel allergens for A. fumigatus. In this context, the review is focused on recent developments in allergens, antigens, structural and functional diversity of the polyketide synthases that produce polyketides of pharmaceutical and biological importance. Possible antifungal drug targets for development of effective antifungal drugs and new strategies for development of molecular diagnostics are considered.

Evaluating the potential for weed seed dispersal based on waterfowl consumption and seed viability

USGS Publications Warehouse

Farmer, Jaime A.; Webb, Elisabeth B.; Pierce, Robert A.; Bradley, Kevin W.

2017-01-01

BACKGROUNDMigratory waterfowl have often been implicated in the movement of troublesome agronomic and wetland weed species. However, minimal research has been conducted to investigate the dispersal of agronomically important weed species by waterfowl. The two objectives for this project were to determine what weed species are being consumed by ducks and snow geese, and to determine the recovery rate and viability of 13 agronomic weed species after passage through a duck's digestive system.RESULTSSeed recovered from digestive tracts of 526 ducks and geese harvested during a 2‐year field study had 35 020 plants emerge. A greater variety of plant species emerged from ducks each year (47 and 31 species) compared to geese (11 and 3 species). Viable seed from 11 of 13 weed species fed to ducks in a controlled feeding study were recovered. Viability rate and gut retention times indicated potential dispersal up to 2900 km from the source depending on seed characteristics and variability in waterfowl dispersal distances.CONCLUSIONSStudy results confirm that waterfowl are consuming seeds from a variety of agronomically important weed species, including Palmer amaranth, which can remain viable after passage through digestive tracts and have potential to be dispersed over long distances by waterfowl.

Evaluating the potential for weed seed dispersal based on waterfowl consumption and seed viability.

PubMed

Farmer, Jaime A; Webb, Elisabeth B; Pierce, Robert A; Bradley, Kevin W

2017-12-01

Migratory waterfowl have often been implicated in the movement of troublesome agronomic and wetland weed species. However, minimal research has been conducted to investigate the dispersal of agronomically important weed species by waterfowl. The two objectives for this project were to determine what weed species are being consumed by ducks and snow geese, and to determine the recovery rate and viability of 13 agronomic weed species after passage through a duck's digestive system. Seed recovered from digestive tracts of 526 ducks and geese harvested during a 2-year field study had 35 020 plants emerge. A greater variety of plant species emerged from ducks each year (47 and 31 species) compared to geese (11 and 3 species). Viable seed from 11 of 13 weed species fed to ducks in a controlled feeding study were recovered. Viability rate and gut retention times indicated potential dispersal up to 2900 km from the source depending on seed characteristics and variability in waterfowl dispersal distances. Study results confirm that waterfowl are consuming seeds from a variety of agronomically important weed species, including Palmer amaranth, which can remain viable after passage through digestive tracts and have potential to be dispersed over long distances by waterfowl. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Assessment of agronomic homogeneity and compatibility of soils in the Vladimir Opolie region

NASA Astrophysics Data System (ADS)

Shein, E. V.; Kiryushin, V. I.; Korchagin, A. A.; Mazirov, M. A.; Dembovetskii, A. V.; Il'in, L. I.

2017-10-01

Complexes of gray forest soils of different podzolization degrees with the participation of gray forest podzolized soils with the second humus horizon play a noticeable role in the soil cover patterns of Vladimir Opolie. The agronomic homogeneity and agronomic compatibility of gray forest soils in automorphic positions ("plakor" sites) were assessed on the test field of the Vladimir Agricultural Research Institute. The term "soil homogeneity" implies in our study the closeness of crop yield estimates (scores) for the soil polygons; the term "soil compatibility" implies the possibility to apply the same technologies in the same dates for different soil polygons within a field. To assess the agronomic homogeneity and compatibility of soils, the statistical analysis of the yields of test crop (oats) was performed, and the spatial distribution of the particular parameters of soil hydrothermic regime was studied. The analysis of crop yields showed their high variability: the gray forest soils on microhighs showed the minimal potential fertility, and the maximal fertility was typical of the soils with the second humus horizon in microlows. Soils also differed significantly in their hydrothermic regime, as the gray forest soils with the second humus horizon were heated and cooled slower than the background gray forest soils; their temperature had a stronger lag effect and displayed a narrower amplitude in seasonal fluctuations; and these soils were wetter during the first weeks (40 days) of the growing season. Being colder and wetter, the soils with the second humus horizons reached their physical ripeness later than the gray forest soils. Thus, the soil cover of the test plot in the automorphic position is heterogeneous; from the agronomic standpoint, its components are incompatible.

Agronomic effects of mutations in two soybean Stearoyl-ACP-Desaturases

USDA-ARS?s Scientific Manuscript database

Soybean [Glycine max (L.) Merr.] oil normally contains 2-4% stearic acid. Oil with higher levels of stearic acid is desired for use in the baking industry, for both its chemical properties and human health benefits. Several lines with increased stearic acid have been identified; however, the agronom...

QTL mapping for nine drought-responsive agronomic traits in bread wheat under irrigated and rain-fed environments

PubMed Central

Gahlaut, Vijay; Jaiswal, Vandana; Tyagi, Bhudeva S.; Singh, Gyanendra; Sareen, Sindhu; Balyan, Harindra S.

2017-01-01

In bread wheat, QTL interval mapping was conducted for nine important drought responsive agronomic traits. For this purpose, a doubled haploid (DH) mapping population derived from Kukri/Excalibur was grown over three years at four separate locations in India, both under irrigated and rain-fed environments. Single locus analysis using composite interval mapping (CIM) allowed detection of 98 QTL, which included 66 QTL for nine individual agronomic traits and 32 QTL, which affected drought sensitivity index (DSI) for the same nine traits. Two-locus analysis allowed detection of 19 main effect QTL (M-QTL) for four traits (days to anthesis, days to maturity, grain filling duration and thousand grain weight) and 19 pairs of epistatic QTL (E-QTL) for two traits (days to anthesis and thousand grain weight). Eight QTL were common in single locus analysis and two locus analysis. These QTL (identified both in single- and two-locus analysis) were distributed on 20 different chromosomes (except 4D). Important genomic regions on chromosomes 5A and 7A were also identified (5A carried QTL for seven traits and 7A carried QTL for six traits). Marker-assisted recurrent selection (MARS) involving pyramiding of important QTL reported in the present study, together with important QTL reported earlier, may be used for improvement of drought tolerance in wheat. In future, more closely linked markers for the QTL reported here may be developed through fine mapping, and the candidate genes may be identified and used for developing a better understanding of the genetic basis of drought tolerance in wheat. PMID:28793327

Association of green stem disorder with agronomic traits in soybean

USDA-ARS?s Scientific Manuscript database

Green stem disorder (GSD) of soybean is the occurrence of non-senescent, fleshy green stems of plants with normal, fully mature pods and seeds. The main focus of this study was to determine the relationship between GSD incidence and agronomic traits and to determine if GSD incidence was associated w...

Genomic Analyses Yield Markers for Identifying Agronomically Important Genes in Potato

USDA-ARS?s Scientific Manuscript database

This study explores the genetic architecture underling the potato evolution through a comprehensive assessment of wild and cultivated potato species based on the re-sequencing of 201 accessions of Solanum section Petota with >12 × genome coverage. We identified 450 domesticated genes, which showed e...

Species invasion shifts the importance of predator dependence.

PubMed

Griffen, Blaine D; Delaney, David G

2007-12-01

The strength of interference between foraging individuals can influence per capita consumption rates, with important consequences for predator and prey populations and system stability. Here we demonstrate how the replacement of a previously established invader, the predatory crab Carcinus maenas, by the recently invading predatory crab Hemigrapsus sanguineus shifts predation from a species that experiences strong predator interference (strong predator dependence) to one that experiences weak predator interference (weak predator dependence). We demonstrate using field experiments that differences in the strength of predator dependence persist for these species both when they forage on a single focal prey species only (the mussel Mytilus edulis) and when they forage more broadly across the entire prey community. This shift in predator dependence with species replacement may be altering the biomass across trophic levels, consistent with theoretical predictions, as we show that H. sanguineus populations are much larger than C. maenas populations throughout their invaded ranges. Our study highlights that predator dependence may differ among predator species and demonstrates that different predatory impacts of two conspicuous invasive predators may be explained at least in part by different strengths of predator dependence.

[Comparative analysis of agronomic and qualitative characters in different lines of Dendrobium denneanum].

PubMed

He, Tao; Deng, Li; Lin, Yuan; Li, Bo; Yang, Xiaofan; Wang, Fang; Chun, Ze

2010-08-01

To provide theoretical basis for breeding good variety of Dendrobium denneanum, agronomic and qualitative characters of 4 different lines and relationships among them were studied. The stem length, stem diameter, leaf length, leaf width, length/ width ratio and leaf area were measured. The single fresh and dry stem was weighed and drying rate was calculated. The contents of polysaccharides and total alkaloids were determined by sulfuric acid-phenol colorimetry and acid-dye colorimetry, respectively. The correlations between characters were analyzed. The results showed that differences in major agronomic characters between four lines were significant. The plant types of dq-1 and dq-2 were higher, dq-3 was medium and dq-4 was lower. The fresh weigh of stem and content of polysaccharides were the highest in dq-2, 7.81 g and 14.33%. While the highest content of total alkaloids and was 0. 486% in dq-3. There were significant correlations between agronomic characters, but these characters had low or non correlations with qualitative characters such as polysaccharides and total alkaloids. It was shown that the content of polysaccharides and total alkaloids were significantly different among 4 lines of D. denneanum, which could be selected for different uses.

Cultivar x binary mixture interaction effect on agronomic traits in orchardgrass

USDA-ARS?s Scientific Manuscript database

A study was conducted to evaluate and characterize the agronomic value, including dry matter yield and forage quality of 25 orchardgrass cultivars grown in monoculture and binary mixtures with alfalfa under supplemental irrigation from 2009 to 2012 at a Millville, UT, field site. Orchardgrass monoc...

Agronomic Traits and Molecular Marker Identification of Wheat–Aegilops caudata Addition Lines

PubMed Central

Gong, Wenping; Han, Ran; Li, Haosheng; Song, Jianmin; Yan, Hongfei; Li, Genying; Liu, Aifeng; Cao, Xinyou; Guo, Jun; Zhai, Shengnan; Cheng, Dungong; Zhao, Zhendong; Liu, Cheng; Liu, Jianjun

2017-01-01

Aegilops caudata is an important gene source for wheat breeding. Intensive evaluation of its utilization value is an essential first step prior to its application in breeding. In this research, the agronomical and quality traits of Triticum aestivum-Ae. caudata additions B–G (homoeologous groups not identified) were analyzed and evaluated. Disease resistance tests showed that chromosome D of Ae. caudata might possess leaf rust resistance, and chromosome E might carry stem rust and powdery mildew resistance genes. Investigations into agronomical traits suggested that the introduction of the Ae. caudata chromosome in addition line F could reduce plant height. Grain quality tests showed that the introduction of chromosomes E or F into wheat could increase its protein and wet gluten content. Therefore, wheat-Ae. caudata additions D–F are all potentially useful candidates for chromosome engineering activities to create useful wheat-alien chromosome introgressions. A total of 55 EST-based molecular markers were developed and then used to identify the chromosome homoeologous group of each of the Ae. caudata B–G chromosomes. Marker analysis indicated that the Ae. caudata chromosomes in addition lines B to G were structurally altered, therefore, a large population combined with intensive screening pressure should be taken into consideration when inducing and screening for wheat-Ae. caudata compensating translocations. Marker data also indicated that the Ae. caudata chromosomes in addition lines C–F were 5C, 6C, 7C, and 3C, respectively, while the homoeologous group of chromosomes B and G of Ae. caudata are as yet undetermined and need further research. PMID:29075275

Phytoextraction of Zn and Cu from sewage sludge and impact on agronomic characteristics.

PubMed

Xiaomei, Liu; Qitang, Wu; Banks, M K; Ebbs, S D

2005-01-01

The presence of elevated concentrations of heavy metals limits the usage of sewage sludge as a fertilizer and soil amendment. Experiments were carried out to examine the extent to which seven plant species phytoextracted Zn and Cu from dewatered sludge. The hyperaccumulators Thlaspi caerulescens and Sedum alfredii showed the greatest removal of Zn, while shoots and tubers of two species of Alocasia showed the greatest Cu removal. Cultivation of plants in the sludge resulted in significant decreases in total Zn and changes in the partitioning of Zn between soil pools. However, Cu levels were largely unchanged and remained associated predominantly with the organic matter pool. Agronomic characteristics of the sludge material, such as pH, organic matter content, and nitrogen, phosphorus, and potassium concentrations, did not change significantly during the four-month growth period, indicating that subsequent crops could be sustained by this material. These results suggest that Zn can be phytoextracted from sludge material, provided the rate of metal uptake exceeds the rate of mobilization to the exchangeable fraction. Since there was no appreciable accumulation of Zn and Cu in seeds of Zea mays in this study, some tissues from sludge-grown plants could potentially be used as animal fodder.

Cymbopogon species; ethnopharmacology, phytochemistry and the pharmacological importance.

PubMed

Avoseh, Opeyemi; Oyedeji, Opeoluwa; Rungqu, Pamela; Nkeh-Chungag, Benedicta; Oyedeji, Adebola

2015-04-23

Cymbopogon genus is a member of the family of Gramineae which are herbs known worldwide for their high essential oil content. They are widely distributed across all continents where they are used for various purposes. The commercial and medicinal uses of the various species of Cymbopogon are well documented. Ethnopharmacology evidence shows that they possess a wide array of properties that justifies their use for pest control, in cosmetics and as anti-inflammation agents. These plants may also hold promise as potent anti-tumor and chemopreventive drugs. The chemo-types from this genus have been used as biomarkers for their identification and classification. Pharmacological applications of Cymbopogon citratus are well exploited, though studies show that other species may also useful pharmaceutically. Hence this literature review intends to discuss these species and explore their potential economic importance.

[Rationality of commodity criteria and traditional breeding of Polygala tenuifolia based on agronomic traits and determination of chemical components].

PubMed

Wang, Dan-Dan; Bai, Lu; Xu, Xiao-Shuang; Zhang, Fu-Sheng; Xing, Jie; Jia, Jin-Ping; Tian, Hong-Ling; Qin, Xue-Mei

2016-10-01

The agronomic traits (plant height, root diameter, root length, first lateral root height, lateral root amount, root weight) of 18 Polygala tenuifolia samples with different agronomic traits were analyzed, respectively. HPLC was used to analyze three main characteristic components including tenuifolin, polygalaxanthone Ⅲ, and 3,6'-disinapoyl sucrose. At last, the correlation between six agronomic traits and three main characteristic components were analyzed by scatter plot. We found no significant correlation between root diameter and three main characteristic components. There were no obvious correlations between tenuifolin and the remaining five agronomic traits. Short root length and first lateral root height as well as high lateral root amount resulted in high levels of polygalaxanthone Ⅲ in P. tenuifolia samples. High levels of 3,6'-disinapoyl sucrose were observed in P. tenuifolia samples with longer root. So, the current commodity criteria and traditional breeding of P. tenuifolia did not conform to pharmacopoeia standards, which excellent medicinal materials should have high contents of the main characteristic components. It was urgent to revise the current commodity criteria and breeding methods. Copyright© by the Chinese Pharmaceutical Association.

Forensically important flesh fly species in Thailand: morphology and developmental rate.

PubMed

Sukontason, Kom; Bunchu, Nophawan; Chaiwong, Tarinee; Moophayak, Kittikhun; Sukontason, Kabkaew L

2010-04-01

Forensically important flesh fly species in Thailand have been investigated for their larval morphology and developmental rate to increase the forensic entomology database in Thailand and nearby countries. Sarcophaga (Liosarcophaga) dux Thomson, Sarcophaga (Liopygia) ruficornis (Fabricius), and Sarcophaga (Boettcherisca) peregrina (Robineau-Desvoidy) are the species of greatest forensic importance. The third instars of these species are similar in morphological appearance, making it difficult or impossible to differentiate between them based on external morphological characteristics. This study compares these important characteristics and reveals that the most distinctive is the posterior spiracle, followed by the number of papillae on the anterior spiracle. For confirmation of these species, the unique characteristics of adult males are also shown for accurate identification. Both the third instar and adult male characteristics are keys to identifying these species. In addition, the developmental rate of S. dux was examined in northern Thailand during 2002-2003 under natural ambient temperature (approximately 24-28 degrees C) and a natural light/dark photoperiod (approximately 12:12 h), indicating relatively rapid larval development in summer (March-June), pre-pupae (stop moving) initiated at 72 h. In the rainy season (July-October), pre-pupae initiated at 72 or 96 h, whereas pre-pupae initiated at 96 h in winter.

A high density genetic map and QTL for agronomic and yield traits in Foxtail millet [Setaria italica (L.) P. Beauv].

PubMed

Fang, Xiaomei; Dong, Kongjun; Wang, Xiaoqin; Liu, Tianpeng; He, Jihong; Ren, Ruiyu; Zhang, Lei; Liu, Rui; Liu, Xueying; Li, Man; Huang, Mengzhu; Zhang, Zhengsheng; Yang, Tianyu

2016-05-04

Foxtail millet [Setaria italica (L.) P. Beauv.], a crop of historical importance in China, has been adopted as a model crop for studying C-4 photosynthesis, stress biology and biofuel traits. Construction of a high density genetic map and identification of stable quantitative trait loci (QTL) lay the foundation for marker-assisted selection for agronomic traits and yield improvement. A total of 10598 SSR markers were developed according to the reference genome sequence of foxtail millet cultivar 'Yugu1'. A total of 1013 SSR markers showing polymorphism between Yugu1 and Longgu7 were used to genotype 167 individuals from a Yugu1 × Longgu7 F2 population, and a high density genetic map was constructed. The genetic map contained 1035 loci and spanned 1318.8 cM with an average distance of 1.27 cM between adjacent markers. Based on agronomic and yield traits identified in 2 years, 29 QTL were identified for 11 traits with combined analysis and single environment analysis. These QTL explained from 7.0 to 14.3 % of phenotypic variation. Favorable QTL alleles for peduncle length originated from Longgu7 whereas favorable alleles for the other traits originated from Yugu1 except for qLMS6.1. New SSR markers, a high density genetic map and QTL identified for agronomic and yield traits lay the ground work for functional gene mapping, map-based cloning and marker-assisted selection in foxtail millet.

MPIC: a mitochondrial protein import components database for plant and non-plant species.

PubMed

Murcha, Monika W; Narsai, Reena; Devenish, James; Kubiszewski-Jakubiak, Szymon; Whelan, James

2015-01-01

In the 2 billion years since the endosymbiotic event that gave rise to mitochondria, variations in mitochondrial protein import have evolved across different species. With the genomes of an increasing number of plant species sequenced, it is possible to gain novel insights into mitochondrial protein import pathways. We have generated the Mitochondrial Protein Import Components (MPIC) Database (DB; http://www.plantenergy.uwa.edu.au/applications/mpic) providing searchable information on the protein import apparatus of plant and non-plant mitochondria. An in silico analysis was carried out, comparing the mitochondrial protein import apparatus from 24 species representing various lineages from Saccharomyces cerevisiae (yeast) and algae to Homo sapiens (human) and higher plants, including Arabidopsis thaliana (Arabidopsis), Oryza sativa (rice) and other more recently sequenced plant species. Each of these species was extensively searched and manually assembled for analysis in the MPIC DB. The database presents an interactive diagram in a user-friendly manner, allowing users to select their import component of interest. The MPIC DB presents an extensive resource facilitating detailed investigation of the mitochondrial protein import machinery and allowing patterns of conservation and divergence to be recognized that would otherwise have been missed. To demonstrate the usefulness of the MPIC DB, we present a comparative analysis of the mitochondrial protein import machinery in plants and non-plant species, revealing plant-specific features that have evolved. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Draft genome sequence of Cicer reticulatum L., the wild progenitor of chickpea provides a resource for agronomic trait improvement.

PubMed

Gupta, Sonal; Nawaz, Kashif; Parween, Sabiha; Roy, Riti; Sahu, Kamlesh; Kumar Pole, Anil; Khandal, Hitaishi; Srivastava, Rishi; Kumar Parida, Swarup; Chattopadhyay, Debasis

2017-02-01

Cicer reticulatum L. is the wild progenitor of the fourth most important legume crop chickpea (C. arietinum L.). We assembled short-read sequences into 416 Mb draft genome of C. reticulatum and anchored 78% (327 Mb) of this assembly to eight linkage groups. Genome annotation predicted 25,680 protein-coding genes covering more than 90% of predicted gene space. The genome assembly shared a substantial synteny and conservation of gene orders with the genome of the model legume Medicago truncatula. Resistance gene homologs of wild and domesticated chickpeas showed high sequence homology and conserved synteny. Comparison of gene sequences and nucleotide diversity using 66 wild and domesticated chickpea accessions suggested that the desi type chickpea was genetically closer to the wild species than the kabuli type. Comparative analyses predicted gene flow between the wild and the cultivated species during domestication. Molecular diversity and population genetic structure determination using 15,096 genome-wide single nucleotide polymorphisms revealed an admixed domestication pattern among cultivated (desi and kabuli) and wild chickpea accessions belonging to three population groups reflecting significant influence of parentage or geographical origin for their cultivar-specific population classification. The assembly and the polymorphic sequence resources presented here would facilitate the study of chickpea domestication and targeted use of wild Cicer germplasms for agronomic trait improvement in chickpea. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Introgression lines of Triticum aestivum x Aegilops tauschii: Agronomic and nutritional value

USDA-ARS?s Scientific Manuscript database

Eighty-five single homozygous substitution lines (SLs) of the Aegilops tauschii D genome in Chinese Spring (CS) hexaploid wheat (Triticum aestivum L.) genetic background were evaluated for agronomic, phenotypic and ionome profiles during three years of field experiments. An augmented design with a r...

Species mobility and landscape context determine the importance of local and landscape-level attributes.

PubMed

Fuentes-Montemayor, Elisa; Watts, Kevin; Macgregor, Nicholas A; Lopez-Gallego, Zeltia; J Park, Kirsty

2017-07-01

Conservation strategies to tackle habitat loss and fragmentation require actions at the local (e.g., improving/expanding existing habitat patches) and landscape level (e.g., creating new habitat in the matrix). However, the relative importance of these actions for biodiversity is still poorly understood, leading to debate on how to prioritize conservation activities. Here, we assess the relative importance of local vs. landscape-level attributes in determining the use of woodlands by bats in fragmented landscapes; we also compare the role of habitat amount in the surrounding landscape per se vs. a combination of both habitat amount and configuration and explore whether the relative importance of these attributes varies with species mobility and landscape context. We conducted acoustic surveys in 102 woodland patches in the UK that form part of the WrEN project (www.wren-project.com), a large-scale natural experiment designed to study the effects of 160 yr of woodland creation on biodiversity and inform landscape-scale conservation. We used multivariate analysis and a model-selection approach to assess the relative importance of local (e.g., vegetation structure) and landscape-level (e.g., amount/configuration of surrounding land types) attributes on bat occurrence and activity levels. Species mobility was an important trait determining the relative importance of local vs. landscape-level attributes for different bat species. Lower mobility species were most strongly influenced by local habitat quality; the landscape became increasingly important for higher mobility species. At the landscape-scale, a combination of habitat amount and configuration appeared more important than habitat amount alone for lower mobility species, while the opposite was observed for higher mobility species. Regardless of species mobility, landscape-level attributes appeared more important for bats in a more homogeneous and intensively farmed landscape. Conservation strategies involving

Agronomic Challenges and Opportunities for Smallholder Terrace Agriculture in Developing Countries.

PubMed

Chapagain, Tejendra; Raizada, Manish N

2017-01-01

Improving land productivity is essential to meet increasing food and forage demands in hillside and mountain communities. Tens of millions of smallholder terrace farmers in Asia, Africa, and Latin America who earn $1-2 per day do not have access to peer-reviewed knowledge of best agronomic practices, though they have considerable traditional ecological knowledge. Terrace farmers also lack access to affordable farm tools and inputs required to increase crop yields. The objectives of this review are to highlight the agronomic challenges of terrace farming, and offer innovative, low-cost solutions to intensify terrace agriculture while improving local livelihoods. The article focuses on smallholder farmers in developing nations, with particular reference to Nepal. The challenges of terrace agriculture in these regions include lack of quality land area for agriculture, erosion and loss of soil fertility, low yield, poor access to agricultural inputs and services, lack of mechanization, labor shortages, poverty, and illiteracy. Agronomic strategies that could help address these concerns include intensification of terraces using agro-ecological approaches along with introduction of light-weight, low-cost, and purchasable tools and affordable inputs that enhance productivity and reduce female drudgery. To package, deliver, and share these technologies with remote hillside communities, effective scaling up models are required. One opportunity to enable distribution of these products could be to "piggy-back" onto pre-existing snackfood/cigarette/alcohol distribution networks that are prevalent even in the most remote mountainous regions of the world. Such strategies, practices, and tools could be supported by formalized government policies dedicated to the well-being of terrace farmers and ecosystems, to maintain resiliency at a time of alarming climate change. We hope this review will inform governments, non-governmental organizations, and the private sector to draw

Agronomic Challenges and Opportunities for Smallholder Terrace Agriculture in Developing Countries

PubMed Central

Chapagain, Tejendra; Raizada, Manish N.

2017-01-01

Improving land productivity is essential to meet increasing food and forage demands in hillside and mountain communities. Tens of millions of smallholder terrace farmers in Asia, Africa, and Latin America who earn $1–2 per day do not have access to peer-reviewed knowledge of best agronomic practices, though they have considerable traditional ecological knowledge. Terrace farmers also lack access to affordable farm tools and inputs required to increase crop yields. The objectives of this review are to highlight the agronomic challenges of terrace farming, and offer innovative, low-cost solutions to intensify terrace agriculture while improving local livelihoods. The article focuses on smallholder farmers in developing nations, with particular reference to Nepal. The challenges of terrace agriculture in these regions include lack of quality land area for agriculture, erosion and loss of soil fertility, low yield, poor access to agricultural inputs and services, lack of mechanization, labor shortages, poverty, and illiteracy. Agronomic strategies that could help address these concerns include intensification of terraces using agro-ecological approaches along with introduction of light-weight, low-cost, and purchasable tools and affordable inputs that enhance productivity and reduce female drudgery. To package, deliver, and share these technologies with remote hillside communities, effective scaling up models are required. One opportunity to enable distribution of these products could be to “piggy-back” onto pre-existing snackfood/cigarette/alcohol distribution networks that are prevalent even in the most remote mountainous regions of the world. Such strategies, practices, and tools could be supported by formalized government policies dedicated to the well-being of terrace farmers and ecosystems, to maintain resiliency at a time of alarming climate change. We hope this review will inform governments, non-governmental organizations, and the private sector to draw

Carbon and water cycling in flooded and rainfed rice (Oryza Sativa) ecosystem: Disentangling agronomical and ecological aspects of water use efficiency

NASA Astrophysics Data System (ADS)

Nay-Htoon, Bhone; Xue, Wei; Dubbert, Maren; Lindner, Steve; Cuntz, Matthias; Ko, Jonghan; Tenhunen, John; Werner, Christiane

2015-04-01

Agricultural crops play an important role in the global carbon and water cycling process and there is intense research to understand and predict carbon and water fluxes, productivity and water use of cultivated crops under climate change. Mechanistic understanding of the trade of between ecosystem water use efficiency and agronomic water use efficiency to maintain higher crop yield and productive water loss is necessary for the ecosystem sustainability. . We compared water and carbon fluxes of paddy and rainfed rice by canopy scale gas exchange measurements, crop growth, and daily evapotranspiration, transpiration and carbon flux modeling. According to our findings, evaporation contributed strongly (maximum 100% to minimum 45%) to paddy rice evapotranspiration while transpiration of rainfed is almost 50 % of daily evapotranspiration. Water use efficiency (WUE) was higher in rainfed rice both from an agronomic (WUEagro, i.e. grain yield per evapotranspiration) and ecosystem (WUEeco, i.e. gross primary production per evapotranspiration) perspective. However, rainfed rice showed also high ecosystem respiration losses and a slightly lower crop yield, demonstrating that higher WUE in rainfed rice comes at the expense of higher respiration losses of assimilated carbon and lower plant production, compared to paddy rice. Our results highlighted the need to partition water and carbon fluxes to improve our mechanistic understanding of water use efficiency and environmental impact of different agricultural practices. Keywords: Rainfed rice, Paddy rice, water use efficiency, Transpiration/Evapotranspiration, ecosystem WUE, agronomic WUE, Evapotranspiration

Disease evaluations and agronomic traits of advanced peanut breeding lines in 2017

USDA-ARS?s Scientific Manuscript database

Disease evaluations of advanced peanut breeding lines are conducted annually to compare the agronomic traits (crop value, yield, seed grade and characteristics) and disease resistance in cultivars that are currently available or close to being released for the Southwest. In 2017, a total of 19 comm...

Linkages Among Agronomic, Environmental and Weed Management Characteristics in North American Sweet Corn

USDA-ARS?s Scientific Manuscript database

Performance of weed management systems varies greatly across the landscape in both growers’ fields and in experimental trials conducted by agricultural scientists. Using agronomic, environmental, and weed management information from growers’ fields and experimental trials, we identified dominant ch...

Agronomic performance of F1, F2 and F3 hybrids between weedy rice and transgenic glufosinate-resistant rice.

PubMed

Song, Xiaoling; Wang, Zhou; Qiang, Sheng

2011-08-01

Studies of hybrid fitness, of which agronomic performance may be an indicator, can help in evaluating the potential for introgression of a transgene from a transgenic crop to wild relatives. The objective of this study was to assess the agronomic performance of reciprocal hybrids between two transgenic glufosinate-resistant rice lines, Y0003 and 99-t, and two weedy rice accessions, WR1 and WR2, in the greenhouse. F1 hybrids displayed heterosis in height, flag leaf area and number of spikelets per panicle. The agronomic performance of F1 between WR1 and Y0003 was not affected by crossing direction. The tiller and panicle numbers of F1 individuals were higher than their F2 counterparts. However, these traits did not change significantly from the F2 to the F3 generation or in hybrids with weedy rice as maternal or paternal plants. For all hybrids, the in vitro germination rates of fresh pollen were similar and significantly lower than those of their parents, seed sets were similar to or of lower value than those of weedy rice parents and seed shattering characteristics were partially suppressed, but the survival of hybrids over winter in the field was similar to that of weedy rice parents. All F1, F2 and F3 hybrids had similar composite agronomic performance to weedy rice parents. There was no significant decrease in the composite agronomic performance of any of the hybrids compared with weedy rice. This implies that gene flow from transgenic cultivated rice to weedy rice could occur under natural conditions. Copyright © 2011 Society of Chemical Industry.

Oil Concentration and Fatty Acid Profile of Wild Helianthus Species fron the Southeastern United States

USDA-ARS?s Scientific Manuscript database

Sunflower (Helianthus annuus L.) oil has the potential to be improved for industrial and nutritional purposes through selection and breeding. The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from wild species and agronomic traits have been enhanced. Interes...

Helminth communities of four commercially important fish species from Chetumal Bay, Mexico.

PubMed

Aguirre-Macedo, M L; Vidal-Martínez, V M; González-Solís, D; Caballero, P I

2007-03-01

The relative importance of ecology and evolution as factors determining species richness and composition of the helminth communities of fish is a matter of current debate. Theoretical studies use host-parasite lists, but these do not include studies on a temporal or spatial scale. Local environmental conditions and host biological characteristics are shown to influence helminth species richness and composition in four fish species (Eugerres plumieri, Hexanematichthys assimilis, Oligoplites saurus, and Scomberomorus maculatus) in Chetumal Bay, Mexico. With the exception of H. assimilis, the helminth communities had not been previously studied and possible associations between environmental and host biological characteristics as factors determining helminth species richness and composition using redundancy analysis (RDA) are described. Thirty-four helminth species are identified, with the highest number of species (19 total (mean = 6.3 +/- 2.1)) and the lowest (9 (4.0 +/- 1.0)) occurring in H. assimilis and S. maculatus, respectively. The larval nematodes Contracaecum sp. and Pseudoterranova sp. were not only the helminth species shared by all four host species but also were the most prevalent and abundant. Statistical associations between helminth community parameters and local ecological variables such as host habitat use, feeding habits, mobility, and time of residence in coastal lagoons are identified. Phylogeny is important because it clearly separates all four host species by their specialist parasites, although specific habitat and feeding habits also significantly influence the differentiation between the four fish species.

Digester effluent’s agronomic and odor emission potential: A swine case study

USDA-ARS?s Scientific Manuscript database

This on-farm study looked at the full-scale treatment effects of anaerobic digestion on the composition of manure effluent from an agronomic and air quality perspective. The goal was to improve our understanding of the role that anaerobic digestion may play in managing manure as a fertilizer and in...

An agronomic field-scale sensor network for monitoring soil water and temperature variation

NASA Astrophysics Data System (ADS)

Brown, D. J.; Gasch, C.; Brooks, E. S.; Huggins, D. R.; Campbell, C. S.; Cobos, D. R.

2014-12-01

Environmental sensor networks have been deployed in a variety of contexts to monitor plant, air, water and soil properties. To date, there have been relatively few such networks deployed to monitor dynamic soil properties in cropped fields. Here we report on experience with a distributed soil sensor network that has been deployed for seven years in a research farm with ongoing agronomic field operations. The Washington State University R. J. Cook Agronomy Farm (CAF), Pullman, WA, USA has recently been designated a United States Department of Agriculture (USDA) Long-Term Agro-Ecosystem Research (LTAR) site. In 2007, 12 geo-referenced locations at CAF were instrumented, then in 2009 this network was expended to 42 locations distributed across the 37-ha farm. At each of this locations, Decagon 5TE probes (Decagon Devices Inc., Pullman, WA, USA) were installed at five depths (30, 60, 90, 120, and 150 cm), with temperature and volumetric soil moisture content recorded hourly. Initially, data loggers were wirelessly connected to a data station that could be accessed through a cell connection, but due to the logistics of agronomic field operations, we later buried the dataloggers at each site and now periodically download data via local radio transmission. In this presentation, we share our experience with the installation, maintenance, calibration and data processing associated with an agronomic soil monitoring network. We also present highlights of data derived from this network, including seasonal fluctuations of soil temperature and volumetric water content at each depth, and how these measurements are influenced by crop type, soil properties, landscape position, and precipitation events.

Agronomic Biofortification of Amaranthus dubius with Macro Nutrients and Vitamin A

NASA Astrophysics Data System (ADS)

Mala, R.; Celsia, A. S. Ruby; Mahalakshmi, R.; Rajeswari, S.

2017-08-01

Agronomic biofortification of Amaranthus dubius with carbohydrates, proteins and Vitamin A using Spirulina platensis is reported in the present preliminary study. S. platensis was applied basally to field and its influence on germination, concentration of proteins, carbohydrates, chlorophyll, carotenoids and antioxidant activity of leaves were assessed in CO1 variety of A. dubius. Biofortification of the nutrients were evaluated on 5th and 20th day. Germination was optimum at 0.005 % of S. platensis as a fertilizer and the agronomic fortifying agent. Germination in control was 82 % and 95 % in 0.005 % of S. platensis fortification. The concentration of total chlorophyll in control and biofortified leaf on 20th day were 85.6 mg/g and 325 mg/g of dried leaf. The concentration of proteins was 71.93 mg/g and 450 mg/g on 20th day in control and fortified leaves. S. platensis applied field produced leaves fortified with 1.27 % of vitamin A aldehyde. Antioxidant activity of control leaf was 34.85 % and it was significantly increased in fortified leaves to 87 %. Thus the study confirms the fortification of leaf with proteins, carbohydrates and vitamin A.

Responses of Crop Water Use Efficiency to Climate Change and Agronomic Measures in the Semiarid Area of Northern China

PubMed Central

Zhang, Jingting; Ren, Wei; An, Pingli; Pan, Zhihua; Wang, Liwei; Dong, Zhiqiang; He, Di; Yang, Jia; Pan, Shufen; Tian, Hanqin

2015-01-01

It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983–1999 and 2000–2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6–11.0% and 19.5–92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming. PMID:26336098

Responses of Crop Water Use Efficiency to Climate Change and Agronomic Measures in the Semiarid Area of Northern China.

PubMed

Zhang, Jingting; Ren, Wei; An, Pingli; Pan, Zhihua; Wang, Liwei; Dong, Zhiqiang; He, Di; Yang, Jia; Pan, Shufen; Tian, Hanqin

2015-01-01

It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983-1999 and 2000-2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6-11.0% and 19.5-92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming.

Ecology and genomics of an important crop wild relative as a prelude to agricultural innovation.

PubMed

von Wettberg, Eric J B; Chang, Peter L; Başdemir, Fatma; Carrasquila-Garcia, Noelia; Korbu, Lijalem Balcha; Moenga, Susan M; Bedada, Gashaw; Greenlon, Alex; Moriuchi, Ken S; Singh, Vasantika; Cordeiro, Matilde A; Noujdina, Nina V; Dinegde, Kassaye Negash; Shah Sani, Syed Gul Abbas; Getahun, Tsegaye; Vance, Lisa; Bergmann, Emily; Lindsay, Donna; Mamo, Bullo Erena; Warschefsky, Emily J; Dacosta-Calheiros, Emmanuel; Marques, Edward; Yilmaz, Mustafa Abdullah; Cakmak, Ahmet; Rose, Janna; Migneault, Andrew; Krieg, Christopher P; Saylak, Sevgi; Temel, Hamdi; Friesen, Maren L; Siler, Eleanor; Akhmetov, Zhaslan; Ozcelik, Huseyin; Kholova, Jana; Can, Canan; Gaur, Pooran; Yildirim, Mehmet; Sharma, Hari; Vadez, Vincent; Tesfaye, Kassahun; Woldemedhin, Asnake Fikre; Tar'an, Bunyamin; Aydogan, Abdulkadir; Bukun, Bekir; Penmetsa, R Varma; Berger, Jens; Kahraman, Abdullah; Nuzhdin, Sergey V; Cook, Douglas R

2018-02-13

Domesticated species are impacted in unintended ways during domestication and breeding. Changes in the nature and intensity of selection impart genetic drift, reduce diversity, and increase the frequency of deleterious alleles. Such outcomes constrain our ability to expand the cultivation of crops into environments that differ from those under which domestication occurred. We address this need in chickpea, an important pulse legume, by harnessing the diversity of wild crop relatives. We document an extreme domestication-related genetic bottleneck and decipher the genetic history of wild populations. We provide evidence of ancestral adaptations for seed coat color crypsis, estimate the impact of environment on genetic structure and trait values, and demonstrate variation between wild and cultivated accessions for agronomic properties. A resource of genotyped, association mapping progeny functionally links the wild and cultivated gene pools and is an essential resource chickpea for improvement, while our methods inform collection of other wild crop progenitor species.

Agronomic and chemical evaluation of smooth sumac, Rhus glabra

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

Campbell, T.A.

Smooth sumac (Rhus glabra) is a potential whole-plant source of polyphenol and oil. In a 2-yr evaluation of progenies from 14 Maryland, 1 northern Virginia, and 2 Georgia populations, highly significant variation (1% level) in vigor, number of plants surviving the seeding year, dry matter yield the seeding year, and number of tillers produced the second year was observed. In 15 entries, highly significant variation (1% level) in polyphenol + oil and in gallotannins was observed. Dry matter yields, extrapolated to Mg ha/sup -1/, ranged from 0.02 to 1.4 (for a single harvest), % polyphenol + oil from 19.4-31.1, andmore » % gallotannins (a class of polyphenols) from 9.8 to 15.7. It is suggested that significantly improved lines could be developed through breeding. Based on estimated ratios of sigma/sup 2//sub Entries//sigma/sup 2//sub Entries/ + sigma/sup 2/, genetic variation for most agronomic traits could be estimated with fair precision whereas variation for chemical traits could be affected substantially by nongenetic factors. Factor analysis indicated plants that would perform reasonably well over a 2-yr period could be selected on the basis of early seeding-year vigor scores. Selection for high amount of polyphenol + oil and gallotannins would have to be done independently of agronomic selection. Cutting frequencies should not exceed 2 x yr/sup -1/ or serious stand loss would occur.« less

Global Establishment Risk of Economically Important Fruit Fly Species (Tephritidae)

PubMed Central

Qin, Yujia; Paini, Dean R.; Wang, Cong; Fang, Yan; Li, Zhihong

2015-01-01

The global invasion of Tephritidae (fruit flies) attracts a great deal of attention in the field of plant quarantine and invasion biology because of their economic importance. Predicting which one in hundreds of potential invasive fruit fly species is most likely to establish in a region presents a significant challenge, but can be facilitated using a self organising map (SOM), which is able to analyse species associations to rank large numbers of species simultaneously with an index of establishment. A global presence/absence dataset including 180 economically significant fruit fly species in 118 countries was analysed using a SOM. We compare and contrast ranked lists from six countries selected from each continent, and also show that those countries geographically close were clustered together by the SOM analysis because they have similar fruit fly assemblages. These closely clustered countries therefore represent greater threats to each other as sources of invasive fruit fly species. Finally, we indicate how this SOM method could be utilized as an initial screen to support prioritizing fruit fly species for further research into their potential to invade a region. PMID:25588025

Quantitative trait loci mapping for Gibberella ear rot resistance and associated agronomic traits using genotyping-by-sequencing in maize.

PubMed

Kebede, Aida Z; Woldemariam, Tsegaye; Reid, Lana M; Harris, Linda J

2016-01-01

Unique and co-localized chromosomal regions affecting Gibberella ear rot disease resistance and correlated agronomic traits were identified in maize. Dissecting the mechanisms underlying resistance to Gibberella ear rot (GER) disease in maize provides insight towards more informed breeding. To this goal, we evaluated 410 recombinant inbred lines (RIL) for GER resistance over three testing years using silk channel and kernel inoculation techniques. RILs were also evaluated for agronomic traits like days to silking, husk cover, and kernel drydown rate. The RILs showed significant genotypic differences for all traits with above average to high heritability estimates. Significant (P < 0.01) but weak genotypic correlations were observed between disease severity and agronomic traits, indicating the involvement of agronomic traits in disease resistance. Common QTLs were detected for GER resistance and kernel drydown rate, suggesting the existence of pleiotropic genes that could be exploited to improve both traits at the same time. The QTLs identified for silk and kernel resistance shared some common regions on chromosomes 1, 2, and 8 and also had some regions specific to each tissue on chromosomes 9 and 10. Thus, effective GER resistance breeding could be achieved by considering screening methods that allow exploitation of tissue-specific disease resistance mechanisms and include kernel drydown rate either in an index or as indirect selection criterion.

Biology and management of two important Conyza weeds: a global review.

PubMed

Bajwa, Ali Ahsan; Sadia, Sehrish; Ali, Hafiz Haider; Jabran, Khawar; Peerzada, Arslan Masood; Chauhan, Bhagirath Singh

2016-12-01

Weed management is one of the prime concerns for sustainable crop production. Conyza bonariensis and Conyza canadensis are two of the most problematic, noxious, invasive and widespread weeds in modern-day agriculture. The biology, ecology and interference of C. bonariensis and C. canadensis have been reviewed here to highlight pragmatic management options. Both these species share a unique set of biological features, which enables them to invade and adapt a wide range of environmental conditions. Distinct reproductive biology and an efficient seed dispersal mechanism help these species to spread rapidly. Ability to interfere strongly and to host crop pests makes these two species worst weeds of cropping systems. These weed species cause 28-68 % yield loss in important field crops such as soybean and cotton every year. These weeds are more prevalent in no-till systems and, thus, becoming a major issue in conservation agriculture. Cultural practices such as crop rotations, seed rate manipulation, mulching, inter-row tillage and narrow row spacing may provide an effective control of these species. However, such methods are not feasible and applicable under all types of conditions. Different herbicides also provide a varying degree of control depending on crop, agronomic practices, herbicide dose, application time and season. However, both these species have evolved resistance against multiple herbicides, including glyphosate and paraquat. The use of alternative herbicides and integrated management strategies may provide better control of herbicide-resistant C. bonariensis and C. canadensis. Management plans based on the eco-biological interactions of these species may prove sustainable in the future.

The Importance of Species Name Synonyms in Literature Searches.

PubMed

Guala, Gerald F

2016-01-01

The synonyms of biological species names are shown to be an important component in comprehensive searches of electronic scientific literature databases but they are not well leveraged within the major literature databases examined. For accepted or valid species names in the Integrated Taxonomic Information System (ITIS) which have synonyms in the system, and which are found in citations within PLoS, PMC, PubMed or Scopus, both the percentage of species for which citations will not be found if synonyms are not used, and the percentage increase in number of citations found by including synonyms are very often substantial. However, there is no correlation between the number of synonyms per species and the magnitude of the effect. Further, the number of citations found does not generally increase proportionally to the number of synonyms available. Users looking for literature on specific species across all of the resources investigated here are often missing large numbers of citations if they are not manually augmenting their searches with synonyms. Of course, missing citations can have serious consequences by effectively hiding critical information. Literature searches should include synonym relationships and a new web service in ITIS, with examples of how to apply it to this issue, was developed as a result of this study, and is here announced, to aide in this.

The importance of species name synonyms in literature searches

USGS Publications Warehouse

Guala, Gerald

2016-01-01

The synonyms of biological species names are shown to be an important component in comprehensive searches of electronic scientific literature databases but they are not well leveraged within the major literature databases examined. For accepted or valid species names in the Integrated Taxonomic Information System (ITIS) which have synonyms in the system, and which are found in citations within PLoS, PMC, PubMed or Scopus, both the percentage of species for which citations will not be found if synonyms are not used, and the percentage increase in number of citations found by including synonyms are very often substantial. However, there is no correlation between the number of synonyms per species and the magnitude of the effect. Further, the number of citations found does not generally increase proportionally to the number of synonyms available. Users looking for literature on specific species across all of the resources investigated here are often missing large numbers of citations if they are not manually augmenting their searches with synonyms. Of course, missing citations can have serious consequences by effectively hiding critical information. Literature searches should include synonym relationships and a new web service in ITIS, with examples of how to apply it to this issue, was developed as a result of this study, and is here announced, to aide in this.

Construction of a genetic linkage map and analysis of quantitative trait loci associated with the agronomically important traits of Pleurotus eryngii.

PubMed

Im, Chak Han; Park, Young-Hoon; Hammel, Kenneth E; Park, Bokyung; Kwon, Soon Wook; Ryu, Hojin; Ryu, Jae-San

2016-07-01

Breeding new strains with improved traits is a long-standing goal of mushroom breeders that can be expedited by marker-assisted selection (MAS). We constructed a genetic linkage map of Pleurotus eryngii based on segregation analysis of markers in postmeiotic monokaryons from KNR2312. In total, 256 loci comprising 226 simple sequence-repeat (SSR) markers, 2 mating-type factors, and 28 insertion/deletion (InDel) markers were mapped. The map consisted of 12 linkage groups (LGs) spanning 1047.8cM, with an average interval length of 4.09cM. Four independent populations (Pd3, Pd8, Pd14, and Pd15) derived from crossing between four monokaryons from KNR2532 as a tester strain and 98 monokaryons from KNR2312 were used to characterize quantitative trait loci (QTL) for nine traits such as yield, quality, cap color, and earliness. Using composite interval mapping (CIM), 71 QTLs explaining between 5.82% and 33.17% of the phenotypic variations were identified. Clusters of more than five QTLs for various traits were identified in three genomic regions, on LGs 1, 7 and 9. Regardless of the population, 6 of the 9 traits studied and 18 of the 71 QTLs found in this study were identified in the largest cluster, LG1, in the range from 65.4 to 110.4cM. The candidate genes for yield encoding transcription factor, signal transduction, mycelial growth and hydrolase are suggested by using manual and computational analysis of genome sequence corresponding to QTL region with the highest likelihood odds (LOD) for yield. The genetic map and the QTLs established in this study will help breeders and geneticists to develop selection markers for agronomically important characteristics of mushrooms and to identify the corresponding genes. Copyright © 2016 Elsevier Inc. All rights reserved.

Copper accumulation in vineyard soils: Rhizosphere processes and agronomic practices to limit its toxicity.

PubMed

Brunetto, Gustavo; Bastos de Melo, George Wellington; Terzano, Roberto; Del Buono, Daniele; Astolfi, Stefania; Tomasi, Nicola; Pii, Youry; Mimmo, Tanja; Cesco, Stefano

2016-11-01

Viticulture represents an important agricultural practice in many countries worldwide. Yet, the continuous use of fungicides has caused copper (Cu) accumulation in soils, which represent a major environmental and toxicological concern. Despite being an important micronutrient, Cu can be a potential toxicant at high concentrations since it may cause morphological, anatomical and physiological changes in plants, decreasing both food productivity and quality. Rhizosphere processes can, however, actively control the uptake and translocation of Cu in plants. In particular, root exudates affecting the chemical, physical and biological characteristics of the rhizosphere, might reduce the availability of Cu in the soil and hence its absorption. In addition, this review will aim at discussing the advantages and disadvantages of agronomic practices, such as liming, the use of pesticides, the application of organic matter, biochar and coal fly ashes, the inoculation with bacteria and/or mycorrhizal fungi and the intercropping, in alleviating Cu toxicity symptoms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Capparis spinosa L. in A Systematic Review: A Xerophilous Species of Multi Values and Promising Potentialities for Agrosystems under the Threat of Global Warming.

PubMed

Chedraoui, Stephanie; Abi-Rizk, Alain; El-Beyrouthy, Marc; Chalak, Lamis; Ouaini, Naim; Rajjou, Loïc

2017-01-01

Caper ( Capparis spinosa L.) is a xerophytic shrub with a remarkable adaptability to harsh environments. This plant species is of great interest for its medicinal/pharmacological properties and its culinary uses. Its phytochemical importance relies on many bioactive components present in different organs and its cultivation can be of considerable economic value. Moreover, taxonomic identification of C. spinosa L. has been difficult due to its wide heterogeneity, and many authors fell into confusion due to the scarcity of genetic studies. The present review summarizes information concerning C. spinosa L. including agronomic performance, botanical description, taxonomical approaches, traditional pharmacological uses, phytochemical evaluation and genetic studies. This knowledge represents an important tool for further research studies and agronomic development on this indigenous species with respect to the emerging climatic change in the Eastern Mediterranean countries. Indeed, this world region is particularly under the threat of global warming and it appears necessary to rethink agricultural systems to adapt them to current and futures challenging environmental conditions. Capparis spinosa L. could be a part of this approach. So, this review presents a state of the art considering caper as a potential interesting crop under arid or semi-arid regions (such as Eastern Mediterranean countries) within the climate change context. The aim is to raise awareness in the scientific community (geneticists, physiologists, ecophysiologists, agronomists, …) about the caper strengths and interest to the development of this shrub as a crop.

Capparis spinosa L. in A Systematic Review: A Xerophilous Species of Multi Values and Promising Potentialities for Agrosystems under the Threat of Global Warming

PubMed Central

Chedraoui, Stephanie; Abi-Rizk, Alain; El-Beyrouthy, Marc; Chalak, Lamis; Ouaini, Naim; Rajjou, Loïc

2017-01-01

Caper (Capparis spinosa L.) is a xerophytic shrub with a remarkable adaptability to harsh environments. This plant species is of great interest for its medicinal/pharmacological properties and its culinary uses. Its phytochemical importance relies on many bioactive components present in different organs and its cultivation can be of considerable economic value. Moreover, taxonomic identification of C. spinosa L. has been difficult due to its wide heterogeneity, and many authors fell into confusion due to the scarcity of genetic studies. The present review summarizes information concerning C. spinosa L. including agronomic performance, botanical description, taxonomical approaches, traditional pharmacological uses, phytochemical evaluation and genetic studies. This knowledge represents an important tool for further research studies and agronomic development on this indigenous species with respect to the emerging climatic change in the Eastern Mediterranean countries. Indeed, this world region is particularly under the threat of global warming and it appears necessary to rethink agricultural systems to adapt them to current and futures challenging environmental conditions. Capparis spinosa L. could be a part of this approach. So, this review presents a state of the art considering caper as a potential interesting crop under arid or semi-arid regions (such as Eastern Mediterranean countries) within the climate change context. The aim is to raise awareness in the scientific community (geneticists, physiologists, ecophysiologists, agronomists, …) about the caper strengths and interest to the development of this shrub as a crop. PMID:29118777

Characterization of Capsicum species using anatomical and molecular data.

PubMed

Dias, G B; Gomes, V M; Moraes, T M S; Zottich, U P; Rabelo, G R; Carvalho, A O; Moulin, M; Gonçalves, L S A; Rodrigues, R; Da Cunha, M

2013-02-28

Capsicum species are frequently described in terms of genetic divergence, considering morphological, agronomic, and molecular databases. However, descriptions of genetic differences based on anatomical characters are rare. We examined the anatomy and the micromorphology of vegetative and reproductive organs of several Capsicum species. Four Capsicum accessions representing the species C. annuum var. annuum, C. baccatum var. pendulum, C. chinense, and C. frutescens were cultivated in a greenhouse; leaves, fruits and seeds were sampled and their organ structure analyzed by light and scanning electronic microscopy. Molecular accession characterization was made using ISSR markers. Polymorphism was observed among tector trichomes and also in fruit color and shape. High variability among accessions was detected by ISSR markers. Despite the species studied present a wide morphological and molecular variability that was not reflected by anatomical features.

Predicting diameters inside bark for 10 important hardwood species

Treesearch

Donald E. Hilt; Everette D. Rast; Herman J. Bailey

1983-01-01

General models for predicting DIB/DOB ratios up the stem, applicable over wide geographic areas, have been developed for 10 important hardwood species. Results indicate that the ratios either decrease or remain constant up the stem. Methods for adjusting the general models to local conditions are presented. The prediction models can be used in conjunction with optical...

Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia

PubMed Central

Kokashvili, Tamar; Whitehouse, Chris A.; Tskhvediani, Ana; Grim, Christopher J.; Elbakidze, Tinatin; Mitaishvili, Nino; Janelidze, Nino; Jaiani, Ekaterine; Haley, Bradd J.; Lashkhi, Nino; Huq, Anwar; Colwell, Rita R.; Tediashvili, Marina

2015-01-01

Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n = 657) and freshwater lakes around Tbilisi (n = 938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost 90% of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human-pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8, 37.8, and 21.4% of samples testing positive for Vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii), and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs. PMID:26528464

Understanding Arsenic Dynamics in Agronomic Systems to Predict and Prevent Uptake by Crop Plants

EPA Science Inventory

This review is on arsenic in agronomic systems, and covers processes that influence the entry of arsenic into the human food supply. The scope is from sources of arsenic (natural and anthropogenic) in soils, biogeochemical and rhizosphere processes that control arsenic speciatio...

Nordic-Baltic Student Teachers' Identification of and Interest in Plant and Animal Species: The Importance of Species Identification and Biodiversity for Sustainable Development

NASA Astrophysics Data System (ADS)

Palmberg, Irmeli; Berg, Ida; Jeronen, Eila; Kärkkäinen, Sirpa; Norrgård-Sillanpää, Pia; Persson, Christel; Vilkonis, Rytis; Yli-Panula, Eija

2015-10-01

Knowledge of species, interest in nature, and nature experiences are the factors that best promote interest in and understanding of environmental issues, biodiversity and sustainable life. The aim of this study is to investigate how well student teachers identify common local species, their interest in and ideas about species identification, and their perceptions of the importance of species identification and biodiversity for sustainable development. Totally 456 student teachers for primary schools were tested using an identification test and a questionnaire consisting of fixed and open questions. A combination of quantitative and qualitative methods was used to get a more holistic view of students' level of knowledge and their preferred learning methods. The student teachers' ability to identify very common species was low, and only 3 % were able to identify most of the tested species. Experiential learning outdoors was suggested by the majority of students as the most efficient learning method, followed by experiential learning indoors, project work and experimental learning. They looked upon the identification of plants and animals as `important' or `very important' for citizens today and for sustainable development. Likewise, they looked upon biodiversity as `important' or `very important' for sustainable development. Our conclusion is that teaching and learning methods for identification and knowledge of species and for education of biodiversity and sustainable development should always include experiential and project-based methods in authentic environments.

Detection of medically important Candida species by absolute quantitation real-time polymerase chain reaction.

PubMed

Than, Leslie Thian Lung; Chong, Pei Pei; Ng, Kee Peng; Seow, Heng Fong

2015-01-01

The number of invasive candidiasis cases has risen especially with an increase in the number of immunosuppressed and immunocom promised patients. The early detection of Candida species which is specific and sensitive is important in determining the correct administration of antifungal drugs to patients. This study aims to develop a method for the detection, identification and quantitation of medically important Candida species through quantitative polymerase chain reaction (qPCR). The isocitrate lyase (ICL) gene which is not found in mammals was chosen as the target gene of real-time PCR. Absolute quantitation of the gene copy number was achieved by constructing the plasmid containing the ICL gene which is used to generate standard curve. Twenty fungal species, two bacterial species and human DNA were tested to check the specificity of the detection method. All eight Candida species were successfully detected, identified and quantitated based on the ICL gene. A seven-log range of the gene copy number and a minimum detection limit of 10(3) copies were achieved. A one-tube absolute quantification real-time PCR that differentiates medically important Candida species via individual unique melting temperature was achieved. Analytical sensitivity and specificity were not compromised.

Automatic detection and agronomic characterization of olive groves using high-resolution imagery and LIDAR data

NASA Astrophysics Data System (ADS)

Caruso, T.; Rühl, J.; Sciortino, R.; Marra, F. P.; La Scalia, G.

2014-10-01

The Common Agricultural Policy of the European Union grants subsidies for olive production. Areas of intensified olive farming will be of major importance for the increasing demand for oil production of the next decades, and countries with a high ratio of intensively and super-intensively managed olive groves will be more competitive than others, since they are able to reduce production costs. It can be estimated that about 25-40% of the Sicilian oliviculture must be defined as "marginal". Modern olive cultivation systems, which permit the mechanization of pruning and harvest operations, are limited. Agronomists, landscape planners, policy decision-makers and other professionals have a growing need for accurate and cost-effective information on land use in general and agronomic parameters in the particular. The availability of high spatial resolution imagery has enabled researchers to propose analysis tools on agricultural parcel and tree level. In our study, we test the performance of WorldView-2 imagery relative to the detection of olive groves and the delineation of olive tree crowns, using an object-oriented approach of image classification in combined use with LIDAR data. We selected two sites, which differ in their environmental conditions and in their agronomic parameters of olive grove cultivation. The main advantage of the proposed methodology is the low necessary quantity of data input and its automatibility. However, it should be applied in other study areas to test if the good results of accuracy assessment can be confirmed. Data extracted by the proposed methodology can be used as input data for decision-making support systems for olive grove management.

Distribution of Phenolic Compounds and Antioxidative Activities of Rice Kernel and Their Relationships with Agronomic Practice

PubMed Central

Kesarwani, Amit; Chiang, Po-Yuan; Chen, Shih-Shiung

2014-01-01

The phenolic and antioxidant activity of ethanolic extract of two Japonica rice cultivars, Taikeng no. 16 (medium and slender grain) and Kaohsiung no. 139 (short and round grain), grown under organic and conventional farming were examined. Analyses shows that Kaohsiung no. 139 contains the highest amount of secondary metabolites and continuous farming can increase its production. Results also suggest that phenolic content under different agronomic practices, has not shown significant differences but organically grown rice has proven to be better in higher accumulation of other secondary metabolites (2,2-diphenyl-1-picrylhydrazyl (DPPH), flavonoid content, and ferrous chelating capacity). In nutshell, genetic traits and environment have significant effect on phenolic compounds and the least variation reported under agronomic practices. PMID:25506072

Invasive species and biofuels: evaluating the risks of perennial crop breeding using reed canarygrass as a case study

USDA-ARS?s Scientific Manuscript database

Breeding efforts will play a critical role in meeting the increasing demand for cellulosic bioenergy feedstocks. However, a major concern is the potential development of novel invasive species that result from breeder’s efforts to improve agronomic traits in perennial crops. We use reed canarygrass ...

Important LiDAR metrics for discriminating forest tree species in Central Europe

NASA Astrophysics Data System (ADS)

Shi, Yifang; Wang, Tiejun; Skidmore, Andrew K.; Heurich, Marco

2018-03-01

Numerous airborne LiDAR-derived metrics have been proposed for classifying tree species. Yet an in-depth ecological and biological understanding of the significance of these metrics for tree species mapping remains largely unexplored. In this paper, we evaluated the performance of 37 frequently used LiDAR metrics derived under leaf-on and leaf-off conditions, respectively, for discriminating six different tree species in a natural forest in Germany. We firstly assessed the correlation between these metrics. Then we applied a Random Forest algorithm to classify the tree species and evaluated the importance of the LiDAR metrics. Finally, we identified the most important LiDAR metrics and tested their robustness and transferability. Our results indicated that about 60% of LiDAR metrics were highly correlated to each other (|r| > 0.7). There was no statistically significant difference in tree species mapping accuracy between the use of leaf-on and leaf-off LiDAR metrics. However, combining leaf-on and leaf-off LiDAR metrics significantly increased the overall accuracy from 58.2% (leaf-on) and 62.0% (leaf-off) to 66.5% as well as the kappa coefficient from 0.47 (leaf-on) and 0.51 (leaf-off) to 0.58. Radiometric features, especially intensity related metrics, provided more consistent and significant contributions than geometric features for tree species discrimination. Specifically, the mean intensity of first-or-single returns as well as the mean value of echo width were identified as the most robust LiDAR metrics for tree species discrimination. These results indicate that metrics derived from airborne LiDAR data, especially radiometric metrics, can aid in discriminating tree species in a mixed temperate forest, and represent candidate metrics for tree species classification and monitoring in Central Europe.

Capturing pair-wise epistatic effects associated with three agronomic traits in barley.

PubMed

Xu, Yi; Wu, Yajun; Wu, Jixiang

2018-04-01

Genetic association mapping has been widely applied to determine genetic markers favorably associated with a trait of interest and provide information for marker-assisted selection. Many association mapping studies commonly focus on main effects due to intolerable computing intensity. This study aims to select several sets of DNA markers with potential epistasis to maximize genetic variations of some key agronomic traits in barley. By doing so, we integrated a MDR (multifactor dimensionality reduction) method with a forward variable selection approach. This integrated approach was used to determine single nucleotide polymorphism pairs with epistasis effects associated with three agronomic traits: heading date, plant height, and grain yield in barley from the barley Coordinated Agricultural Project. Our results showed that four, seven, and five SNP pairs accounted for 51.06, 45.66 and 40.42% for heading date, plant height, and grain yield, respectively with epistasis being considered, while corresponding contributions to these three traits were 45.32, 31.39, 31.31%, respectively without epistasis being included. The results suggested that epistasis model was more effective than non-epistasis model in this study and can be more preferred for other applications.

Agronomic Competencies: A Comparison of Their Use and Perceived Importance.

ERIC Educational Resources Information Center

Scanlon, D. C.; Pennock, R., Jr.

1987-01-01

Reported is a survey designed to assess the relationship between essential competencies as perceived by faculty, and job needs as perceived by graduates of the agronomy department at Pennyslvania State University. Results indicated that while various competencies were valued differently, raters did not disagree on what were important competencies.…

Germination and early plant development of ten plant species exposed to titanium dioxide and cerium oxide nanoparticles

EPA Science Inventory

Ten agronomic plant species were exposed to different concentrations of nano titanium dioxide (nTiO2) or nano cerium oxide (nCeO2) (0, 250, 500 and 1000 mg/L) to examine potential effects on germination and early seedling development. We modified a standard test protocol develop...

Microbial effects on the development of forensically important blow fly species.

PubMed

Crooks, Esther R; Bulling, Mark T; Barnes, Kate M

2016-09-01

Colonisation times and development rates of specific blow fly species are used to estimate the minimum Post Mortem Interval (mPMI). The presence or absence of bacteria on a corpse can potentially affect the development and survival of blow fly larvae. Therefore an understanding of microbial-insect interactions is important for improving the interpretation of mPMI estimations. In this study, the effect of two bacteria (Escherichia coli and Staphylococcus aureus) on the growth rate and survival of three forensically important blow fly species (Lucilia sericata, Calliphora vicina and Calliphora vomitoria) was investigated. Sterile larvae were raised in a controlled environment (16:8h day: night light cycle, 23:21°C day: night temperature cycle and a constant 35% relative humidity) on four artificial diets prepared with 100μl of 10(5) CFU bacterial solutions as follows: (1) E. coli, (2) S. aureus, (3) a 50:50 E. coli:S. aureus mix and (4) a sterile bacteria-free control diet. Daily measurements (length, width and weight) were taken from first instar larvae through to the emergence of adult flies. Survival rates were also determined at pupation and adult emergence. Results indicate that bacteria were not essential for the development of any of the blow fly species. However, larval growth rates were affected by bacterial diet, with effects differing between blow fly species. Peak larval weights also varied according to species-diet combination; C. vomitoria had the largest weight on E. coli and mixed diets, C. vicina had the largest weight on S. aureus diets, and treatment had no significant effect on the peak larval weight of L. sericata. These results indicate the potential for the bacteria that larvae are exposed to during development on a corpse to alter both developmental rates and larval weight in some blow fly species. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Brine shrimp bioassay: importance of correct taxonomic identification of Artemia (Anostraca) species.

PubMed

Ruebhart, David R; Cock, Ian E; Shaw, Glen R

2008-08-01

Despite the common use of the brine shrimp bioassay in toxicology, there is confusion in the literature regarding citation of the correct taxonomic identity of the Artemia species used. The genus Artemia, once thought to be represented by a single species Artemia salina, is now known to be composed of several bisexual species as well as parthenogenetic populations. Artemia franciscana is the best studied of the Artemia species and is considered to represent the vast majority of studies in which Artemia is used as an experimental test organism. We found that in studies referring to the use of A. salina, the zoogeography of the cyst harvest site indicated that the species used was actually A. franciscana. Those performing bioassays with Artemia need to exercise diligence in assigning correct species identification, as the identity of the test organism is an important parameter in assuring the validity of the results of the assay.

The 'PUCE CAFE' Project: the First 15K Coffee Microarray, a New Tool for Discovering Candidate Genes correlated to Agronomic and Quality Traits

PubMed Central

2011-01-01

Background Understanding the genetic elements that contribute to key aspects of coffee biology will have an impact on future agronomical improvements for this economically important tree. During the past years, EST collections were generated in Coffee, opening the possibility to create new tools for functional genomics. Results The "PUCE CAFE" Project, organized by the scientific consortium NESTLE/IRD/CIRAD, has developed an oligo-based microarray using 15,721 unigenes derived from published coffee EST sequences mostly obtained from different stages of fruit development and leaves in Coffea Canephora (Robusta). Hybridizations for two independent experiments served to compare global gene expression profiles in three types of tissue matter (mature beans, leaves and flowers) in C. canephora as well as in the leaves of three different coffee species (C. canephora, C. eugenoides and C. arabica). Microarray construction, statistical analyses and validation by Q-PCR analysis are presented in this study. Conclusion We have generated the first 15 K coffee array during this PUCE CAFE project, granted by Génoplante (the French consortium for plant genomics). This new tool will help study functional genomics in a wide range of experiments on various plant tissues, such as analyzing bean maturation or resistance to pathogens or drought. Furthermore, the use of this array has proven to be valid in different coffee species (diploid or tetraploid), drastically enlarging its impact for high-throughput gene expression in the community of coffee research. PMID:21208403

The 'PUCE CAFE' Project: the first 15K coffee microarray, a new tool for discovering candidate genes correlated to agronomic and quality traits.

PubMed

Privat, Isabelle; Bardil, Amélie; Gomez, Aureliano Bombarely; Severac, Dany; Dantec, Christelle; Fuentes, Ivanna; Mueller, Lukas; Joët, Thierry; Pot, David; Foucrier, Séverine; Dussert, Stéphane; Leroy, Thierry; Journot, Laurent; de Kochko, Alexandre; Campa, Claudine; Combes, Marie-Christine; Lashermes, Philippe; Bertrand, Benoit

2011-01-05

Understanding the genetic elements that contribute to key aspects of coffee biology will have an impact on future agronomical improvements for this economically important tree. During the past years, EST collections were generated in Coffee, opening the possibility to create new tools for functional genomics. The "PUCE CAFE" Project, organized by the scientific consortium NESTLE/IRD/CIRAD, has developed an oligo-based microarray using 15,721 unigenes derived from published coffee EST sequences mostly obtained from different stages of fruit development and leaves in Coffea Canephora (Robusta). Hybridizations for two independent experiments served to compare global gene expression profiles in three types of tissue matter (mature beans, leaves and flowers) in C. canephora as well as in the leaves of three different coffee species (C. canephora, C. eugenoides and C. arabica). Microarray construction, statistical analyses and validation by Q-PCR analysis are presented in this study. We have generated the first 15 K coffee array during this PUCE CAFE project, granted by Génoplante (the French consortium for plant genomics). This new tool will help study functional genomics in a wide range of experiments on various plant tissues, such as analyzing bean maturation or resistance to pathogens or drought. Furthermore, the use of this array has proven to be valid in different coffee species (diploid or tetraploid), drastically enlarging its impact for high-throughput gene expression in the community of coffee research.

Propagation Techniques and Agronomic Requirements for the Cultivation of Barbados Aloe (Aloe vera (L.) Burm. F.)—A Review

PubMed Central

Cristiano, Giuseppe; Murillo-Amador, Bernardo; De Lucia, Barbara

2016-01-01

Barbados aloe (Aloe vera (L.) Burm. F.) has traditionally been used for healing in natural medicine. However, aloe is now attracting great interest in the global market due to its bioactive chemicals which are extracted from the leaves and used in industrial preparations for pharmaceutical, cosmetic, and food products. Aloe originated from tropical and sub-tropical Africa, but it is also now cultivated in warm climatic areas of Asia, Europe, and America. In this review, the most important factors affecting aloe production are described. We focus on propagation techniques, sustainable agronomic practices and efficient post harvesting and processing systems. PMID:27721816

Honeybees Increase Fruit Set in Native Plant Species Important for Wildlife Conservation

NASA Astrophysics Data System (ADS)

Cayuela, Luis; Ruiz-Arriaga, Sarah; Ozers, Christian P.

2011-11-01

Honeybee colonies are declining in some parts of the world. This may have important consequences for the pollination of crops and native plant species. In Spain, as in other parts of Europe, land abandonment has led to a decrease in the number of non professional beekeepers, which aggravates the problem of honeybee decline as a result of bee diseases In this study, we investigated the effects of honeybees on the pollination of three native plant species in northern Spain, namely wildcherry Prunus avium L., hawthorn Crataegus monogyna Jacq., and bilberry Vaccinium myrtillus L. We quantified fruit set of individuals from the target species along transects established from an apiary outwards. Half the samples were bagged in a nylon mesh to avoid insect pollination. Mixed-effects models were used to test the effect of distance to the apiary on fruit set in non-bagged samples. The results showed a negative significant effect of distance from the apiary on fruit set for hawthorn and bilberry, but no significant effects were detected for wildcherry. This suggests that the use of honeybees under traditional farming practices might be a good instrument to increase fruit production of some native plants. This may have important consequences for wildlife conservation, since fruits, and bilberries in particular, constitute an important feeding resource for endangered species, such as the brown bear Ursus arctos L. or the capercaillie Tetrao urogallus cantabricus L.

Honeybees increase fruit set in native plant species important for wildlife conservation.

PubMed

Cayuela, Luis; Ruiz-Arriaga, Sarah; Ozers, Christian P

2011-11-01

Honeybee colonies are declining in some parts of the world. This may have important consequences for the pollination of crops and native plant species. In Spain, as in other parts of Europe, land abandonment has led to a decrease in the number of non professional beekeepers, which aggravates the problem of honeybee decline as a result of bee diseases In this study, we investigated the effects of honeybees on the pollination of three native plant species in northern Spain, namely wildcherry Prunus avium L., hawthorn Crataegus monogyna Jacq., and bilberry Vaccinium myrtillus L. We quantified fruit set of individuals from the target species along transects established from an apiary outwards. Half the samples were bagged in a nylon mesh to avoid insect pollination. Mixed-effects models were used to test the effect of distance to the apiary on fruit set in non-bagged samples. The results showed a negative significant effect of distance from the apiary on fruit set for hawthorn and bilberry, but no significant effects were detected for wild cherry. This suggests that the use of honeybees under traditional farming practices might be a good instrument to increase fruit production of some native plants. This may have important consequences for wildlife conservation, since fruits, and bilberries in particular, constitute an important feeding resource for endangered species, such as the brown bear Ursus arctos L. or the capercaillie Tetrao urogallus cantabricus L.

NON-INDIGENOUS SPECIES: IMPORTANT BIOLOGICAL STRESSORS

EPA Science Inventory

A model for predicting where certain species will invade next is being developed and tested in cooperation with researchers at the University of Kansas. Human activities have increased the wholesale movement, either accidental or deliberate, of many species of animals and plants ...

Patterns of species richness and diversity of insects associated with cucurbit fruits in the southern part of Cameroon.

PubMed

Mokam, Didi Gaëlle; Djiéto-Lordon, Champlain; Bilong Bilong, Charles-Félix

2014-01-01

Patterns of species diversity and community structure of insects associated with fruits of domesticated cucurbits were investigated from January 2009 to 2011 in three localities from two agroecological zones in the southern part of Cameroon. Rarefaction curves combined with nonparametric estimators of species richness were used to extrapolate species richness beyond our own data. Sampling efforts of over 92% were reached in each of the three study localities. Data collected revealed a total of 66 insect morphospecies belonging to 37 families and five orders, identified from a set of 57,510 insects. The orders Diptera (especially Tephritidae and Lonchaeidae) and Hymenoptera (mainly Braconidae and Eulophidae) were the most important, in terms of both abundance and species richness on the one hand, and effects on agronomic performance on the other. Values for both the species diversity (Shannon and Simpson) and the species richness indices (Margalef and Berger-Parker) calculated showed that the insect communities were species-rich but dominated, all to a similar extent, by five main species (including four fruit fly species and one parasitoid). Species abundance distributions in these communities ranged from the Zipf-Mandelbrot to Mandelbrot models. The communities are structured as tritrophic networks, including cucurbit fruits, fruit-feeding species (fruit flies) and carnivorous species (parasitoids). Within the guild of the parasitoids, about 30% of species, despite their low abundance, may potentially be of use in biological control of important pests. Our field data contribute in important ways to basic knowledge of biodiversity patterns in agrosystems and constitute baseline data for the planned implementation of biological control in Integrated Pest Management. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

Molecular, Genetic and Agronomic Approaches to Utilizing Pulses as Cover Crops and Green Manure into Cropping Systems

PubMed Central

Tani, Eleni; Abraham, Eleni; Chachalis, Demosthenis; Travlos, Ilias

2017-01-01

Cover crops constitute one of the most promising agronomic practices towards a more sustainable agriculture. Their beneficial effects on main crops, soil and environment are many and various, while risks and disadvantages may also appear. Several legumes show a high potential but further research is required in order to suggest the optimal legume cover crops for each case in terms of their productivity and ability to suppress weeds. The additional cost associated with cover crops should also be addressed and in this context the use of grain legumes such as cowpea, faba bean and pea could be of high interest. Some of the aspects of these grain legumes as far as their use as cover crops, their genetic diversity and their breeding using conventional and molecular approaches are discussed in the present review. The specific species seem to have a high potential for use as cover crops, especially if their noticeable genetic diversity is exploited and their breeding focuses on several desirable traits. PMID:28587254

Variation of agronomic traits of ravenna grass and its potential as a biomass crop

USDA-ARS?s Scientific Manuscript database

Ravenna grass (Tripidium ravennae) is a tall robust bunchgrass with potential as an energy crop. The aim was to investigate the variation of agronomic traits of Ravenna grass. Univariate analyses of traits were conducted on 95 plants from 2013 to 2017. The traits were: biomass yield per plant, C, N,...

Agronomic assessment of pyrolysed food waste digestate for sandy soil management.

PubMed

Opatokun, Suraj Adebayo; Yousef, Lina F; Strezov, Vladimir

2017-02-01

The digestate (DFW) of an industrial food waste treatment plant was pyrolysed for production of biochar for its direct application as bio-fertilizer or soil enhancer. Nutrient dynamics and agronomic viability of the pyrolysed food waste digestate (PyD) produced at different temperatures were evaluated using germination index (GI), water retention/availability and mineral sorption as indicators when applied on arid soil. The pyrolysis was found to enrich P, K and other micronutrients in the biochar at an average enrichment factor of 0.87. All PyD produced at different temperatures indicated significantly low phytotoxicity with GI range of 106-168% and an average water retention capacity of 40.2%. Differential thermogravimetric (DTG) thermographs delineated the stability of the food waste digestate pyrolysed at 500 °C (PyD500) against the degradation of the digestate food waste despite the latter poor nutrient sorption potential. Plant available water in soil is 40% when treated with 100 g of digestate per kg soil, whereas PyD500 treated soil indicated minimal effect on plant available water, even with high application rates. However, the positive effects of PyD on GI and the observed enrichment in plant macro and micronutrients suggest potential agronomic benefits for PyD use, in addition to the benefits from energy production from DFW during the pyrolysis process. Copyright © 2016 Elsevier Ltd. All rights reserved.

Two new Cytospora species, Cytospora vinacea sp. nov. and Cytospora viticola sp. nov., from declining vineyards in eastern North America

USDA-ARS?s Scientific Manuscript database

Cytospora species are ubiquitous pathogens of woody plants, causing branch dieback and wood cankers in numerous perennial hosts, including agronomic crops (e.g., Prunus), timber trees (e.g., Eucalyptus), and riparian hosts (e.g., Salix). Cytospora chrysosperma, C. cincta, and C. leucostoma have been...

Agronomic performance of insect-protected and herbicide-tolerant MON 89034 × TC1507 × NK603 × DAS-40278-9 corn is equivalent to that of conventional corn.

PubMed

de Cerqueira, Denise T Rezende; Schafer, Ariane C; Fast, Brandon J; Herman, Rod A

2017-07-03

Agronomic characteristics of genetically modified (GM) MON 89034 × TC1507 × NK603 × DAS-40278-9 (PowerCore™ Enlist™), MON 89034 × TC1507 × NK603 (PowerCore™), and DAS-40278-9 (Enlist™) corn, a non-GM near-isogenic hybrid, and 2 commercial non-GM hybrids were assessed in a field study to determine if the agronomic performance of the GM corn hybrids is equivalent to that of non-transgenic hybrid corn. The MON 89034 × TC1507 × NK603 × DAS-40278-9 hybrid corn was developed through stacking of 4 individual transgenic events, MON 89034, TC1507, NK603, and DAS-40278-9 by traditional breeding and contains the cry1A.105 and cry2Ab2 (MON 89034), cry1F and pat (TC1507), cp4 epsps (NK603) and aad-1 (DAS-40278-9) transgenes. These transgenes encode the proteins Cry1A.105, Cry2Ab2, and Cry1F, which confer insect resistance, PAT, CP4 EPSPS, and AAD-1, which confer herbicide tolerance. The following agronomic characteristics were assessed in the study: initial and final stand count, seedling vigor, time to silk, time to pollen shed, pollen viability, plant height, ear height, stalk lodging, root lodging, days to maturity, stay green, disease incidence, insect damage, herbicide injury, and yield. The agronomic assessment was conducted in 2 regions of Brazil (Indianopolis-MG; Cravinhos-SP). The agronomic attributes for all GM entries were statistically indistinguishable from the non-GM near-isogenic hybrid. In addition, most of the agronomic assessments fell within the range of the commercial varieties included in the study. Taken together, MON 89034 × TC1507 × NK603 × DAS-40278, MON 89034 × TC1507 × NK603, and DAS-40278-9 were found to be agronomically equivalent to non-GM corn.

Investigation of the effect of genotype and agronomic conditions on metabolomic profiles of selected strawberry cultivars with different sensitivity to environmental stress.

PubMed

Akhatou, Ikram; González-Domínguez, Raúl; Fernández-Recamales, Ángeles

2016-04-01

Strawberry is one of the most economically important and widely cultivated fruit crops across the world, so that there is a growing need to develop new analytical methodologies for the authentication of variety and origin, as well as the assessment of agricultural and processing practices. In this work, an untargeted metabolomic strategy based on gas chromatography mass spectrometry (GC-MS) combined with multivariate statistical techniques was used for the first time to characterize the primary metabolome of different strawberry cultivars and to study metabolite alterations in response to multiple agronomic conditions. For this purpose, we investigated three varieties of strawberries with different sensitivity to environmental stress (Camarosa, Festival and Palomar), cultivated in soilless systems using various electrical conductivities, types of coverage and substrates. Metabolomic analysis revealed significant alterations in primary metabolites between the three strawberry cultivars grown under different crop conditions, including sugars (fructose, glucose), organic acids (malic acid, citric acid) and amino acids (alanine, threonine, aspartic acid), among others. Therefore, it could be concluded that GC-MS based metabolomics is a suitable tool to differentiate strawberry cultivars and characterize metabolomic changes associated with environmental and agronomic conditions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

A high-density genetic map and QTL analysis of agronomic traits in foxtail millet [Setaria italica (L.) P. Beauv.] using RAD-seq.

PubMed

Wang, Jun; Wang, Zhilan; Du, Xiaofen; Yang, Huiqing; Han, Fang; Han, Yuanhuai; Yuan, Feng; Zhang, Linyi; Peng, Shuzhong; Guo, Erhu

2017-01-01

Foxtail millet (Setaria italica), a very important grain crop in China, has become a new model plant for cereal crops and biofuel grasses. Although its reference genome sequence was released recently, quantitative trait loci (QTLs) controlling complex agronomic traits remains limited. The development of massively parallel genotyping methods and next-generation sequencing technologies provides an excellent opportunity for developing single-nucleotide polymorphisms (SNPs) for linkage map construction and QTL analysis of complex quantitative traits. In this study, a high-throughput and cost-effective RAD-seq approach was employed to generate a high-density genetic map for foxtail millet. A total of 2,668,587 SNP loci were detected according to the reference genome sequence; meanwhile, 9,968 SNP markers were used to genotype 124 F2 progenies derived from the cross between Hongmiaozhangu and Changnong35; a high-density genetic map spanning 1648.8 cM, with an average distance of 0.17 cM between adjacent markers was constructed; 11 major QTLs for eight agronomic traits were identified; five co-dominant DNA markers were developed. These findings will be of value for the identification of candidate genes and marker-assisted selection in foxtail millet.

A high-density genetic map and QTL analysis of agronomic traits in foxtail millet [Setaria italica (L.) P. Beauv.] using RAD-seq

PubMed Central

Wang, Zhilan; Du, Xiaofen; Yang, Huiqing; Han, Fang; Han, Yuanhuai; Yuan, Feng; Zhang, Linyi; Peng, Shuzhong; Guo, Erhu

2017-01-01

Foxtail millet (Setaria italica), a very important grain crop in China, has become a new model plant for cereal crops and biofuel grasses. Although its reference genome sequence was released recently, quantitative trait loci (QTLs) controlling complex agronomic traits remains limited. The development of massively parallel genotyping methods and next-generation sequencing technologies provides an excellent opportunity for developing single-nucleotide polymorphisms (SNPs) for linkage map construction and QTL analysis of complex quantitative traits. In this study, a high-throughput and cost-effective RAD-seq approach was employed to generate a high-density genetic map for foxtail millet. A total of 2,668,587 SNP loci were detected according to the reference genome sequence; meanwhile, 9,968 SNP markers were used to genotype 124 F2 progenies derived from the cross between Hongmiaozhangu and Changnong35; a high-density genetic map spanning 1648.8 cM, with an average distance of 0.17 cM between adjacent markers was constructed; 11 major QTLs for eight agronomic traits were identified; five co-dominant DNA markers were developed. These findings will be of value for the identification of candidate genes and marker-assisted selection in foxtail millet. PMID:28644843

Germination and early plant development of 10 plant species exposed to Nano TiO2 and CeO2

EPA Science Inventory

Ten agronomic plant species were exposed to different concentrations of nano-TiO2 or CeO2 (0, 250, 500 and 1000 ug/l) and followed to examine effects on germination and early seedling development. For TiO2, cabbage showed increased and corn decreased percent germination, while ...

Characterization of Cytospora isolates from wood cankers of declining grapevine in North America, with the descriptions of two new Cytospora species

USDA-ARS?s Scientific Manuscript database

Cytospora species are ubiquitous pathogens of woody plants, causing dieback and wood cankers in numerous perennial hosts, including agronomic crops (e.g., Prunus), timber trees (e.g., Eucalyptus), and riparian hosts (e.g., Salix). Cytospora chrysosperma, C. cincta, and C. leucostoma have been report...

Complementary effects of species and genetic diversity on productivity and stability of sown grasslands.

PubMed

Prieto, Iván; Violle, Cyrille; Barre, Philippe; Durand, Jean-Louis; Ghesquiere, Marc; Litrico, Isabelle

2015-03-30

Plant species diversity regulates the productivity(1-3) and stability(2,4) of natural ecosystems, along with their resilience to disturbance(5,6). The influence of species diversity on the productivity of agronomic systems is less clear(7-10). Plant genetic diversity is also suspected to influence ecosystem function(3,11-14), although empirical evidence is scarce. Given the large range of genotypes that can be generated per species through artificial selection, genetic diversity is a potentially important leverage of productivity in cultivated systems. Here we assess the effect of species and genetic diversity on the production and sustainable supply of livestock fodder in sown grasslands, comprising single and multispecies assemblages characterized by different levels of genetic diversity, exposed to drought and non-drought conditions. Multispecies assemblages proved more productive than monocultures when subject to drought, regardless of the number of genotypes per species present. Conversely, the temporal stability of production increased only with the number of genotypes present under both drought and non-drought conditions, and was unaffected by the number of species. We conclude that taxonomic and genetic diversity can play complementary roles when it comes to optimizing livestock fodder production in managed grasslands, and suggest that both levels of diversity should be considered in plant breeding programmes designed to boost the productivity and resilience of managed grasslands in the face of increasing environmental hazards.

Importance of riparian remnants for frog species diversity in a highly fragmented rainforest.

PubMed

Rodríguez-Mendoza, Clara; Pineda, Eduardo

2010-12-23

Tropical forests undergo continuous transformation to other land uses, resulting in landscapes typified by forest fragments surrounded by anthropogenic habitats. Small forest fragments, specifically strip-shaped remnants flanking streams (referred to as riparian remnants), can be particularly important for the maintenance and conservation of biodiversity within highly fragmented forests. We compared frog species diversity between riparian remnants, other forest fragments and cattle pastures in a tropical landscape in Los Tuxtlas, Mexico. We found similar species richness in the three habitats studied and a similar assemblage structure between riparian remnants and forest fragments, although species composition differed by 50 per cent. Frog abundance was halved in riparian remnants compared with forest fragments, but was twice that found in pastures. Our results suggest that riparian remnants play an important role in maintaining a portion of frog species diversity in a highly fragmented forest, particularly during environmentally stressful (hot and dry) periods. In this regard, however, the role of riparian remnants is complementary, rather than substitutive, with respect to the function of other forest fragments within the fragmented forest.

Spectral-agronomic relationships of corn, soybean and wheat canopies

NASA Technical Reports Server (NTRS)

Bauer, M. E. (Principal Investigator); Daughtry, C. S. T.; Vanderbilt, V. C.

1981-01-01

During the past six years several thousand reflectance spectra of corn, soybean, and wheat canopies were acquired and analyzed. The relationships of biophysical variables, including leaf area index, percent soil cover, chlorophyll and water content, to the visible and infrared reflectance of canopies are described. The effects on reflectance of cultural, environmental, and stress factors such as planting data, seeding rate, row spacing, cultivar, soil type and nitrogen fertilization are also examined. The conclusions are that several key agronomic variables including leaf area index, development stage and degree of stress are strongly related to spectral reflectance and that it should be possible to estimate these descriptions of crop condition from satellite acquired multispectral data.

Study on Analysis of Variance on the indigenous wild and cultivated rice species of Manipur Valley

NASA Astrophysics Data System (ADS)

Medhabati, K.; Rohinikumar, M.; Rajiv Das, K.; Henary, Ch.; Dikash, Th.

2012-10-01

The analysis of variance revealed considerable variation among the cultivars and the wild species for yield and other quantitative characters in both the years of investigation. The highly significant differences among the cultivars in year wise and pooled analysis of variance for all the 12 characters reveal that there are enough genetic variabilities for all the characters studied. The existence of genetic variability is of paramount importance for starting a judicious plant breeding programme. Since introduced high yielding rice cultivars usually do not perform well. Improvement of indigenous cultivars is a clear choice for increase of rice production. The genetic variability of 37 rice germplasms in 12 agronomic characters estimated in the present study can be used in breeding programme

A highly concentrated diet increases biogas production and the agronomic value of young bull's manure.

PubMed

Mendonça Costa, Mônica Sarolli Silva de; Lucas, Jorge de; Mendonça Costa, Luiz Antonio de; Orrico, Ana Carolina Amorim

2016-02-01

The increasing demand for animal protein has driven significant changes in cattle breeding systems, mainly in feedlots, with the use of young bulls fed on diets richer in concentrate (C) than in forage (F). These changes are likely to affect animal manure, demanding re-evaluation of the biogas production per kg of TS and VS added, as well as of its agronomic value as a biofertilizer, after anaerobic digestion. Here, we determined the biogas production and agronomic value (i.e., the macronutrient concentration in the final biofertilizer) of the manure of young bulls fed on diets with more (80% C+20% F; 'HighC' diet) or less (65% C+35% F; 'LowC' diet) concentrate, evaluating the effects of temperature (25, 35, and 40°C) and the use of an inoculum, during anaerobic digestion. A total of 24 benchtop reactors were used, operating in a semi-continuous system, with a 40-day hydraulic retention time (HRT). The manure from animals given the HighC diet had the greatest potential for biogas production, when digested with the use of an inoculum and at 35 or 40°C (0.6326 and 0.6207m(3)biogas/kg volatile solids, or VS, respectively). We observed the highest levels of the macronutrients N, P, and K in the biofertilizer from the manure of animals given HighC. Our results show that the manure of young bulls achieves its highest potential for biogas production and agronomic value when animals are fed diets richer in concentrate, and that biogas production increases if digestion is performed at higher temperatures, and with the use of an inoculum. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of oil content and fatty acid composition variability in two economically important Hibiscus species.

USDA-ARS?s Scientific Manuscript database

The Hibiscus genus encompasses more than 300 species, but kenaf (H. cannabinus L.) and roselle (H. sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterc...

Projected climate and agronomic implications for corn production in the Northeastern United States.

PubMed

Prasad, Rishi; Gunn, Stephan Kpoti; Rotz, Clarence Alan; Karsten, Heather; Roth, Greg; Buda, Anthony; Stoner, Anne M K

2018-01-01

Corn has been a pillar of American agriculture for decades and continues to receive much attention from the scientific community for its potential to meet the food, feed and fuel needs of a growing human population in a changing climate. By midcentury, global temperature increase is expected to exceed 2°C where local effects on heat, cold and precipitation extremes will vary. The Northeast United States is a major dairy producer, corn consumer, and is cited as the fastest warming region in the contiguous U.S. It is important to understand how key agronomic climate variables affect corn growth and development so that adaptation strategies can be tailored to local climate changes. We analyzed potential local effects of climate change on corn growth and development at three major dairy locations in the Northeast (Syracuse, New York; State College, Pennsylvania and Landisville, Pennsylvania) using downscaled projected climate data (2000-2100) from nine Global Climate Models under two emission pathways (Representative Concentration Pathways (RCP) 4.5 and 8.5). Our analysis indicates that corn near the end of the 21st century will experience fewer spring and fall freezes, faster rate of growing degree day accumulation with a reduction in time required to reach maturity, greater frequencies of daily high temperature ≥35°C during key growth stages such as silking-anthesis and greater water deficit during reproductive (R1-R6) stages. These agronomic anomalies differ between the three locations, illustrating varying impacts of climate change in the more northern regions vs. the southern regions of the Northeast. Management strategies such as shifting the planting dates based on last spring freeze and irrigation during the greatest water deficit stages (R1-R6) will partially offset the projected increase in heat and drought stress. Future research should focus on understanding the effects of global warming at local levels and determining adaptation strategies that meet

Worldwide Dissemination of Radopholus similis and Its Importance in Crop Production

PubMed Central

O'Bannon, J. H.

1977-01-01

The burrowing nematode, Radopholus similis, attacks agronomic and horticultural crops and many weeds, and is reported to reproduce on more than 250 plant species. Two races of R. similis are recognized. Although one race attacks citrus and the other race does not, they are morphologically similar. At present, the citrus race is found attacking citrus only in Florida, U.S.A., but it is known to infect more than 250 species and varieties of noncitrus plants. Although it has many hosts, R. similis is probably most widely distributed on banana and is found worldwide. Although best known as a pest of Piper nigrum, Musa spp., and Citrus spp., it also attacks many crops that are important in world commerce and in subsistence-type agriculture, a factor which makes it a significant agricultural pest. Worldwide dissemination occurs primarily when parasitized plants are moved into areas where the pest could adapt. Yield losses of 12.5 tons/ha in bananas have been reported from R. similis infection. Infections suppress orange and grapefruit yields as much as 70-80%. Because of the severity of R. similis damage (particularly to banana and citrus), extensive control programs have been developed. Prevention, cultural practices, resistant varieties, and chemical pesticides interact to reduce losses. PMID:19305565

Greenhouse gas emissions and energy efficiencies for soybeans and maize cultivated in different agronomic zones: A case study of Argentina.

PubMed

Arrieta, E M; Cuchietti, A; Cabrol, D; González, A D

2018-06-01

Of all human activities, agriculture has one of the highest environmental impacts, particularly related to Greenhouse Gas (GHG) emissions, energy use and land use change. Soybean and maize are two of the most commercialized agricultural commodities worldwide. Argentina contributes significantly to this trade, being the third major producer of soybeans, the first exporter of soymeal and soybean oil, and the third exporter of maize. Despite the economic importance of these crops and the products derived, there are very few studies regarding GHG emissions, energy use and efficiencies associated to Argentinean soybean and maize production. Therefore, the aim of this work is to determine the carbon and energy footprint, as well as the carbon and energy efficiencies, of soybeans and maize produced in Argentina, by analyzing 18 agronomic zones covering an agricultural area of 1.53millionkm 2 . Our results show that, for both crops, the GHG and energy efficiencies at the Pampean region were significantly higher than those at the extra-Pampean region. The national average for production of soybeans in Argentina results in 6.06ton/ton CO 2 -eq emitted to the atmosphere, while 0.887ton of soybean were produced per GJ of energy used; and for maize 5.01ton/ton CO 2 -eq emitted to the atmosphere and 0.740ton of maize were produced per each GJ of energy used. We found that the large differences on yields, GHGs and energy efficiencies between agronomic regions for soybean and maize crop production are mainly driven by climate, particularly mean annual precipitation. This study contributes for the first time to understand the carbon and energy footprint of soybean and maize production throughout several agronomic zones in Argentina. The significant differences found in the productive efficiencies questions on the environmental viability of expanding the agricultural frontier to less suitable lands for crop production. Copyright © 2017 Elsevier B.V. All rights reserved.

9 CFR 93.911 - Ports designated for the importation of live VHS-regulated fish species.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of live VHS-regulated fish species. 93.911 Section 93.911 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Vhs-Regulated Fish Species § 93.911 Ports designated for the...

9 CFR 93.911 - Ports designated for the importation of live VHS-regulated fish species.

Code of Federal Regulations, 2014 CFR

2014-01-01

... of live VHS-regulated fish species. 93.911 Section 93.911 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Vhs-Regulated Fish Species § 93.911 Ports designated for the...

9 CFR 93.911 - Ports designated for the importation of live VHS-regulated fish species.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of live VHS-regulated fish species. 93.911 Section 93.911 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Vhs-Regulated Fish Species § 93.911 Ports designated for the...

9 CFR 93.911 - Ports designated for the importation of live VHS-regulated fish species.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of live VHS-regulated fish species. 93.911 Section 93.911 Animals and Animal Products ANIMAL AND... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Vhs-Regulated Fish Species § 93.911 Ports designated for the...

The Importance of the Regional Species Pool, Ecological Species Traits and Local Habitat Conditions for the Colonization of Restored River Reaches by Fish

PubMed Central

Stoll, Stefan; Kail, Jochem; Lorenz, Armin W.; Sundermann, Andrea; Haase, Peter

2014-01-01

It is commonly assumed that the colonization of restored river reaches by fish depends on the regional species pools; however, quantifications of the relationship between the composition of the regional species pool and restoration outcome are lacking. We analyzed data from 18 German river restoration projects and adjacent river reaches constituting the regional species pools of the restored reaches. We found that the ability of statistical models to describe the fish assemblages established in the restored reaches was greater when these models were based on ‘biotic’ variables relating to the regional species pool and the ecological traits of species rather than on ‘abiotic’ variables relating to the hydromorphological habitat structure of the restored habitats and descriptors of the restoration projects. For species presence in restored reaches, ‘biotic’ variables explained 34% of variability, with the occurrence rate of a species in the regional species pool being the most important variable, while ’abiotic’ variables explained only the negligible amount of 2% of variability. For fish density in restored reaches, about twice the amount of variability was explained by ‘biotic’ (38%) compared to ‘abiotic’ (21%) variables, with species density in the regional species pool being most important. These results indicate that the colonization of restored river reaches by fish is largely determined by the assemblages in the surrounding species pool. Knowledge of species presence and abundance in the regional species pool can be used to estimate the likelihood of fish species becoming established in restored reaches. PMID:24404187

Long-term on-farm participatory maize breeding by stratified mass selection retains molecular diversity while improving agronomic performance.

PubMed

Alves, Mara Lisa; Belo, Maria; Carbas, Bruna; Brites, Cláudia; Paulo, Manuel; Mendes-Moreira, Pedro; Brites, Carla; Bronze, Maria do Rosário; Šatović, Zlatko; Vaz Patto, Maria Carlota

2018-02-01

Modern maize breeding programs gave rise to genetically uniform varieties that can affect maize's capacity to cope with increasing climate unpredictability. Maize populations, genetically more heterogeneous, can evolve and better adapt to a broader range of edaphic-climatic conditions. These populations usually suffer from low yields; it is therefore desirable to improve their agronomic performance while maintaining their valuable diversity levels. With this objective, a long-term participatory breeding/on-farm conservation program was established in Portugal. In this program, maize populations were subject to stratified mass selection. This work aimed to estimate the effect of on-farm stratified mass selection on the agronomic performance, quality, and molecular diversity of two historical maize populations. Multilocation field trials, comparing the initial populations with the derived selection cycles, showed that this selection methodology led to agronomic improvement for one of the populations. The molecular diversity analysis, using microsatellites, revealed that overall genetic diversity in both populations was maintained throughout selection. The comparison of quality parameters between the initial populations and the derived selection cycles was made using kernel from a common-garden experiment. This analysis showed that the majority of the quality traits evaluated progressed erratically over time. In conclusion, this breeding approach, through simple and low-cost methodologies, proved to be an alternative strategy for genetic resources' on-farm conservation.

A novel way to establish fertilization recommendations based on agronomic efficiency and a sustainable yield index for rice crops.

PubMed

Liu, Chuang; Liu, Yi; Li, Zhiguo; Zhang, Guoshi; Chen, Fang

2017-04-24

A simpler approach for establishing fertilizer recommendations for major crops is urgently required to improve the application efficiency of commercial fertilizers in China. To address this need, we developed a method based on field data drawn from the China Program of the International Plant Nutrition Institute (IPNI) rice experiments and investigations carried out in southeastern China during 2001 to 2012. Our results show that, using agronomic efficiencies and a sustainable yield index (SYI), this new method for establishing fertilizer recommendations robustly estimated the mean rice yield (7.6 t/ha) and mean nutrient supply capacities (186, 60, and 96 kg/ha of N, P 2 O 5 , and K 2 O, respectively) of fertilizers in the study region. In addition, there were significant differences in rice yield response, economic cost/benefit ratio, and nutrient-use efficiencies associated with agronomic efficiencies ranked as high, medium and low. Thus, ranking agronomic efficiency could strengthen linear models relating rice yields and SYI. Our results also indicate that the new method provides better recommendations in terms of rice yield, SYI, and profitability than previous methods. Hence, we believe it is an effective approach for improving recommended applications of commercial fertilizers to rice (and potentially other crops).

Molecular characterization of Fasciola species isolated from imported sheep in Taif region (Saudi Arabia).

PubMed

Shalaby, I; Gherbawy, Y; Banaja, A

2013-03-01

Accurate identification of Fasciola species, followed by biological and ecological characterization, is important with concern to the planning for field control. Because there are many variations in morphological characteristics, exact distinguishing of Fasciola species is usually difficult by simple traditional microscopic measurements and, therefore, the morphometric characterization may be insufficient for the species identification. Hence, the present work was proposed to collect 100 liver samples from 100 imported sheep from Sudan from slaughterhouses in Taif region. The samples were firstly examined macroscopically and microscopically to ensure the presence or absence of infection. The collected worms were subjected for RAPD-PCR analysis using different primers and ITS1 sequences for accurate identification. Using RAPD-PCR analysis, two primers were selected to amplify the DNA of each Fasciola. The results show that the amplification fragments were between 500 and 1500 bp and, the use of random genetic markers allowed to discriminate among the different collected species. Using Internal transcribed spacer region (ITS) sequencing, the imported sheep in Taif region consisted of 630 bps including complete ITS1, partial 18S and 5.8S and had 5 variable nucleotide positions. This is the first demonstration of the existence of both F. hepatica, F. gigantica and hybrid and/or introgressed populations of liver flukes bearing genetic material from both F. hepatica and F. gigantica in the imported sheep in Saudi Arabia by a genetic approach.

Patterns of among- and within-species variation in heterospecific pollen receipt: The importance of ecological generalization.

PubMed

Arceo-Gómez, Gerardo; Abdala-Roberts, Luis; Jankowiak, Anneka; Kohler, Clare; Meindl, George A; Navarro-Fernández, Carmen M; Parra-Tabla, Víctor; Ashman, Tia-Lynn; Alonso, Conchita

2016-03-01

Coflowering plants are at risk for receiving pollen from heterospecifics as well as conspecifics, yet evidence shows wide variation in the degree that heterospecific pollen transfer occurs. Evaluation of patterns and correlates of among- and within-species variation in heterospecific pollen (HP) receipt is key to understanding its importance for floral evolution and species coexistence; however, the rarity of deeply sampled multispecies comparisons has precluded such an evaluation. We evaluated patterns of among- and within-species variation in HP load size and diversity in 19 species across three distinct plant communities. We assessed the importance of phenotypic specialization (floral phenotype), ecological specialization (contemporary visitor assemblage), and conspecific flower density as determinants of among-species variation. We present hypotheses for different accrual patterns of HP within species based on the evenness and quality of floral visitors and evaluated these by characterizing the relationship between conspecific pollen (CP) and HP receipt. We found that within-species variation in HP receipt was greater than among-species and among-communities variation. Among species, ecological generalization emerged as the strongest driver of variation in HP receipt irrespective of phenotypic specialization. Within-species variation in HP load size and diversity was predicted most often from two CP-HP relationships (linear or exponentially decreasing), suggesting that two distinct types of plant-pollinator interactions prevail. Our results give important insights into the potential drivers of among- and within-species variation in HP receipt. They also highlight the value of explorations of patterns at the intraspecific level, which can ultimately shed light on plant-pollinator-mediated selection in diverse plant communities. © 2016 Botanical Society of America.

Integration of agronomic practices with herbicides for sustainable weed management in aerobic rice.

PubMed

Anwar, M P; Juraimi, A S; Mohamed, M T M; Uddin, M K; Samedani, B; Puteh, A; Man, Azmi

2013-01-01

Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point.

Integration of Agronomic Practices with Herbicides for Sustainable Weed Management in Aerobic Rice

PubMed Central

Anwar, M. P.; Juraimi, A. S.; Mohamed, M. T. M.; Uddin, M. K.; Samedani, B.; Puteh, A.; Man, Azmi

2013-01-01

Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point. PMID:24223513

Pollen Deposition Is More Important than Species Richness for Seed Set in Luffa Gourd.

PubMed

Ali, M; Saeed, S; Sajjad, A

2016-10-01

In the context of global biodiversity decline, it is imperative to understand the different aspects of bee communities for sustaining the vital ecosystem service of pollination. Bee species can be assigned to functional groups (average difference among species in functionally related traits) on the basis of complementarity (trait variations exhibited by individual organisms) in their behavior but is not yet known which functional group trait is most important for seed set. In this study, first, the functional groups of bees were made based on their five selected traits (pollen deposition, visitation rate, stay time, visiting time of the day, body size) and then related to the seed set of obligate cross-pollinated Luffa gourd (Luffa aegyptiaca). We found that bee diversity and abundance differed significantly among the studied plots, but only the bee species richness was positively related to the seed set. Functional group diversity in terms of pollen deposition explained even more of the variance in seed set (r 2  = 0.74) than did the species richness (r 2  = 0.53) making it the most important trait of bee species for predicting the crop reproductive success.

Standardization of a two-step real-time polymerase chain reaction based method for species-specific detection of medically important Aspergillus species.

PubMed

Das, P; Pandey, P; Harishankar, A; Chandy, M; Bhattacharya, S; Chakrabarti, A

2017-01-01

Standardization of Aspergillus polymerase chain reaction (PCR) poses two technical challenges (a) standardization of DNA extraction, (b) optimization of PCR against various medically important Aspergillus species. Many cases of aspergillosis go undiagnosed because of relative insensitivity of conventional diagnostic methods such as microscopy, culture or antigen detection. The present study is an attempt to standardize real-time PCR assay for rapid sensitive and specific detection of Aspergillus DNA in EDTA whole blood. Three nucleic acid extraction protocols were compared and a two-step real-time PCR assay was developed and validated following the recommendations of the European Aspergillus PCR Initiative in our setup. In the first PCR step (pan-Aspergillus PCR), the target was 28S rDNA gene, whereas in the second step, species specific PCR the targets were beta-tubulin (for Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus), gene and calmodulin gene (for Aspergillus niger). Species specific identification of four medically important Aspergillus species, namely, A. fumigatus, A. flavus, A. niger and A. terreus were achieved by this PCR. Specificity of the PCR was tested against 34 different DNA source including bacteria, virus, yeast, other Aspergillus sp., other fungal species and for human DNA and had no false-positive reactions. The analytical sensitivity of the PCR was found to be 102 CFU/ml. The present protocol of two-step real-time PCR assays for genus- and species-specific identification for commonly isolated species in whole blood for diagnosis of invasive Aspergillus infections offers a rapid, sensitive and specific assay option and requires clinical validation at multiple centers.

Molecular Detection and Species-Specific Identification of Medically Important Aspergillus Species by Real-Time PCR in Experimental Invasive Pulmonary Aspergillosis ▿

PubMed Central

Walsh, Thomas J.; Wissel, Mark C.; Grantham, Kevin J.; Petraitiene, Ruta; Petraitis, Vidmantas; Kasai, Miki; Francesconi, Andrea; Cotton, Margaret P.; Hughes, Johanna E.; Greene, Lora; Bacher, John D.; Manna, Pradip; Salomoni, Martin; Kleiboeker, Steven B.; Reddy, Sushruth K.

2011-01-01

Diagnosis of invasive pulmonary aspergillosis (IPA) remains a major challenge to clinical microbiology laboratories. We developed rapid and sensitive quantitative PCR (qPCR) assays for genus- and species-specific identification of Aspergillus infections by use of TaqMan technology. In order to validate these assays and understand their potential diagnostic utility, we then performed a blinded study of bronchoalveolar lavage (BAL) fluid specimens from well-characterized models of IPA with the four medically important species. A set of real-time qPCR primers and probes was developed by utilizing unique ITS1 regions for genus- and species-specific detection of the four most common medically important Aspergillus species (Aspergillus fumigatus, A. flavus, A. niger, and A. terreus). Pan-Aspergillus and species-specific qPCRs with BAL fluid were more sensitive than culture for detection of IPA caused by A. fumigatus in untreated (P < 0.0007) and treated (P ≤ 0.008) animals, respectively. For infections caused by A. terreus and A. niger, culture and PCR amplification from BAL fluid yielded similar sensitivities for untreated and treated animals. Pan-Aspergillus PCR was more sensitive than culture for detection of A. flavus in treated animals (P = 0.002). BAL fluid pan-Aspergillus and species-specific PCRs were comparable in sensitivity to BAL fluid galactomannan (GM) assay. The copy numbers from the qPCR assays correlated with quantitative cultures to determine the pulmonary residual fungal burdens in lung tissue. Pan-Aspergillus and species-specific qPCR assays may improve the rapid and accurate identification of IPA in immunocompromised patients. PMID:21976757

Enhanced efficiency fertilizers: A multi-site comparison of the effects on nitrous oxide emissions and agronomic performance

USDA-ARS?s Scientific Manuscript database

The need to understand the effects of enhanced efficiency fertilizers (EEF) for their effect on nitrous oxide emissions and agronomic performance was the motivation underpinning this multi-location study across North America. Research locations participating in this study included Ames, IA; Auburn, ...

EVALUATING THE ROLE OF HABITAT QUALITY ON ESTABLISHMENT OF GM AGROSTIS STOLONIFERA PLANTS IN NON-AGRONOMIC SETTINGS

EPA Science Inventory

We compared soil chemistry and plant community data at non-agronomic mesic locations that either did or did not contain genetically modified (GM) Agrostis stolonifera. The best two-variable logistic regression model included soil Mn content and A. stolonifera cover and explained...

Factors affecting plant species composition of hedgerows: relative importance and hierarchy

NASA Astrophysics Data System (ADS)

Deckers, Bart; Hermy, Martin; Muys, Bart

2004-07-01

Although there has been a clear quantitative and qualitative decline in traditional hedgerow network landscapes during last century, hedgerows are crucial for the conservation of rural biodiversity, functioning as an important habitat, refuge and corridor for numerous species. To safeguard this conservation function, insight in the basic organizing principles of hedgerow plant communities is needed. The vegetation composition of 511 individual hedgerows situated within an ancient hedgerow network landscape in Flanders, Belgium was recorded, in combination with a wide range of explanatory variables, including a selection of spatial variables. Non-parametric statistics in combination with multivariate data analysis techniques were used to study the effect of individual explanatory variables. Next, variables were grouped in five distinct subsets and the relative importance of these variable groups was assessed by two related variation partitioning techniques, partial regression and partial canonical correspondence analysis, taking into account explicitly the existence of intercorrelations between variables of different factor groups. Most explanatory variables affected significantly hedgerow species richness and composition. Multivariate analysis showed that, besides adjacent land use, hedgerow management, soil conditions, hedgerow type and origin, the role of other factors such as hedge dimensions, intactness, etc., could certainly not be neglected. Furthermore, both methods revealed the same overall ranking of the five distinct factor groups. Besides a predominant impact of abiotic environmental conditions, it was found that management variables and structural aspects have a relatively larger influence on the distribution of plant species in hedgerows than their historical background or spatial configuration.

Polyploidy and interspecific hybridization in Cynodon, Paspalum, Pennisetum, and Zoysia

USDA-ARS?s Scientific Manuscript database

There are many examples of agronomically or economically important characteristics in wild species, such as disease tolerance or quality, that are difficult to incorporate into related cultivated species due to differences in ploidy levels. Sterility, or at least reduced fertility, is common when w...

EFFECTS OF ALTERED HABITATS ON COMMERCIALLY IMPORTANT SPECIES OF THE NORTHERN GULF OF MEXICO

EPA Science Inventory

This research emphasizes the role of critical estuarine habitats to species that provide an ecosystem service, namely those fish and shellfish of economic importance. Vegetated habitats are examined for their capacity to provide and sustain commercially important shrimp, oyster, ...

PCR-RFLP on β-tubulin gene for rapid identification of the most clinically important species of Aspergillus.

PubMed

Nasri, Tuba; Hedayati, Mohammad Taghi; Abastabar, Mahdi; Pasqualotto, Alessandro C; Armaki, Mojtaba Taghizadeh; Hoseinnejad, Akbar; Nabili, Mojtaba

2015-10-01

Aspergillus species are important agents of life-threatening infections in immunosuppressed patients. Proper speciation in the Aspergilli has been justified based on varied fungal virulence, clinical presentations, and antifungal resistance. Accurate identification of Aspergillus species usually relies on fungal DNA sequencing but this requires expensive equipment that is not available in most clinical laboratories. We developed and validated a discriminative low-cost PCR-based test to discriminate Aspergillus isolates at the species level. The Beta tubulin gene of various reference strains of Aspergillus species was amplified using the universal fungal primers Bt2a and Bt2b. The PCR products were subjected to digestion with a single restriction enzyme AlwI. All Aspergillus isolates were subjected to DNA sequencing for final species characterization. The PCR-RFLP test generated unique patterns for six clinically important Aspergillus species, including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, Aspergillus terreus, Aspergillus clavatus and Aspergillus nidulans. The one-enzyme PCR-RFLP on Beta tubulin gene designed in this study is a low-cost tool for the reliable and rapid differentiation of the clinically important Aspergillus species. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative study on the gut microbiotas of four economically important Asian carp species.

PubMed

Li, Xinghao; Yu, Yuhe; Li, Chang; Yan, Qingyun

2018-05-07

Gut microbiota of four economically important Asian carp species (silver carp, Hypophthalmichthys molitrix; bighead carp, Hypophthalmichthys nobilis; grass carp, Ctenopharyngodon idella; common carp, Cyprinus carpio) were compared using 16S rRNA gene pyrosequencing. Analysis of more than 590,000 quality-filtered sequences obtained from the foregut, midgut and hindgut of these four carp species revealed high microbial diversity among the samples. The foregut samples of grass carp exhibited more than 1,600 operational taxonomy units (OTUs) and the highest alpha-diversity index, followed by the silver carp foregut and midgut. Proteobacteria, Firmicutes, Bacteroidetes and Fusobacteria were the predominant phyla regardless of fish species or gut type. Pairwise (weighted) UniFrac distance-based permutational multivariate analysis of variance with fish species as a factor produced significant association (P<0.01). The gut microbiotas of all four carp species harbored saccharolytic or proteolytic microbes, likely in response to the differences in their feeding habits. In addition, extensive variations were also observed even within the same fish species. Our results indicate that the gut microbiotas of Asian carp depend on the exact species, even when the different species were cohabiting in the same environment. This study provides some new insights into developing commercial fish feeds and improving existing aquaculture strategies.

Relation of agronomic and multispectral reflectance characteristics of spring wheat canopies

NASA Technical Reports Server (NTRS)

Bauer, M. E. (Principal Investigator); Ahlrichs, J. S.

1982-01-01

The relationships between crop canopy variables such as leaf area index (LAI) and their multispectral reflectance properties were investigated along with the potential for estimating canopy variables from remotely sensed reflectance measurements. Reflectance spectra over the 0.4 to 2.5 micron wavelength range were acquired during each of the major development stages of spring wheat canopies at Williston, North Dakota, during three seasons. Treatments included planting date, N fertilization, cultivar, and soil moisture. Agronomic measurements included development stage, biomass, LAI, and percent soil cover. High correlations were found between reflectance and percent cover, LAI, and biomass. A near infrared wavelength band, 0.76 to 0.90 microns, was most important in explaining variation in LAI and percent cover, while a middle infrared band, 2.08 to 2.35 microns, explained the most variation in biomass and plant water content. Transformations, including the near infrared/red reflectance ratio and greenness index, were also highly correlated to canopy variables. The relationship of canopy variables to reflectance decreased as the crop began to ripen. the canopy variables could be accurately predicted using measurements from three to five wavelength bands. The wavelength bands proposed for the thematic mapper sensor were more strongly related to the canopy variables than the LANDSAT MSS bands.

QQS orphan gene regulates carbon and nitrogen partitioning across species via NF-YC interactions

PubMed Central

Li, Ling; Zheng, Wenguang; Zhu, Yanbing; Ye, Huaxun; Tang, Buyun; Arendsee, Zebulun W.; Jones, Dallas; Li, Ruoran; Ortiz, Diego; Zhao, Xuefeng; Du, Chuanlong; Nettleton, Dan; Scott, M. Paul; Salas-Fernandez, Maria G.; Yin, Yanhai; Wurtele, Eve Syrkin

2015-01-01

The allocation of carbon and nitrogen resources to the synthesis of plant proteins, carbohydrates, and lipids is complex and under the control of many genes; much remains to be understood about this process. QQS (Qua-Quine Starch; At3g30720), an orphan gene unique to Arabidopsis thaliana, regulates metabolic processes affecting carbon and nitrogen partitioning among proteins and carbohydrates, modulating leaf and seed composition in Arabidopsis and soybean. Here the universality of QQS function in modulating carbon and nitrogen allocation is exemplified by a series of transgenic experiments. We show that ectopic expression of QQS increases soybean protein independent of the genetic background and original protein content of the cultivar. Furthermore, transgenic QQS expression increases the protein content of maize, a C4 species (a species that uses 4-carbon photosynthesis), and rice, a protein-poor agronomic crop, both highly divergent from Arabidopsis. We determine that QQS protein binds to the transcriptional regulator AtNF-YC4 (Arabidopsis nuclear factor Y, subunit C4). Overexpression of AtNF-YC4 in Arabidopsis mimics the QQS-overexpression phenotype, increasing protein and decreasing starch levels. NF-YC, a component of the NF-Y complex, is conserved across eukaryotes. The NF-YC4 homologs of soybean, rice, and maize also bind to QQS, which provides an explanation of how QQS can act in species where it does not occur endogenously. These findings are, to our knowledge, the first insight into the mechanism of action of QQS in modulating carbon and nitrogen allocation across species. They have major implications for the emergence and function of orphan genes, and identify a nontransgenic strategy for modulating protein levels in crop species, a trait of great agronomic significance. PMID:26554020

QQS orphan gene regulates carbon and nitrogen partitioning across species via NF-YC interactions.

PubMed

Li, Ling; Zheng, Wenguang; Zhu, Yanbing; Ye, Huaxun; Tang, Buyun; Arendsee, Zebulun W; Jones, Dallas; Li, Ruoran; Ortiz, Diego; Zhao, Xuefeng; Du, Chuanlong; Nettleton, Dan; Scott, M Paul; Salas-Fernandez, Maria G; Yin, Yanhai; Wurtele, Eve Syrkin

2015-11-24

The allocation of carbon and nitrogen resources to the synthesis of plant proteins, carbohydrates, and lipids is complex and under the control of many genes; much remains to be understood about this process. QQS (Qua-Quine Starch; At3g30720), an orphan gene unique to Arabidopsis thaliana, regulates metabolic processes affecting carbon and nitrogen partitioning among proteins and carbohydrates, modulating leaf and seed composition in Arabidopsis and soybean. Here the universality of QQS function in modulating carbon and nitrogen allocation is exemplified by a series of transgenic experiments. We show that ectopic expression of QQS increases soybean protein independent of the genetic background and original protein content of the cultivar. Furthermore, transgenic QQS expression increases the protein content of maize, a C4 species (a species that uses 4-carbon photosynthesis), and rice, a protein-poor agronomic crop, both highly divergent from Arabidopsis. We determine that QQS protein binds to the transcriptional regulator AtNF-YC4 (Arabidopsis nuclear factor Y, subunit C4). Overexpression of AtNF-YC4 in Arabidopsis mimics the QQS-overexpression phenotype, increasing protein and decreasing starch levels. NF-YC, a component of the NF-Y complex, is conserved across eukaryotes. The NF-YC4 homologs of soybean, rice, and maize also bind to QQS, which provides an explanation of how QQS can act in species where it does not occur endogenously. These findings are, to our knowledge, the first insight into the mechanism of action of QQS in modulating carbon and nitrogen allocation across species. They have major implications for the emergence and function of orphan genes, and identify a nontransgenic strategy for modulating protein levels in crop species, a trait of great agronomic significance.

Diversity of the Neglected and Underutilized Crop Species of Importance in Benin

PubMed Central

Dansi, A.; Vodouhè, R.; Azokpota, P.; Yedomonhan, H.; Assogba, P.; Adjatin, A.; Loko, Y. L.; Dossou-Aminon, I.; Akpagana, K.

2012-01-01

Many of the plant species that are cultivated for food across the world are neglected and underutilized. To assess their diversity in Benin and identify the priority species and establish their research needs, a survey was conducted in 50 villages distributed throughout the country. The study revealed 41 neglected and underutilized crop species (NUCS) among which 19 were identified as of priority base on 10 criteria among which included their extent and degree of consumption. Reasons for neglect vary with the producers and the agricultural technicians. Market surveys revealed that NUCS are important source of household incomes and substantially contribute to poverty reduction. Review of the literature available revealed that most of the species are rich in nutrients and have some proven medicinal values and the promotion of their use would help in combating malnutrition and improving the health status of the local populations. The knowledge gaps and research needs are immense on most of the species identified as no concrete scientific data is nationally available. In terms of research, almost all has to be done starting from basic ethnobotanical investigation. The results will help the scientists and students willing to conduct research on NUCS in Benin to better orient their research programs. PMID:22593712

An overview of important ethnomedicinal herbs of Phyllanthus species: present status and future prospects.

PubMed

Sarin, Bharti; Verma, Nidhi; Martín, Juan Pedro; Mohanty, Aparajita

2014-01-01

The genus Phyllanthus consists of more than 1000 species, of which many are used as traditional medicines. The plant extracts have been used since ancient times, for treating hypertension, diabetes, hepatic, urinary, and sexual disorders, and other common ailments. Modern day scientific investigations have now confirmed pharmacognostic properties of Phyllanthus herbs. The phytochemicals attributing these medicinal properties have been identified in many of the Phyllanthus herbs. The morphologically similar herbs of Phyllanthus grow together and admixture of species during collection for manufacture of herbal medicines is quite common. Hence, along with pharmacognostic and phytochemical studies, appropriate protocols for correct identification of species are also important. As the use of these herbs as green medicines is becoming more popular, it is imperative to assess its genetic diversity and phylogenetic relatedness for future conservation strategies. This review is an attempt to present an overview of the existing studies on pharmacognostics, phytochemistry, species identification, and genetic diversity of Phyllanthus herbs and consequently (i) highlight areas where further research is needed and (ii) draw attention towards extending similar studies in underutilized but potentially important herbs such as P. maderaspatensis, P. kozhikodianus, P. rheedii, P. scabrifolius, and P. rotundifolius.

An Overview of Important Ethnomedicinal Herbs of Phyllanthus Species: Present Status and Future Prospects

PubMed Central

Sarin, Bharti; Martín, Juan Pedro; Mohanty, Aparajita

2014-01-01

The genus Phyllanthus consists of more than 1000 species, of which many are used as traditional medicines. The plant extracts have been used since ancient times, for treating hypertension, diabetes, hepatic, urinary, and sexual disorders, and other common ailments. Modern day scientific investigations have now confirmed pharmacognostic properties of Phyllanthus herbs. The phytochemicals attributing these medicinal properties have been identified in many of the Phyllanthus herbs. The morphologically similar herbs of Phyllanthus grow together and admixture of species during collection for manufacture of herbal medicines is quite common. Hence, along with pharmacognostic and phytochemical studies, appropriate protocols for correct identification of species are also important. As the use of these herbs as green medicines is becoming more popular, it is imperative to assess its genetic diversity and phylogenetic relatedness for future conservation strategies. This review is an attempt to present an overview of the existing studies on pharmacognostics, phytochemistry, species identification, and genetic diversity of Phyllanthus herbs and consequently (i) highlight areas where further research is needed and (ii) draw attention towards extending similar studies in underutilized but potentially important herbs such as P. maderaspatensis, P. kozhikodianus, P. rheedii, P. scabrifolius, and P. rotundifolius. PMID:24672382

The importance of plot size and the number of sampling seasons on capturing macrofungal species richness.

PubMed

Li, Huili; Ostermann, Anne; Karunarathna, Samantha C; Xu, Jianchu; Hyde, Kevin D; Mortimer, Peter E

2018-07-01

The species-area relationship is an important factor in the study of species diversity, conservation biology, and landscape ecology. A deeper understanding of this relationship is necessary, in order to provide recommendations on how to improve the quality of data collection on macrofungal diversity in different land use systems in future studies, a systematic assessment of methodological parameters, in particular optimal plot sizes. The species-area relationship of macrofungi in tropical and temperate climatic zones and four different land use systems were investigated by determining the macrofungal species richness in plot sizes ranging from 100 m 2 to 10 000 m 2 over two sampling seasons. We found that the effect of plot size on recorded species richness significantly differed between land use systems with the exception of monoculture systems. For both climate zones, land use system needs to be considered when determining optimal plot size. Using an optimal plot size was more important than temporal replication (over two sampling seasons) in accurately recording species richness. Copyright © 2018 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Are ecologically important tree species the most useful? A case study from indigenous people in the Bolivian Amazon.

PubMed

Guèze, Maximilien; Luz, Ana Catarina; Paneque-Gálvez, Jaime; Macía, Manuel J; Orta-Martínez, Martí; Pino, Joan; Reyes-García, Victoria

2014-03-01

Researchers have argued that indigenous peoples preferably use the most apparent plant species, particularly for medicinal uses. However, the association between the ecological importance of a species and its usefulness remains unclear. In this paper we quantify such association for six use categories (firewood, construction, materials, food, medicines and other uses). We collected data on the uses of 58 tree species, as reported by 93 informants in 22 villages in the Tsimane' territory (Bolivian Amazon). We calculated the ecological importance of the same species by deriving their importance value index (IVI) in 48 0.1-ha old-growth forest plots. Matching both data sets, we found a positive relation between the IVI of a species and its overall use value (UV) as well as with its UV for construction and materials. We found a negative relation between IVI and UV for species that were reportedly used for medicine and food uses, and no clear pattern for the other categories. We hypothesize that species used for construction or crafting purposes because of their physical properties are more easily substitutable than species used for medicinal or edible purposes because of their chemical properties.

Are ecologically important tree species the most useful? A case study from indigenous people in the Bolivian Amazon

PubMed Central

Guèze, Maximilien; Luz, Ana Catarina; Paneque-Gálvez, Jaime; Macía, Manuel J.; Orta-Martínez, Martí; Pino, Joan; Reyes-García, Victoria

2015-01-01

Researchers have argued that indigenous peoples preferably use the most apparent plant species, particularly for medicinal uses. However, the association between the ecological importance of a species and its usefulness remains unclear. In this paper we quantify such association for six use categories (firewood, construction, materials, food, medicines and other uses). We collected data on the uses of 58 tree species, as reported by 93 informants in 22 villages in the Tsimane’ territory (Bolivian Amazon). We calculated the ecological importance of the same species by deriving their importance value index (IVI) in 48 0.1-ha old-growth forest plots. Matching both data sets, we found a positive relation between the IVI of a species and its overall use value (UV) as well as with its UV for construction and materials. We found a negative relation between IVI and UV for species that were reportedly used for medicine and food uses, and no clear pattern for the other categories. We hypothesize that species used for construction or crafting purposes because of their physical properties are more easily substitutable than species used for medicinal or edible purposes because of their chemical properties. PMID:26097243

Microplastics as contaminants in commercially important seafood species.

PubMed

Santillo, David; Miller, Kathryn; Johnston, Paul

2017-05-01

The ingestion of microplastic fragments, spheres, and fibers by marine mollusks, crustaceans, and fish, including a number of commercially important species, appears to be a widespread and pervasive phenomenon. Evidence is also growing for direct impacts of microplastic ingestion on physiology, reproductive success and survival of exposed marine organisms, and transfer through food webs, although the ecological implications are not yet known. Concerns also remain over the capacity for microplastics to act as vectors for harmful chemical pollutants, including plastic additives and persistent organic pollutants, although their contribution must be evaluated alongside other known sources. The potential for humans, as top predators, to consume microplastics as contaminants in seafood is very real, and its implications for health need to be considered. An urgent need also exists to extend the geographical scope of studies of microplastic contamination in seafood species to currently underrepresented areas, and to finalize and adopt standardized methods and quality-assurance protocols for the isolation, identification, and quantification of microplastic contaminants from biological tissues. Such developments would enable more robust investigation of spatial and temporal trends, thereby contributing further evidence as a sound basis for regulatory controls. Despite the existence of considerable uncertainties and unknowns, there is already a compelling case for urgent actions to identify, control, and, where possible, eliminate key sources of both primary and secondary microplastics before they reach the marine environment. Integr Environ Assess Manag 2017;13:516-521. © 2017 SETAC. © 2017 SETAC.

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution.

PubMed

Oji, Tatsuo; Dornbos, Stephen Q; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the 'agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum . These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

PubMed Central

Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-01-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the ‘agronomic revolution’. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered. PMID:29515908

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

NASA Astrophysics Data System (ADS)

Oji, Tatsuo; Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the `agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

Important biological factors for utilizing native plant species

Treesearch

Loren E. Wiesner

1999-01-01

Native plant species are valuable resources for revegetation of disturbed ecosystems. The success of these plantings is dependent on the native species selected, quality of seed used, condition of the soil, environmental conditions before and after planting, planting equipment used, time of planting, and other factors. Most native species contain dormant seed. Dormancy...

Phytochemical overview and medicinal importance of Coffea species from the past until now.

PubMed

Patay, Éva Brigitta; Bencsik, Tímea; Papp, Nóra

2016-12-01

Coffea (coffee) species are grown in almost all countries along the Equator. Many members of the genus have a large production history and an important role both in the global market and researches. Seeds (Coffeae semen) are successfully used in food, cosmetic, and pharmaceutical industries due to its caffeine and high polyphenol content. Nowadays, the three best-known coffee species are Arabic (Coffea arabica L.), Robusta (Coffea robusta L. Linden), and Liberian coffees (Coffea liberica Hiern.). Even though, many records are available on coffee in scientific literature, wild coffee species like Bengal coffee (Coffea benghalensis Roxb. Ex Schult.) could offer many new opportunities and challenges for phytochemical and medical studies. In this comprehensive summary, we focused on the ethnomedicinal, phytochemical, and medical significance of coffee species up to the present. Copyright © 2016 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Species Sorting of Benthic Invertebrates in a Salinity Gradient - Importance of Dispersal Limitation.

PubMed

Josefson, Alf B

2016-01-01

The relative importance of environment and dispersal related processes for community assembly has attracted great interest over recent decades, but few empirical studies from the marine/estuarine realm have examined the possible effects of these two types of factors in the same system. Importance of these processes was investigated in a hypothetical metacommunity of benthic invertebrates in 16 micro-tidal estuaries connected to the same open sea area. The estuaries differed in size and connectivity to the open sea and represented a salinity gradient across the estuaries. The Elements of Metacommunity Structure (EMS) approach on estuary scale was complemented with a mechanistic variance partitioning approach on sample scale to disentangle effects of factors affecting assembly of three trait groups of species with different dispersivity. A quasi-Clementsian pattern was observed for all three traits, a likely response to some latent gradient. The primary axis in the pattern was most strongly related to gradients in estuary salinity and estuary entrance width and correlation with richness indicated nestedness only in the matrix of the most dispersive trait group. In the variance partitioning approach measures of turnover and nestedness between paired samples each from different estuaries were related to environmental distance in different gradients. Distance between estuaries was unimportant suggesting importance of factors characterizing the estuaries. While the high dispersive species mainly were sorted in the salinity gradient, apparently according to their tolerance ranges towards salinity, the two less dispersive traits were additionally affected by estuary entrance width and possibly also area. The results exemplify a mechanism of community assembly in the marine realm where the niche factor salinity in conjunction with differential dispersal structure invertebrates in a metacommunity of connected estuaries, and support the idea that dispersive species are more

The Application of COI Gene for Species Identification of Forensically Important Muscid Flies (Diptera: Muscidae).

PubMed

Ren, Lipin; Chen, Wei; Shang, Yanjie; Meng, Fanming; Zha, Lagabaiyila; Wang, Yong; Guo, Yadong

2018-05-17

Muscid Flies (Diptera: Muscidae) are of great forensic importance due to their wide distribution, ubiquitous and synanthropic nature. They are frequently neglected as they tend to arrive at the corpses later than the flesh flies and blow flies. Moreover, the lack of species-level identification also hinders investigation of medicolegal purposes. To overcome the difficulty of morphological identification, molecular method has gained relevance. Cytochrome c oxidase subunit I (COI) gene has been widely utilized. Nonetheless, to achieve correct identification of an unknown sample, it is important to survey certain muscid taxa from its geographic distribution range. Accordingly, the aim of this study is to contribute more geographically specific. We sequenced the COI gene of 51 muscid specimens of 12 species, and added all correct sequences available in GenBank to yield a total data set of 125 COI sequences from 33 muscid species to evaluate the COI gene as a molecular diagnostic tool. The interspecific distances were extremely high (4.7-19.8%) in either the standard barcoding fragment (658 bp) or the long COI sequence (1,019-1,535 bp), demonstrating that these two genetic markers were nearly identical in the species identification. However, the intraspecific distances of the long COI sequences were significantly higher than the barcoding region for the conspecific species that geographical locations vary greatly. Therefore, genetic diversity presented in this study provides a reference for species identification of muscid flies. Nevertheless, further investigation and data from more muscid species are required to enhance the efficacy of species-level identification using COI gene as a genetic marker.

Ultra-high density intra-specific genetic linkage maps accelerate identification of functionally relevant molecular tags governing important agronomic traits in chickpea

PubMed Central

Kujur, Alice; Upadhyaya, Hari D.; Shree, Tanima; Bajaj, Deepak; Das, Shouvik; Saxena, Maneesha S.; Badoni, Saurabh; Kumar, Vinod; Tripathi, Shailesh; Gowda, C. L. L.; Sharma, Shivali; Singh, Sube; Tyagi, Akhilesh K.; Parida, Swarup K.

2015-01-01

We discovered 26785 and 16573 high-quality SNPs differentiating two parental genotypes of a RIL mapping population using reference desi and kabuli genome-based GBS assay. Of these, 3625 and 2177 SNPs have been integrated into eight desi and kabuli chromosomes, respectively in order to construct ultra-high density (0.20–0.37 cM) intra-specific chickpea genetic linkage maps. One of these constructed high-resolution genetic map has potential to identify 33 major genomic regions harbouring 35 robust QTLs (PVE: 17.9–39.7%) associated with three agronomic traits, which were mapped within <1 cM mean marker intervals on desi chromosomes. The extended LD (linkage disequilibrium) decay (~15 cM) in chromosomes of genetic maps have encouraged us to use a rapid integrated approach (comparative QTL mapping, QTL-region specific haplotype/LD-based trait association analysis, expression profiling and gene haplotype-based association mapping) rather than a traditional QTL map-based cloning method to narrow-down one major seed weight (SW) robust QTL region. It delineated favourable natural allelic variants and superior haplotype-containing one seed-specific candidate embryo defective gene regulating SW in chickpea. The ultra-high-resolution genetic maps, QTLs/genes and alleles/haplotypes-related genomic information generated and integrated strategy for rapid QTL/gene identification developed have potential to expedite genomics-assisted breeding applications in crop plants, including chickpea for their genetic enhancement. PMID:25942004

Isotope ratio mass spectrometry in combination with chemometrics for characterization of geographical origin and agronomic practices of table grape.

PubMed

Longobardi, Francesco; Casiello, Grazia; Centonze, Valentina; Catucci, Lucia; Agostiano, Angela

2017-08-01

Although table grape is one of the most cultivated and consumed fruits worldwide, no study has been reported on its geographical origin or agronomic practice based on stable isotope ratios. This study aimed to evaluate the usefulness of isotopic ratios (i.e. 2 H/ 1 H, 13 C/ 12 C, 15 N/ 14 N and 18 O/ 16 O) as possible markers to discriminate the agronomic practice (conventional versus organic farming) and provenance of table grape. In order to quantitatively evaluate which of the isotopic variables were more discriminating, a t test was carried out, in light of which only δ 13 C and δ 18 O provided statistically significant differences (P ≤ 0.05) for the discrimination of geographical origin and farming method. Principal component analysis (PCA) showed no good separation of samples differing in geographical area and agronomic practice; thus, for classification purposes, supervised approaches were carried out. In particular, general discriminant analysis (GDA) was used, resulting in prediction abilities of 75.0 and 92.2% for the discrimination of farming method and origin respectively. The present findings suggest that stable isotopes (i.e. δ 18 O, δ 2 H and δ 13 C) combined with chemometrics can be successfully applied to discriminate the provenance of table grape. However, the use of bulk nitrogen isotopes was not effective for farming method discrimination. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

IMPROVING BIOMASS LOGISTICS COST WITHIN AGRONOMIC SUSTAINABILITY CONSTRAINTS AND BIOMASS QUALITY TARGETS

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

J. Richard Hess; Kevin L. Kenney; Christopher T. Wright

Equipment manufacturers have made rapid improvements in biomass harvesting and handling equipment. These improvements have increased transportation and handling efficiencies due to higher biomass densities and reduced losses. Improvements in grinder efficiencies and capacity have reduced biomass grinding costs. Biomass collection efficiencies (the ratio of biomass collected to the amount available in the field) as high as 75% for crop residues and greater than 90% for perennial energy crops have also been demonstrated. However, as collection rates increase, the fraction of entrained soil in the biomass increases, and high biomass residue removal rates can violate agronomic sustainability limits. Advancements inmore » quantifying multi-factor sustainability limits to increase removal rate as guided by sustainable residue removal plans, and mitigating soil contamination through targeted removal rates based on soil type and residue type/fraction is allowing the use of new high efficiency harvesting equipment and methods. As another consideration, single pass harvesting and other technologies that improve harvesting costs cause biomass storage moisture management challenges, which challenges are further perturbed by annual variability in biomass moisture content. Monitoring, sampling, simulation, and analysis provide basis for moisture, time, and quality relationships in storage, which has allowed the development of moisture tolerant storage systems and best management processes that combine moisture content and time to accommodate baled storage of wet material based upon “shelf-life.” The key to improving biomass supply logistics costs has been developing the associated agronomic sustainability and biomass quality technologies and processes that allow the implementation of equipment engineering solutions.« less

Multivariate diallel analysis allows multiple gains in segregating populations for agronomic traits in Jatropha.

PubMed

Teodoro, P E; Rodrigues, E V; Peixoto, L A; Silva, L A; Laviola, B G; Bhering, L L

2017-03-22

Jatropha is research target worldwide aimed at large-scale oil production for biodiesel and bio-kerosene. Its production potential is among 1200 and 1500 kg/ha of oil after the 4th year. This study aimed to estimate combining ability of Jatropha genotypes by multivariate diallel analysis to select parents and crosses that allow gains in important agronomic traits. We performed crosses in diallel complete genetic design (3 x 3) arranged in blocks with five replications and three plants per plot. The following traits were evaluated: plant height, stem diameter, canopy projection between rows, canopy projection on the line, number of branches, mass of hundred grains, and grain yield. Data were submitted to univariate and multivariate diallel analysis. Genotypes 107 and 190 can be used in crosses for establishing a base population of Jatropha, since it has favorable alleles for increasing the mass of hundred grains and grain yield and reducing the plant height. The cross 190 x 107 is the most promising to perform the selection of superior genotypes for the simultaneous breeding of these traits.

Stakeholder perspectives on the importance of rare-species research for deep-sea environmental management

NASA Astrophysics Data System (ADS)

Turner, Phillip J.; Campbell, Lisa M.; Van Dover, Cindy L.

2017-07-01

The apparent prevalence of rare species (rarity) in the deep sea is a concern for environmental management and conservation of biodiversity. Rare species are often considered at risk of extinction and, in terrestrial and shallow water environments, have been shown to play key roles within an ecosystem. In the deep-sea environment, current research focuses primarily on abundant species and deep-sea stakeholders are questioning the importance of rare species in ecosystem functioning. This study asks whether deep-sea stakeholders (primarily scientists) view rare-species research as a priority in guiding environmental management. Delphi methodology (i.e., an iterative survey approach) was used to understand views about whether or not 'deep-sea scientists should allocate more resources to research on rare species in the deep sea, even if this means less resources might be available for abundant-species research.' Results suggest little consensus regarding the prioritization of resources for rare-species research. From Survey 1 to Survey 3, the average participant response shifted toward a view that rare-species research is not a priority if it comes at a cost to research on abundant species. Participants pointed to the need for a balanced approach and highlighted knowledge gaps about even the most fundamental questions, including whether rare species are truly 'rare' or simply under-sampled. Participants emphasized the lack of basic biological knowledge for rare and abundant species, particularly abundant meio- and microscopic species, as well as uncertainty in the roles rare and abundant species play in ecosystem processes. Approaches that jointly consider the role of rare and abundant species in ecosystem functioning (e.g., biological trait analysis) may help to clarify the extent to which rare species need to be incorporated into deep-sea environment management in order to maintain ecosystem functioning.

Using the Developmental Gene Bicoid to Identify Species of Forensically Important Blowflies (Diptera: Calliphoridae)

PubMed Central

Park, Seong Hwan; Park, Chung Hyun; Zhang, Yong; Piao, Huguo; Chung, Ukhee; Kim, Seong Yoon; Ko, Kwang Soo; Yi, Cheong-Ho; Jo, Tae-Ho; Hwang, Juck-Joon

2013-01-01

Identifying species of insects used to estimate postmortem interval (PMI) is a major subject in forensic entomology. Because forensic insect specimens are morphologically uniform and are obtained at various developmental stages, DNA markers are greatly needed. To develop new autosomal DNA markers to identify species, partial genomic sequences of the bicoid (bcd) genes, containing the homeobox and its flanking sequences, from 12 blowfly species (Aldrichina grahami, Calliphora vicina, Calliphora lata, Triceratopyga calliphoroides, Chrysomya megacephala, Chrysomya pinguis, Phormia regina, Lucilia ampullacea, Lucilia caesar, Lucilia illustris, Hemipyrellia ligurriens and Lucilia sericata; Calliphoridae: Diptera) were determined and analyzed. This study first sequenced the ten blowfly species other than C. vicina and L. sericata. Based on the bcd sequences of these 12 blowfly species, a phylogenetic tree was constructed that discriminates the subfamilies of Calliphoridae (Luciliinae, Chrysomyinae, and Calliphorinae) and most blowfly species. Even partial genomic sequences of about 500 bp can distinguish most blowfly species. The short intron 2 and coding sequences downstream of the bcd homeobox in exon 3 could be utilized to develop DNA markers for forensic applications. These gene sequences are important in the evolution of insect developmental biology and are potentially useful for identifying insect species in forensic science. PMID:23586044

Genome-wide association studies dissect the genetic networks underlying agronomical traits in soybean.

PubMed

Fang, Chao; Ma, Yanming; Wu, Shiwen; Liu, Zhi; Wang, Zheng; Yang, Rui; Hu, Guanghui; Zhou, Zhengkui; Yu, Hong; Zhang, Min; Pan, Yi; Zhou, Guoan; Ren, Haixiang; Du, Weiguang; Yan, Hongrui; Wang, Yanping; Han, Dezhi; Shen, Yanting; Liu, Shulin; Liu, Tengfei; Zhang, Jixiang; Qin, Hao; Yuan, Jia; Yuan, Xiaohui; Kong, Fanjiang; Liu, Baohui; Li, Jiayang; Zhang, Zhiwu; Wang, Guodong; Zhu, Baoge; Tian, Zhixi

2017-08-24

Soybean (Glycine max [L.] Merr.) is one of the most important oil and protein crops. Ever-increasing soybean consumption necessitates the improvement of varieties for more efficient production. However, both correlations among different traits and genetic interactions among genes that affect a single trait pose a challenge to soybean breeding. To understand the genetic networks underlying phenotypic correlations, we collected 809 soybean accessions worldwide and phenotyped them for two years at three locations for 84 agronomic traits. Genome-wide association studies identified 245 significant genetic loci, among which 95 genetically interacted with other loci. We determined that 14 oil synthesis-related genes are responsible for fatty acid accumulation in soybean and function in line with an additive model. Network analyses demonstrated that 51 traits could be linked through the linkage disequilibrium of 115 associated loci and these links reflect phenotypic correlations. We revealed that 23 loci, including the known Dt1, E2, E1, Ln, Dt2, Fan, and Fap loci, as well as 16 undefined associated loci, have pleiotropic effects on different traits. This study provides insights into the genetic correlation among complex traits and will facilitate future soybean functional studies and breeding through molecular design.

Agronomic threshold of soil available phosphorus in grey desert soils in Xinjiang, China

NASA Astrophysics Data System (ADS)

Wang, B.; Liu, H.; Hao, X. Y.; Wang, X. H.; Sun, J. S.; Li, J. M.; Ma, Y. B.

2016-08-01

Based on 23 years of data, yields of maize, wheat and cotton were modelled under different fertilizer management practices and at different levels of available phosphorus (Olsen-P) in soil. Three types of threshold models were used, namely linear-linear (LL), linear- plateau (LP), and Mitscherlich type exponential (Exp). The agronomic thresholds of available phosphorus were 25.4 mgkg-1 for cotton, 14.8 mgkg-1 for wheat, 13.1 mgkg-1 for maize and 25.4 mgkg-1 for the grey desert soil regions of Xinjiang in China as a whole.

Correlation, path analysis and heritability estimation for agronomic traits contribute to yield on soybean

NASA Astrophysics Data System (ADS)

Sulistyo, A.; Purwantoro; Sari, K. P.

2018-01-01

Selection is a routine activity in plant breeding programs that must be done by plant breeders in obtaining superior plant genotypes. The use of appropriate selection criteria will determine the effectiveness of selection activities. The purpose of this study was to analysis the inheritable agronomic traits that contribute to soybean yield. A total of 91 soybean lines were planted in Muneng Experimental Station, Probolinggo District, East Java Province, Indonesia in 2016. All soybean lines were arranged in randomized complete block design with two replicates. Correlation analysis, path analysis and heritability estimation were performed on days to flowering, days to maturing, plant height, number of branches, number of fertile nodes, number of filled pods, weight of 100 seeds, and yield to determine selection criteria on soybean breeding program. The results showed that the heritability value of almost all agronomic traits observed is high except for the number of fertile nodes with low heritability. The result of correlation analysis shows that days to flowering, plant height and number of fertile nodes have positive correlation with seed yield per plot (0.056, 0.444, and 0.100, respectively). In addition, path analysis showed that plant height and number of fertile nodes have highest positive direct effect on soybean yield. Based on this result, plant height can be selected as one of selection criteria in soybean breeding program to obtain high yielding soybean variety.

Robust Detection of Rare Species Using Environmental DNA: The Importance of Primer Specificity

PubMed Central

Wilcox, Taylor M.; McKelvey, Kevin S.; Young, Michael K.; Jane, Stephen F.; Lowe, Winsor H.; Whiteley, Andrew R.; Schwartz, Michael K.

2013-01-01

Environmental DNA (eDNA) is being rapidly adopted as a tool to detect rare animals. Quantitative PCR (qPCR) using probe-based chemistries may represent a particularly powerful tool because of the method’s sensitivity, specificity, and potential to quantify target DNA. However, there has been little work understanding the performance of these assays in the presence of closely related, sympatric taxa. If related species cause any cross-amplification or interference, false positives and negatives may be generated. These errors can be disastrous if false positives lead to overestimate the abundance of an endangered species or if false negatives prevent detection of an invasive species. In this study we test factors that influence the specificity and sensitivity of TaqMan MGB assays using co-occurring, closely related brook trout (Salvelinus fontinalis) and bull trout (S. confluentus) as a case study. We found qPCR to be substantially more sensitive than traditional PCR, with a high probability of detection at concentrations as low as 0.5 target copies/µl. We also found that number and placement of base pair mismatches between the Taqman MGB assay and non-target templates was important to target specificity, and that specificity was most influenced by base pair mismatches in the primers, rather than in the probe. We found that insufficient specificity can result in both false positive and false negative results, particularly in the presence of abundant related species. Our results highlight the utility of qPCR as a highly sensitive eDNA tool, and underscore the importance of careful assay design. PMID:23555689

Robust detection of rare species using environmental DNA: the importance of primer specificity.

PubMed

Wilcox, Taylor M; McKelvey, Kevin S; Young, Michael K; Jane, Stephen F; Lowe, Winsor H; Whiteley, Andrew R; Schwartz, Michael K

2013-01-01

Environmental DNA (eDNA) is being rapidly adopted as a tool to detect rare animals. Quantitative PCR (qPCR) using probe-based chemistries may represent a particularly powerful tool because of the method's sensitivity, specificity, and potential to quantify target DNA. However, there has been little work understanding the performance of these assays in the presence of closely related, sympatric taxa. If related species cause any cross-amplification or interference, false positives and negatives may be generated. These errors can be disastrous if false positives lead to overestimate the abundance of an endangered species or if false negatives prevent detection of an invasive species. In this study we test factors that influence the specificity and sensitivity of TaqMan MGB assays using co-occurring, closely related brook trout (Salvelinus fontinalis) and bull trout (S. confluentus) as a case study. We found qPCR to be substantially more sensitive than traditional PCR, with a high probability of detection at concentrations as low as 0.5 target copies/µl. We also found that number and placement of base pair mismatches between the Taqman MGB assay and non-target templates was important to target specificity, and that specificity was most influenced by base pair mismatches in the primers, rather than in the probe. We found that insufficient specificity can result in both false positive and false negative results, particularly in the presence of abundant related species. Our results highlight the utility of qPCR as a highly sensitive eDNA tool, and underscore the importance of careful assay design.

De novo assembly of soybean wild relatives for pan-genome analysis of diversity and agronomic traits.

PubMed

Li, Ying-hui; Zhou, Guangyu; Ma, Jianxin; Jiang, Wenkai; Jin, Long-guo; Zhang, Zhouhao; Guo, Yong; Zhang, Jinbo; Sui, Yi; Zheng, Liangtao; Zhang, Shan-shan; Zuo, Qiyang; Shi, Xue-hui; Li, Yan-fei; Zhang, Wan-ke; Hu, Yiyao; Kong, Guanyi; Hong, Hui-long; Tan, Bing; Song, Jian; Liu, Zhang-xiong; Wang, Yaoshen; Ruan, Hang; Yeung, Carol K L; Liu, Jian; Wang, Hailong; Zhang, Li-juan; Guan, Rong-xia; Wang, Ke-jing; Li, Wen-bin; Chen, Shou-yi; Chang, Ru-zhen; Jiang, Zhi; Jackson, Scott A; Li, Ruiqiang; Qiu, Li-juan

2014-10-01

Wild relatives of crops are an important source of genetic diversity for agriculture, but their gene repertoire remains largely unexplored. We report the establishment and analysis of a pan-genome of Glycine soja, the wild relative of cultivated soybean Glycine max, by sequencing and de novo assembly of seven phylogenetically and geographically representative accessions. Intergenomic comparisons identified lineage-specific genes and genes with copy number variation or large-effect mutations, some of which show evidence of positive selection and may contribute to variation of agronomic traits such as biotic resistance, seed composition, flowering and maturity time, organ size and final biomass. Approximately 80% of the pan-genome was present in all seven accessions (core), whereas the rest was dispensable and exhibited greater variation than the core genome, perhaps reflecting a role in adaptation to diverse environments. This work will facilitate the harnessing of untapped genetic diversity from wild soybean for enhancement of elite cultivars.

Changes in tree species importance following harvesting disturbance in north Mississippi between 1967 and 1994

Treesearch

Andrew J. Hartsell; James F. Rosson

2007-01-01

We used continuous forest inventory data from the Forest Inventory and Analysis unit of the U.S. Department of Agriculture, Forest Service to study the impacts of timber harvesting on species composition and species importance in a 26-county region in north Mississippi. The region was 59 percent forested and contained 1 965 223 ha of timberland. There were 524 upland...

Agronomic efficiency of phosphate fertilizers produced by the re-use of a metallurgical acid residue.

PubMed

Barreto, Matheus Sampaio Carneiro; Mattiello, Edson Marcio; Santos, Wedisson Oliveira; Melo, Leônidas Carrijo Azevedo; Vergütz, Leonardus; Novais, Roberto Ferreira

2018-02-15

The production of fertilizers with industrial wastes reduces the environmental impacts of waste disposal and improves environmental sustainability by generating added-value products. Our objective with this study was to evaluate the agronomic performance and potential soil/plant contamination with heavy metals of alternative phosphate (P) fertilizers, obtained from the acidulation of phosphate rocks (PR) by a metallurgical acidic waste. Seven P fertilizers were evaluated: three PR (Araxá, Patos, and Bayóvar), their respective acidulated products (PAPR), and triple superphosphate fertilizer (TSP). A greenhouse trial was carried out to test the agronomic performances of fertilizers in a sequentially cultivated maize-soybean-white oat. The reaction of PR with acid waste was effective to increase their solubility and improve plant yield and P uptake compared to their natural PR. There was a cumulative recovery by plants of 1.4 and 8.1% of added P via PR and PAPR, respectively. No increase in heavy metal (Cd, Pb, Cr, and Ni) availability in soil or accumulation in shoots was observed, indicating that the PAPR were environmentally safe. The usage of acid waste to produce P fertilizers therefore represents a strategic way to employ marginal products for the production of fertilizers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diapause in ticks of the medically important Ixodes ricinus species complex

PubMed Central

Gray, Jeremy S.; Kahl, Olaf; Lane, Robert S.; Levin, Michael L.; Tsao, Jean I.

2017-01-01

Four members of the Ixodes ricinus species complex, Ixodes pacificus, Ixodes persulcatus, Ixodes ricinus and Ixodes scapularis, have, between them, a worldwide distribution within the northern hemisphere. They are responsible for the transmission of several animal and human pathogens, including the causal agents of Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis and human babesiosis. Despite the importance of these ticks as vectors, the knowledge and understanding of the role that diapause plays in their complex life cycles are confused and incomplete. In view of the continuing geographic spread of these tick species, as well as the effects of climate change on vector-borne diseases, it is timely encourage research on diapause phenomena to improve understanding of their biology and of pathogen transmission dynamics. In our review we seek to clarify thinking on the topic and to address gaps in our knowledge that require the attention of researchers. PMID:27263092

Phenological adjustment in arctic bird species: relative importance of snow melt and ecological factors

USGS Publications Warehouse

Liebezeit, Joseph R.; Gurney, K. E. B.; Budde, Michael E.; Zack, Steve; Ward, David H.

2014-01-01

Previous studies have documented advancement in clutch initiation dates (CIDs) in response to climate change, most notably for temperate-breeding passerines. Despite accelerated climate change in the Arctic, few studies have examined nest phenology shifts in arctic breeding species. We investigated whether CIDs have advanced for the most abundant breeding shorebird and passerine species at a long-term monitoring site in arctic Alaska. We pooled data from three additional nearby sites to determine the explanatory power of snow melt and ecological variables (predator abundance, green-up) on changes in breeding phenology. As predicted, all species (semipalmated sandpiper, Calidris pusilla, pectoral sandpiper, Calidris melanotos, red-necked phalarope, Phalaropus lobatus, red phalarope, Phalaropus fulicarius, Lapland longspur, Calcarius lapponicus) exhibited advanced CIDs ranging from 0.40 to 0.80 days/year over 9 years. Timing of snow melt was the most important variable in explaining clutch initiation advancement (“climate/snow hypothesis”) for four of the five species, while green-up was a much less important explanatory factor. We found no evidence that high predator abundances led to earlier laying dates (“predator/re-nest hypothesis”). Our results support previous arctic studies in that climate change in the cryosphere will have a strong impact on nesting phenology although factors explaining changes in nest phenology are not necessarily uniform across the entire Arctic. Our results suggest some arctic-breeding shorebird and passerine species are altering their breeding phenology to initiate nesting earlier enabling them to, at least temporarily, avoid the negative consequences of a trophic mismatch.

Geographic distribution, evolution, and disease importance of species within the Neotropical Anopheles albitarsis Group (Diptera, Culicidae).

PubMed

Foley, Desmond H; Linton, Yvonne-Marie; Ruiz-Lopez, J Freddy; Conn, Jan E; Sallum, Maria Anice M; Póvoa, Marinete M; Bergo, Eduardo S; Oliveira, Tatiane M P; Sucupira, Izis; Wilkerson, Richard C

2014-06-01

The Anopheles albitarsis group of mosquitoes comprises eight recognized species and one mitochondrial lineage. Our knowledge of malaria vectorial importance and the distribution and evolution of these taxa is incomplete. We constructed ecological niche models (ENMs) for these taxa and used hypothesized phylogenetic relationships and ENMs to investigate environmental and ecological divergence associated with speciation events. Two major clades were identified, one north (Clade 1) and one south (Clade 2) of the Amazon River that likely is or was a barrier to mosquito movement. Clade 1 species occur more often in higher average temperature locations than Clade 2 species, and taxon splits within Clade 1 corresponded with a greater divergence of variables related to precipitation than was the case within Clade 2. Comparison of the ecological profiles of sympatric species and sister species support the idea that phylogenetic proximity is related to ecological similarity. Anopheles albitarsis I, An. janconnae, and An. marajoara ENMs had the highest percentage of their predicted suitable habitat overlapping distribution models of Plasmodium falciparum and P. vivax, and warrant additional studies of the transmission potential of these species. Phylogenetic proximity may be related to malaria vectorial importance within the Albitarsis Group. © 2014 The Society for Vector Ecology.

Identifying 1st instar larvae for three forensically important blowfly species using "fingerprint" cuticular hydrocarbon analysis.

PubMed

Moore, Hannah E; Adam, Craig D; Drijfhout, Falko P

2014-07-01

Calliphoridae are known to be the most forensically important insects when it comes to establishing the minimum post mortem interval (PMImin) in criminal investigations. The first step in calculating the PMImin is to identify the larvae present to species level. Accurate identification which is conventionally carried out by morphological analysis is crucial because different insects have different life stage timings. Rapid identification in the immature larvae stages would drastically cut time in criminal investigations as it would eliminate the need to rear larvae to adult flies to determine the species. Cuticular hydrocarbon analysis on 1st instar larvae has been applied to three forensically important blowflies; Lucilia sericata, Calliphora vicina and Calliphora vomitoria, using gas chromatography-mass spectrometry (GC-MS) and principal component analysis (PCA). The results show that each species holds a distinct "fingerprint" hydrocarbon profile, allowing for accurate identification to be established in 1-day old larvae, when it can be challenging to apply morphological criteria. Consequently, this GC-MS based technique could accelerate and strengthen the identification process, not only for forensically important species, but also for other entomological samples which are hard to identify using morphological features. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Larval morphology of Atherigona orientalis (Schiner) (Diptera: Muscidae) -a species of sanitary and forensic importance.

PubMed

Grzywacz, Andrzej; Pape, Thomas

2014-09-01

Larval morphology is documented using both light and scanning electron microscopy for all three instars of the muscid fly Atherigona orientalis (Schiner), which is a species of known sanitary and forensic importance found in tropical and subtropical areas of all biogeographic regions. The unpaired sclerite in a form of a spicule is reported herein in the second and the third instar larvae. Occurrence of this sclerite was hitherto unknown in the second instar larvae of Muscidae and was only known from the third instar of several species, however not in a form of a spicule. Our study is the first report of the occurrence of the "sensory organ X" in all three larval instars of a species representing the family Muscidae. The bubble membrane, previously known only from third instar cyclorrhaphan larvae, is reported herein for the first time in the second instar. Characters allowing for discrimination of A. orientalis larvae from other forensically important Muscidae are summarised. Copyright © 2014 Elsevier B.V. All rights reserved.

Francisella-Like Endosymbionts and Rickettsia Species in Local and Imported Hyalomma Ticks.

PubMed

Azagi, Tal; Klement, Eyal; Perlman, Gidon; Lustig, Yaniv; Mumcuoglu, Kosta Y; Apanaskevich, Dmitry A; Gottlieb, Yuval

2017-09-15

Hyalomma ticks (Acari: Ixodidae) are hosts for Francisella -like endosymbionts (FLE) and may serve as vectors of zoonotic disease agents. This study aimed to provide an initial characterization of the interaction between Hyalomma and FLE and to determine the prevalence of pathogenic Rickettsia in these ticks. Hyalomma marginatum , Hyalomma rufipes , Hyalomma dromedarii , Hyalomma aegyptium , and Hyalomma excavatum ticks, identified morphologically and molecularly, were collected from different hosts and locations representing the distribution of the genus Hyalomma in Israel, as well as from migratory birds. A high prevalence of FLE was found in all Hyalomma species (90.6%), as well as efficient maternal transmission of FLE (91.8%), and the localization of FLE in Malpighian tubules, ovaries, and salivary glands in H. marginatum Furthermore, we demonstrated strong cophylogeny between FLE and their host species. Contrary to FLE, the prevalence of Rickettsia ranged from 2.4% to 81.3% and was significantly different between Hyalomma species, with a higher prevalence in ticks collected from migratory birds. Using ompA gene sequences, most of the Rickettsia spp. were similar to Rickettsia aeschlimannii , while a few were similar to Rickettsia africae of the spotted fever group (SFG). Given their zoonotic importance, 249 ticks were tested for Crimean Congo hemorrhagic fever virus infection, and all were negative. The results imply that Hyalomma and FLE have obligatory symbiotic interactions, indicating a potential SFG Rickettsia zoonosis risk. A further understanding of the possible influence of FLE on Hyalomma development, as well as on its infection with Rickettsia pathogens, may lead to novel ways to control tick-borne zoonoses. IMPORTANCE This study shows that Francisella -like endosymbionts were ubiquitous in Hyalomma , were maternally transmitted, and cospeciated with their hosts. These findings imply that the interaction between FLE and Hyalomma is of an obligatory

Species Sorting of Benthic Invertebrates in a Salinity Gradient – Importance of Dispersal Limitation

PubMed Central

Josefson, Alf B.

2016-01-01

The relative importance of environment and dispersal related processes for community assembly has attracted great interest over recent decades, but few empirical studies from the marine/estuarine realm have examined the possible effects of these two types of factors in the same system. Importance of these processes was investigated in a hypothetical metacommunity of benthic invertebrates in 16 micro-tidal estuaries connected to the same open sea area. The estuaries differed in size and connectivity to the open sea and represented a salinity gradient across the estuaries. The Elements of Metacommunity Structure (EMS) approach on estuary scale was complemented with a mechanistic variance partitioning approach on sample scale to disentangle effects of factors affecting assembly of three trait groups of species with different dispersivity. A quasi-Clementsian pattern was observed for all three traits, a likely response to some latent gradient. The primary axis in the pattern was most strongly related to gradients in estuary salinity and estuary entrance width and correlation with richness indicated nestedness only in the matrix of the most dispersive trait group. In the variance partitioning approach measures of turnover and nestedness between paired samples each from different estuaries were related to environmental distance in different gradients. Distance between estuaries was unimportant suggesting importance of factors characterizing the estuaries. While the high dispersive species mainly were sorted in the salinity gradient, apparently according to their tolerance ranges towards salinity, the two less dispersive traits were additionally affected by estuary entrance width and possibly also area. The results exemplify a mechanism of community assembly in the marine realm where the niche factor salinity in conjunction with differential dispersal structure invertebrates in a metacommunity of connected estuaries, and support the idea that dispersive species are more

Sea Cucumber Glycosides: Chemical Structures, Producing Species and Important Biological Properties.

PubMed

Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Rahman, M Aminur; Islam, Mohamad Tofazzal

2017-10-17

Sea cucumbers belonging to echinoderm are traditionally used as tonic food in China and other Asian countries. They produce abundant biologically active triterpene glycosides. More than 300 triterpene glycosides have been isolated and characterized from various species of sea cucumbers, which are classified as holostane and nonholostane depending on the presence or absence of a specific structural unit γ(18,20)-lactone in the aglycone. Triterpene glycosides contain a carbohydrate chain up to six monosaccharide units mainly consisting of d-xylose, 3-O-methy-d-xylose, d-glucose, 3-O-methyl-d-glucose, and d-quinovose. Cytotoxicity is the common biological property of triterpene glycosides isolated from sea cucumbers. Besides cytotoxicity, triterpene glycosides also exhibit antifungal, antiviral and hemolytic activities. This review updates and summarizes our understanding on diverse chemical structures of triterpene glycosides from various species of sea cucumbers and their important biological activities. Mechanisms of action and structural-activity relationships (SARs) of sea cucumber glycosides are also discussed briefly.

Sea Cucumber Glycosides: Chemical Structures, Producing Species and Important Biological Properties

PubMed Central

Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Rahman, M. Aminur; Islam, Mohamad Tofazzal

2017-01-01

Sea cucumbers belonging to echinoderm are traditionally used as tonic food in China and other Asian countries. They produce abundant biologically active triterpene glycosides. More than 300 triterpene glycosides have been isolated and characterized from various species of sea cucumbers, which are classified as holostane and nonholostane depending on the presence or absence of a specific structural unit γ(18,20)-lactone in the aglycone. Triterpene glycosides contain a carbohydrate chain up to six monosaccharide units mainly consisting of d-xylose, 3-O-methy-d-xylose, d-glucose, 3-O-methyl-d-glucose, and d-quinovose. Cytotoxicity is the common biological property of triterpene glycosides isolated from sea cucumbers. Besides cytotoxicity, triterpene glycosides also exhibit antifungal, antiviral and hemolytic activities. This review updates and summarizes our understanding on diverse chemical structures of triterpene glycosides from various species of sea cucumbers and their important biological activities. Mechanisms of action and structural–activity relationships (SARs) of sea cucumber glycosides are also discussed briefly. PMID:29039760

Human myiasis in New Zealand: imported and indigenously-acquired cases: the species of concern and clinical aspects.

PubMed

Derraik, Jose G B; Heath, Allen C G; Rademaker, Marius

2010-09-10

Reports of myiasis in humans in New Zealand are somewhat rare, and little attention has been paid to this issue in the local medical literature. A number of Diptera (fly) families present in New Zealand have been associated with cases of human myiasis: Calliphoridae (7 species), Fanniidae (2 species), Muscidae (3 species), Oestridae (4 species), Phoridae (3 species), Psychodidae (1 species), Sarcophagidae (2 species), Stratiomyidae (1 species) and Syrphidae (1 species). Despite these numbers, there have only been 6 published records and we obtained further 16 unpublished reports of myiasis acquired in New Zealand. Records of imported myiasis in humans are also rare, with only 2 published and 6 unpublished cases obtained. As many medical practitioners are unaware of myiasis or encounter it rarely, we provide a brief discussion of the clinical features and treatment.

Evaluating ecoregion-based height-diameter relationships of five economically important Appalachian hardwood species in West Virginia

Treesearch

John R. Brooks; Harry V., Jr. Wiant

2007-01-01

Five economically important Appalachian hardwood species were selected from five ecoregions in West Virginia. A nonlinear extra sum of squares procedure was employed to test whether the height-diameter relationships, based on measurements from the 2000 inventory from West Virginia, were significantly different at the ecoregion level. For all species examined, the null...

Saprinus planiusculus (Motschulsky' 1849) (Coleoptera: Histeridae), a beetle species of forensic importance in Khuzetan Province, Iran.

PubMed

Fakoorziba, M R; Assareh, M; Keshavarzi, D; Soltani, A; Moemenbellah-Fard, M D; Zarenezhad, M

2017-01-01

Medico legal forensic entomology is the science and study of cadaveric arthropods related to criminal investigations. The study of beetles is particularly important in forensic cases. This can be important in determining the time of death and also obtain qualitative information about the location of the crime. The aim of this study was to introduce the Saprinus planiusculus on a rat carrion as a beetle species of forensic importance in Khuzestan province. This study was carried out using a laboratory bred rat (Wistar rat) as a model for human decomposition. The rat was killed by contusion and placed in a location adjacent to the Karun River. Observations and collections of beetles were made daily during May to July 2015. Decomposition time for rat carrion lasted 38 days and S. planiusculus was seen in the fresh to post decay stages of body decomposition and the largest number of this species caught in the decay stage. The species of beetle found in this case could be used in forensic investigations, particularly during the warm season in the future.

SNP Marker Integration and QTL Analysis of 12 Agronomic and Morphological Traits in F8 RILs of Pepper (Capsicum annuum L.)

PubMed Central

Lu, Fu-Hao; Kwon, Soon-Wook; Yoon, Min-Young; Kim, Ki-Taek; Cho, Myeong-Cheoul; Yoon, Moo-Kyung; Park, Yong-Jin

2012-01-01

Red pepper, Capsicum annuum L., has been attracting geneticists’ and breeders’ attention as one of the important agronomic crops. This study was to integrate 41 SNP markers newly developed from comparative transcriptomes into a previous linkage map, and map 12 agronomic and morphological traits into the integrated map. A total of 39 markers found precise position and were assigned to 13 linkage groups (LGs) as well as the unassigned LGe, leading to total 458 molecular markers present in this genetic map. Linkage mapping was supported by the physical mapping to tomato and potato genomes using BLAST retrieving, revealing at least two-thirds of the markers mapped to the corresponding LGs. A sum of 23 quantitative trait loci from 11 traits was detected using the composite interval mapping algorithm. A consistent interval between a035_1 and a170_1 on LG5 was detected as a main-effect locus among the resistance QTLs to Phytophthora capsici at high-, intermediate- and low-level tests, and interactions between the QTLs for high-level resistance test were found. Considering the epistatic effect, those QTLs could explain up to 98.25% of the phenotype variations of resistance. Moreover, 17 QTLs for another eight traits were found to locate on LG3, 4, and 12 mostly with varying phenotypic contribution. Furthermore, the locus for corolla color was mapped to LG10 as a marker. The integrated map and the QTLs identified would be helpful for current genetics research and crop breeding, especially in the Solanaceae family. PMID:22684870

Are Photosynthetic Characteristics and Energetic Cost Important Invasive Traits for Alien Sonneratia Species in South China?

PubMed

Li, Feng-Lan; Zan, Qi-Jie; Hu, Zheng-Yu; Shin, Paul-K S; Cheung, Siu-Gin; Wong, Yuk-Shan; Tam, Nora Fung-Yee; Lei, An-Ping

2016-01-01

A higher photosynthesis and lower energetic cost are recognized as important characteristics for invasive species, but whether these traits are also important for the ability of alien mangrove species to become invasive has seldom been reported. A microcosm study was conducted to compare the photosynthetic characteristics, energetic cost indices and other growth traits between two alien species (Sonneratia apetala and S. caseolaris) and four native mangrove species over four seasons in a subtropical mangrove nature reserve in Shenzhen, South China. The aim of the study was to evaluate the invasive potential of Sonneratia based on these physiological responses. The annual average net photosynthetic rate (Pn), stomatal conductance (Gs) and total carbon assimilation per unit leaf area (Atotal) of the two alien Sonneratia species were significantly higher than the values of the native mangroves. In contrast, the opposite results were obtained for the leaf construction cost (CC) per unit dry mass (CCM) and CC per unit area (CCA) values. The higher Atotal and lower CC values resulted in a 72% higher photosynthetic energy-use efficiency (PEUE) for Sonneratia compared to native mangroves, leading to a higher relative growth rate (RGR) of the biomass and height of Sonneratia with the respective values being 51% and 119% higher than those of the native species. Higher photosynthetic indices for Sonneratia compared to native species were found in all seasons except winter, whereas lower CC values were found in all four seasons. The present findings reveal that alien Sonneratia species may adapt well and become invasive in subtropical mangrove wetlands in Shenzhen due to their higher photosynthetic characteristics coupled with lower costs in energy use, leading to a higher PEUE. The comparison of these physiological responses between S. apetala and S. caseolaris reveal that the former species is more invasive than the latter one, thus requiring more attention in future.

Are Photosynthetic Characteristics and Energetic Cost Important Invasive Traits for Alien Sonneratia Species in South China?

PubMed Central

Li, Feng-Lan; Zan, Qi-Jie; Hu, Zheng-Yu; Shin, Paul-K. S.; Cheung, Siu-Gin; Wong, Yuk-Shan; Tam, Nora Fung-Yee; Lei, An-Ping

2016-01-01

A higher photosynthesis and lower energetic cost are recognized as important characteristics for invasive species, but whether these traits are also important for the ability of alien mangrove species to become invasive has seldom been reported. A microcosm study was conducted to compare the photosynthetic characteristics, energetic cost indices and other growth traits between two alien species (Sonneratia apetala and S. caseolaris) and four native mangrove species over four seasons in a subtropical mangrove nature reserve in Shenzhen, South China. The aim of the study was to evaluate the invasive potential of Sonneratia based on these physiological responses. The annual average net photosynthetic rate (Pn), stomatal conductance (Gs) and total carbon assimilation per unit leaf area (Atotal) of the two alien Sonneratia species were significantly higher than the values of the native mangroves. In contrast, the opposite results were obtained for the leaf construction cost (CC) per unit dry mass (CCM) and CC per unit area (CCA) values. The higher Atotal and lower CC values resulted in a 72% higher photosynthetic energy-use efficiency (PEUE) for Sonneratia compared to native mangroves, leading to a higher relative growth rate (RGR) of the biomass and height of Sonneratia with the respective values being 51% and 119% higher than those of the native species. Higher photosynthetic indices for Sonneratia compared to native species were found in all seasons except winter, whereas lower CC values were found in all four seasons. The present findings reveal that alien Sonneratia species may adapt well and become invasive in subtropical mangrove wetlands in Shenzhen due to their higher photosynthetic characteristics coupled with lower costs in energy use, leading to a higher PEUE. The comparison of these physiological responses between S. apetala and S. caseolaris reveal that the former species is more invasive than the latter one, thus requiring more attention in future. PMID

Meeting the Vitamin A Requirement: The Efficacy and Importance of β-Carotene in Animal Species

PubMed Central

2016-01-01

Vitamin A is essential for life in all vertebrate animals. Vitamin A requirement can be met from dietary preformed vitamin A or provitamin A carotenoids, the most important of which is β-carotene. The metabolism of β-carotene, including its intestinal absorption, accumulation in tissues, and conversion to vitamin A, varies widely across animal species and determines the role that β-carotene plays in meeting vitamin A requirement. This review begins with a brief discussion of vitamin A, with an emphasis on species differences in metabolism. A more detailed discussion of β-carotene follows, with a focus on factors impacting bioavailability and its conversion to vitamin A. Finally, the literature on how animals utilize β-carotene is reviewed individually for several species and classes of animals. We conclude that β-carotene conversion to vitamin A is variable and dependent on a number of factors, which are important to consider in the formulation and assessment of diets. Omnivores and herbivores are more efficient at converting β-carotene to vitamin A than carnivores. Absorption and accumulation of β-carotene in tissues vary with species and are poorly understood. More comparative and mechanistic studies are required in this area to improve the understanding of β-carotene metabolism. PMID:27833936

DNA Microarray Detection of 18 Important Human Blood Protozoan Species

PubMed Central

Chen, Jun-Hu; Feng, Xin-Yu; Chen, Shao-Hong; Cai, Yu-Chun; Lu, Yan; Zhou, Xiao-Nong; Chen, Jia-Xu; Hu, Wei

2016-01-01

Background Accurate detection of blood protozoa from clinical samples is important for diagnosis, treatment and control of related diseases. In this preliminary study, a novel DNA microarray system was assessed for the detection of Plasmodium, Leishmania, Trypanosoma, Toxoplasma gondii and Babesia in humans, animals, and vectors, in comparison with microscopy and PCR data. Developing a rapid, simple, and convenient detection method for protozoan detection is an urgent need. Methodology/Principal Findings The microarray assay simultaneously identified 18 species of common blood protozoa based on the differences in respective target genes. A total of 20 specific primer pairs and 107 microarray probes were selected according to conserved regions which were designed to identify 18 species in 5 blood protozoan genera. The positive detection rate of the microarray assay was 91.78% (402/438). Sensitivity and specificity for blood protozoan detection ranged from 82.4% (95%CI: 65.9% ~ 98.8%) to 100.0% and 95.1% (95%CI: 93.2% ~ 97.0%) to 100.0%, respectively. Positive predictive value (PPV) and negative predictive value (NPV) ranged from 20.0% (95%CI: 2.5% ~ 37.5%) to 100.0% and 96.8% (95%CI: 95.0% ~ 98.6%) to 100.0%, respectively. Youden index varied from 0.82 to 0.98. The detection limit of the DNA microarrays ranged from 200 to 500 copies/reaction, similar to PCR findings. The concordance rate between microarray data and DNA sequencing results was 100%. Conclusions/Significance Overall, the newly developed microarray platform provides a convenient, highly accurate, and reliable clinical assay for the determination of blood protozoan species. PMID:27911895

[An ADAA model and its analysis method for agronomic traits based on the double-cross mating design].

PubMed

Xu, Z C; Zhu, J

2000-01-01

According to the double-cross mating design and using principles of Cockerham's general genetic model, a genetic model with additive, dominance and epistatic effects (ADAA model) was proposed for the analysis of agronomic traits. Components of genetic effects were derived for different generations. Monte Carlo simulation was conducted for analyzing the ADAA model and its reduced AD model by using different generations. It was indicated that genetic variance components could be estimated without bias by MINQUE(1) method and genetic effects could be predicted effectively by AUP method; at least three generations (including parent, F1 of single cross and F1 of double-cross) were necessary for analyzing the ADAA model and only two generations (including parent and F1 of double-cross) were enough for the reduced AD model. When epistatic effects were taken into account, a new approach for predicting the heterosis of agronomic traits of double-crosses was given on the basis of unbiased prediction of genotypic merits of parents and their crosses. In addition, genotype x environment interaction effects and interaction heterosis due to G x E interaction were discussed briefly.

Relationship between Agronomic Parameters, Phenolic Composition of Grape Skin, and Texture Properties of Vitis vinifera L. cv. Tempranillo.

PubMed

García-Estévez, Ignacio; Andrés-García, Paula; Alcalde-Eon, Cristina; Giacosa, Simone; Rolle, Luca; Rivas-Gonzalo, Julián C; Quijada-Morín, Natalia; Escribano-Bailón, M Teresa

2015-09-09

The relationship between the agronomic parameters of grapevine and the phenolic composition of skin of Vitis vinifera L. cv. Tempranillo grapes was assessed. The physical and mechanical properties of berries and their skins were also determined and correlated to the chemical composition. Results showed a significant negative correlation between grapevine vigor-related parameters (such as leaf area and bunch weight) and anthocyanin composition, whereas the percentage (w/w) of seeds was negatively correlated with the amount of flavanols of grape skins. Texture properties of grape skins also showed an important relationship with chemical composition. Berry hardness showed a negative correlation with the coumaroyl-anthocyanin derivatives, but it was positively correlated to skin flavanic composition. Moreover, significant regressions with high coefficients of determination were found between phenolic composition and grapevine vigor-related and texture variables, thus pointing out that these parameters might be useful for estimating the phenolic composition of grape skins.

A carotenogenic mini-pathway introduced into white corn does not affect development or agronomic performance

PubMed Central

Zanga, Daniela; Capell, Teresa; Slafer, Gustavo A.; Christou, Paul; Savin, Roxana

2016-01-01

High-carotenoid corn (Carolight®) has been developed as a vehicle to deliver pro-vitamin A in the diet and thus address vitamin A deficiency in at-risk populations in developing countries. Like any other novel crop, the performance of Carolight® must be tested in different environments to ensure that optimal yields and productivity are maintained, particularly in this case to ensure that the engineered metabolic pathway does not attract a yield penalty. Here we compared the performance of Carolight® with its near isogenic white corn inbred parental line under greenhouse and field conditions, and monitored the stability of the introduced trait. We found that Carolight® was indistinguishable from its near isogenic line in terms of agronomic performance, particularly grain yield and its main components. We also established experimentally that the functionality of the introduced trait was indistinguishable when plants were grown in a controlled environment or in the field. Such thorough characterization under different agronomic conditions is rarely performed even for first-generation traits such as herbicide tolerance and pest resistance, and certainly not for complex second-generation traits such as the metabolic remodeling in the Carolight® variety. Our results therefore indicate that Carolight® can now be incorporated into breeding lines to generate hybrids with locally adapted varieties for further product development and assessment. PMID:27922071

A carotenogenic mini-pathway introduced into white corn does not affect development or agronomic performance.

PubMed

Zanga, Daniela; Capell, Teresa; Slafer, Gustavo A; Christou, Paul; Savin, Roxana

2016-12-06

High-carotenoid corn (Carolight®) has been developed as a vehicle to deliver pro-vitamin A in the diet and thus address vitamin A deficiency in at-risk populations in developing countries. Like any other novel crop, the performance of Carolight® must be tested in different environments to ensure that optimal yields and productivity are maintained, particularly in this case to ensure that the engineered metabolic pathway does not attract a yield penalty. Here we compared the performance of Carolight® with its near isogenic white corn inbred parental line under greenhouse and field conditions, and monitored the stability of the introduced trait. We found that Carolight® was indistinguishable from its near isogenic line in terms of agronomic performance, particularly grain yield and its main components. We also established experimentally that the functionality of the introduced trait was indistinguishable when plants were grown in a controlled environment or in the field. Such thorough characterization under different agronomic conditions is rarely performed even for first-generation traits such as herbicide tolerance and pest resistance, and certainly not for complex second-generation traits such as the metabolic remodeling in the Carolight® variety. Our results therefore indicate that Carolight® can now be incorporated into breeding lines to generate hybrids with locally adapted varieties for further product development and assessment.

A survey of wild plant species for food use in Sicily (Italy) - results of a 3-year study in four Regional Parks.

PubMed

Licata, Mario; Tuttolomondo, Teresa; Leto, Claudio; Virga, Giuseppe; Bonsangue, Giuseppe; Cammalleri, Ignazio; Gennaro, Maria Cristina; La Bella, Salvatore

2016-02-09

This paper illustrates the results of a study carried out in four Regional Parks of Sicily (Italy), concerning traditional knowledge on food use of wild plant species. The main aims of the paper were: (i) to verify which wild plant species are used for food purpose in the local culture based on information provided by elderly inhabitants (ii) to verify the presence of wild plant species which have not been cited for food use in previous studies in the Mediterranean area (iii) to determine how many of the most frequently cited wild plant species are cultivated by the local population in the four Sicilian Parks. Semi-structured interviews were carried out in the local communities of the four Regional Parks between 2007 and 2010. A total of 802 people over the age of 60 were interviewed. Cultural Importance Index was used to evaluate the level of importance given to any wild plant species as a food in the local culture. The level of appreciation of the wild plant species and the possible effects of wild plants on human health were also investigated. Local communities currently use a total number of 119 wild species for food purposes. Asteraceae and Brassicaceae were the most represented botanical families. In each of the four Sicilian Parks, Cichorium intybus L. and Foeniculum vulgare Mill. obtained the highest Cultural Importance Index values. Sixty-four species were indicated as also having medicinal properties. Leaves and other aerial plant parts were the parts most-used for the preparation of traditional recipes. The research shows that the level of traditional knowledge on the food uses of wild plant species in the study area is poor. The food uses of plants which are most likely to survive over time are those at the interface of food and medicine. Further agronomic studies are needed for a number of species with a view to introducing them as a crop into non-intensive agricultural systems.

Mining conifers’ mega-genome using rapid and efficient multiplexed high-throughput genotyping-by-sequencing (GBS) SNP discovery platform

USDA-ARS?s Scientific Manuscript database

Next-generation sequencing (NGS) technologies are revolutionizing both medical and biological research through generation of massive SNP data sets for identifying heritable genome variation underlying key traits, from rare human diseases to important agronomic phenotypes in crop species. We evaluate...

Single-molecule sequencing and optical mapping yields an improved genome of woodland strawberry (Fragaria vesca) with chromosome-scale contiguity

USDA-ARS?s Scientific Manuscript database

Although draft genomes are available for most agronomically important plant species, the majority are incomplete, highly fragmented, and often riddled with assembly and scaffolding errors. These assembly issues hinder advances in tool development for functional genomics and systems biology. Here we ...

Molecular identification, genetic diversity, population genetics and genomics of Rhizoctonia solani. In:perspective of plant pathology in genomic era

USDA-ARS?s Scientific Manuscript database

The basidiomycetous soilborne fungus Rhizoctonia (sensu lato) is an economically important pathogen of worldwide distribution and it is known to attack at least 188 species of higher plants, including agronomic crops, vegetables, ornamentals, forest trees and turfgrasses. The pathogenic isolates may...

Agricultural practices to improve nitrogen use efficiency through the use of arbuscular mycorrhizae: Basic and agronomic aspects.

PubMed

Verzeaux, Julien; Hirel, Bertrand; Dubois, Frédéric; Lea, Peter J; Tétu, Thierry

2017-11-01

Nitrogen cycling in agroecosystems is heavily dependent upon arbuscular mycorrhizal fungi (AMF) present in the soil microbiome. These fungi develop obligate symbioses with various host plant species, thus increasing their ability to acquire nutrients. However, AMF are particularly sensitive to physical, chemical and biological disturbances caused by human actions that limit their establishment. For a more sustainable agriculture, it will be necessary to further investigate which agricultural practices could be favorable to maximize the benefits of AMF to improve crop nitrogen use efficiency (NUE), thus reducing nitrogen (N) fertilizer usage. Direct seeding, mulch-based cropping systems prevent soil mycelium disruption and increase AMF propagule abundance. Such cropping systems lead to more efficient root colonization by AMF and thus a better establishment of the plant/fungal symbiosis. In addition, the use of continuous cover cropping systems can also enhance the formation of more efficient interconnected hyphal networks between mycorrhizae colonized plants. Taking into account both fundamental and agronomic aspects of mineral nutrition by plant/AMF symbioses, we have critically described, how improving fungal colonization through the reduction of soil perturbation and maintenance of an ecological balance could be helpful for increasing crop NUE. Copyright © 2017 Elsevier B.V. All rights reserved.

Toxicity of biosolids-derived triclosan and triclocarban to six crop species.

PubMed

Prosser, Ryan S; Lissemore, Linda; Solomon, Keith R; Sibley, Paul K

2014-08-01

Biosolids are an important source of nutrients and organic matter, which are necessary for the productive cultivation of crop plants. Biosolids have been found to contain the personal care products triclosan and triclocarban at high concentrations relative to other pharmaceuticals and personal care products. The present study investigates whether exposure of 6 plant species (radish, carrot, soybean, lettuce, spring wheat, and corn) to triclosan or triclocarban derived from biosolids has an adverse effect on seed emergence and/or plant growth parameters. Plants were grown in soil amended with biosolids at a realistic agronomic rate. Biosolids were spiked with triclosan or triclocarban to produce increasing environmentally relevant exposures. The concentration of triclosan and triclocarban in biosolids-amended soil declined by up to 97% and 57%, respectively, over the course of the experiments. Amendment with biosolids had a positive effect on the majority of growth parameters in radish, carrot, soybean, lettuce, and wheat plants. No consistent triclosan- or triclocarban-dependent trends in seed emergence and plant growth parameters were observed in 5 of 6 plant species. A significant negative trend in shoot mass was observed for lettuce plants exposed to increasing concentrations of triclocarban (p<0.001). If best management practices are followed for biosolids amendment, triclosan and triclocarban pose a negligible risk to seed emergence and growth of crop plants. © 2014 SETAC.

Designing an Accompanying Ecosystem to Foster Entrepreneurship among Agronomic and Forestry Engineering Students. Opinion and Commitment of University Lecturers

ERIC Educational Resources Information Center

Ortiz-Medina, L.; Fernández-Ahumada, E.; Lara-Vélez, P.; Taguas, E. V.; Gallardo-Cobos, R.; del Campillo, M. C.; Guerrero-Ginel, J. E.

2016-01-01

In the Higher School of Agronomic and Forestry Engineering of the University of Cordoba, a collective project conceived as an 'ecosystem to support and accompany entrepreneurs' has been proposed. The approach aims to spread and consolidate the entrepreneurial spirit and to respond to the demands of possible stakeholders involved in the whole…

Barcode Identifiers as a Practical Tool for Reliable Species Assignment of Medically Important Black Yeast Species

PubMed Central

Heinrichs, Guido; de Hoog, G. Sybren

2012-01-01

Herpotrichiellaceous black yeasts and relatives comprise severe pathogens flanked by nonpathogenic environmental siblings. Reliable identification by conventional methods is notoriously difficult. Molecular identification is hampered by the sequence variability in the internal transcribed spacer (ITS) domain caused by difficult-to-sequence homopolymeric regions and by poor taxonomic attribution of sequences deposited in GenBank. Here, we present a potential solution using short barcode identifiers (27 to 50 bp) based on ITS2 ribosomal DNA (rDNA), which allows unambiguous definition of species-specific fragments. Starting from proven sequences of ex-type and authentic strains, we were able to describe 103 identifiers. Multiple BLAST searches of these proposed barcode identifiers in GenBank revealed uniqueness for 100 taxonomic entities, whereas the three remaining identifiers each matched with two entities, but the species of these identifiers could easily be discriminated by differences in the remaining ITS regions. Using the proposed barcode identifiers, a 4.1-fold increase of 100% matches in GenBank was achieved in comparison to the classical approach using the complete ITS sequences. The proposed barcode identifiers will be made accessible for the diagnostic laboratory in a permanently updated online database, thereby providing a highly practical, reliable, and cost-effective tool for identification of clinically important black yeasts and relatives. PMID:22785187

The importance of range edges for an irruptive species during extreme weather events

USGS Publications Warehouse

Bateman, Brooke L.; Pidgeon, Anna M.; Radeloff, Volker C.; Allstadt, Andrew J.; Akçakaya, H. Resit; Thogmartin, Wayne E.; Vavrus, Stephen J.; Heglund, Patricia J.

2015-01-01

In a changing climate where more frequent extreme weather may be more common, conservation strategies for weather-sensitive species may require consideration of habitat in the edges of species’ ranges, even though non-core areas may be unoccupied in ‘normal’ years. Our results highlight the conservation importance of range edges in providing refuge from extreme events, such as drought, and climate change.

Development of RFLP-PCR method for the identification of medically important Aspergillus species using single restriction enzyme MwoI.

PubMed

Diba, K; Mirhendi, H; Kordbacheh, P; Rezaie, S

2014-01-01

In this study we attempted to modify the PCR-RFLP method using restriction enzyme MwoI for the identification of medically important Aspergillus species. Our subjects included nine standard Aspergillus species and 205 Aspergillus isolates of approved hospital acquired infections and hospital indoor sources. First of all, Aspergillus isolates were identified in the level of species by using morphologic method. A twenty four hours culture was performed for each isolates to harvest Aspergillus mycelia and then genomic DNA was extracted using Phenol-Chloroform method. PCR-RFLP using single restriction enzyme MwoI was performed in ITS regions of rDNA gene. The electrophoresis data were analyzed and compared with those of morphologic identifications. Total of 205 Aspergillus isolates included 153 (75%) environmental and 52 (25%) clinical isolates. A. flavus was the most frequently isolate in our study (55%), followed by A. niger 65(31.7%), A. fumigatus 18(8.7%), A. nidulans and A. parasiticus 2(1% each). MwoI enabled us to discriminate eight medically important Aspergillus species including A. fumigatus, A. niger, A. flavus as the most common isolated species. PCR-RFLP method using the restriction enzyme MwoI is a rapid and reliable test for identification of at least the most medically important Aspergillus species.

Development of RFLP-PCR method for the identification of medically important Aspergillus species using single restriction enzyme MwoI

PubMed Central

Diba, K.; Mirhendi, H.; Kordbacheh, P.; Rezaie, S.

2014-01-01

In this study we attempted to modify the PCR-RFLP method using restriction enzyme MwoI for the identification of medically important Aspergillus species. Our subjects included nine standard Aspergillus species and 205 Aspergillus isolates of approved hospital acquired infections and hospital indoor sources. First of all, Aspergillus isolates were identified in the level of species by using morphologic method. A twenty four hours culture was performed for each isolates to harvest Aspergillus mycelia and then genomic DNA was extracted using Phenol-Chloroform method. PCR-RFLP using single restriction enzyme MwoI was performed in ITS regions of rDNA gene. The electrophoresis data were analyzed and compared with those of morphologic identifications. Total of 205 Aspergillus isolates included 153 (75%) environmental and 52 (25%) clinical isolates. A. flavus was the most frequently isolate in our study (55%), followed by A. niger 65(31.7%), A. fumigatus 18(8.7%), A. nidulans and A. parasiticus 2(1% each). MwoI enabled us to discriminate eight medically important Aspergillus species including A. fumigatus, A. niger, A. flavus as the most common isolated species. PCR-RFLP method using the restriction enzyme MwoI is a rapid and reliable test for identification of at least the most medically important Aspergillus species. PMID:25242934

Identification of the western tarnished plant bug (lygus hesperus) olfactory co-receptor orco: expression profile and confirmation of atypical membrane topology

USDA-ARS?s Scientific Manuscript database

Lygus hesperus (western tarnished plant bug) is an agronomically important pest species of numerous cropping systems. Similar to other insects, a critical component underlying behaviors is the perception and discrimination of olfactory cues. Consequently, the molecular basis of olfaction in this spe...

Population structure and genetic basis of the agronomic traits of upland cotton in China revealed by a genome-wide association study using high-density SNPs.

PubMed

Huang, Cong; Nie, Xinhui; Shen, Chao; You, Chunyuan; Li, Wu; Zhao, Wenxia; Zhang, Xianlong; Lin, Zhongxu

2017-11-01

Gossypium hirsutum L. represents the largest source of textile fibre, and China is one of the largest cotton-producing and cotton-consuming countries in the world. To investigate the genetic architecture of the agronomic traits of upland cotton in China, a diverse and nationwide population containing 503 G. hirsutum accessions was collected for a genome-wide association study (GWAS) on 16 agronomic traits. The accessions were planted in four places from 2012 to 2013 for phenotyping. The CottonSNP63K array and a published high-density map based on this array were used for genotyping. The 503 G. hirsutum accessions were divided into three subpopulations based on 11 975 quantified polymorphic single-nucleotide polymorphisms (SNPs). By comparing the genetic structure and phenotypic variation among three genetic subpopulations, seven geographic distributions and four breeding periods, we found that geographic distribution and breeding period were not the determinants of genetic structure. In addition, no obvious phenotypic differentiations were found among the three subpopulations, even though they had different genetic backgrounds. A total of 324 SNPs and 160 candidate quantitative trait loci (QTL) regions were identified as significantly associated with the 16 agronomic traits. A network was established for multieffects in QTLs and interassociations among traits. Thirty-eight associated regions had pleiotropic effects controlling more than one trait. One candidate gene, Gh_D08G2376, was speculated to control the lint percentage (LP). This GWAS is the first report using high-resolution SNPs in upland cotton in China to comprehensively investigate agronomic traits, and it provides a fundamental resource for cotton genetic research and breeding. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Evaluation of virus resistance and agronomic performance of rice cultivar ASD 16 after transfer of transgene against Rice tungro bacilliform virus by backcross breeding.

PubMed

Valarmathi, P; Kumar, G; Robin, S; Manonmani, S; Dasgupta, I; Rabindran, R

2016-08-01

Severe losses of rice yield in south and southeast Asia are caused by Rice tungro disease (RTD) induced by mixed infection of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV). In order to develop transgene-based resistance against RTBV, one of its genes, ORF IV, was used to generate transgenic resistance based on RNA-interference in the easily transformed rice variety Pusa Basmati-1, and the transgene was subsequently introgressed to rice variety ASD 16, a variety popular in southern India, using transgene marker-assisted selection. Here, we report the evaluation of BC3F4 and BC3F5 generation rice plants for resistance to RTBV as well as for agronomic traits under glasshouse conditions. The BC3F4 and BC3F5 generation rice plants tested showed variable levels of resistance, which was manifested by an average of twofold amelioration in height reduction, 1.5-fold decrease in the reduction in chlorophyll content, and 100- to 10,000-fold reduction in the titers of RTBV, but no reduction of RTSV titers, in three backcrossed lines when compared with the ASD 16 parent. Agronomic traits of some of the backcrossed lines recorded substantial improvements when compared with the ASD 16 parental line after inoculation by RTBV and RTSV. This work represents an important step in transferring RTD resistance to a susceptible popular rice variety, hence enhancing its yield in areas threatened by the disease.

Antimicrobial activity of some important Adiantum species used traditionally in indigenous systems of medicine.

PubMed

Singh, Meenakshi; Singh, Neha; Khare, P B; Rawat, A K S

2008-01-17

Adiantum Linn. of Adiantaceae family is one of the most common and widely distributed species. Ethnomedicinally, the genus is important and popularly known as "Hansraj" in Ayurvedic System of Medicine. It has been used in cold, tumors of spleen, liver and other viscera, skin diseases, bronchitis and inflammatory diseases. It is also considered as tonic and diuretic. In the present study its four important species, i.e. Adiantum capillus-veneris, Adiantum peruvianum, Adiantum venustum and Adiantum caudatum were collected and extracted with methanol. These extracts were tested for their antimicrobial agents against five gram positive, six gram negative (including multiresistant bacteria Staphylococcus aureus) and eight fungal strains using standard microdilution assay. The maximum activity was exhibited by the methanolic extract of Adiantum venustum followed by Adiantum capillus-veneris, Adiantum peruvianum and Adiantum caudatum. The methanolic extract of Adiantum capillus-veneris had very low MIC value (0.48 microg/ml) against Escherichia coli whereas, Adiantum venustum extract against Aspergillus terreus with MIC of 0.97 microg/ml. Total phenolic constituents of Adiantum species viz. Adiantum venustum, Adiantum capillus-veneris, Adiantum peruvianum and Adiantum caudatum were 0.81% (w/w), 0.83% (w/w), 0.71% (w/w) and 0.52% (w/w), respectively (as gallic acid equivalent); implying that the observed activity could be related to the amount of phenolics.

Characterization of biochars to evaluate recalcitrance and agronomic performance.

PubMed

Enders, Akio; Hanley, Kelly; Whitman, Thea; Joseph, Stephen; Lehmann, Johannes

2012-06-01

Biochars (n=94) were found to have ash contents from 0.4% to 88.2%, volatile matter from 13.2% to 70.0%, and fixed carbon from 0% to 77.4% (w/w). Greater pyrolysis temperature for low-ash biochars increased fixed carbon, but decreased it for biochars with more than 20% ash. Nitrogen recovery varied depending on feedstock used to a greater extent (12-68%) than organic (25-45%) or total C (41-76%) at a pyrolysis temperature of 600 °C. Fixed carbon production ranged from no enrichment in poultry biochar to a 10-fold increase in corn biochar (at 600 °C). Prediction of biochar stability was improved by a combination of volatile matter and H:C ratios corrected for inorganic C. In contrast to stability, agronomic utility of biochars is not an absolute value, as it needs to meet local soil constraints. Woody feedstock demonstrated the greatest versatility with pH values ranging from 4 to 9. Copyright © 2012 Elsevier Ltd. All rights reserved.

A haplotype map of genomic variations and genome-wide association studies of agronomic traits in foxtail millet (Setaria italica).

PubMed

Jia, Guanqing; Huang, Xuehui; Zhi, Hui; Zhao, Yan; Zhao, Qiang; Li, Wenjun; Chai, Yang; Yang, Lifang; Liu, Kunyan; Lu, Hengyun; Zhu, Chuanrang; Lu, Yiqi; Zhou, Congcong; Fan, Danlin; Weng, Qijun; Guo, Yunli; Huang, Tao; Zhang, Lei; Lu, Tingting; Feng, Qi; Hao, Hangfei; Liu, Hongkuan; Lu, Ping; Zhang, Ning; Li, Yuhui; Guo, Erhu; Wang, Shujun; Wang, Suying; Liu, Jinrong; Zhang, Wenfei; Chen, Guoqiu; Zhang, Baojin; Li, Wei; Wang, Yongfang; Li, Haiquan; Zhao, Baohua; Li, Jiayang; Diao, Xianmin; Han, Bin

2013-08-01

Foxtail millet (Setaria italica) is an important grain crop that is grown in arid regions. Here we sequenced 916 diverse foxtail millet varieties, identified 2.58 million SNPs and used 0.8 million common SNPs to construct a haplotype map of the foxtail millet genome. We classified the foxtail millet varieties into two divergent groups that are strongly correlated with early and late flowering times. We phenotyped the 916 varieties under five different environments and identified 512 loci associated with 47 agronomic traits by genome-wide association studies. We performed a de novo assembly of deeply sequenced genomes of a Setaria viridis accession (the wild progenitor of S. italica) and an S. italica variety and identified complex interspecies and intraspecies variants. We also identified 36 selective sweeps that seem to have occurred during modern breeding. This study provides fundamental resources for genetics research and genetic improvement in foxtail millet.

Agronomic characterization of the Argentina Indicator Region. [U.S. corn belt and Argentine pampas

NASA Technical Reports Server (NTRS)

Hicks, D. R. (Principal Investigator)

1982-01-01

An overview of the Argentina indicator region including information on topography, climate, soils and vegetation is presented followed by a regionalization of crop livestock land use. Corn/soybean production and exports as well as agricultural practices are discussed. Similarities and differences in the physical agronomic scene, crop livestock land use and agricultural practices between the U.S. corn belt and the Argentine pampa are considered. The Argentine agricultural economy is described. Crop calendars for the Argentina indicator region, an accompanying description, notes on crop-livestock zones, wheat production, field size, and agricultural problems and practices are included.

A report on identification of sequence polymorphism in barcode region of six commercially important Cymbopogon species.

PubMed

Bishoyi, Ashok Kumar; Kavane, Aarti; Sharma, Anjali; Geetha, K A

2017-02-01

CYMBOPOGON: is an important member of grass family Poaceae, cultivated for essential oils which have greater medicinal and industrial value. Taxonomic identification of Cymbopogon species is determined mainly by morphological markers, odour of essential oils and concentration of bioactive compounds present in the oil matrices which are highly influenced by environment. Authenticated molecular marker based taxonomical identification is also lacking in the genus; hence effort was made to evaluate potential DNA barcode loci in six commercially important Cymbopogon species for their individual discrimination and authentication at the species level. Four widely used DNA barcoding regions viz., ITS 1 & ITS 2 spacers, matK, psbA-trnH and rbcL were taken for the study. Gene sequences of the same or related genera of the concerned loci were mined from NCBI domain and primers were designed and validated for barcode loci amplification. Out of the four loci studied, sequences from matK and ITS spacer loci revealed 0.46% and 5.64% nucleotide sequence diversity, respectively whereas the other two loci i.e., psbA-trnH and rbcL showed 100% sequence homology. The newly developed primers can be used for barcode loci amplification in the genus Cymbopogon. The identified Single Nucleotide Polymorphisms from the studied sequences may be used as barcodes for the six Cymbopogon species. The information generated can also be utilized for barcode development of the genus by including more number of Cymbopgon species in future.

Molecular confirmation of Gossypium hirsutum chromosome substitution lines and interspecific F1 hypoaneuploids

USDA-ARS?s Scientific Manuscript database

The tetraploid Gossypium species G. barbadense, G. tomentosum, and G. mustelinum (2n=52) are useful sources of important genes for pest and disease resistance, and for improved agronomic and fiber traits in Upland cotton (G. hirsutum). Cytological analyses of hybrids and comparative linkage mapping...

Relating xylem cavitation to gas exchange in cotton

USDA-ARS?s Scientific Manuscript database

Acoustic emissions (AEs) from xylem cavitation events are characteristic of transpiration processes. Though a body of work using AE exists with a large number of species, cotton and other agronomically important crops have either not been investigated, or limited information exists. The objective of...

Relating xylem cavitation to transpiration in cotton

USDA-ARS?s Scientific Manuscript database

Acoustic emmisions (AEs) from xylem cavitation events are characteristic of transpiration processes. Even though a body of work employing AE exists with a large number of species, cotton and other agronomically important crops have either not been investigated, or limited information exists. A few s...

Maize yield gaps caused by non-controllable, agronomic, and socioeconomic factors in a changing climate of Northeast China.

PubMed

Liu, Zhijuan; Yang, Xiaoguang; Lin, Xiaomao; Hubbard, Kenneth G; Lv, Shuo; Wang, Jing

2016-01-15

Closing the gap between current and potential yields is one means of increasing agricultural production to feed the globally increasing population. Therefore, investigation of the geographic patterns, trends and causes of crop yield gaps is essential to identifying where yields might be increased and quantifying the contributions of yield-limiting factors that may provide us potentials to enhance crop productivity. In this study, the changes in potential yields, attainable yields, potential farmers' yields, and actual farmers' yields during the past five decades in Northeast China (NEC) were investigated. Additionally the yield gaps caused by non-controllable, agronomic, and socioeconomic factors were determined. Over the period 1961 to 2010 the estimated regional area-weighted mean maize potential yield, attainable yield, and potential farmers' yield were approximately 12.3 t ha(-1), 11.5 t ha(-1), and 6.4 t ha(-1) which showed a decreasing tendency. The actual farmers' yield over NEC was 4.5 t ha(-1), and showed a tendency to increase (p<0.01) by 1.27 t ha(-1) per decade. The regional mean total yield gap (YGt), weighted by the area in each county dedicated to maize crop, was 64% of potential yield. Moreover, 8, 40, and 16% reductions in potential yields were due to non-controllable factors (YGI), agronomic factors (YGII), and socioeconomic factors (YGIII), respectively. Therefore, the exploitable yield gap, considered here as the difference between the potential yield and what one can expect considering non-controllable factors (i.e. YGt-YGI), of maize in NEC was about 56%. The regional area-weighted averages of YGt, and YGIII were found to have significant decreases of 11.0, and 10.7% per decade. At the time horizon 2010, the exploitable yield gaps were estimated to equal 36% of potential yield. This led to the conclusion that the yield gap could be deeply reduced by improving local agronomic management and controlling socioeconomic factors. Copyright © 2015

Molecular and Morpho-Agronomical Characterization of Root Architecture at Seedling and Reproductive Stages for Drought Tolerance in Wheat

PubMed Central

Vinod; Naik, Bhojaraja K.; Chand, Suresh; Deshmukh, Rupesh; Mallick, Niharika; Singh, Sanjay; Singh, Nagendra Kumar; Tomar, S. M. S.

2016-01-01

Water availability is a major limiting factor for wheat (Triticum aestivum L.) production in rain-fed agricultural systems worldwide. Root architecture is important for water and nutrition acquisition for all crops, including wheat. A set of 158 diverse wheat genotypes of Australian (72) and Indian (86) origin were studied for morpho-agronomical traits in field under irrigated and drought stress conditions during 2010–11 and 2011-12.Out of these 31 Indian wheat genotypes comprising 28 hexaploid (Triticum aestivum L.) and 3 tetraploid (T. durum) were characterized for root traits at reproductive stage in polyvinyl chloride (PVC) pipes. Roots of drought tolerant genotypes grew upto137cm (C306) as compared to sensitive one of 63cm with a mean value of 94.8cm. Root architecture traits of four drought tolerant (C306, HW2004, HD2888 and NI5439) and drought sensitive (HD2877, HD2012, HD2851 and MACS2496) genotypes were also observed at 6 and 9 days old seedling stage. The genotypes did not show any significant variation for root traits except for longer coleoptiles and shoot and higher absorptive surface area in drought tolerant genotypes. The visible evaluation of root images using WinRhizo Tron root scanner of drought tolerant genotype HW2004 indicated compact root system with longer depth while drought sensitive genotype HD2877 exhibited higher horizontal root spread and less depth at reproductive stage. Thirty SSR markers were used to study genetic variation which ranged from 0.12 to 0.77 with an average value of 0.57. The genotypes were categorized into three subgroups as highly tolerant, sensitive, moderately sensitive and tolerant as intermediate group based on UPGMA cluster, STRUCTURE and principal coordinate analyses. The genotypic clustering was positively correlated to grouping based on root and morpho-agronomical traits. The genetic variability identified in current study demonstrated these traits can be used to improve drought tolerance and association

Importance of hybridization between indigenous and nonindigenous freshwater species: an overlooked threat to North American biodiversity.

PubMed

Perry, William L; Lodge, David M; Feder, Jeffrey L

2002-04-01

Biodiversity of North American freshwaters is among the greatest in the world. However, due to extensive habitat degradation, pollution, and introductions of nonindigenous species, this biodiversity is also among the most endangered. Unlike habitat degradation and pollution, nonindigenous species represent a permanent loss of biodiversity because their removal or control is often impossible. Most species introduced into nonnative North American ranges, however, are not from Eurasia but have been introduced from geographically isolated regions within North America. Although the ecological effects of introduced species have been widely documented, the effects of hybridization, especially between closely related species, represents an equally serious mechanism of extinction but is much less studied. Identification of which species are likely to hybridize after contact is of critical importance to prevent the further loss of native species. Molecular phylogenetics serves as a powerful tool to identify freshwater species at risk of introgression, if we can assume that genetic distance is a good predictor of the potential for hybridization. Although not a thorough review of all cases of hybridization, this article documents the extent and effects of hybridization in fishes, crayfishes, mussels, and other invertebrates in light of the currently accepted phylogenetic relationships. We suggest this approach may be the first step in addressing the potential threat of hybridization between many of the closely related species in North American fresh waters.

New species, hyper-diversity and potential importance of Calonectria spp. from Eucalyptus in South China

PubMed Central

Lombard, L.; Chen, S.F.; Mou, X.; Zhou, X.D.; Crous, P.W.; Wingfield, M.J.

2015-01-01

Plantation forestry is expanding rapidly in China to meet an increasing demand for wood and pulp products globally. Fungal pathogens including species of Calonectria represent a serious threat to the growth and sustainability of this industry. Surveys were conducted in the Guangdong, Guangxi and Hainan Provinces of South China, where Eucalyptus trees in plantations or cuttings in nurseries displayed symptoms of leaf blight. Isolations from symptomatic leaves and soils collected close to infected trees resulted in a large collection of Calonectria isolates. These isolates were identified using the Consolidated Species Concept, employing morphological characters and DNA sequence comparisons for the β-tubulin, calmodulin, histone H3 and translation elongation factor 1-alpha gene regions. Twenty-one Calonectria species were identified of which 18 represented novel taxa. Of these, 12 novel taxa belonged to Sphaero-Naviculate Group and the remaining six to the Prolate Group. Southeast Asia appears to represent a centre of biodiversity for the Sphaero-Naviculate Group and this fact could be one of the important constraints to Eucalyptus forestry in China. The remarkable diversity of Calonectria species in a relatively small area of China and associated with a single tree species is surprising. PMID:26955194

Prediction of industrial tomato hybrids from agronomic traits and ISSR molecular markers.

PubMed

Figueiredo, A S T; Resende, J T V; Faria, M V; Da-Silva, P R; Fagundes, B S; Morales, R G F

2016-05-13

Heterosis is a highly relevant phenomenon in plant breeding. This condition is usually established in hybrids derived from crosses of highly divergent parents. The success of a breeder in obtaining heterosis is directly related to the correct identification of genetically contrasting parents. Currently, the diallel cross is the most commonly used methodology to detect contrasting parents; however, it is a time- and cost-consuming procedure. Therefore, new tools capable of performing this task quickly and accurately are required. Thus, the purpose of this study was to estimate the genetic divergence in industrial tomato lines, based on agronomic traits, and to compare with estimates obtained using inter-simple sequence repeat (ISSR) molecular markers. The genetic divergence among 10 industrial tomato lines, based on nine morphological characters and 12 ISSR primers was analyzed. For data analysis, Pearson and Spearman correlation coefficients were calculated between the genetic dissimilarity measures estimated by Mahalanobis distance and Jaccard's coefficient of genetic dissimilarity from the heterosis estimates, combining ability, and means of important traits of industrial tomato. The ISSR markers efficiently detected contrasting parents for hybrid production in tomato. Parent RVTD-08 was indicated as the most divergent, both by molecular and morphological markers, that positively contributed to increased heterosis and by the specific combining ability in the crosses in which it participated. The genetic dissimilarity estimated by ISSR molecular markers aided the identification of the best hybrids of the experiment in terms of total fruit yield, pulp yield, and soluble solids content.

Generation of amphidiploids from hybrids of wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum as a source of genetic variation for wheat improvement.

PubMed

Nemeth, Csilla; Yang, Cai-yun; Kasprzak, Paul; Hubbart, Stella; Scholefield, Duncan; Mehra, Surbhi; Skipper, Emma; King, Ian; King, Julie

2015-02-01

We aim to improve diversity of domesticated wheat by transferring genetic variation for important target traits from related wild and cultivated grass species. The present study describes the development of F1 hybrids between wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum and production of new amphidiploids. Amphidiploid lines were produced from 20 different distant relatives. Both colchicine and caffeine were successfully used to double the chromosome numbers. The genomic constitution of the newly formed amphidiploids derived from seven distant relatives was determined using genomic in situ hybridization (GISH). Altogether, 42 different plants were analysed, 19 using multicolour GISH separating the chromosomes from the A, B, and D genomes of wheat, as well as the distant relative, and 23 using single colour GISH. Restructuring of the allopolyploid genome, both chromosome losses and aneuploidy, was detected in all the genomes contained by the amphidiploids. From the observed chromosome numbers there is an indication that in amphidiploids the B genome of wheat suffers chromosome losses less frequently than the other wheat genomes. Phenotyping to realize the full potential of the wheat-related grass germplasm is underway, linking the analyzed genotypes to agronomically important target traits.

Montane and coastal species diversification in the economically important Mexican grasshopper genus Sphenarium (Orthoptera: Pyrgomorphidae).

PubMed

Pedraza-Lara, Carlos; Barrientos-Lozano, Ludivina; Rocha-Sánchez, Aurora Y; Zaldívar-Riverón, Alejandro

2015-03-01

The genus Sphenarium (Pyrgomorphidae) is a small group of grasshoppers endemic to México and Guatemala that are economically and culturally important both as a food source and as agricultural pests. However, its taxonomy has been largely neglected mainly due to its conserved interspecific external morphology and the considerable intraspecific variation in colour pattern of some taxa. Here we examined morphological as well as mitochondrial and nuclear DNA sequence data to assess the species boundaries and evolutionary history in Sphenarium. Our morphological identification and DNA sequence-based species delimitation, carried out with three different approaches (DNA barcoding, general mixed Yule-coalescent model, Bayesian species delimitation), all recovered a higher number of putative species of Sphenarium than previously recognised. We unambiguously delimit seven species, and between five and ten additional species depending on the data/method analysed. Phylogenetic relationships within the genus strongly support two main clades, one exclusively montane, the other coastal. Divergence time estimates suggest late Miocene to Pliocene ages for the origin and most of the early diversification events in the genus, which were probably influenced by the formation of the Trans-Mexican Volcanic Belt. A series of Pleistocene events could have led to the current species diversification in both montane and coastal regions. This study not only reveals an overlooked species richness for the most popular edible insect in Mexico, but also highlights the influence of the dynamic geological and climatic history of the region in shaping its current diversity. Copyright © 2015 Elsevier Inc. All rights reserved.

Observations on morphology of immature Lucilia porphyrina (Diptera: Calliphoridae), a fly species of forensic importance.

PubMed

Klong-Klaew, Tunwadee; Sukontason, Kom; Sribanditmongkol, Pongruk; Moophayak, Kittikhun; Sanit, Sangob; Sukontason, Kabkaew L

2012-11-01

Lucilia porphyrina (Walker) is a blow fly of forensic importance, and shares its geographical distribution with a related forensically important species, Lucilia cuprina (Wiedemann). The immature stages of both species are similar in general appearance; therefore, correct identification should be given special consideration. This study highlighted the main features of L. porphyrina larvae, as observed under light microscopy and scanning electron microscopy. Particular attention is given to the anterior and posterior spiracles, cephalopharyngeal skeleton, and characteristics of the dorsal spines between the prothorax and mesothorax. In the third instar specifically, morphological information on L. porphyrina showed several features that are shared by L. cuprina, and therefore need certain identification to distinguish between them. Such key features are (1) greater posterior spiracle, (2) apparent inner projection between the middle and lower slits of the posterior spiracle, and (3) strongly sclerotized peritreme. The number of papillae on the anterior spiracle may be a supplement, five to nine and three to six in L. porphyrina and L. cuprina, respectively. The key for identifying third instar of forensically important flies in Thailand has been updated to include L. porphyrina.

Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

PubMed

Husáková, Iveta; Münzbergová, Zuzana

2014-01-01

In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

Agronomic performance of new open pollinated experimental lines of broccoli (Brassica oleracea L. var. italica) evaluated under organic farming.

PubMed

Sahamishirazi, Samira; Moehring, Jens; Zikeli, Sabine; Fleck, Michael; Claupein, Wilhelm; Graeff-Hoenninger, Simone

2018-01-01

In order to develop new open pollinating cultivars of broccoli for organic farming, two experiments were conducted during fall 2015 and spring 2016. This study was aimed at comparing the agronomic performance of eleven new open pollinating breeding lines of broccoli to introduce new lines and to test their seasonal suitability for organic farming. Field experiments were carried out at the organic research station Kleinhohenheim of the University of Hohenheim (Stuttgart-Germany). Different agronomic traits total biomass fresh weight, head fresh weight, head diameter, hollow-stem, fresh weight harvest index and marketable yield were assessed together with commercial control cultivars. The data from both experiments were analyzed using a two-stage mixed model approach. In our study, genotype, growing season and their interaction had significant effects on most traits. Plants belonging to the fall growing season had bigger sizes in comparison to spring with significantly (p< 0.0001) higher biomass fresh weight. Some experimental lines had significant lower head fresh weight in spring in comparison to the fall season. The high temperature during the harvest period for the spring season affected the yield negatively through decreasing the firmness of broccoli heads. The low average minimum temperatures during the spring growing season lead to low biomass fresh weight but high fresh weight harvest index. Testing the seasonal suitability of all open pollinating lines showed that the considered fall season was better for broccoli production. However, the change in yield between the fall and the spring growing season was not significant for "Line 701" and "CHE-MIC". Considering the expression of different agronomic traits, "CHE-GRE-G", "Calinaro" and "CAN-SPB" performed the best in the fall growing season, and "CHE-GRE-G", "CHE-GRE-A", "CHE-BAL-A" and "CHE-MIC" and "Line 701" were best in the spring growing season, specifically due to the highest marketable yield and

Agronomic performance of new open pollinated experimental lines of broccoli (Brassica oleracea L. var. italica) evaluated under organic farming

PubMed Central

Moehring, Jens; Zikeli, Sabine; Fleck, Michael; Claupein, Wilhelm; Graeff-Hoenninger, Simone

2018-01-01

In order to develop new open pollinating cultivars of broccoli for organic farming, two experiments were conducted during fall 2015 and spring 2016. This study was aimed at comparing the agronomic performance of eleven new open pollinating breeding lines of broccoli to introduce new lines and to test their seasonal suitability for organic farming. Field experiments were carried out at the organic research station Kleinhohenheim of the University of Hohenheim (Stuttgart-Germany). Different agronomic traits total biomass fresh weight, head fresh weight, head diameter, hollow-stem, fresh weight harvest index and marketable yield were assessed together with commercial control cultivars. The data from both experiments were analyzed using a two-stage mixed model approach. In our study, genotype, growing season and their interaction had significant effects on most traits. Plants belonging to the fall growing season had bigger sizes in comparison to spring with significantly (p< 0.0001) higher biomass fresh weight. Some experimental lines had significant lower head fresh weight in spring in comparison to the fall season. The high temperature during the harvest period for the spring season affected the yield negatively through decreasing the firmness of broccoli heads. The low average minimum temperatures during the spring growing season lead to low biomass fresh weight but high fresh weight harvest index. Testing the seasonal suitability of all open pollinating lines showed that the considered fall season was better for broccoli production. However, the change in yield between the fall and the spring growing season was not significant for “Line 701” and “CHE-MIC”. Considering the expression of different agronomic traits, “CHE-GRE-G”, “Calinaro” and “CAN-SPB” performed the best in the fall growing season, and “CHE-GRE-G”, “CHE-GRE-A”, “CHE-BAL-A” and “CHE-MIC” and “Line 701” were best in the spring growing season, specifically due to

Hidden species diversity in Sylvirana nigrovittata (Amphibia: Ranidae) highlights the importance of taxonomic revisions in biodiversity conservation

PubMed Central

Stuart, Bryan L.

2018-01-01

Accurately delimiting species and their geographic ranges is imperative for conservation, especially in areas experiencing rapid habitat loss. Southeast Asia currently has one of the highest rates of deforestation in the world, is home to multiple biodiversity hotspots, and the majority of its countries have developing economies with limited resources for biodiversity conservation. Thus, accurately delimiting species and their ranges is particularly important in this region. We examined genetic and morphological variation in the widespread frog species Sylvirana nigrovittata (and its long-treated junior synonym S. mortenseni) with the goal of clarifying its taxonomic content and geographic range boundaries for conservation. We present evidence that the current concept of S. nigrovittata contains at least eight species, two of which are each known from only two localities, but that S. mortenseni is more geographically widespread than currently realized. Five of these species are described as new to science. PMID:29538432

Identification of QTL and Qualitative Trait Loci for Agronomic Traits Using SNP Markers in the Adzuki Bean.

PubMed

Li, Yuan; Yang, Kai; Yang, Wei; Chu, Liwei; Chen, Chunhai; Zhao, Bo; Li, Yisong; Jian, Jianbo; Yin, Zhichao; Wang, Tianqi; Wan, Ping

2017-01-01

The adzuki bean ( Vigna angularis ) is an important grain legume. Fine mapping of quantitative trait loci (QTL) and qualitative trait genes plays an important role in gene cloning, molecular-marker-assisted selection (MAS), and trait improvement. However, the genetic control of agronomic traits in the adzuki bean remains poorly understood. Single-nucleotide polymorphisms (SNPs) are invaluable in the construction of high-density genetic maps. We mapped 26 agronomic QTLs and five qualitative trait genes related to pigmentation using 1,571 polymorphic SNP markers from the adzuki bean genome via restriction-site-associated DNA sequencing of 150 members of an F 2 population derived from a cross between cultivated and wild adzuki beans. We mapped 11 QTLs for flowering time and pod maturity on chromosomes 4, 7, and 10. Six 100-seed weight (SD100WT) QTLs were detected. Two major flowering time QTLs were located on chromosome 4, firstly VaFld4.1 (PEVs 71.3%), co-segregating with SNP marker s690-144110, and VaFld4.2 (PEVs 67.6%) at a 0.974 cM genetic distance from the SNP marker s165-116310. Three QTLs for seed number per pod ( Snp3.1, Snp3.2 , and Snp4.1 ) were mapped on chromosomes 3 and 4. One QTL VaSdt4.1 of seed thickness (SDT) and three QTLs for branch number on the main stem were detected on chromosome 4. QTLs for maximum leaf width (LFMW) and stem internode length were mapped to chromosomes 2 and 9, respectively. Trait genes controlling the color of the seed coat, pod, stem and flower were mapped to chromosomes 3 and 1. Three candidate genes, VaAGL, VaPhyE , and VaAP2 , were identified for flowering time and pod maturity. VaAGL encodes an agamous-like MADS-box protein of 379 amino acids. VaPhyE encodes a phytochrome E protein of 1,121 amino acids. Four phytochrome genes ( VaPhyA1, VaPhyA2, VaPhyB , and VaPhyE ) were identified in the adzuki bean genome. We found candidate genes VaAP2/ERF.81 and VaAP2/ERF.82 of SD100WT, VaAP2-s4 of SDT, and VaAP2/ERF.86 of LFMW. A

Functional importance of GLP-1 receptor species and expression levels in cell lines.

PubMed

Knudsen, Lotte Bjerre; Hastrup, Sven; Underwood, Christina Rye; Wulff, Birgitte Schjellerup; Fleckner, Jan

2012-04-10

Of the mammalian species, only the GLP-1 receptors of rat and human origin have been described and characterized. Here, we report the cloning of the homologous GLP-1 receptors from mouse, rabbit, pig, cynomolgus monkey and chimp. The GLP-1 receptor is highly conserved across species, thus underlining the physiological importance of the peptide hormone and its receptor across a wide range of mammals. We expressed the receptors by stable transfection of BHK cells, both in cell lines with high expression levels of the cloned receptors, as well as in cell lines with lower expression levels, more comparable to endogenous expression of these receptors. High expression levels of cloned GLP-1 receptors markedly increased the potency of GLP-1 and other high affinity ligands, whereas the K(d) values were not affected. For a low affinity ligand like the ago-allosteric modulator Compound 2, expression levels of the human GLP-1 receptor were important for maximal efficacy as well as potency. The two natural metabolites of GLP-1, GLP-1(9-37) and GLP-1(9-36)amide were agonists when tested on a cell line with high expression of the recombinant human GLP-1 receptor, whereas they behaved as (low potent) antagonists on a cell line that expressed the receptor endogenously, as well as cells expressing a moderate level of the recombinant human GLP-1 receptor. The amide form was a more potent agonist than the free acid from. In conclusion, receptor expression level is an important parametre for selecting cell lines with cloned GLP-1 receptors for functional characterization of physiological and pharmaceutical ligands. Copyright © 2011 Elsevier B.V. All rights reserved.

An updated checklist of the Culicidae (Diptera) of Morocco, with notes on species of historical and current medical importance.

PubMed

Trari, Bouchra; Dakki, Mohamed; Harbach, Ralph E

2017-06-01

An updated checklist of the mosquito species (Diptera: Culicidae) recorded in Morocco from 1916 to 2016 is provided, including synonyms and synonymous usage for each species. Forty-three species belonging to seven genera are recorded so far: Anopheles (9), Aedes (12) Coquillettidia (2), Culex (12), Culiseta (5), Orthopodomyia (1) and Uranotaenia (2). Traditional and equivalent names in the polyphyletic concept of Aedes are provided for the aedine species. The historical importance and current potential threat of mosquitoes to human health in Morocco is reviewed. © 2017 The Society for Vector Ecology.

Bacterial endophyte communities of three agricultural important grass species differ in their response towards management regimes

NASA Astrophysics Data System (ADS)

Wemheuer, Franziska; Kaiser, Kristin; Karlovsky, Petr; Daniel, Rolf; Vidal, Stefan; Wemheuer, Bernd

2017-01-01

Endophytic bacteria are critical for plant growth and health. However, compositional and functional responses of bacterial endophyte communities towards agricultural practices are still poorly understood. Hence, we analyzed the influence of fertilizer application and mowing frequency on bacterial endophytes in three agriculturally important grass species. For this purpose, we examined bacterial endophytic communities in aerial plant parts of Dactylis glomerata L., Festuca rubra L., and Lolium perenne L. by pyrotag sequencing of bacterial 16S rRNA genes over two consecutive years. Although management regimes influenced endophyte communities, observed responses were grass species-specific. This might be attributed to several bacteria specifically associated with a single grass species. We further predicted functional profiles from obtained 16S rRNA data. These profiles revealed that predicted abundances of genes involved in plant growth promotion or nitrogen metabolism differed between grass species and between management regimes. Moreover, structural and functional community patterns showed no correlation to each other indicating that plant species-specific selection of endophytes is driven by functional rather than phylogenetic traits. The unique combination of 16S rRNA data and functional profiles provided a holistic picture of compositional and functional responses of bacterial endophytes in agricultural relevant grass species towards management practices.

Isozyme and allozyme markers distinguishing two morphologically similar, medically important Mastomys species (Rodentia: Muridae)

PubMed Central

Smit, Andre A; Van der Bank, Herman FH

2001-01-01

Background Two common southern African mice species, Mastomys coucha and M. natalensis, are widely distributed throughout the subregion and overlap in many areas. They also share a high degree of morphological similarity, making them impossible to distinguish in the field at present. These multimammate mice are documented carriers of serious disease vectors causing Lassa fever, plague and encephalomyocarditis, which coupled to their cohabitation with humans in many areas, could pose a significant health risk. A preliminary study reported the presence of isozyme markers at three loci (GPI-2, PT-2, -3) in one population each of M. coucha and M. natalensis. Two additional populations (from the Vaal Dam and Richards Bay) were sampled to determine the reliability of these markers, and to seek additional genetic markers. Results Fifteen proteins or enzymes provided interpretable results at a total of 39 loci. Additional fixed allele differences between the species were detected at AAT-1, ADH, EST-1, PGD-1, Hb-1 and -2. Average heterozygosities for M. coucha and M. natalensis were calculated as 0.018 and 0.032 respectively, with a mean genetic distance between the species of 0.26. Conclusions The confirmation of the isozyme and the detection of the additional allozyme markers are important contributions to the identification of these two medical and agricultural pest species. PMID:11696236

Agronomic, chemical and genetic profiles of hot peppers (Capsicum annuum ssp.).

PubMed

De Masi, Luigi; Siviero, Pietro; Castaldo, Domenico; Cautela, Domenico; Esposito, Castrese; Laratta, Bruna

2007-08-01

A study on morphology, productive yield, main quality parameters and genetic variability of eight landraces of hot pepper (Capsicum annuum ssp.) from Southern Italy has been performed. Morphological characters of berries and productivity values were evaluated by agronomic analyses. Chemical and genetic investigations were performed by HPLC and random amplified polymorphic DNA (RAPD)-PCR, respectively. In particular, carotenoid and capsaicinoid (pungency) contents were considered as main quality parameters of hot pepper. For the eight selected samples, genetic similarity values were calculated from the generated RAPD fragments and a dendrogram of genetic similarity was constructed. All the eight landraces exhibited characteristic RAPD patterns that allowed their characterization. Agro-morphological and chemical determinations were found to be adequate for selection, but they resulted useful only for plants grown in the same environmental conditions. RAPD application may provide a more reliable way based on DNA identification. The results of our study led to the identification of three noteworthy populations, suitable for processing, which fitted into different clusters of the dendrogram.

Conditions Promoting Mycorrhizal Parasitism Are of Minor Importance for Competitive Interactions in Two Differentially Mycotrophic Species

PubMed Central

Friede, Martina; Unger, Stephan; Hellmann, Christine; Beyschlag, Wolfram

2016-01-01

Interactions of plants with arbuscular mycorrhizal fungi (AMF) may range along a broad continuum from strong mutualism to parasitism, with mycorrhizal benefits received by the plant being determined by climatic and edaphic conditions affecting the balance between carbon costs vs. nutritional benefits. Thus, environmental conditions promoting either parasitism or mutualism can influence the mycorrhizal growth dependency (MGD) of a plant and in consequence may play an important role in plant-plant interactions. In a multifactorial field experiment we aimed at disentangling the effects of environmental and edaphic conditions, namely the availability of light, phosphorus and nitrogen, and the implications for competitive interactions between Hieracium pilosella and Corynephorus canescens for the outcome of the AMF symbiosis. Both species were planted in single, intraspecific and interspecific combinations using a target-neighbor approach with six treatments distributed along a gradient simulating conditions for the interaction between plants and AMF ranking from mutualistic to parasitic. Across all treatments we found mycorrhizal association of H. pilosella being consistently mutualistic, while pronounced parasitism was observed in C. canescens, indicating that environmental and edaphic conditions did not markedly affect the cost:benefit ratio of the mycorrhizal symbiosis in both species. Competitive interactions between both species were strongly affected by AMF, with the impact of AMF on competition being modulated by colonization. Biomass in both species was lowest when grown in interspecific competition, with colonization being increased in the less mycotrophic C. canescens, while decreased in the obligate mycotrophic H. pilosella. Although parasitism-promoting conditions negatively affected MGD in C. canescens, these effects were small as compared to growth decreases related to increased colonization levels in this species. Thus, the lack of plant control over

DNA-based identification of forensically important species of Sarcophagidae (Insecta: Diptera) from Rio de Janeiro, Brazil.

PubMed

Napoleão, K S; Mello-Patiu, C A; Oliveira-Costa, J; Takiya, D M; Silva, R; Moura-Neto, R S

2016-05-06

Sarcophagidae, or flesh flies, are of great importance in forensic entomology, but their effective application requires precise taxonomic identification, which relies almost exclusively on characteristics of the male genitalia. Given that female flies and larvae are most abundant in animal carcasses or on corpses, precise morphological identification can be difficult; therefore, DNA sequencing can be an additional tool for use in taxonomic identification. This paper analyzes part of the mitochondrial cytochrome c oxidase subunit I (COI) gene from three Sarcophagidae species of forensic importance in the City of Rio de Janeiro: Oxysarcodexia fluminensis, Peckia chrysostoma, and Peckia intermutans. COI fragments of 400 bp from 36 specimens of these three species were sequenced. No intraspecific differences were found among specimens of O. fluminensis, but P. chrysostoma and P. intermutans each had two haplotypes, ranging from 0 to 0.7%. The interspecific divergence was 8.5-11.6%, corroborating previously reported findings.

Plastid genomics in horticultural species: importance and applications for plant population genetics, evolution, and biotechnology

PubMed Central

Rogalski, Marcelo; do Nascimento Vieira, Leila; Fraga, Hugo P.; Guerra, Miguel P.

2015-01-01

During the evolution of the eukaryotic cell, plastids, and mitochondria arose from an endosymbiotic process, which determined the presence of three genetic compartments into the incipient plant cell. After that, these three genetic materials from host and symbiont suffered several rearrangements, bringing on a complex interaction between nuclear and organellar gene products. Nowadays, plastids harbor a small genome with ∼130 genes in a 100–220 kb sequence in higher plants. Plastid genes are mostly highly conserved between plant species, being useful for phylogenetic analysis in higher taxa. However, intergenic spacers have a relatively higher mutation rate and are important markers to phylogeographical and plant population genetics analyses. The predominant uniparental inheritance of plastids is like a highly desirable feature for phylogeny studies. Moreover, the gene content and genome rearrangements are efficient tools to capture and understand evolutionary events between different plant species. Currently, genetic engineering of the plastid genome (plastome) offers a number of attractive advantages as high-level of foreign protein expression, marker gene excision, gene expression in operon and transgene containment because of maternal inheritance of plastid genome in most crops. Therefore, plastid genome can be used for adding new characteristics related to synthesis of metabolic compounds, biopharmaceutical, and tolerance to biotic and abiotic stresses. Here, we describe the importance and applications of plastid genome as tools for genetic and evolutionary studies, and plastid transformation focusing on increasing the performance of horticultural species in the field. PMID:26284102

Plastid genomics in horticultural species: importance and applications for plant population genetics, evolution, and biotechnology.

PubMed

Rogalski, Marcelo; do Nascimento Vieira, Leila; Fraga, Hugo P; Guerra, Miguel P

2015-01-01

During the evolution of the eukaryotic cell, plastids, and mitochondria arose from an endosymbiotic process, which determined the presence of three genetic compartments into the incipient plant cell. After that, these three genetic materials from host and symbiont suffered several rearrangements, bringing on a complex interaction between nuclear and organellar gene products. Nowadays, plastids harbor a small genome with ∼130 genes in a 100-220 kb sequence in higher plants. Plastid genes are mostly highly conserved between plant species, being useful for phylogenetic analysis in higher taxa. However, intergenic spacers have a relatively higher mutation rate and are important markers to phylogeographical and plant population genetics analyses. The predominant uniparental inheritance of plastids is like a highly desirable feature for phylogeny studies. Moreover, the gene content and genome rearrangements are efficient tools to capture and understand evolutionary events between different plant species. Currently, genetic engineering of the plastid genome (plastome) offers a number of attractive advantages as high-level of foreign protein expression, marker gene excision, gene expression in operon and transgene containment because of maternal inheritance of plastid genome in most crops. Therefore, plastid genome can be used for adding new characteristics related to synthesis of metabolic compounds, biopharmaceutical, and tolerance to biotic and abiotic stresses. Here, we describe the importance and applications of plastid genome as tools for genetic and evolutionary studies, and plastid transformation focusing on increasing the performance of horticultural species in the field.

Use of SCW4 gene primers in PCR methods for the identification of six medically important Aspergillus species.

PubMed

Arancia, Silvia; Sandini, Silvia; De Carolis, Elena; Vella, Antonietta; Sanguinetti, Maurizio; Norelli, Sandro; De Bernardis, Flavia

2016-10-01

Aspergillus species are the cause of invasive mold infections in immunocompromised patients: Aspergillus fumigatus, A. flavus and A. terreus account for most cases of invasive aspergillosis (IA). As certain species are associated with higher mortality and vary in their resistance to antifungal therapy, diagnosis requires increasingly rapid molecular methods that enable sensitive detection and species discrimination. We have developed PCR and Multiplex PCR assays for the detection of six medically important Aspergillus spp. species DNA in bronchoalveolar lavage (BAL) specimens from hematology and intensive care unit (ICU) patients at risk of IA, using different species and genus-specific PCR primers, selected within the SCW4 gene, encoding a cell wall glucanase of A. fumigatus, similar to mannoprotein Mp65 of Candida albicans. The genus-specific PCR primers were able to amplify only Aspergillus DNAs but not that belonging to other fungal genera tested. The species-specific PCR primers allowed differentiation of each Aspergillus species by the amplicon length produced. The methods described in this study are rapid (less than 4 h), reproducible, simple and specific and demonstrate potential application in the clinical laboratory.

Bud structure, position and fate generate various branching patterns along shoots of closely related Rosaceae species: a review

PubMed Central

Costes, Evelyne; Crespel, Laurent; Denoyes, Béatrice; Morel, Philippe; Demene, Marie-Noëlle; Lauri, Pierre-Eric; Wenden, Bénédicte

2014-01-01

Branching in temperate plants is closely linked to bud fates, either floral or vegetative. Here, we review how the fate of meristematic tissues contained in buds and their position along a shoot imprint specific branching patterns which differ among species. Through examples chosen in closely related species in different genera of the Rosaceae family, a panorama of patterns is apparent. Patterns depend on whether vegetative and floral buds are borne individually or together in mixed buds, develop as the shoot grows or after a rest period, and are located in axillary or terminal positions along the parent shoot. The resulting branching patterns are conserved among varieties in a given species but progressively change with the parent shoot length during plant ontogeny. They can also be modulated by agronomic and environmental conditions. The existence of various organizations in the topology and fate of meristematic tissues and their appendages in closely related species questions the between-species conservation of physiological and molecular mechanisms leading to bud outgrowth vs. quiescence and to floral induction vs. vegetative development. PMID:25520729

Morphology of immature stages of blow fly, Lucilia sinensis Aubertin (Diptera: Calliphoridae), a potential species of forensic importance.

PubMed

Sanit, Sangob; Sukontason, Kom; Kurahashi, Hiromu; Tomberlin, Jeffery K; Wannasan, Anchalee; Kraisittipanit, Rungroj; Sukontason, Kabkaew L

2017-12-01

Lucilia sinensis Aubertin (Diptera: Calliphoridae) is a blow fly species of potential forensic importance since adults are attracted to, and colonize, decomposing vertebrate remains. Blow fly larvae associated with human corpses can be useful evidence in forensic investigations; however, their use is dependent in most cases on proper species identification and availability of developmental data. For identification, morphological information on each life stage is traditionally used. We used scanning electron microscopy (SEM) to examine the ultrastructure of eggs, all instars, and puparia, of L. sinensis. The important characteristics used to differentiate L. sinensis from other species are provided. Distinctive features of the eggs are the slight widening median area extending almost the entire length. The last abdominal segment of the first instar bears elongated outer ventral tubercles along the rim of the last abdominal segment. These tubercles, as well as the well developed median and outer dorsal tubercles, are more prominent in the second and third instars. The surface integument of the tubercles is equipped with circular rows of microtrichia. Pairs of inner dorsal tubercle are absent. Each anterior spiracle is comprised of 9-12 papillae arrange in a single row in the second and third instars. As for the third instar, the dorsal spines between the first and second thoracic segments are delicate, narrow, small, and close together (as row or set). The peristigmatic tufts adjacent to the posterior spiracle of the third instar are moderately branches of short, fine hairs, but minute in puparia. In conclusion, the prominent outer ventral tubercle in all instars and puparia is a new diagnostic feature of L. sinensis and helpful in differentiating it from other Lucilia species that are forensically important. The description of immature L. sinensis in this study will be useful for forensic entomologists in countries where this species exists. Copyright © 2017

Insects associated with hospital environment in Egypt with special reference to the medically important species.

PubMed

Kenawy, Mohamed A; Amer, Hanan S; Lotfy, Nadia M; Khamis, Nagwa; Abdel-Hamid, Yousrya M

2014-12-01

A study was planned to examine the insect fauna associated with two hospitals: urban (A) in Cairo and rural (B) in Banha, Egypt with varying hygienic levels and their adjacent residential areas (AC) and (BC), respectively and to investigate the effect of hygienic level on species composition and relative abundance. A total of 22 species belonging to 7 orders and 15 families were reported in the four study areas of which, Dipterous flies were the most common (8/22, 36.36% species). A total of 5257 adults were collected of which Dipterous flies were the abundant (3800, 72.28% insect) and Musca domestica was the most abundant species (3535, 67.24% insect) which was present in all areas where it was more common / predominant species (21.94%-90.91% insect). Moreover, higher densities of M domestica were in (B) and BC than in (A) or (AC). The heavily infested area was AC (54.55% species) followed by (A), (BC) and (B) however, the total number of the collected insects was higher in (BC) and (B) than in (AC) and (A). This was confirmed by finding maximum diversity indices in (AC) and minimum ones in B. In all areas, means of M domestica was more common during summer/autumn and spring than in the winter. Periplaneta americana collected oily during autumn in AC and was more common in autumn in (BC) while Blatella germanica collected only during summer in (AC) and was more common in autumn in (B). The prevalence and higher abundance of the medically important species mainly M domestica, P. americana and B. germanica in rural hospital than in urban one attribute mainly to the lower hygienic level of rural hospital This require a control program based mainly on sanitation supplemented by other measures to overcome the risk of disease transmission by such insects

Assessment of oil content and fatty acid composition variability in two economically important Hibiscus species.

PubMed

Wang, Ming Li; Morris, Brad; Tonnis, Brandon; Davis, Jerry; Pederson, Gary A

2012-07-04

The Hibiscus genus encompasses more than 300 species, but kenaf (Hibiscus cannabinus L.) and roselle (Hibiscus sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterculic and vernolic acids. The fatty acid composition in the oil can directly affect oil quality and its utilization. However, the variability in oil content and fatty acid composition for these two species is unclear. For these two species, 329 available accessions were acquired from the USDA germplasm collection. Their oil content and fatty acid composition were determined by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Using NMR and GC analyses, we found that Hibiscus seeds on average contained 18% oil and seed oil was composed of six major fatty acids (each >1%) and seven minor fatty acids (each <1%). Hibiscus cannabinus seeds contained significantly higher amounts of oil (18.14%), palmitic (20.75%), oleic (28.91%), vernolic acids (VA, 4.16%), and significantly lower amounts of stearic (3.96%), linoleic (39.49%), and dihydrosterculic acids (DHSA, 1.08%) than H. sabdariffa seeds (17.35%, 18.52%, 25.16%, 3.52%, 4.31%, 44.72%, and 1.57%, respectively). For edible oils, a higher oleic/linoleic (O/L) ratio and lower level of DHSA are preferred, and for industrial oils a high level of VA is preferred. Our results indicate that seeds from H. cannabinus may be of higher quality than H. sabdariffa seeds for these reasons. Significant variability in oil content and major fatty acids was also detected within both species. The variability in oil content and fatty acid composition revealed from this study will be useful for exploring seed utilization and developing new cultivars in these Hibiscus species.

Agronomic and environmental implications of enhanced s-triazine degradation

USGS Publications Warehouse

Krutz, L. J.; Dale L. Shaner,; Mark A. Weaver,; Webb, Richard M.; Zablotowicz, Robert M.; Reddy, Krishna N.; Huang, Y.; Thompson, S. J.

2010-01-01

Novel catabolic pathways enabling rapid detoxification of s-triazine herbicides have been elucidated and detected at a growing number of locations. The genes responsible for s-triazine mineralization, i.e. atzABCDEF and trzNDF, occur in at least four bacterial phyla and are implicated in the development of enhanced degradation in agricultural soils from all continents except Antarctica. Enhanced degradation occurs in at least nine crops and six crop rotation systems that rely on s-triazine herbicides for weed control, and, with the exception of acidic soil conditions and s-triazine application frequency, adaptation of the microbial population is independent of soil physiochemical properties and cultural management practices. From an agronomic perspective, residual weed control could be reduced tenfold in s-triazine-adapted relative to non-adapted soils. From an environmental standpoint, the off-site loss of total s-triazine residues could be overestimated 13-fold in adapted soils if altered persistence estimates and metabolic pathways are not reflected in fate and transport models. Empirical models requiring soil pH and s-triazine use history as input parameters predict atrazine persistence more accurately than historical estimates, thereby allowing practitioners to adjust weed control strategies and model input values when warranted. 

Species-area curves indicate the importance of habitats' contributions to regional biodiversity

USGS Publications Warehouse

Chong, G.W.; Stohlgren, T.J.

2007-01-01

We examined species-area curves, species composition and similarity (Jaccard's coefficients), and species richness in 17 vegetation types to develop a composite index of a vegetation type's contribution to regional species richness. We collected data from 1 to 1000 m2 scales in 147 nested plots in Rocky Mountain National Park, Colorado, USA to compare three species-area curve models' abilities to estimate the number of species observed in each vegetation type. The log(species)-log(area) curve had the largest adjusted coefficients of determination (r2 values) in 12 of the 17 types, followed by the species-log(area) curve with five of the highest values. When the slopes of the curves were corrected for species overlap among plots with Jaccard's coefficients, the species-log(area) curves estimated values closest to those observed. We combined information from species-area curves and measures of heterogeneity with information on the area covered by each vegetation type and found that the types making the greatest contributions to regional biodiversity covered the smallest areas. This approach may provide an accurate and relatively rapid way to rank hotspots of plant diversity within regions of interest.

A preliminary assessment of genetic relationships among agronomically important cultivars of black pepper

PubMed Central

Joy, Nisha; Abraham, Z; Soniya, EV

2007-01-01

Background The impact of diseases such as Phytophthora foot rot and the replacement of unproductive cultivars by high yielding ones has brought about the disappearance of varieties in Piper species, like any other crop. Black pepper (King of spices), is a major spice crop consumed throughout the world. It is widely cultivated across various parts of the world apart from India. The different cultivars may be genetically related and could be a source of valuable genes for disease resistance and an increase in quantity and quality. Even though Western Ghats in India is believed to be the site of origin of this crop, numerous accessions from the NBPGR have not yet been evaluated. Our study aims to investigate the genetic relatedness in major cultivars of black pepper using Amplified Fragment Length Polymorphism. Results Amplified Fragment Length Polymorphic (AFLP) DNA analysis was performed in thirty popular cultivars of black pepper from National Bureau of Plant Genetic Resources (NBPGR), India. Fingerprint profiles were generated initially with, five different primer combinations, from which three primer pair combinations (EAGC/MCAA, EAGG/MCTA and EAGC/MCTG) gave consistent and scorable banding patterns. From 173 scorable markers, 158(> 90%) were polymorphic which shows there is considerable variation in the available germplasm. The dendrogram derived by unweighted pair group method analysis (UPGMA) grouped the accessions into three major clusters and four diverse cultivars with only 30% similarity. Karimunda, a widely grown and popular cultivar was unique in the fingerprint profiles obtained. Conclusion There are currently few fingerprinting studies using the valuable spice crop black pepper. We found considerable genetic variability among cultivars of black pepper. Fingerprinting analysis with AFLP proved to be an ideal tool for cultivar identification and phylogenetic studies. It shows the high level of polymorphism and the unique characterization of the major

The importance of assessing climate change vulnerability to address species conservation

Treesearch

Karen E. Bagne; Megan M. Friggens; Sharon J. Coe; Deborah M. Finch

2014-01-01

Species conservation often prioritizes attention on a small subset of "special status" species at high risk of extinction, but actions based on current lists of special status species may not effectively moderate biodiversity loss if climate change alters threats. Assessments of climate change vulnerability may provide a method to enhance identification of...

Influence of cultivar and fertilizer approach on curly kale (Brassica oleracea L. var. sabellica). 1. Genetic diversity reflected in agronomic characteristics and phytochemical concentration.

PubMed

Groenbaek, Marie; Jensen, Sidsel; Neugart, Susanne; Schreiner, Monika; Kidmose, Ulla; Kristensen, Hanne Lakkenborg

2014-11-26

The objectives were to investigate if genetic diversity among field-grown traditional and F1 hybrid kale cultivars was reflected in different agronomic characteristics and consequently glucosinolate (GLS) and flavonoid glycoside concentration. This study evaluated how nitrogen and sulfur supply and biomass allocation modified phytochemicals in two experiments with combinations of three cultivars and four N and two S application levels. Results showed less growth, and higher N concentration in the traditional cultivar 'Tiara' was associated with increased indole and total GLSs compared to traditional 'Høj Amager Toftø' and F1 hybrid 'Reflex' cultivars, which exhibited higher yield, lower N concentration, and different biomass allocation. S application increased total GLS concentration, whereas aliphatic GLS percentage decreased when N application increased. Decrease of six 'Reflex' GLSs besides quercetin glycosides and total flavonoid glycosides with increased N indicated higher N responsiveness for 'Reflex'. In conclusion, differences in agronomic characteristics were reflected in diverse phytochemical composition.

Chloroplast genes as genetic markers for inferring patterns of change, maternal ancestry and phylogenetic relationships among Eleusine species

PubMed Central

Agrawal, Renuka; Agrawal, Nitin; Tandon, Rajesh; Raina, Soom Nath

2013-01-01

Assessment of phylogenetic relationships is an important component of any successful crop improvement programme, as wild relatives of the crop species often carry agronomically beneficial traits. Since its domestication in East Africa, Eleusine coracana (2n = 4x = 36), a species belonging to the genus Eleusine (x = 8, 9, 10), has held a prominent place in the semi-arid regions of India, Nepal and Africa. The patterns of variation between the cultivated and wild species reported so far and the interpretations based upon them have been considered primarily in terms of nuclear events. We analysed, for the first time, the phylogenetic relationship between finger millet (E. coracana) and its wild relatives by species-specific chloroplast deoxyribonucleic acid (cpDNA) polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and chloroplast simple sequence repeat (cpSSR) markers/sequences. Restriction fragment length polymorphism of the seven amplified chloroplast genes/intergenic spacers (trnK, psbD, psaA, trnH–trnK, trnL–trnF, 16S and trnS–psbC), nucleotide sequencing of the chloroplast trnK gene and chloroplast microsatellite polymorphism were analysed in all nine known species of Eleusine. The RFLP of all seven amplified chloroplast genes/intergenic spacers and trnK gene sequences in the diploid (2n = 16, 18, 20) and allotetraploid (2n = 36, 38) species resulted in well-resolved phylogenetic trees with high bootstrap values. Eleusine coracana, E. africana, E. tristachya, E. indica and E. kigeziensis did not show even a single change in restriction site. Eleusine intermedia and E. floccifolia were also shown to have identical cpDNA fragment patterns. The cpDNA diversity in Eleusine multiflora was found to be more extensive than that of the other eight species. The trnK gene sequence data complemented the results obtained by PCR–RFLP. The maternal lineage of all three allotetraploid species (AABB, AADD) was the same, with E. indica being

Chloroplast genes as genetic markers for inferring patterns of change, maternal ancestry and phylogenetic relationships among Eleusine species.

PubMed

Agrawal, Renuka; Agrawal, Nitin; Tandon, Rajesh; Raina, Soom Nath

2014-01-01

Assessment of phylogenetic relationships is an important component of any successful crop improvement programme, as wild relatives of the crop species often carry agronomically beneficial traits. Since its domestication in East Africa, Eleusine coracana (2n = 4x = 36), a species belonging to the genus Eleusine (x = 8, 9, 10), has held a prominent place in the semi-arid regions of India, Nepal and Africa. The patterns of variation between the cultivated and wild species reported so far and the interpretations based upon them have been considered primarily in terms of nuclear events. We analysed, for the first time, the phylogenetic relationship between finger millet (E. coracana) and its wild relatives by species-specific chloroplast deoxyribonucleic acid (cpDNA) polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and chloroplast simple sequence repeat (cpSSR) markers/sequences. Restriction fragment length polymorphism of the seven amplified chloroplast genes/intergenic spacers (trnK, psbD, psaA, trnH-trnK, trnL-trnF, 16S and trnS-psbC), nucleotide sequencing of the chloroplast trnK gene and chloroplast microsatellite polymorphism were analysed in all nine known species of Eleusine. The RFLP of all seven amplified chloroplast genes/intergenic spacers and trnK gene sequences in the diploid (2n = 16, 18, 20) and allotetraploid (2n = 36, 38) species resulted in well-resolved phylogenetic trees with high bootstrap values. Eleusine coracana, E. africana, E. tristachya, E. indica and E. kigeziensis did not show even a single change in restriction site. Eleusine intermedia and E. floccifolia were also shown to have identical cpDNA fragment patterns. The cpDNA diversity in Eleusine multiflora was found to be more extensive than that of the other eight species. The trnK gene sequence data complemented the results obtained by PCR-RFLP. The maternal lineage of all three allotetraploid species (AABB, AADD) was the same, with E. indica being the

Importance of scale, land cover, and weather on the abundance of bird species in a managed forest

USGS Publications Warehouse

Grinde, Alexis R.; Hiemi, Gerald J.; Sturtevant, Brian R.; Panci, Hannah; Thogmartin, Wayne E.; Wolter, Peter

2017-01-01

Climate change and habitat loss are projected to be the two greatest drivers of biodiversity loss over the coming century. While public lands have the potential to increase regional resilience of bird populations to these threats, long-term data are necessary to document species responses to changes in climate and habitat to better understand population vulnerabilities. We used generalized linear mixed models to determine the importance of stand-level characteristics, multi-scale land cover, and annual weather factors to the abundance of 61 bird species over a 20-year time frame in Chippewa National Forest, Minnesota, USA. Of the 61 species modeled, we were able to build final models with R-squared values that ranged from 26% to 69% for 37 species; the remaining 24 species models had issues with convergence or low explanatory power (R-squared < 20%). Models for the 37 species show that stand-level characteristics, land cover factors, and annual weather effects on species abundance were species-specific and varied within guilds. Forty-one percent of the final species models included stand-level characteristics, 92% included land cover variables at the 200 m scale, 51% included land cover variables at the 500 m scale, 46% included land cover variables at the 1000 m scale, and 38% included weather variables in best models. Three species models (8%) included significant weather and land cover interaction terms. Overall, models indicated that aboveground tree biomass and land cover variables drove changes in the majority of species. Of those species models including weather variables, more included annual variation in precipitation or drought than temperature. Annual weather variability was significantly more likely to impact abundance of species associated with deciduous forests and bird species that are considered climate sensitive. The long-term data and models we developed are particularly suited to informing science-based adaptive forest management plans that

Intra- and inter-species interactions within biofilms of important foodborne bacterial pathogens

PubMed Central

Giaouris, Efstathios; Heir, Even; Desvaux, Mickaël; Hébraud, Michel; Møretrø, Trond; Langsrud, Solveig; Doulgeraki, Agapi; Nychas, George-John; Kačániová, Miroslava; Czaczyk, Katarzyna; Ölmez, Hülya; Simões, Manuel

2015-01-01

A community-based sessile life style is the normal mode of growth and survival for many bacterial species. Under such conditions, cell-to-cell interactions are inevitable and ultimately lead to the establishment of dense, complex and highly structured biofilm populations encapsulated in a self-produced extracellular matrix and capable of coordinated and collective behavior. Remarkably, in food processing environments, a variety of different bacteria may attach to surfaces, survive, grow, and form biofilms. Salmonella enterica, Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus are important bacterial pathogens commonly implicated in outbreaks of foodborne diseases, while all are known to be able to create biofilms on both abiotic and biotic surfaces. Particularly challenging is the attempt to understand the complexity of inter-bacterial interactions that can be encountered in such unwanted consortia, such as competitive and cooperative ones, together with their impact on the final outcome of these communities (e.g., maturation, physiology, antimicrobial resistance, virulence, dispersal). In this review, up-to-date data on both the intra- and inter-species interactions encountered in biofilms of these pathogens are presented. A better understanding of these interactions, both at molecular and biophysical levels, could lead to novel intervention strategies for controlling pathogenic biofilm formation in food processing environments and thus improve food safety. PMID:26347727

Interspecific chromosomal effects on agronomic traits in Gossypium hirsutum by AD analysis using intermated G. barbadense chromosome substitution lines.

PubMed

Saha, S; Wu, J; Jenkins, J N; McCarty, J C; Stelly, D M

2013-01-01

The untapped potential of the beneficial alleles from Gossypium barbadense L. has not been well utilized in G. hirsutum L. (often referred to as Upland cotton) breeding programs. This is primarily due to genomic incompatibility and technical challenges associated with conventional methods of interspecific introgression. In this study, we used a hypoaneuploid-based chromosome substitution line as a means for systematically introgressing G. barbadense doubled-haploid line '3-79' germplasm into a common Upland genetic background, inbred 'Texas marker-1' ('TM-1'). We reported on the chromosomal effects, lint percentage, boll weight, seedcotton yield and lint yield in chromosome substitution CS-B (G. barbadense L.) lines. Using an additive-dominance genetic model, we studied the interaction of alleles located on two alien substituted chromosomes versus one alien substituted chromosome using a partial diallel mating design of selected CS-B lines (CS-B05sh, CS-B06, CS-B09, CS-B10, CS-B12, CS-B17 and CS-B18). Among these parents, CS-B09 and CS-B10 were reported for the first time. The donor parent 3-79, had the lowest additive effect for all of the agronomic traits. All of the CS-B lines had significant additive effects with boll weight and lint percentage. CS-B10 had the highest additive effects for lint percentage, and seedcotton and lint yield among all of the lines showing a transgressive genetic mode of inheritance for these traits. CS-B09 had greater additive genetic effects on lint yield, while CS-B06, CS-B10 and CS-B17 had superior additive genetic effects on both lint and seedcotton yield compared to TM-1 parent. The 3-79 line had the highest dominance effects for boll weight (0.513 g) and CS-B10 had the lowest dominance effect for boll weight (-0.702). Some major antagonistic genetic effects for the agronomic traits were present with most of the substituted chromosomes and chromosome arms, a finding suggested their recalcitrance to conventional breeding efforts

Effects of environmental temperature on oviposition behavior in three blow fly species of forensic importance.

PubMed

Ody, Helen; Bulling, Mark T; Barnes, Kate M

2017-06-01

A number of factors are known to affect blow fly behavior with respect to oviposition. Current research indicates that temperature is the most significant factor. However temperature thresholds for oviposition in forensically important blow flies have not been well studied. Here, the oviposition behavior of three species of forensically important blow fly species (Calliphora vicina, Calliphora vomitoria and Lucilia sericata,) was studied under controlled laboratory conditions over a range of temperatures (10-40°C). Lower temperature thresholds for oviposition of 16°C and 17.5°C were established for C. vomitoria and L. sericata respectively, whilst C. vicina continued to lay eggs at 10°C. C. vomitoria and L. sericata both continued to lay eggs at 40°C, whilst the highest temperature at which oviposition occurred in C. vicina was 35°C. Within these thresholds there was considerable variation in the number of surviving pupae, with a general pattern of a single peak within the range of temperatures at which eggs were laid, but with the pattern being much less distinct for L. sericata. Copyright © 2017 Elsevier B.V. All rights reserved.

Applied Mathematics for agronomical engineers in Spain at UPM

NASA Astrophysics Data System (ADS)

Anton, J. M.; Grau, J. B.; Tarquis, A. M.; Fabregat, J.; Sanchez, M. E.

2009-04-01

Mathematics, created or discovered, are a global human conceptual endowment, containing large systems of knowledge, and varied skills to use definite parts of them, in creation or discovery, or for applications, e.g. in Physics, or notably in engineering behaviour. When getting upper intellectual levels in the 19th century, the agronomical science and praxis was noticeably or mainly organised in Spain in agronomical engineering schools and also in institutes, together with technician schools, also with different lower lever centres, and they have evolved with progress and they are much changing at present to a EEES schema (Bolonia process). They work in different lines that need some basis or skills from mathematics. The vocation to start such careers, that have varied curriculums, contains only some mathematics, and the number of credits for mathematics is restrained because time is necessary for other initial sciences such as applied chemistry, biology, ecology and soil sciences, but some basis and skill of maths are needed, also with Physics, at least for electricity, machines, construction, economics at initial ground levels, and also for Statistics that are here considered part of Applied Mathematics. The ways of teaching mathematical basis and skills are especial, and are different from the practical ways needed e. g. for Soil Sciences, and they involve especial efforts from students, and especial controls or exams that guide much learning. The mathematics have a very large accepted content that uses mostly a standard logic, and that is remarkably stable and international, rather similar notation and expressions being used with different main languages. For engineering the logical basis is really often not taught, but the use of it is transferred, especially for calculus that requires both adapted somehow simplified schemas and the learning of a specific skill to use it, and also for linear algebra. The basic forms of differential calculus in several

A survey of mosquitoes breeding in used tires in Spain for the detection of imported potential vector species.

PubMed

Roiz, D; Eritja, R; Escosa, R; Lucientes, J; Marquès, E; Melero-Alcíbar, R; Ruiz, S; Molina, R

2007-06-01

The used tire trade has facilitated the introduction, spread, and establishment of the Asian tiger mosquito, Aedes albopictus, and other mosquito species in several countries of America, Africa, Oceania, and Europe. A strategy for detecting these imported mosquito vectors was developed in Spain during 2003-2004 by EVITAR (multidisciplinary network for the study of viruses transmitted by arthropods and rodents). A survey in 45 locations found no invasive species. Eight autochthonous species of mosquitoes were detected in used tires, including Culex pipiens, Cx. hortensis, Cx. modestus, Anopheles atroparvus, An. claviger, Culiseta longiareolata, Cs. annulata, and Aedes caspius. Dominant species were Cx. pipiens and Cs. longiareolata. Aedes caspius was found in only once, near its natural breeding habitat. Considering the recent discovery of an established population of Ae. albopictus in Catalonia, the increasing commerce of used tires in Spain for recycling, storage, and recapping might greatly contribute to the rapid spread of this species across the Iberian Peninsula.

Assembly of the draft genome of buckwheat and its applications in identifying agronomically useful genes

PubMed Central

Yasui, Yasuo; Hirakawa, Hideki; Ueno, Mariko; Matsui, Katsuhiro; Katsube-Tanaka, Tomoyuki; Yang, Soo Jung; Aii, Jotaro; Sato, Shingo; Mori, Masashi

2016-01-01

Buckwheat (Fagopyrum esculentum Moench; 2n = 2x = 16) is a nutritionally dense annual crop widely grown in temperate zones. To accelerate molecular breeding programmes of this important crop, we generated a draft assembly of the buckwheat genome using short reads obtained by next-generation sequencing (NGS), and constructed the Buckwheat Genome DataBase. After assembling short reads, we determined 387,594 scaffolds as the draft genome sequence (FES_r1.0). The total length of FES_r1.0 was 1,177,687,305 bp, and the N50 of the scaffolds was 25,109 bp. Gene prediction analysis revealed 286,768 coding sequences (CDSs; FES_r1.0_cds) including those related to transposable elements. The total length of FES_r1.0_cds was 212,917,911 bp, and the N50 was 1,101 bp. Of these, the functions of 35,816 CDSs excluding those for transposable elements were annotated by BLAST analysis. To demonstrate the utility of the database, we conducted several test analyses using BLAST and keyword searches. Furthermore, we used the draft genome as a reference sequence for NGS-based markers, and successfully identified novel candidate genes controlling heteromorphic self-incompatibility of buckwheat. The database and draft genome sequence provide a valuable resource that can be used in efforts to develop buckwheat cultivars with superior agronomic traits. PMID:27037832

Genetic divergence among corn hybrids and combining ability for agronomic and bromatological traits of silage.

PubMed

Gralak, E; Faria, M V; Figueiredo, A S T; Rizzardi, D A; Neumann, M; Mendes, M C; Scapim, C A; Galbeiro, S

2017-05-25

We assessed the impact of genetic divergence and the ability to combine corn hybrids used for the production of silage on the agronomic and bromatological traits of silage quality. We evaluated 18 corn hybrids used as genitors in a circulant diallel scheme in which each genitor hybrid participated in 9 hybrid combinations, and evaluated 100 treatments [18 genitor hybrids, 81 diallelic hybrids, and a commercial check hybrid (DKB330)] in a triple lattice 10 x 10 experimental design in two environments in Brazil. Genetic variability was adequate among the corn silage hybrids, and we can recommend the use of genitors 2B688 and P30B39 for the formation of a base population for intrapopulational breeding. The P30P34 hybrid is the best for intrapopulational breeding when aiming for silage with high protein content, low fiber content, and higher in vitro digestibility. Interpopulational breeding directed at improving silage digestibility can use a combination of genitors P30P34 and AS1572, but AS1572 and P30K64 are the most recommended. Hybrids 2B688, P30P34, and SG6015 are considered the most genetically distant of the others hybrids, and have desirable combining potential; therefore, they are important genitors for the formation of new segregated populations for improving corn silage.

Narrowing the agronomic yield gap with improved nitrogen use efficiency: a modeling approach.

PubMed

Ahrens, T D; Lobell, D B; Ortiz-Monasterio, J I; Li, Y; Matson, P A

2010-01-01

Improving nitrogen use efficiency (NUE) in the major cereals is critical for more sustainable nitrogen use in high-input agriculture, but our understanding of the potential for NUE improvement is limited by a paucity of reliable on-farm measurements. Limited on-farm data suggest that agronomic NUE (AE(N)) is lower and more variable than data from trials conducted at research stations, on which much of our understanding of AE(N) has been built. The purpose of this study was to determine the magnitude and causes of variability in AE(N) across an agricultural region, which we refer to as the achievement distribution of AE(N). The distribution of simulated AE(N) in 80 farmers' fields in an irrigated wheat system in the Yaqui Valley, Mexico, was compared with trials at a local research center (International Wheat and Maize Improvement Center; CIMMYT). An agroecosystem simulation model WNMM was used to understand factors controlling yield, AE(N), gaseous N emissions, and nitrate leaching in the region. Simulated AE(N) in the Yaqui Valley was highly variable, and mean on-farm AE(N) was 44% lower than trials with similar fertilization rates at CIMMYT. Variability in residual N supply was the most important factor determining simulated AE(N). Better split applications of N fertilizer led to almost a doubling of AE(N), increased profit, and reduced N pollution, and even larger improvements were possible with technologies that allow for direct measurement of soil N supply and plant N demand, such as site-specific nitrogen management.

Stability of agronomic and yield related traits of Jatropha curcas accessions raised from cuttings

NASA Astrophysics Data System (ADS)

Mat, Nurul Hidayah Che; Yaakob, Zahira; Ratnam, Wickneswari

2016-11-01

Monitoring stability of agronomic and yield related traits is important for prediction of crop yields. This study was a latter study for the evaluation of 295 J. curcas individuals representing 21 accessions from eight countries at Biodiesel Research Station of Universiti Kebangsaan Malaysia, Kuala Pilah planted in December 2012. In this study, 183 J. curcas individuals were selected randomly from the population and their growth performance evaluated from December 2013 to December 2014. All the individual plants were raised from cuttings. The yield related data were recorded periodically and performance of each accession was analyzed using Statistical Analysis System (SAS) 9.4. Five traits which were number of fruits per plant (NFPP), number of fruits per inflorescence (NFPI), hundred seed weight (g) (HSW), number of seeds per plant (NSPP) and yield per plant (g) (YPP) showed significant differences among the accessions after two years of planting. Maximum values for each trait were 208 cm for plant height (PH), 31 for number of branches per plant (BPP), 115 for number of inflorescence per plant (NIPP), 582 for NFPP, 7 for NFPI, 307 for number of flowers per inflorescence (NFI), 17 for number of female flowers per inflorescence (NFFPI), 91.6 g for HSW, 1647.1 for NSPP and 927.6 g for YPP. Most of the plants which had performed well in the first year were among the best performers in the second year.

Relationships of the Woody Medicago Species (Section Dendrotelis) Assessed by Molecular Cytogenetic Analyses

PubMed Central

Rosato, Marcela; Castro, Mercedes; Rosselló, Josep A.

2008-01-01

Background and Aims The organization of rDNA genes in the woody medic species from the agronomically important Medicago section Dendrotelis was analysed to gain insight into their taxonomic relationships, to assess the levels of infraspecific variation concerning ribosomal loci in a restricted and fragmented insular species (M. citrina) and to assess the nature of its polyploidy. Methods Fluorescence in situ hybridization (FISH) was used for physical mapping of 5S and 45S ribosomal DNA genes in the three species of section Dendrotelis (M. arborea, M. citrina, M. strasseri) and the related M. marina from section Medicago. Genomic in situ hybridization (GISH) was used to assess the genomic relationships of the polyploid M. citrina with the putatively related species from section Dendrotelis. Key Results The diploid (2n = 16) M. marina has a single 45S and two 5S rDNA loci, a pattern usually detected in previous studies of Medicago diploid species. However, polyploid species from section Dendrotelis depart from expectations. The tetraploid species (2n = 32) M. arborea and M. strasseri have one 45S rDNA locus and two 5S rDNA loci, whereas in the hexaploid (2n = 48) M. citrina four 45S rDNA and five 5S rDNA loci have been detected. No single chromosome of M. citrina was uniformly labelled after using genomic probes from M. arborea and M. strasseri. Instead, cross-hybridization signals in M. citrina were restricted to terminal chromosome arms and NOR regions. Conclusions FISH results support the close taxonomic interrelationship between M. arborea and M. strasseri. In these tetraploid species, NOR loci have experienced a diploidization event through physical loss of sequences, a cytogenetic feature so far not reported in other species of the genus. The high number of rDNA loci and GISH results support the specific status for the hexaploid M. citrina, and it is suggested that this species is not an autopolyploid derivative of M. arborea or M. strasseri. Further, molecular

Sewage sludge hydrochars: properties and agronomic impact as related to different production conditions

NASA Astrophysics Data System (ADS)

Paneque, Marina; María De la Rosa, José; Aragón, Carlos; Kern, Jürgen; Conte, Pellegrino; Knicker, Heike

2015-04-01

The huge amount of sewage sludge (SS) generated in wastewater treatment plants all over the world represents an environmental problem. Due to the high concentration of phosphorus and nitrogen in SS as well as other macro and micro nutrients it has been considered a suitable soil amendment. However, before being applied to soil a complete sterilization and elimination of pollutants should be carried out [1]. In this context, thermal treatments appear as a convenient methodology for producing SS byproducts useful for agronomic purposes. Hydrothermal carbonization (HTC) is a kind of pyrolysis characterized by the heating of the biomass in presence of water. This process shows an advantage compared to other thermal treatments for wet residues since dryness of the biomass prior to the thermal transformation is not necessary. The solid product which results from HTC is called hydrochar and it has been suggested to increase soil productivity [2]. However, the agronomic potential of hydrochars depends on the feedstock and production conditions. Additionally, possible toxic and risks have to be carefully evaluated. Thus, SS hydrochars appear as a potential soil amendment but further scientific research is needed to find its real capacity, optimal production conditions as well as possible environmental harmful effects. The aim of this study was to evaluate which are the most suitable production conditions, to transform SS into hydrochar. An additional goal of this work was to relate the hydrochars properties to its agronomic response. Therefore, hydrochars were produced from SS collected from the Experimental Wastewater Treatment plant of CENTA (http://www.centa.es/), located in Carrion de los Cespedes (Seville), under two different temperatures (200 and 260˚C) and residence times (30 min and 1h). With the hydrochars obtained, a greenhouse pot incubation study was carried out for 80 days. The pots contained 250 g of a Calcic Cambisol (IUSS Working Group WRB, 2007) and an

Genetic variation and relationships of four species of medically important echinostomes (Trematoda: Echinostomatidae) in South-East Asia.

PubMed

Saijuntha, Weerachai; Sithithaworn, Paiboon; Duenngai, Kunyarat; Kiatsopit, Nadda; Andrews, Ross H; Petney, Trevor N

2011-03-01

Multilocus enzyme electrophoresis (MEE) and DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene were used to genetically compare four species of echinostomes of human health importance. Fixed genetic differences among adults of Echinostoma revolutum, Echinostoma malayanum, Echinoparyphium recurvatum and Hypoderaeum conoideum were detected at 51-75% of the enzyme loci examined, while interspecific differences in CO1 sequence were detected at 16-32 (8-16%) of the 205 alignment positions. The results of the MEE analyses also revealed fixed genetic differences between E. revolutum from Thailand and Lao PDR at five (19%) of 27 loci, which could either represent genetic variation between geographically separated populations of a single species, or the existence of a cryptic (i.e. genetically distinct but morphologically similar) species. However, there was no support for the existence of cryptic species within E. revolutum based on the CO1 sequence between the two geographical areas sampled. Genetic variation in CO1 sequence was also detected among E. malayanum from three different species of snail intermediate host. Separate phylogenetic analyses of the MEE and DNA sequence data revealed that the two species of Echinostoma (E. revolutum and E. malayanum) did not form a monophyletic clade. These results, together with the large number of morphologically similar species with inadequate descriptions, poor specific diagnoses and extensive synonymy, suggest that the morphological characters used for species taxonomy of echinostomes in South-East Asia should be reconsidered according to the concordance of biology, morphology and molecular classification. Copyright © 2010 Elsevier B.V. All rights reserved.

Validation of mega-environment universal and specific QTL associated with seed yield and agronomic traits in soybeans.

PubMed

Palomeque, Laura; Liu, Li-Jun; Li, Wenbin; Hedges, Bradley R; Cober, Elroy R; Smid, Mathew P; Lukens, Lewis; Rajcan, Istvan

2010-03-01

The value of quantitative trait loci (QTL) is dependent on the strength of association with the traits of interest, allelic diversity at the QTL and the effect of the genetic background on the expression of the QTL. A number of recent studies have identified QTL associated with traits of interest that appear to be independent of the environment but dependent on the genetic background in which they are found. Therefore, the objective of this study was to validate universal and/or mega-environment-specific seed yield QTL that have been previously reported in an independent recombinant inbred line (RIL) population derived from the cross between an elite Chinese and Canadian parent. The population was evaluated at two field environments in China and in five environments in Canada in 2005 and 2006. Of the seven markers linked to seed yield QTL reported by our group in a previous study, four were polymorphic between the two parents. No association between seed yield and QTL was observed. The result could imply that seed yield QTL were either not stable in this particular genetic background or harboured different alleles than the ones in the original mapping population. QTL(U) Satt162 was associated with several agronomic traits of which lodging was validated. Both the non-adapted and adapted parent contributed favourable alleles to the progeny. Therefore, plant introductions have been validated as a source of favourable alleles that could increase the genetic variability of the soybean germplasm pool and lead to further improvements in seed yield and other agronomic traits.

Interspecific shared collective decision-making in two forensically important species.

PubMed

Boulay, Julien; Deneubourg, Jean-Louis; Hédouin, Valéry; Charabidzé, Damien

2016-02-10

To date, the study of collective behaviour has mainly focused on intraspecific situations: the collective decision-making of mixed-species groups involving interspecific aggregation-segregation has received little attention. Here, we show that, in both conspecific and heterospecific groups, the larvae of two species (Lucilia sericata and Calliphora vomitoria, calliphorid carrion-feeding flies) were able to make a collective choice. In all groups, the choice was made within a few minutes and persisted throughout the period of the experiment. The monitoring of a focal individual within a group showed that these aggregations were governed by attractive and retentive effects of the group. Furthermore, the similarity observed between the conspecific and heterospecific groups suggested the existence of shared aggregation signals. The group size was found to have a stronger influence than the species of necrophagous larvae. These results should be viewed in relation to the well-known correlation between group size and heat generation. This study provides the first experimental examination of the dynamics of collective decision-making in mixed-species groups of invertebrates, contributing to our understanding of the cooperation-competition phenomenon in animal social groups. © 2016 The Author(s).

The importance of sphingolipids and reactive oxygen species in cardiovascular development.

PubMed

de Faria Poloni, Joice; Chapola, Henrique; Feltes, Bruno César; Bonatto, Diego

2014-06-01

The heart is the first organ in the embryo to form. Its structural and functional complexity is the result of a thorough developmental program, where sphingolipids play an important role in cardiogenesis, heart maturation, angiogenesis, the regulation of vascular tone and vessel permeability. Sphingolipids are necessary for signal transduction and membrane microdomain formation. In addition, recent evidence suggests that sphingolipid metabolism is directly interconnected to the modulation of oxidative stress. However, cardiovascular development is highly sensitive to excessive reactive species production, and disturbances in sphingolipid metabolism can lead to abnormal development and cardiac disease. Therefore, in this review, we address the molecular link between sphingolipids and oxidative stress, connecting these pathways to cardiovascular development and cardiovascular disease. © 2014 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.

Genetic divergence of the common bean (Phaseolus vulgaris L.) group Carioca using morpho-agronomic traits by multivariate analysis.

PubMed

Gonçalves Ceolin, Ana Cristina; Gonçalves-Vidigal, Maria Celeste; Soares Vidigal Filho, Pedro; Vinícius Kvitschal, Marcus; Gonela, Adriana; Alberto Scapim, Carlos

2007-03-01

The objective of this study was to evaluate the genetic divergence among the common bean group Carioca by the Tocher method (based on Mahalanobis distance) and graphic dispersion of canonic variables, aiming to identify populations with wide genetic variability. Eighteen genotypes were evaluated in four seasons using a randomized block design with four replications. The mean weight of 100 seeds, in three experiments, and the mean number of pods per plant, in one experiment, were the most important characteristics for the genetic divergence, representing more than 46% of the total variation in the first canonic variable. The first two canonic variables were sufficient to explain about 88.23% of the total variation observed in the average of the four environments. The results showed that CNFC 8008 and CNFC 8009 genotypes presented the best yield averages in all the experiments. While Pérola, Princesa and CNFC 8005 cultivars were the most dissimilar for morpho-agronomic traits. Therefore, the combinations of PérolaxCNFC 8008, CNFC 8005xCNFC 8009, PérolaxCNFC 8009, PrincesaxCNFC 8008 and PrincesaxCNFC 8009 were indicated for interpopulational breeding.

Plastic mulching in agriculture. Trading short-term agronomic benefits for long-term soil degradation?

PubMed

Steinmetz, Zacharias; Wollmann, Claudia; Schaefer, Miriam; Buchmann, Christian; David, Jan; Tröger, Josephine; Muñoz, Katherine; Frör, Oliver; Schaumann, Gabriele Ellen

2016-04-15

Plastic mulching has become a globally applied agricultural practice for its instant economic benefits such as higher yields, earlier harvests, improved fruit quality and increased water-use efficiency. However, knowledge of the sustainability of plastic mulching remains vague in terms of both an environmental and agronomic perspective. This review critically discusses the current understanding of the environmental impact of plastic mulch use by linking knowledge of agricultural benefits and research on the life cycle of plastic mulches with direct and indirect implications for long-term soil quality and ecosystem services. Adverse effects may arise from plastic additives, enhanced pesticide runoff and plastic residues likely to fragment into microplastics but remaining chemically intact and accumulating in soil where they can successively sorb agrochemicals. The quantification of microplastics in soil remains challenging due to the lack of appropriate analytical techniques. The cost and effort of recovering and recycling used mulching films may offset the aforementioned benefits in the long term. However, comparative and long-term agronomic assessments have not yet been conducted. Furthermore, plastic mulches have the potential to alter soil quality by shifting the edaphic biocoenosis (e.g. towards mycotoxigenic fungi), accelerate C/N metabolism eventually depleting soil organic matter stocks, increase soil water repellency and favour the release of greenhouse gases. A substantial process understanding of the interactions between the soil microclimate, water supply and biological activity under plastic mulches is still lacking but required to estimate potential risks for long-term soil quality. Currently, farmers mostly base their decision to apply plastic mulches rather on expected short-term benefits than on the consideration of long-term consequences. Future interdisciplinary research should therefore gain a deeper understanding of the incentives for farmers

Ecological and agronomic importance of the plant genus Lotus. Its application in grassland sustainability and the amelioration of constrained and contaminated soils.

PubMed

Escaray, Francisco J; Menendez, Ana B; Gárriz, Andrés; Pieckenstain, Fernando L; Estrella, María J; Castagno, Luis N; Carrasco, Pedro; Sanjuán, Juan; Ruiz, Oscar A

2012-01-01

The genus Lotus comprises around 100 annual and perennial species with worldwide distribution. The relevance of Lotus japonicus as a model plant has been recently demonstrated in numerous studies. In addition, some of the Lotus species show a great potential for adaptation to a number of abiotic stresses. Therefore, they are relevant components of grassland ecosystems in environmentally constrained areas of several South American countries and Australia, where they are used for livestock production. Also, the fact that the roots of these species form rhizobial and mycorrhizal associations makes the annual L. japonicus a suitable model plant for legumes, particularly in studies directed to recognize the mechanisms intervening in the tolerance to abiotic factors in the field, where these interactions occur. These properties justify the increased utilization of some Lotus species as a strategy for dunes revegetation and reclamation of heavy metal-contaminated or burned soils in Europe. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Phylogeny of economically important insect pests that infesting several crops species in Malaysia

NASA Astrophysics Data System (ADS)

Ghazali, Siti Zafirah; Zain, Badrul Munir Md.; Yaakop, Salmah

2014-09-01

This paper reported molecular data on insect pests of commercial crops in Peninsular Malaysia. Fifteen insect pests (Metisa plana, Calliteara horsefeldii, Cotesia vestalis, Bactrocera papayae, Bactrocera carambolae, Bactrocera latifrons, Conopomorpha cramella, Sesamia inferens, Chilo polychrysa, Rhynchophorus vulneratus, and Rhynchophorus ferrugineus) of nine crops were sampled (oil palm, coconut, paddy, cocoa, starfruit, angled loofah, guava, chili and mustard) and also four species that belong to the fern's pest (Herpetogramma platycapna) and storage and rice pests (Tribolium castaneum, Oryzaephilus surinamensis and Cadra cautella). The presented phylogeny summarized the initial phylogenetic hypothesis, which concerning by implementation of the economically important insect pests. In this paper, phylogenetic relationships among 39 individuals of 15 species that belonging to three orders under 12 genera were inferred from DNA sequences of mitochondrial marker, cytochrome oxidase subunit I (COI) and nuclear marker, ribosomal DNA 28S D2 region. The phylogenies resulted from the phylogenetic analyses of both genes are relatively similar, but differ in the sequence of evolution. Interestingly, this most recent molecular data of COI sequences data by using Bayesian Inference analysis resulted a more-resolved phylogeny that corroborated with traditional hypotheses of holometabolan relationships based on traditional hypotheses of holometabolan relationships and most of recently molecular study compared to 28S sequences. This finding provides the information on relationships of pests species, which infested several crops in Malaysia and also estimation on Holometabola's order relationships. The identification of the larval stages of insect pests could be done accurately, without waiting the emergence of adults and supported by the phylogenetic tree.

Outcrossing potential between 11 important genetically modified crops and the Chilean vascular flora.

PubMed

Sánchez, Miguel A; Cid, Pablo; Navarrete, Humberto; Aguirre, Carlos; Chacón, Gustavo; Salazar, Erika; Prieto, Humberto

2016-02-01

The potential impact of genetically modified (GM) crops on biodiversity is one of the main concerns in an environmental risk assessment (ERA). The likelihood of outcrossing and pollen-mediated gene flow from GM crops and non-GM crops are explained by the same principles and depend primarily on the biology of the species. We conducted a national-scale study of the likelihood of outcrossing between 11 GM crops and vascular plants in Chile by use of a systematized database that included cultivated, introduced and native plant species in Chile. The database included geographical distributions and key biological and agronomical characteristics for 3505 introduced, 4993 native and 257 cultivated (of which 11 were native and 246 were introduced) plant species. Out of the considered GM crops (cotton, soya bean, maize, grape, wheat, rice, sugar beet, alfalfa, canola, tomato and potato), only potato and tomato presented native relatives (66 species total). Introduced relative species showed that three GM groups were formed having: a) up to one introduced relative (cotton and soya bean), b) up to two (rice, grape, maize and wheat) and c) from two to seven (sugar beet, alfalfa, canola, tomato and potato). In particular, GM crops presenting introduced noncultivated relative species were canola (1 relative species), alfalfa (up to 4), rice (1), tomato (up to 2) and potato (up to 2). The outcrossing potential between species [OP; scaled from 'very low' (1) to 'very high' (5)] was developed, showing medium OPs (3) for GM-native relative interactions when they occurred, low (2) for GMs and introduced noncultivated and high (4) for the grape-Vitis vinifera GM-introduced cultivated interaction. This analytical tool might be useful for future ERA for unconfined GM crop release in Chile. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Important sources and chemical species of ambient fine particles related to adverse health effects

NASA Astrophysics Data System (ADS)

Heo, J.

2017-12-01

Although many epidemiological studies have reported that exposure to ambient fine particulate matter (PM2.5) has been linked to increases in mortality and mobidity health outcomes, the key question of which chemical species and sources of PM2.5 are most harmful to public health remains unanswered in the air pollution research area. This study was designed to address the key question with evaluating the risks of exposure to chemical species and source-specific PM2.5 mass on morbidity. Hourly measurements of PM2.5 mass and its major chemical species, including organic carbon, elemental carbon, ions, and trace elements, were observed from January 1 to December 31, 2013 at four of the PM2.5 supersites in urban environments in Korea and the reuslts were used in a positive matrix factorization to estimate source contributions to PM2.5 mass. Nine sources, including secondary sulfate, secondary nitrate, mobile, biomass burning, roadway emission, industry, oil combustion, soil, and aged sea salt, were identified and secondary inorganic aerosol factors (i.e. secondary sulfalte, and secondary nitrate) were the dominant sources contributing to 40% of the total PM2.5 mass in the study region. In order to evaluate the risks of exposure to chemical species and sources of PM2.5 on morbidity, emergency room visits for cardivascular disease and respiratory disease were considered. Hourly health outcomes were compared with hourly measurments of the PM2.5 chemical species and sources using a poission generalized linear model incorporating natural splines, as well as time-stratified case-crossover design. The PM2.5 mass and speveral chemical components, such as organic carbon, elemetal carbon, zinc, and potassium, were strongly associated with morbidity. Source-apporitionmened PM2.5 mass derived from biomass burning, and mobile sources, was significantly associated with cardiovascular and respiratory diseases. The findings represent that local combustion may be particularly important

Recent advancements to study flowering time in almond and other Prunus species

PubMed Central

Sánchez-Pérez, Raquel; Del Cueto, Jorge; Dicenta, Federico; Martínez-Gómez, Pedro

2014-01-01

Flowering time is an important agronomic trait in almond since it is decisive to avoid the late frosts that affect production in early flowering cultivars. Evaluation of this complex trait is a long process because of the prolonged juvenile period of trees and the influence of environmental conditions affecting gene expression year by year. Consequently, flowering time has to be studied for several years to have statistical significant results. This trait is the result of the interaction between chilling and heat requirements. Flowering time is a polygenic trait with high heritability, although a major gene Late blooming (Lb) was described in “Tardy Nonpareil.” Molecular studies at DNA level confirmed this polygenic nature identifying several genome regions (Quantitative Trait Loci, QTL) involved. Studies about regulation of gene expression are scarcer although several transcription factors have been described as responsible for flowering time. From the metabolomic point of view, the integrated analysis of the mechanisms of accumulation of cyanogenic glucosides and flowering regulation through transcription factors open new possibilities in the analysis of this complex trait in almond and in other Prunus species (apricot, cherry, peach, plum). New opportunities are arising from the integration of recent advancements including phenotypic, genetic, genomic, transcriptomic, and metabolomics studies from the beginning of dormancy until flowering. PMID:25071812

Genome Editing with Engineered Nucleases in Economically Important Animals and Plants: State of the Art in the Research Pipeline.

PubMed

Sovová, Tereza; Kerins, Gerard; Demnerová, Kateřina; Ovesná, Jaroslava

2017-01-01

After induced mutagenesis and transgenesis, genome editing is the next step in the development of breeding techniques. Genome editing using site-directed nucleases - including meganucleases, zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the CRISPR/Cas9 system - is based on the mechanism of double strand breaks. The nuclease is directed to cleave the DNA at a specific place of the genome which is then repaired by natural repair mechanisms. Changes are introduced during the repair that are either accidental or can be targeted if a DNA template with the desirable sequence is provided. These techniques allow making virtually any change to the genome including specific DNA sequence changes, gene insertion, replacements or deletions with unprecedented precision and specificity while being less laborious and more straightforward compared to traditional breeding techniques or transgenesis. Therefore, the research in this field is developing quickly and, apart from model species, multiple studies have focused on economically important species and agronomically important traits that were the key subjects of this review. In plants, studies have been undertaken on disease resistance, herbicide tolerance, nutrient metabolism and nutritional value. In animals, the studies have mainly focused on disease resistance, meat production and allergenicity of milk. However, none of the promising studies has led to commercialization despite several patent applications. The uncertain legal status of genome-editing methods is one of the reasons for poor commercial development, as it is not clear whether the products would fall under the GMO regulation. We believe this issue should be clarified soon in order to allow promising methods to reach their full potential.

Atlas of Relations Between Climatic Parameters and Distributions of Important Trees and Shrubs in North America - Alaska Species and Ecoregions

USGS Publications Warehouse

Thompson, Robert S.; Anderson, Katherine H.; Strickland, Laura E.; Shafer, Sarah L.; Pelltier, Richard T.; Bartlein, Patrick J.

2006-01-01

Climate is the primary factor in controlling the continental-scale distribution of plant species, although the relations between climatic parameters and species' ranges is only now beginning to be quantified. Preceding volumes of this atlas explored the continental-scale relations between climatic parameters and the distributions of woody plant species across all of the continent of North America. This volume presents similar information for important woody species, groups of species, and ecoregions in more detail for the State of Alaska. For these analyses, we constructed a 25-kilometer equal-area grid of modern climatic and bioclimatic parameters for North America from instrumental weather records. We obtained a digital representation of the geographic distribution of each species or ecoregion, either from a published source or by digitizing the published distributions ourselves. The presence or absence of each species or ecoregion was then determined for each point on the 25-kilometer grid, thus providing a basis for comparison of the climatic data with the geographic distribution of each species or ecoregion. The relations between climate and these distributions are presented in graphical and tabular form.

Magnitude differences in agronomic, chemical, nutritional, and structural features among different varieties of forage corn grown on dry land and irrigated land.

PubMed

Xin, Hangshu; Abeysekara, Samen; Zhang, Xuewei; Yu, Peiqiang

2015-03-11

In this study, eight varieties of corn forage grown in semiarid western Canada (including Pioneer P2501, Pioneer P39m26, Pioneer P7443, Hyland HL3085, Hyland HLBaxxos, Hyland HLR219, Hyland HLSR22, and Pickseed Silex BT) were selected to explore the effect of irrigation implementation in comparison with nonirrigation on (1) agronomic characteristics, (2) basic chemical profiles explored by using a near-infrared reflectance (NIR) system, and (3) protein and carbohydrate internal structural parameters revealed by using an attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) system. Also, principal component analysis (PCA) was performed on spectroscopic data for clarification of differences in molecular structural makeup among the varieties. The results showed that irrigation treatment significantly increased (P < 0.05) contents of dry matter (DM) and organic matter (OM) but decreased crude protein (CP) of corn forages. Significant interactions of irrigation treatment and corn variety were observed on most agronomic characteristics (DM yield, T/ha, days to tasseling, days to silking) and crude fiber (CF) and ether extract (EE) contents as well as some spectral data such as cellulosic compounds (CELC) peak intensity, peak ratios of CHO third peak to CELC, α-helix to β-sheet, and CHO third peak to amide I. Additionally, the spectral ratios of chemical functional groups that related to structural and nonstructural carbohydrates and protein polymers in forages did not remain constant over corn varieties cultivated with and without water treatment. Moreover, different cultivars had different growth, structure, and nutrition performances in this study. Although significant differences could be found in peak intensities, PCA results indicated some structural similarities existed between two treated corn forages with the exception of HL3085 and HLBaxxos. In conclusion, irrigation and corn variety had interaction effects on agronomic, chemical

A comparison of gravid and under-house CO2-baited CDC light traps for mosquito species of public health importance in Houston, Texas.

PubMed

White, Stephanie L; Ward, Michael P; Budke, Christine M; Cyr, Tracy; Bueno, Rudy

2009-11-01

The relative efficacy of gravid and under-house CO2 traps for monitoring mosquito species of public health importance within the Houston metroplex area was assessed. Gravid and under-house traps were colocated at 10 sites and monitored weekly between 1 March to 31 May 2007. The most numerous species caught was Culex pipiens quinquefasciatus Say. Other species of public health importance caught in gravid and under-house traps included Culex restuans Theobald, Aedes aegypti (L.), and Aedes albopictus Skuse. Adjusting for the week of collection, gravid traps caught significantly more mosquitoes (mean 23.1 per trap) in the study area than under-house traps (mean 3.6 per trap). However, under-house traps caught a greater variety of mosquito species (13) than gravid traps (11). Gravid and under-house traps only caught nine of 15 of the same mosquito species during the study period. In this study area, gravid traps should be used as the primary method of surveillance for mosquito-borne diseases of public health importance during the early part of the season, because of greater catch numbers of mosquitoes that pose a public health risk.

The Change of a Medically Important Genus: Worldwide Occurrence of Genetically Diverse Novel Brucella Species in Exotic Frogs.

PubMed

Scholz, Holger C; Mühldorfer, Kristin; Shilton, Cathy; Benedict, Suresh; Whatmore, Adrian M; Blom, Jochen; Eisenberg, Tobias

2016-01-01

The genus Brucella comprises various species of both veterinary and human medical importance. All species are genetically highly related to each other, sharing intra-species average nucleotide identities (ANI) of > 99%. Infections occur among various warm-blooded animal species, marine mammals, and humans. Until recently, amphibians had not been recognized as a host for Brucella. In this study, however, we show that novel Brucella species are distributed among exotic frogs worldwide. Comparative recA gene analysis of 36 frog isolates from various continents and different frog species revealed an unexpected high genetic diversity, not observed among classical Brucella species. In phylogenetic reconstructions the isolates consequently formed various clusters and grouped together with atypical more distantly related brucellae, like B. inopinata, strain BO2, and Australian isolates from rodents, some of which were isolated as human pathogens. Of one frog isolate (10RB9215) the genome sequence was determined. Comparative genome analysis of this isolate and the classical Brucella species revealed additional genetic material, absent from classical Brucella species but present in Ochrobactrum, the closest genetic neighbor of Brucella, and in other soil associated genera of the Alphaproteobacteria. The presence of gene clusters encoding for additional metabolic functions, flanked by tRNAs and mobile genetic elements, as well as by bacteriophages is suggestive for a different ecology compared to classical Brucella species. Furthermore it suggests that amphibian isolates may represent a link between free living soil saprophytes and the pathogenic Brucella with a preferred intracellular habitat. We therefore assume that brucellae from frogs have a reservoir in soil and, in contrast to classical brucellae, undergo extensive horizontal gene transfer.

Assembly of the draft genome of buckwheat and its applications in identifying agronomically useful genes.

PubMed

Yasui, Yasuo; Hirakawa, Hideki; Ueno, Mariko; Matsui, Katsuhiro; Katsube-Tanaka, Tomoyuki; Yang, Soo Jung; Aii, Jotaro; Sato, Shingo; Mori, Masashi

2016-06-01

Buckwheat (Fagopyrum esculentum Moench; 2n = 2x = 16) is a nutritionally dense annual crop widely grown in temperate zones. To accelerate molecular breeding programmes of this important crop, we generated a draft assembly of the buckwheat genome using short reads obtained by next-generation sequencing (NGS), and constructed the Buckwheat Genome DataBase. After assembling short reads, we determined 387,594 scaffolds as the draft genome sequence (FES_r1.0). The total length of FES_r1.0 was 1,177,687,305 bp, and the N50 of the scaffolds was 25,109 bp. Gene prediction analysis revealed 286,768 coding sequences (CDSs; FES_r1.0_cds) including those related to transposable elements. The total length of FES_r1.0_cds was 212,917,911 bp, and the N50 was 1,101 bp. Of these, the functions of 35,816 CDSs excluding those for transposable elements were annotated by BLAST analysis. To demonstrate the utility of the database, we conducted several test analyses using BLAST and keyword searches. Furthermore, we used the draft genome as a reference sequence for NGS-based markers, and successfully identified novel candidate genes controlling heteromorphic self-incompatibility of buckwheat. The database and draft genome sequence provide a valuable resource that can be used in efforts to develop buckwheat cultivars with superior agronomic traits. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Detection of four important Eimeria species by multiplex PCR in a single assay.

PubMed

You, Myung-Jo

2014-06-01

The oocysts of some of the recognized species of chicken coccidiosis are difficult to distinguish morphologically. Diagnostic laboratories are increasingly utilizing DNA-based technologies for the specific identification of Eimeria species. This study reports a multiplex polymerase chain reaction (PCR) assay based on internal transcribed spacer-1 (ITS-1) for the simultaneous diagnosis of the Eimeria tenella, Eimeria acervulina, Eimeria maxima, and Eimeria necatrix species, which infect domestic fowl. Primer pairs specific to each species were designed in order to generate a ladder of amplification products ranging from 20 to 25 bp, and a common optimum annealing temperature for these species was determined to be 52.5 °C. Sensitivity tests were performed for each species, showing a detection threshold of 1-5 pg. All the species were amplified homogeneously, and a homogenous band ladder was observed, indicating that the assay permitted the simultaneous detection of all the species in a single-tube reaction. In the phylogenic study, there was a clear species clustering, which was irrespective of geographical location, for all the ITS-1 sequences used. This multiplex PCR assay represents a rapid and potential cost-effective diagnostic method for the detection of some key Eimeria species that infect domestic fowl. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Evolution of Gene Duplication in Plants1[OPEN

PubMed Central

2016-01-01

Ancient duplication events and a high rate of retention of extant pairs of duplicate genes have contributed to an abundance of duplicate genes in plant genomes. These duplicates have contributed to the evolution of novel functions, such as the production of floral structures, induction of disease resistance, and adaptation to stress. Additionally, recent whole-genome duplications that have occurred in the lineages of several domesticated crop species, including wheat (Triticum aestivum), cotton (Gossypium hirsutum), and soybean (Glycine max), have contributed to important agronomic traits, such as grain quality, fruit shape, and flowering time. Therefore, understanding the mechanisms and impacts of gene duplication will be important to future studies of plants in general and of agronomically important crops in particular. In this review, we survey the current knowledge about gene duplication, including gene duplication mechanisms, the potential fates of duplicate genes, models explaining duplicate gene retention, the properties that distinguish duplicate from singleton genes, and the evolutionary impact of gene duplication. PMID:27288366

The role of competition and seed production environment on the success of two perennial grass species in a roadside restoration

USDA-ARS?s Scientific Manuscript database

When large-scale restorations are undertaken using local genotypes, wild-collected sources often undergo a generation in an agronomic environment for seed increase. We have little information on how a single generation of agronomic production can alter seed success in restoration. In this study, we...

Evaluation of a new inference method for estimating ammonia volatilisation from multiple agronomic plots

NASA Astrophysics Data System (ADS)

Loubet, Benjamin; Carozzi, Marco; Voylokov, Polina; Cohan, Jean-Pierre; Trochard, Robert; Génermont, Sophie

2018-06-01

Tropospheric ammonia (NH3) is a threat to the environment and human health and is mainly emitted by agriculture. Ammonia volatilisation following application of nitrogen in the field accounts for more than 40 % of the total NH3 emissions in France. This represents a major loss of nitrogen use efficiency which needs to be reduced by appropriate agricultural practices. In this study we evaluate a novel method to infer NH3 volatilisation from small agronomic plots consisting of multiple treatments with repetition. The method is based on the combination of a set of NH3 diffusion sensors exposed for durations of 3 h to 1 week and a short-range atmospheric dispersion model, used to retrieve the emissions from each plot. The method is evaluated by mimicking NH3 emissions from an ensemble of nine plots with a resistance analogue-compensation point-surface exchange scheme over a yearly meteorological database separated into 28-day periods. A multifactorial simulation scheme is used to test the effects of sensor numbers and heights, plot dimensions, source strengths, and background concentrations on the quality of the inference method. We further demonstrate by theoretical considerations in the case of an isolated plot that inferring emissions with diffusion sensors integrating over daily periods will always lead to underestimations due to correlations between emissions and atmospheric transfer. We evaluated these underestimations as -8 % ± 6 % of the emissions for a typical western European climate. For multiple plots, we find that this method would lead to median underestimations of -16 % with an interquartile [-8-22 %] for two treatments differing by a factor of up to 20 and a control treatment with no emissions. We further evaluate the methodology for varying background concentrations and NH3 emissions patterns and demonstrate the low sensitivity of the method to these factors. The method was also tested in a real case and proved to provide sound evaluations of NH3

The importance of education in managing invasive plant species

USDA-ARS?s Scientific Manuscript database

Invasive plant species can establish in diverse environments and with the increase in human mobility, they are no longer restricted to isolated pockets in remote parts of the world. Cheat grass (Bromus tectorum L.) in rangelands, purple loosestrife (Lythrum salicaria L.) in wet lands and Canada this...

Contrasting agronomic response of biochar amendment to a Mediterranean Cambisol: Incubation vs. field experiment

NASA Astrophysics Data System (ADS)

De la Rosa, José M.; Paneque, Marina; De Celis, Reyes; Miller, Ana Z.; Knicker, Heike

2015-04-01

The application of biochar to soil is being proposed as a novel approach to establish a significant long-term sink for atmospheric carbon dioxide in terrestrial ecosystems. In addition, biochars offer a simple, sustainable tool for managing organic wastes and to produce added value products. Numerous research studies pointed out that biochar can act as a soil conditioner enhancing plant growth by supplying and, more importantly, retaining nutrients and by providing other services such as improving soil physical and biological properties [1]. However, the effectiveness of biochar in enhancing plant fertility is a function of soil type, climate, and type of crop [2] but also of the biochar properties. The inherent variability of biochars due to different feedstock and production conditions implies a high variability of their effect on soil properties and productivity. Furthermore, due to the irreversibility of biochar application, it is necessary to perform detailed studies to achieve a high level of certainty that adding biochar to agricultural soils, for whatever reason, will not negatively affect soil health and productivity. The major goals of this research were: i) understanding how the properties of 5 different biochars produced by using different feedstock and pyrolysis conditions are related to their agronomic response, and ii) assessing the agronomic effect of biochar amendment under field conditions of a typical Mediterranean non-irrigated plantation. Four of the used biochars were produced by pyrolysis from wood (2), paper sludge (1) and sewage sludge (1), at temperatures up to 620 °C. The fifth biochar was produced from old grapevine wood by applying the traditional kiln method. Biochars were analysed for elemental composition (C, H, N), pH, WHC and ash contents. The H/C and O/C atomic ratios suggested high aromaticity of all biochars, which was confirmed by 13C solid-state NMR spectroscopy. The FT-IR spectra indicated the presence of lignin residues in

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

Agronomic assessment of the wheat semi-dwarfing gene Rht8 in contrasting nitrogen treatments and water regimes

PubMed Central

Kowalski, Ania M.; Gooding, Mike; Ferrante, Ariel; Slafer, Gustavo A.; Orford, Simon; Gasperini, Debora; Griffiths, Simon

2016-01-01

Reduced height 8 (Rht8) is the main alternative to the GA-insensitive Rht alleles in hot and dry environments where it reduces plant height without yield penalty. The potential of Rht8 in northern-European wheat breeding remains unclear, since the close linkage with the photoperiod-insensitive allele Ppd-D1a is unfavourable in the relatively cool summers. In the present study, two near-isogenic lines (NILs) contrasting for the Rht8/tall allele from Mara in a UK-adapted and photoperiod-sensitive wheat variety were evaluated in trials with varying nitrogen fertiliser (N) treatments and water regimes across sites in the UK and Spain. The Rht8 introgression was associated with a robust height reduction of 11% regardless of N treatment and water regime and the Rht8 NIL was more resistant to root-lodging at agronomically-relevant N levels than the tall NIL. In the UK with reduced solar radiation over the growing season than the site in Spain, the Rht8 NIL showed a 10% yield penalty at standard agronomic N levels due to concomitant reduction in grain number and spike number whereas grain weight and harvest index were not significantly different to the tall NIL. The yield penalty associated with the Rht8 introgression was overcome at low N and in irrigated conditions in the UK, and in the high-temperature site in Spain. Decreased spike length and constant spikelet number in the Rht8 NIL resulted in spike compaction of 15%, independent of N and water regime. The genetic interval of Rht8 overlaps with the compactum gene on 2DS, raising the possibility of the same causative gene. Further genetic dissection of these loci is required. PMID:27212788

Bio-effectors from waste materials as growth promoters, an agronomic and metabolomic study

NASA Astrophysics Data System (ADS)

Alwanney, Deaa; Chami, Ziad Al; Angelica De Pascali, Sandra; Cavoski, Ivana; Fanizzi, Francesco Paolo

2014-05-01

Nowadays, improving plant performance by providing growth promoters is a main concern of the organic agriculture. As a consequence of increased food demands, more efficient and alternatives of the current plant nutrition strategies are becoming urgent. Recently, a novel concept "bio-effectors" raised on to describe a group of products that are able to improve plant performance and do not belong to fertilizers or pesticides. Agro-Food processing residues are promising materials as bio-effector. Three plant-derived materials: brewers' spent grain (BSG), fennel processing residues (FPR) and lemon processing residues (LPR) were chosen as bio-effector candidates. Plant-derived materials were characterized in term of total macro and micronutrients content. Green extraction methodology and solvent choice (aqueous; ethanol; and aqueous: ethanol mixture 1:1) was based on the extraction yield as main factor. Optimum extracts, to be used on the tomato test plant, were determined using phytotoxicity test (seed germination test) as main constraint. Thereafter, selected extracts were characterized and secondary metabolites profiling were detected by NMR technique. Selected extracts were applied on tomato in a growth chamber at different doses in comparison to humic-like substances as positive control (Ctrl+) and to a Hoagland solution as negative control (Ctrl-). At the end of the experiment, agronomical parameters were determined and NMR-metabolomic profiling were conducted on tomato seedlings. Results are summarized as follow: (i) raw showed an interesting content, either at nutritional or biological level; (ii) aqueous extraction resulted higher yield than other used solvent; (iii) at high extraction ratio (1:25 for BSG; 1:100 for FPR; and 1:200 for LPR) aqueous extracts were not phytotoxic on the tomato test plant; (iv) all aqueous extract are differently rich in nutrients, aminoacids, sugars and low molecular weight molecules; (v) all extract exhibited a growth promotion at

Genome-Wide Association Mapping for Yield and Other Agronomic Traits in an Elite Breeding Population of Tropical Rice (Oryza sativa)

PubMed Central

Lalusin, Antonio; Borromeo, Teresita; Gregorio, Glenn; Hernandez, Jose; Virk, Parminder; Collard, Bertrand; McCouch, Susan R.

2015-01-01

Genome-wide association mapping studies (GWAS) are frequently used to detect QTL in diverse collections of crop germplasm, based on historic recombination events and linkage disequilibrium across the genome. Generally, diversity panels genotyped with high density SNP panels are utilized in order to assay a wide range of alleles and haplotypes and to monitor recombination breakpoints across the genome. By contrast, GWAS have not generally been performed in breeding populations. In this study we performed association mapping for 19 agronomic traits including yield and yield components in a breeding population of elite irrigated tropical rice breeding lines so that the results would be more directly applicable to breeding than those from a diversity panel. The population was genotyped with 71,710 SNPs using genotyping-by-sequencing (GBS), and GWAS performed with the explicit goal of expediting selection in the breeding program. Using this breeding panel we identified 52 QTL for 11 agronomic traits, including large effect QTLs for flowering time and grain length/grain width/grain-length-breadth ratio. We also identified haplotypes that can be used to select plants in our population for short stature (plant height), early flowering time, and high yield, and thus demonstrate the utility of association mapping in breeding populations for informing breeding decisions. We conclude by exploring how the newly identified significant SNPs and insights into the genetic architecture of these quantitative traits can be leveraged to build genomic-assisted selection models. PMID:25785447

Response of citrus and other selected plant species to simulated HCL - acid rain

NASA Technical Reports Server (NTRS)

Knott, W. M.; Heagle, A. S.

1980-01-01

Mature valencia orange trees were sprayed with hydrochloric acid solutions (pH 7.8, 2.0, 1.0, and 0.5) in the field at the full bloom stage and at one month after fruit set. Potted valencia orange and dwarf citrus trees, four species of plants native to Merritt Island, and four agronomic species were exposed to various pH levels of simulated acid rain under controlled conditions. The acid rain was generated from dilutions of hydrochloric acid solutions or by passing water through an exhaust generated by burning solid rocket fuel. The plants were injured severely at pH levels below 1.0, but showed only slight injury at pH levels of 2.0 and above. Threshold injury levels were between 2.0 and 3.0 pH. The sensitivity of the different plant species to acid solutions was similar. Foliar injury symptoms were representative of acid rain including necrosis of young tissue, isolated necrotic spots or patches, and leaf abscission. Mature valencia orange trees sprayed with concentrations of 1.0 pH and 0.5 pH in the field had reduced fruit yields for two harvests after the treatment. All experimental trees were back to full productivity by the third harvest after treatment.

Important Hawaiian tree species in need of genetic conservation

Treesearch

Robert D. Hauff

2017-01-01

Resource managers in Hawaii face unique forest conservation challenges. Invasive species continue to inundate the remote island archipelago, directly threatening its forest resources. Hawaii has the largest number (> 400) of endangered plants in the United States, and managers use genetic approaches to preserve these small populations which are often island...

When Ontogeny Matters: A New Japanese Species of Brittle Star Illustrates the Importance of Considering both Adult and Juvenile Characters in Taxonomic Practice.

PubMed

Martynov, Alexander; Ishida, Yoshiaki; Irimura, Seiichi; Tajiri, Rie; O'Hara, Timothy; Fujita, Toshihiko

2015-01-01

Current taxonomy offers numerous approaches and methods for species delimitation and description. However, most of them are based on the adult characters and rarely suggest a dynamic representation of developmental transformations of taxonomically important features. Here we show how the underestimation of ontogenetic changes may result in long term lack of recognition of a new species of one of the most common ophiacanthid brittle stars (Echinodermata: Ophiuroidea) from the North Pacific. Based on vast material collected predominantly by various Japanese expeditions in the course of more than 50 years, and thorough study of appropriate type material, we revise the complex of three common species of the ophiuroid genus Ophiacantha which have been persistently confused with each other. The present study thus reveals the previously unrecognized new species Ophiacantha kokusai sp.nov. which is commonly distributed off the Pacific coast of Japan. The new species shows developmental differentiation from the closely related species Ophiacantha rhachophora H. L. Clark, 1911 and retains clearly expressed early juvenile features in the adult morphology. Another species, Ophiacantha clypeata Kyte, 1977, which had been separated from O. rhachophora, is in turn shown to be just a juvenile stage of another North Pacific species, Ophiacantha trachybactra H.L. Clark, 1911. For every species, detailed morphological data from both adult and juvenile specimens based on scanning electron microscopy are presented. A special grinding method showing complex internal features has been utilized for the first time. For all three species in this complex, a clear bathymetric differentiation is revealed: O. rhachophora predominantly inhabits shallow waters, 0-250 m, the new species O. kokusai lives deeper, at 250-600 m, and the third species, O. trachybactra, is found at 500-2,000 m. The present case clearly highlights the importance of considering developmental transformations, not only for

Evaluating Functional Diversity: Missing Trait Data and the Importance of Species Abundance Structure and Data Transformation

PubMed Central

Bryndová, Michala; Kasari, Liis; Norberg, Anna; Weiss, Matthias; Bishop, Tom R.; Luke, Sarah H.; Sam, Katerina; Le Bagousse-Pinguet, Yoann; Lepš, Jan; Götzenberger, Lars; de Bello, Francesco

2016-01-01

Functional diversity (FD) is an important component of biodiversity that quantifies the difference in functional traits between organisms. However, FD studies are often limited by the availability of trait data and FD indices are sensitive to data gaps. The distribution of species abundance and trait data, and its transformation, may further affect the accuracy of indices when data is incomplete. Using an existing approach, we simulated the effects of missing trait data by gradually removing data from a plant, an ant and a bird community dataset (12, 59, and 8 plots containing 62, 297 and 238 species respectively). We ranked plots by FD values calculated from full datasets and then from our increasingly incomplete datasets and compared the ranking between the original and virtually reduced datasets to assess the accuracy of FD indices when used on datasets with increasingly missing data. Finally, we tested the accuracy of FD indices with and without data transformation, and the effect of missing trait data per plot or per the whole pool of species. FD indices became less accurate as the amount of missing data increased, with the loss of accuracy depending on the index. But, where transformation improved the normality of the trait data, FD values from incomplete datasets were more accurate than before transformation. The distribution of data and its transformation are therefore as important as data completeness and can even mitigate the effect of missing data. Since the effect of missing trait values pool-wise or plot-wise depends on the data distribution, the method should be decided case by case. Data distribution and data transformation should be given more careful consideration when designing, analysing and interpreting FD studies, especially where trait data are missing. To this end, we provide the R package “traitor” to facilitate assessments of missing trait data. PMID:26881747

Evaluating Functional Diversity: Missing Trait Data and the Importance of Species Abundance Structure and Data Transformation.

PubMed

Májeková, Maria; Paal, Taavi; Plowman, Nichola S; Bryndová, Michala; Kasari, Liis; Norberg, Anna; Weiss, Matthias; Bishop, Tom R; Luke, Sarah H; Sam, Katerina; Le Bagousse-Pinguet, Yoann; Lepš, Jan; Götzenberger, Lars; de Bello, Francesco

2016-01-01

Functional diversity (FD) is an important component of biodiversity that quantifies the difference in functional traits between organisms. However, FD studies are often limited by the availability of trait data and FD indices are sensitive to data gaps. The distribution of species abundance and trait data, and its transformation, may further affect the accuracy of indices when data is incomplete. Using an existing approach, we simulated the effects of missing trait data by gradually removing data from a plant, an ant and a bird community dataset (12, 59, and 8 plots containing 62, 297 and 238 species respectively). We ranked plots by FD values calculated from full datasets and then from our increasingly incomplete datasets and compared the ranking between the original and virtually reduced datasets to assess the accuracy of FD indices when used on datasets with increasingly missing data. Finally, we tested the accuracy of FD indices with and without data transformation, and the effect of missing trait data per plot or per the whole pool of species. FD indices became less accurate as the amount of missing data increased, with the loss of accuracy depending on the index. But, where transformation improved the normality of the trait data, FD values from incomplete datasets were more accurate than before transformation. The distribution of data and its transformation are therefore as important as data completeness and can even mitigate the effect of missing data. Since the effect of missing trait values pool-wise or plot-wise depends on the data distribution, the method should be decided case by case. Data distribution and data transformation should be given more careful consideration when designing, analysing and interpreting FD studies, especially where trait data are missing. To this end, we provide the R package "traitor" to facilitate assessments of missing trait data.

Niche Partitioning in Three Sympatric Congeneric Species of Dragonfly, Orthetrum chrysostigma, O. coerulescens anceps, and O. nitidinerve: The Importance of Microhabitat

PubMed Central

Khelifa, Rassim; Zebsa, Rabah; Moussaoui, Abdelkrim; Kahalerras, Amin; Bensouilah, Soufyane; Mahdjoub, Hayat

2013-01-01

Habitat heterogeneity has been shown to promote co-existence of closely related species. Based on this concept, a field study was conducted on the niche partitioning of three territorial congeneric species of skimmers (Anisoptera: Libellulidae) in Northeast Algeria during the breeding season of 2011. According to their size, there is a descending hierarchy between Orthetrum nitidinerve Sélys, O. chrysostigma (Burmeister), and O. coerulescens anceps (Schneider). After being marked and surveyed, the two latter species had the same breeding behavior sequence. Knowing that they had almost the same size, such species could not co-occur in the same habitat according to the competitive exclusion principle. The spatial distribution of the three species was investigated at two different microhabitats, and it was found that these two species were actually isolated at this scale. O. chrysostigma and O. nitidinerve preferred open areas, while O. c. anceps occurred in highly vegetated waters. This study highlights the role of microhabitat in community structure as an important niche axis that maintains closely related species in the same habitat. PMID:24219357

Synthesis and chemical characterization of the novel agronomically relevant pentadentate chelate 2-(2-((2-hydroxybenzyl)amino)ethylamino)-2-(2-hydroxyphenyl)acetic acid (DCHA).

PubMed

López-Rayo, Sandra; Hernández, Diana; Lucena, Juan J; Escudero, Rosa; Gómez-Gallego, Mar; Sierra, Miguel A

2010-07-14

Iron chelates analogous to o,o-EDDHA/Fe(3+) are the fertilizers chosen to treat iron chlorosis in plants growing on calcareous soil. The isomer o,p-EDDHA/Fe(3+) presents less stability but faster assimilation by the plant than o,o-EDDHA/Fe(3+), because only five coordinating groups are able to complex Fe(3+). The new chelating agent 2-(2-((2-hydroxybenzyl)amino)ethylamino)-2-(2-hydroxyphenyl)acetic acid (DCHA) has been synthesized to obtain an iron fertilizer with intermediate stability between o,o-EDDHA/Fe(3+) and o,p-EDDHA/Fe(3+) and with fast assimilation. Its synthesis has been done starting from phenol, N-acetylethylendiamine, glyoxylic acid, and NaOH in a three-step sequence. The purity of the DCHA chelating agent, its protonation, and Ca(2+), Mg(2+), Fe(3+), and Cu(2+) stability constants, together with its ability to maintain iron in solution in different agronomic conditions, have been determined. The results indicate that the chelate DCHA/Fe(3+) has intermediate stability between those of o,o-EDDHA/Fe(3+) and o,p-EDDHA/Fe(3+) complexes and that it is capable of maintaining the Fe(3+) in agronomic conditions. This new chelating agent may be effective in correcting iron chlorosis in plants.

Patterns of Z chromosome divergence among Heliconius species highlight the importance of historical demography.

PubMed

Van Belleghem, Steven M; Baquero, Margarita; Papa, Riccardo; Salazar, Camilo; McMillan, W Owen; Counterman, Brian A; Jiggins, Chris D; Martin, Simon H

2018-03-22

Sex chromosomes are disproportionately involved in reproductive isolation and adaptation. In support of such a "large-X" effect, genome scans between recently diverged populations and species pairs often identify distinct patterns of divergence on the sex chromosome compared to autosomes. When measures of divergence between populations are higher on the sex chromosome compared to autosomes, such patterns could be interpreted as evidence for faster divergence on the sex chromosome, that is "faster-X", barriers to gene flow on the sex chromosome. However, demographic changes can strongly skew divergence estimates and are not always taken into consideration. We used 224 whole-genome sequences representing 36 populations from two Heliconius butterfly clades (H. erato and H. melpomene) to explore patterns of Z chromosome divergence. We show that increased divergence compared to equilibrium expectations can in many cases be explained by demographic change. Among Heliconius erato populations, for instance, population size increase in the ancestral population can explain increased absolute divergence measures on the Z chromosome compared to the autosomes, as a result of increased ancestral Z chromosome genetic diversity. Nonetheless, we do identify increased divergence on the Z chromosome relative to the autosomes in parapatric or sympatric species comparisons that imply postzygotic reproductive barriers. Using simulations, we show that this is consistent with reduced gene flow on the Z chromosome, perhaps due to greater accumulation of incompatibilities. Our work demonstrates the importance of taking demography into account to interpret patterns of divergence on the Z chromosome, but nonetheless provides evidence to support the Z chromosome as a strong barrier to gene flow in incipient Heliconius butterfly species. © 2018 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Mining the transcriptomes of four commercially important shellfish species for single nucleotide polymorphisms within biomineralization genes.

PubMed

Vendrami, David L J; Shah, Abhijeet; Telesca, Luca; Hoffman, Joseph I

2016-06-01

Transcriptional profiling not only provides insights into patterns of gene expression, but also generates sequences that can be mined for molecular markers, which in turn can be used for population genetic studies. As part of a large-scale effort to better understand how commercially important European shellfish species may respond to ocean acidification, we therefore mined the transcriptomes of four species (the Pacific oyster Crassostrea gigas, the blue mussel Mytilus edulis, the great scallop Pecten maximus and the blunt gaper Mya truncata) for single nucleotide polymorphisms (SNPs). Illumina data for C. gigas, M. edulis and P. maximus and 454 data for M. truncata were interrogated using GATK and SWAP454 respectively to identify between 8267 and 47,159 high quality SNPs per species (total=121,053 SNPs residing within 34,716 different contigs). We then annotated the transcripts containing SNPs to reveal homology to diverse genes. Finally, as oceanic pH affects the ability of organisms to incorporate calcium carbonate, we honed in on genes implicated in the biomineralization process to identify a total of 1899 SNPs in 157 genes. These provide good candidates for biomarkers with which to study patterns of selection in natural or experimental populations. Copyright © 2016 Elsevier B.V. All rights reserved.

Diatoms can be an important exception to temperature-size rules at species and community levels of organization.

PubMed

Adams, Georgina L; Pichler, Doris E; Cox, Eileen J; O'Gorman, Eoin J; Seeney, Alex; Woodward, Guy; Reuman, Daniel C

2013-11-01

Climate warming has been linked to an apparent general decrease in body sizes of ectotherms, both across and within taxa, especially in aquatic systems. Smaller body size in warmer geographical regions has also been widely observed. Since body size is a fundamental determinant of many biological attributes, climate-warming-related changes in size could ripple across multiple levels of ecological organization. Some recent studies have questioned the ubiquity of temperature-size rules, however, and certain widespread and abundant taxa, such as diatoms, may be important exceptions. We tested the hypothesis that diatoms are smaller at warmer temperatures using a system of geothermally heated streams. There was no consistent relationship between size and temperature at either the population or community level. These field data provide important counterexamples to both James' and Bergmann's temperature-size rules, respectively, undermining the widely held assumption that warming favours the small. This study provides compelling new evidence that diatoms are an important exception to temperature-size rules for three reasons: (i) we use many more species than prior work; (ii) we examine both community and species levels of organization simultaneously; (iii) we work in a natural system with a wide temperature gradient but minimal variation in other factors, to achieve robust tests of hypotheses without relying on laboratory setups, which have limited realism. In addition, we show that interspecific effects were a bigger contributor to whole-community size differences, and are probably more ecologically important than more commonly studied intraspecific effects. These findings highlight the need for multispecies approaches in future studies of climate warming and body size. © 2013 John Wiley & Sons Ltd.

Diatoms can be an important exception to temperature–size rules at species and community levels of organization

PubMed Central

Adams, Georgina L; Pichler, Doris E; Cox, Eileen J; O'Gorman, Eoin J; Seeney, Alex; Woodward, Guy; Reuman, Daniel C

2013-01-01

Climate warming has been linked to an apparent general decrease in body sizes of ectotherms, both across and within taxa, especially in aquatic systems. Smaller body size in warmer geographical regions has also been widely observed. Since body size is a fundamental determinant of many biological attributes, climate-warming-related changes in size could ripple across multiple levels of ecological organization. Some recent studies have questioned the ubiquity of temperature–size rules, however, and certain widespread and abundant taxa, such as diatoms, may be important exceptions. We tested the hypothesis that diatoms are smaller at warmer temperatures using a system of geothermally heated streams. There was no consistent relationship between size and temperature at either the population or community level. These field data provide important counterexamples to both James’ and Bergmann's temperature–size rules, respectively, undermining the widely held assumption that warming favours the small. This study provides compelling new evidence that diatoms are an important exception to temperature–size rules for three reasons: (i) we use many more species than prior work; (ii) we examine both community and species levels of organization simultaneously; (iii) we work in a natural system with a wide temperature gradient but minimal variation in other factors, to achieve robust tests of hypotheses without relying on laboratory setups, which have limited realism. In addition, we show that interspecific effects were a bigger contributor to whole-community size differences, and are probably more ecologically important than more commonly studied intraspecific effects. These findings highlight the need for multispecies approaches in future studies of climate warming and body size. PMID:23749600

Gimme shelter: The importance of crevices to some fish species inhabiting a deeper-water rocky outcrop in Southern California

USGS Publications Warehouse

Love, M.S.; Schroeder, D.M.; Lenarz, B.; Cochrane, G.R.

2006-01-01

Federal law governing fisheries management recognizes the role habitat plays in structuring fish assemblages and achieving sustainable fisheries. However, in most instances it is not known which aspects of habitat are important to the lives of fish species. In 2004, we examined the importance of sheltering sites (crevices) to fishes living along low ledges in deeper waters off Anacapa Island, southern California. We found that patterns of fish-habitat relationships varied among the eight most abundant species. Three species, bocaccio (Sebastes paucispinis), vermilion (S. miniatus), and flag (S. rubrivinctus) rockfishes, had densities one to three orders of magnitude greater in the deep crevice habitat compared to low relief rock or shallow crevice habitats. Density and mean size of the two most abundant fishes, halfbanded (S. semicinctus) and squarespot (S. hopkinsi) rockfishes, generally increased as complexity of rock habitat increased. Not all species had the highest densities in deep crevice habitat. Greenspotted rockfish (S. chlorostictus) and blackeye goby (Rhinogobiops nicholsii) showed no significant difference in density among rock habitats. Pink seaperch (Zalembius rosaceus) were absent in the deep crevice habitat and abundant only in low relief rock habitats. Our study implies that it is not sufficient to distinguish only between soft and hard bottom types when using habitat to guide fisheries management strategies. Finer-scale investigations of fish-habitat relationships, paired with habitat mapping and groundtruthing, aid in the design and positioning of Marine Park Areas (MPAs) and are necessary to facilitate understanding of how a particular MPA may contribute to fisheries management.

The historical role of species from the Solanaceae plant family in genetic research.

PubMed

Gebhardt, Christiane

2016-12-01

This article evaluates the main contributions of tomato, tobacco, petunia, potato, pepper and eggplant to classical and molecular plant genetics and genomics since the beginning of the twentieth century. Species from the Solanaceae family form integral parts of human civilizations as food sources and drugs since thousands of years, and, more recently, as ornamentals. Some Solanaceous species were subjects of classical and molecular genetic research over the last 100 years. The tomato was one of the principal models in twentieth century classical genetics and a pacemaker of genome analysis in plants including molecular linkage maps, positional cloning of disease resistance genes and quantitative trait loci (QTL). Besides that, tomato is the model for the genetics of fruit development and composition. Tobacco was the major model used to establish the principals and methods of plant somatic cell genetics including in vitro propagation of cells and tissues, totipotency of somatic cells, doubled haploid production and genetic transformation. Petunia was a model for elucidating the biochemical and genetic basis of flower color and development. The cultivated potato is the economically most important Solanaceous plant and ranks third after wheat and rice as one of the world's great food crops. Potato is the model for studying the genetic basis of tuber development. Molecular genetics and genomics of potato, in particular association genetics, made valuable contributions to the genetic dissection of complex agronomic traits and the development of diagnostic markers for breeding applications. Pepper and eggplant are horticultural crops of worldwide relevance. Genetic and genomic research in pepper and eggplant mostly followed the tomato model. Comparative genome analysis of tomato, potato, pepper and eggplant contributed to the understanding of plant genome evolution.

Identification of loci governing eight agronomic traits using a GBS-GWAS approach and validation by QTL mapping in soya bean.

PubMed

Sonah, Humira; O'Donoughue, Louise; Cober, Elroy; Rajcan, Istvan; Belzile, François

2015-02-01

Soya bean is a major source of edible oil and protein for human consumption as well as animal feed. Understanding the genetic basis of different traits in soya bean will provide important insights for improving breeding strategies for this crop. A genome-wide association study (GWAS) was conducted to accelerate molecular breeding for the improvement of agronomic traits in soya bean. A genotyping-by-sequencing (GBS) approach was used to provide dense genome-wide marker coverage (>47,000 SNPs) for a panel of 304 short-season soya bean lines. A subset of 139 lines, representative of the diversity among these, was characterized phenotypically for eight traits under six environments (3 sites × 2 years). Marker coverage proved sufficient to ensure highly significant associations between the genes known to control simple traits (flower, hilum and pubescence colour) and flanking SNPs. Between one and eight genomic loci associated with more complex traits (maturity, plant height, seed weight, seed oil and protein) were also identified. Importantly, most of these GWAS loci were located within genomic regions identified by previously reported quantitative trait locus (QTL) for these traits. In some cases, the reported QTLs were also successfully validated by additional QTL mapping in a biparental population. This study demonstrates that integrating GBS and GWAS can be used as a powerful complementary approach to classical biparental mapping for dissecting complex traits in soya bean. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Correlations and path analysis among agronomic and technological traits of upland cotton.

PubMed

Farias, F J C; Carvalho, L P; Silva Filho, J L; Teodoro, P E

2016-08-12

To date, path analysis has been used with the aim of breeding different cultures. However, for cotton, there have been few studies using this analysis, and all of these have used fiber productivity as the primary dependent variable. Therefore, the aim of the present study was to identify agronomic and technological properties that can be used as criteria for direct and indirect phenotypes in selecting cotton genotypes with better fibers. We evaluated 16 upland cotton genotypes in eight trials conducted during the harvest 2008/2009 in the State of Mato Grosso, using a randomized block design with four replicates. The evaluated traits were: plant height, average boll weight, percentage of fiber, cotton seed yield, fiber length, uniformity of fiber, short fiber index, fiber strength, elongation, maturity of the fibers, micronaire, reflectance, and the degree of yellowing. Phenotypic correlations between the traits and cotton fiber yield (main dependent variable) were unfolded in direct and indirect effects through path analysis. Fiber strength, uniformity of fiber, and reflectance were found to influence fiber length, and therefore, these traits are recommended for both direct and indirect selection of cotton genotypes.

Shotgun proteomic analysis of Emiliania huxleyi, a marine phytoplankton species of major biogeochemical importance.

PubMed

Jones, Bethan M; Edwards, Richard J; Skipp, Paul J; O'Connor, C David; Iglesias-Rodriguez, M Debora

2011-06-01

Emiliania huxleyi is a unicellular marine phytoplankton species known to play a significant role in global biogeochemistry. Through the dual roles of photosynthesis and production of calcium carbonate (calcification), carbon is transferred from the atmosphere to ocean sediments. Almost nothing is known about the molecular mechanisms that control calcification, a process that is tightly regulated within the cell. To initiate proteomic studies on this important and phylogenetically remote organism, we have devised efficient protein extraction protocols and developed a bioinformatics pipeline that allows the statistically robust assignment of proteins from MS/MS data using preexisting EST sequences. The bioinformatics tool, termed BUDAPEST (Bioinformatics Utility for Data Analysis of Proteomics using ESTs), is fully automated and was used to search against data generated from three strains. BUDAPEST increased the number of identifications over standard protein database searches from 37 to 99 proteins when data were amalgamated. Proteins involved in diverse cellular processes were uncovered. For example, experimental evidence was obtained for a novel type I polyketide synthase and for various photosystem components. The proteomic and bioinformatic approaches developed in this study are of wider applicability, particularly to the oceanographic community where genomic sequence data for species of interest are currently scarce.

Cereal grass pulvini: agronomically significant models for studying gravitropism signaling and tissue polarity.

PubMed

Clore, Amy M

2013-01-01

Cereal grass pulvini have emerged as model systems that are not only valuable for the study of gravitropism, but are also of agricultural and economic significance. The pulvini are regions of tissue that are apical to each node and collectively return a reoriented stem to a more vertical position. They have proven to be useful for the study of gravisensing and response and are also providing clues about the establishment of polarity across tissues. This review will first highlight the agronomic significance of these stem regions and their benefits for use as model systems and provide a brief historical overview. A detailed discussion of the literature focusing on cell signaling and early changes in gene expression will follow, culminating in a temporal framework outlining events in the signaling and early growth phases of gravitropism in this tissue. Changes in cell wall composition and gene expression that occur well into the growth phase will be touched upon briefly. Finally, some ongoing research involving both maize and wheat pulvini will be introduced along with prospects for future investigations.

Species mixture effects on flammability across plant phylogeny: the importance of litter particle size and the special role for non-Pinus Pinaceae.

PubMed

Zhao, Weiwei; Cornwell, William K; van Pomeren, Marinda; van Logtestijn, Richard S P; Cornelissen, Johannes H C

2016-11-01

Fire affects and is affected by plants. Vegetation varies in flammability, that is, its general ability to burn, at different levels of ecological organization. To scale from individual plant traits to community flammability states, understanding trait effects on species flammability variation and their interaction is important. Plant traits are the cumulative result of evolution and they show, to differing extents, phylogenetic conservatism. We asked whether phylogenetic distance between species predicts species mixture effects on litterbed flammability. We conducted controlled laboratory burns for 34 phylogenetically wide-ranging species and 34 random two-species mixtures from them. Generally, phylogenetic distance did not predict species mixture effects on flammability. Across the plant phylogeny, most species were flammable except those in the non- Pinus Pinaceae, which shed small needles producing dense, poorly ventilated litterbeds above the packing threshold and therefore nonflammable. Consistently, either positive or negative dominance effects on flammability of certain flammable or those non-flammable species were found in mixtures involving the non- Pinus Pinaceae. We demonstrate litter particle size is key to explaining species nonadditivity in fuelbed flammability. The potential of certain species to influence fire disproportionately to their abundance might increase the positive feedback effects of plant flammability on community flammability state if flammable species are favored by fire.

Differentiation of aflatoxigenic and non-aflatoxigenic strains of Aspergilli by FT-IR spectroscopy.

PubMed

Atkinson, Curtis; Pechanova, Olga; Sparks, Darrell L; Brown, Ashli; Rodriguez, Jose M

2014-01-01

Fourier transform infrared spectroscopy (FT-IR) is a well-established and widely accepted methodology to identify and differentiate diverse microbial species. In this study, FT-IR was used to differentiate 20 strains of ubiquitous and agronomically important phytopathogens of Aspergillus flavus and Aspergillus parasiticus. By analyzing their spectral profiles via principal component and cluster analysis, differentiation was achieved between the aflatoxin-producing and nonproducing strains of both fungal species. This study thus indicates that FT-IR coupled to multivariate statistics can rapidly differentiate strains of Aspergilli based on their toxigenicity.

Characterization and susceptibility patterns of clinically important Enterococcus species in eastern Nepal.

PubMed

Acharya, A; Khanal, A; Kanungo, R; Mohapatra, T

2007-12-01

Life threatening infections caused by enterococcus species with multidrug resistance has emerged as a threat to medical care in the present era. This study was conducted to characterize enterococcus species isolated from different clinical samples and to detect the pattern of susceptibility to some of the commonly used antibiotics in B.P Koirala Institute of Health Sciences (BPKIHS), a tertiary care hospital in eastern Nepal. Clinical samples submitted to the microbiology unit of Central Laboratory Service (CLS) for culture and sensitivity during March 2002 - February 2003 was analyzed. Enterococcus species were identified by colony characteristics, gram staining and relevant biochemical tests. Antibiotic susceptibility test was done by the Kirby Bauer disc diffusion technique. Of 50 Enterococcus species isolated, E. faecalis was the predominant isolate (48.0%) followed by E. faecium (32.0%) and E. avium (20.0%). Eighty-eight percent of E. faecalis showed sensitivity to cephotaxime and 87.0% to vancomycin. Multiple drug resistance was observed most commonly in E. faecium. Seventeen percent of E. faecium were resistant to vancomycin and 63.0% to ciprofloxacin and 44.0% to ampicillin. On the contrary E. avium rarely showed resistance to the antimicrobials tested including vancomycin. Enterococcal infections are common nowadays specially in hospitalized patients. Inappropriate use of antibiotics in clinical practice and poultry should be discouraged to prevent the emergence of multidrug resistant species.

The Slugs of Britain and Ireland: Undetected and Undescribed Species Increase a Well-Studied, Economically Important Fauna by More Than 20%

PubMed Central

Rowson, Ben; Anderson, Roy; Turner, James A.; Symondson, William O. C.

2014-01-01

The slugs of Britain and Ireland form a well-studied fauna of economic importance. They include many widespread European species that are introduced elsewhere (at least half of the 36 currently recorded British species are established in North America, for example). To test the contention that the British and Irish fauna consists of 36 species, and to verify the identity of each, a species delimitation study was conducted based on a geographically wide survey. Comparisons between mitochondrial DNA (COI, 16S), nuclear DNA (ITS-1) and morphology were investigated with reference to interspecific hybridisation. Species delimitation of the fauna produced a primary species hypothesis of 47 putative species. This was refined to a secondary species hypothesis of 44 species by integration with morphological and other data. Thirty six of these correspond to the known fauna (two species in Arion subgenus Carinarion were scarcely distinct and Arion (Mesarion) subfuscus consisted of two near-cryptic species). However, by the same criteria a further eight previously undetected species (22% of the fauna) are established in Britain and/or Ireland. Although overlooked, none are strictly morphologically cryptic, and some appear previously undescribed. Most of the additional species are probably accidentally introduced, and several are already widespread in Britain and Ireland (and thus perhaps elsewhere). At least three may be plant pests. Some evidence was found for interspecific hybridisation among the large Arion species (although not involving A. flagellus) and more unexpectedly in species pairs in Deroceras (Agriolimacidae) and Limacus (Limacidae). In the latter groups, introgression appears to have occurred in one direction only, with recently-invading lineages becoming common at the expense of long-established or native ones. The results show how even a well-studied, macroscopic fauna can be vulnerable to cryptic and undetected invasions and changes. PMID:24740519

Characterization of the transcriptome of an ecologically important avian species, the Vinous-throated Parrotbill Paradoxornis webbianus bulomachus (Paradoxornithidae; Aves)

PubMed Central

2012-01-01

Background Adaptive divergence driven by environmental heterogeneity has long been a fascinating topic in ecology and evolutionary biology. The study of the genetic basis of adaptive divergence has, however, been greatly hampered by a lack of genomic information. The recent development of transcriptome sequencing provides an unprecedented opportunity to generate large amounts of genomic data for detailed investigations of the genetics of adaptive divergence in non-model organisms. Herein, we used the Illumina sequencing platform to sequence the transcriptome of brain and liver tissues from a single individual of the Vinous-throated Parrotbill, Paradoxornis webbianus bulomachus, an ecologically important avian species in Taiwan with a wide elevational range of sea level to 3100 m. Results Our 10.1 Gbp of sequences were first assembled based on Zebra Finch (Taeniopygia guttata) and chicken (Gallus gallus) RNA references. The remaining reads were then de novo assembled. After filtering out contigs with low coverage (<10X), we retained 67,791 of 487,336 contigs, which covered approximately 5.3% of the P. w. bulomachus genome. Of 7,779 contigs retained for a top-hit species distribution analysis, the majority (about 86%) were matched to known Zebra Finch and chicken transcripts. We also annotated 6,365 contigs to gene ontology (GO) terms: in total, 122 GO-slim terms were assigned, including biological process (41%), molecular function (32%), and cellular component (27%). Many potential genetic markers for future adaptive genomic studies were also identified: 8,589 single nucleotide polymorphisms, 1,344 simple sequence repeats and 109 candidate genes that might be involved in elevational or climate adaptation. Conclusions Our study shows that transcriptome data can serve as a rich genetic resource, even for a single run of short-read sequencing from a single individual of a non-model species. This is the first study providing transcriptomic information for species in the

Boron toxicity characteristics of four northern California endemic tree species

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

Glaubig, B.A.; Bingham, F.T.

A greenhouse study was undertaken to determine the characteristics of soil B toxicity for four tree species endemic to The Geysers area in northern California: digger pine (Pinus sabiniana Dougl. ex D. Don), California laurel (or, California bay) (Umbellularia californica (Hoo. and Arn. Nutt.)), madrone (Arbutus menziesii Pursh), and bigleaf maple (Acer macrophyllum Pursh). Significant exponential relationships were found between soil B concentration and relative growth, and between tissue B concentration and relative growth for the four species. Significant linear relationships were found between both soil and tissue B concentration and foliar damage for the four species. Foliar damages overmore » 25% of the leaf or needle area on digger pine, California laurel, madrone, and bigleaf maple, respectively, occurred at saturated soil extract concentrations (mmol B/L) of 1.2, 0.4, 0.5, and 0.08. Twenty-five percent foliar damage was associated with leaf or needle tissue concentrations (mmol B/kg) of 115, 100, 50, and 30 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Growth decrements of 25% occurred at saturated soil extract concentrations (mmol B/L) of 1.6, 0.3, 0.2, 0.5 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. Twenty-five percent growth decrements were associated with leaf or needle tissue concentrations (mmol B/kg) of 140, 100, 20, and 7 for the digger pine, California laurel, madrone, and bigleaf maple, respectively. By comparison with two agronomic crops - cotton (Gossypium hirsutum L.) and cowpea (Vigna unguiculata L.) - the four tree species were placed into one of six B tolerance classes.« less

Likeability of Garden Birds: Importance of Species Knowledge & Richness in Connecting People to Nature.

PubMed

Cox, Daniel T C; Gaston, Kevin J

2015-01-01

Interacting with nature is widely recognised as providing many health and well-being benefits. As people live increasingly urbanised lifestyles, the provision of food for garden birds may create a vital link for connecting people to nature and enabling them to access these benefits. However, it is not clear which factors determine the pleasure that people receive from watching birds at their feeders. These may be dependent on the species that are present, the abundance of individuals and the species richness of birds around the feeders. We quantitatively surveyed urban households from towns in southern England to determine the factors that influence the likeability of 14 common garden bird species, and to assess whether people prefer to see a greater abundance of individuals or increased species richness at their feeders. There was substantial variation in likeability across species, with songbirds being preferred over non-songbirds. Species likeability increased for people who fed birds regularly and who could name the species. We found a strong correlation between the number of species that a person could correctly identify and how connected to nature they felt when they watched garden birds. Species richness was preferred over a greater number of individuals of the same species. Although we do not show causation this study suggests that it is possible to increase the well-being benefits that people gain from watching birds at their feeders. This could be done first through a human to bird approach by encouraging regular interactions between people and their garden birds, such as through learning the species names and providing food. Second, it could be achieved through a bird to human approach by increasing garden songbird diversity because the pleasure that a person receives from watching an individual bird at a feeder is dependent not only on its species but also on the diversity of birds at the feeder.

Likeability of Garden Birds: Importance of Species Knowledge & Richness in Connecting People to Nature

PubMed Central

Cox, Daniel T. C.; Gaston, Kevin J.

2015-01-01

Interacting with nature is widely recognised as providing many health and well-being benefits. As people live increasingly urbanised lifestyles, the provision of food for garden birds may create a vital link for connecting people to nature and enabling them to access these benefits. However, it is not clear which factors determine the pleasure that people receive from watching birds at their feeders. These may be dependent on the species that are present, the abundance of individuals and the species richness of birds around the feeders. We quantitatively surveyed urban households from towns in southern England to determine the factors that influence the likeability of 14 common garden bird species, and to assess whether people prefer to see a greater abundance of individuals or increased species richness at their feeders. There was substantial variation in likeability across species, with songbirds being preferred over non-songbirds. Species likeability increased for people who fed birds regularly and who could name the species. We found a strong correlation between the number of species that a person could correctly identify and how connected to nature they felt when they watched garden birds. Species richness was preferred over a greater number of individuals of the same species. Although we do not show causation this study suggests that it is possible to increase the well-being benefits that people gain from watching birds at their feeders. This could be done first through a human to bird approach by encouraging regular interactions between people and their garden birds, such as through learning the species names and providing food. Second, it could be achieved through a bird to human approach by increasing garden songbird diversity because the pleasure that a person receives from watching an individual bird at a feeder is dependent not only on its species but also on the diversity of birds at the feeder. PMID:26560968

Using FIA data to assess current and potential future tree species importance values in the eastern United States

Treesearch

Louis Iverson; Anantha Prasad; Anantha Prasad

2003-01-01

FIA data are extremely valuable for evaluating regional variation in forest distribution. We have processed and summarized FIA data to show four patterns across the Eastern United States: 1) the number and density of FIA forested plots by state, 2) current importance values and frequencies for several species within 20 x 20 km blocks, 3) tree diversity by block, and 4...

Using FIA data to assess current and potential future tree species importance values in the eastern United States

Treesearch

Louis Iverson; Anantha Prasad

2002-01-01

FIA data are extremely valuable for evaluating regional variation in forest distribution. We have processed and summarized FIA data to show four patterns across the Eastern United States: 1) the number and density of FIA forested plots by state, 2) current importance values and frequencies for several species within 20 x 20 km blocks, 3) tree diversity by block, and 4...

QTLs for important breeding characteristics in the doubled haploid oat progeny.

PubMed

Tanhuanpää, Pirjo; Manninen, Outi; Kiviharju, Elina

2010-06-01

A homozygous mapping population, consisting of doubled haploid (DH) oat (Avena sativa L.) plants generated through anther culture of F1 plants from the cross between the Finnish cultivar 'Aslak' and the Swedish cultivar 'Matilda', was used to construct an oat linkage map. Ten agronomic and quality traits were analyzed in the DH plants from field trials in 2005 and 2006. Leaf blotch (caused by Pyrenophora avenae) resistance was also evaluated in a greenhouse test with 2 different isolates. One to 8 quantitative trait loci (QTLs) were found to be associated with each trait studied. Some chromosomal regions affected more than 1 trait; for example, 4 regions affected both protein and oil content. This study gives valuable information to oat breeders concerning the inheritance of important traits, and it provides potential tools to assist breeding.

Vulnerability assessment of New Jersey's food supply to invasive species: the New Jersey IMPORT project.

PubMed

Gregory, Petros; Hamilton, George; Borjan, Marija; Robson, Mark

2006-01-01

The United States' environment and economy have been severely impacted by unintentionally introduced biological organisms for the last 100 years. Our ecosystems and biological reserves of conservation importance are regularly invaded by non-indigenous species. To help prevent future invaders from entering the ports, this project undertaken at the Port of Elizabeth proposed to: 1. Catalog the different vegetable and fruit crops entering this country; 2. Evaluate the potential risk to New Jersey crops that an introduced exotic pest might pose; and 3. Evaluate the potential that imported crops entering the U.S. have for harboring exotic pests. The New Jersey IMPORT report, or Invasive Management Promoting Open and Responsible Trade project, details a newly designed ecological risk assessment tool to evaluate entry potential of invasive pests at the Port of Elizabeth. Risk designations were assigned to shipments of four fruits; seven vegetables; and two field/forage crops based on: i) Country of origin; ii) Amounts of commodities imported; and iii) Endemic pests present in exporting countries. Between 5,000 and 180,000 tons of crops were imported into the Port of Elizabeth from October 2001 to 2003. Pest risk analyses were drafted for twenty-five intercepted insects taken from the Port Information Network. In addition, eighteen pest risk analyses were drafted for invasive fungi, bacteria, and viruses of global concern as alerted by ProMed Digest. It was concluded that three crops imported remain at high risk: apples, peppers, and tomatoes. Peaches, soybeans, lettuce, sweet corn, potatoes, squash, and eggplant imported were considered moderate risk. Blueberries, cranberries, and alfalfa were considered low risk.

Generation of Reactive Oxygen Species via NOXa Is Important for Development and Pathogenicity of Mycosphaerella graminicola.

PubMed

Choi, Yoon-E; Lee, Changsu; Goodwin, Stephen B

2016-03-01

The ascomycete fungus Mycosphaerella graminicola (synonym Zymoseptoria tritici) is an important pathogen of wheat causing economically significant losses. The primary nutritional mode of this fungus is thought to be hemibiotrophic. This pathogenic lifestyle is associated with an early biotrophic stage of nutrient uptake followed by a necrotrophic stage aided possibly by production of a toxin or reactive oxygen species (ROS). In many other fungi, the genes CREA and AREA are important during the biotrophic stage of infection, while the NOXa gene product is important during necrotrophic growth. To test the hypothesis that these genes are important for pathogenicity of M. graminicola, we employed an over-expression strategy for the selected target genes CREA, AREA, and NOXa, which might function as regulators of nutrient acquisition or ROS generation. Increased expressions of CREA, AREA, and NOXa in M. graminicola were confirmed via quantitative real-time PCR and strains were subsequently assayed for pathogenicity. Among them, the NOXa over-expression strain, NO2, resulted in significantly increased virulence. Moreover, instead of the usual filamentous growth, we observed a predominance of yeast-like growth of NO2 which was correlated with ROS production. Our data indicate that ROS generation via NOXa is important to pathogenicity as well as development in M. graminicola.

Divergences in hydraulic architecture form an important basis for niche differentiation between diploid and polyploid Betula species in NE China.

PubMed

Zhang, Wei-Wei; Song, Jia; Wang, Miao; Liu, Yan-Yan; Li, Na; Zhang, Yong-Jiang; Holbrook, N Michele; Hao, Guang-You

2017-05-01

Habitat differentiation between polyploid and diploid plants are frequently observed, with polyploids usually occupying more stressed environments. In woody plants, polyploidization can greatly affect wood characteristics but knowledge of its influences on xylem hydraulics is scarce. The four Betula species in NE China, representing two diploids and two polyploids with obvious habitat differentiation, provide an exceptional study system for investigating the impact of polyploidization on environmental adaptation of trees from the point view of xylem hydraulics. To test the hypothesis that changes in hydraulic architecture play an important role in determining their niche differentiation, we measured wood structural traits at both the tissue and pit levels and quantified xylem water transport efficiency and safety in these species. The two polyploids had significantly larger hydraulic weighted mean vessel diameters than the two diploids (45.1 and 45.5 vs 25.9 and 24.5 μm) although the polyploids are occupying more stressed environments. As indicated by more negative water potentials corresponding to 50% loss of stem hydraulic conductivities, the two polyploids exhibited significantly higher resistance to drought-induced embolism than the two diploids (-5.23 and -5.05 vs -3.86 and -3.13 MPa) despite their larger vessel diameters. This seeming discrepancy is reconciled by distinct characteristics favoring greater embolism resistance at the pit level in the two polyploid species. Our results showed clearly that the two polyploid species have remarkably different pit-level anatomical traits favoring greater hydraulic safety than their congeneric diploid species, which have likely contributed to the abundance of polyploid birches in more stressed habitats; however, less porous inter-conduit pits together with a reduced leaf to sapwood area may have compromised their competitiveness under more favorable conditions. Contrasts in hydraulic architecture between diploid and

Cold atmospheric pressure plasma elimination of clinically important single- and mixed-species biofilms.

PubMed

Modic, Martina; McLeod, Neil P; Sutton, J Mark; Walsh, James L

2017-03-01

Mixed-species biofilms reflect the natural environment of many pathogens in clinical settings and are highly resistant to disinfection methods. An indirect cold atmospheric-pressure air-plasma system was evaluated under two different discharge conditions for its ability to kill representative Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) pathogens. Plasma treatment of individual 24-h-old biofilms and mixed-species biofilms that contained additional species (Enterococcus faecalis and Klebsiella pneumoniae) was considered. Under plasma conditions that favoured the production of reactive nitrogen species (RNS), individual P. aeruginosa biofilms containing ca. 5.0 × 10 6 CFU were killed extremely rapidly, with no bacterial survival detected at 15 s of exposure. Staphylococcus aureus survived longer under these conditions, with no detectable growth after 60 s of exposure. In mixed-species biofilms, P. aeruginosa survived longer but all species were killed with no detectable growth at 60 s. Under plasma conditions that favoured the production of reactive oxygen species (ROS), P. aeruginosa showed increased survival, with the lower limit of detection reached by 120 s, and S. aureus was killed in a similar time frame. In the mixed-species model, bacterial kill was biphasic but all pathogens showed viable cells after 240 s of exposure, with P. aeruginosa showing significant survival (ca. 3.6 ± 0.6 × 10 6 CFU). Overall, this study shows the potential of indirect air plasma treatment to achieve significant bacterial kill, but highlights aspects that might affect performance against key pathogens, especially in real-life settings within mixed populations. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

[Seasonal variation of proximate composition in three commercially important species in the Gulf of Nicoya, Puntarenas, Costa Rica].

PubMed

Rodríguez, Cristian Fonseca; Solera, Fabián Chavarriá; Mejía-Arana, Fernando

2013-03-01

Nutritional value of seafood for human consumption is worldwide recognized. Some information have been generated in other countries, nevertheless, there is limited information describing the chemical composition of some fishery important species caught in the Gulf of Nicoya. For this reason, we studied the levels of proximal components of the edible parts (fresh) of three commercially important species. The meat samples of snook Centropomus unionesis, the shrimp Trachypenaeus byrdi and the bivalve Polymesoda radiata, were collected from the Puntarenas local fish market during the fishing season of February 2009 to January 2010. Proximate composition analysis was determined according to AOAC methodology, and evaluated the moisture content, and protein and lipid composition of shellfish meats. The results indicated that the moisture content ranged from 74.6-80.6g/100g for snook 76.9-80.0g/100g for shrimp and 77.9-89.5g/100g for green mussel. After the moisture, the protein was the most abundant chemical fraction (6.8 to 21g/100g) showing the highest values in February for the shrimp and green mussel, and December for snook. The largest fluctuations in the lipid content were found in the snook, ranging from 0.7g/100g to 5.6g/100g; the highest values in this fraction were found in shrimp, green mussel and snook, for July, February and April samples respectively. Considering these results, we concluded that fish and shrimp species studied are a good alternative for human consumption as a source of protein and low lipid content.

Selection for salt tolerance in tidal freshwater swamp species: Advances using baldcypress as a model for restoration: Chapter 14

USGS Publications Warehouse

Krauss, Ken W.; Chambers, Jim L.; Creech, David L.

2007-01-01

Worldwide, the intrusion of salinity into irrigated and natural landscapes has major economic and cultural impacts and has resulted in large reductions in crop yields (Epstein et al. 1980; Flowers 2003). Losses have prompted wide-scale programs to improve the salt tolerance of many agronomic species or to identify crop species that can tolerate lands affected by low levels of salinity. Few historic research efforts have considered forest tree species in the United States, especially in nonurban areas. Newer programs have focused on identifying salt tolerance in forest tree species but have mainly limited these efforts to compiling lists of salt tolerant species to be used in afforestation projects (Gogate et al. 1984; Shrivastava et al. 1988; Beckmann 1991; Bell 1999). Gogate et al. (1984), for instance, listed 26 potential species from Australia with silvicultural application to salt affected lands in India. More comprehensive efforts have considered species lists along with specific site requirements (Bell 1999); species tolerant to saline irrigation waters on dry land, for example, will not often be tolerant of salinity increases in wetland settings. Similar ideas have spawned field trials of native and nonnative tree species in India, Pakistan, Thailand, Australia, and the United States (Thomson 1988; Beckmann 1991; Krauss et al. 2000; Conner and Ozalp 2002; Marcar and Crawford 2004; Conner and Inabinette 2005). Concerted attempts at salt tolerance improvement of forest tree species have been limited, owing in part to the diversity of regional issues that such programs must consider. Whereas food, fodder, and pulp yield may be the major improvement goal on salt affected lands in India (Mathur and Sharma 1984), identifying trees that can survive deicing salts (Townsend 1989), oil and gas brine discharges (Auchmoody and Walters 1988), or sea-level rise induced salinity changes (Pezeshki et al. 1987, 1990) are of greater interest to larger industrial nations

Save Our Species: Protecting Endangered Species from Pesticides.

ERIC Educational Resources Information Center

Environmental Protection Agency, Washington, DC.

This full-size poster profiles 11 wildlife species that are endangered. Color illustrations of animals and plants are accompanied by narrative describing their habitats and reasons for endangerment. The reverse side of the poster contains information on the Endangered Species Act, why protecting endangered and threatened species is important, how…

Evolution of Gene Duplication in Plants.

PubMed

Panchy, Nicholas; Lehti-Shiu, Melissa; Shiu, Shin-Han

2016-08-01

Ancient duplication events and a high rate of retention of extant pairs of duplicate genes have contributed to an abundance of duplicate genes in plant genomes. These duplicates have contributed to the evolution of novel functions, such as the production of floral structures, induction of disease resistance, and adaptation to stress. Additionally, recent whole-genome duplications that have occurred in the lineages of several domesticated crop species, including wheat (Triticum aestivum), cotton (Gossypium hirsutum), and soybean (Glycine max), have contributed to important agronomic traits, such as grain quality, fruit shape, and flowering time. Therefore, understanding the mechanisms and impacts of gene duplication will be important to future studies of plants in general and of agronomically important crops in particular. In this review, we survey the current knowledge about gene duplication, including gene duplication mechanisms, the potential fates of duplicate genes, models explaining duplicate gene retention, the properties that distinguish duplicate from singleton genes, and the evolutionary impact of gene duplication. © 2016 American Society of Plant Biologists. All Rights Reserved.

Use of modern tomato breeding germplasm for deciphering the genetic control of agronomical traits by Genome Wide Association study.

PubMed

Bauchet, Guillaume; Grenier, Stéphane; Samson, Nicolas; Bonnet, Julien; Grivet, Laurent; Causse, Mathilde

2017-05-01

A panel of 300 tomato accessions including breeding materials was built and characterized with >11,000 SNP. A population structure in six subgroups was identified. Strong heterogeneity in linkage disequilibrium and recombination landscape among groups and chromosomes was shown. GWAS identified several associations for fruit weight, earliness and plant growth. Genome-wide association studies (GWAS) have become a method of choice in quantitative trait dissection. First limited to highly polymorphic and outcrossing species, it is now applied in horticultural crops, notably in tomato. Until now GWAS in tomato has been performed on panels of heirloom and wild accessions. Using modern breeding materials would be of direct interest for breeding purpose. To implement GWAS on a large panel of 300 tomato accessions including 168 breeding lines, this study assessed the genetic diversity and linkage disequilibrium decay and revealed the population structure and performed GWA experiment. Genetic diversity and population structure analyses were based on molecular markers (>11,000 SNP) covering the whole genome. Six genetic subgroups were revealed and associated to traits of agronomical interest, such as fruit weight and disease resistance. Estimates of linkage disequilibrium highlighted the heterogeneity of its decay among genetic subgroups. Haplotype definition allowed a fine characterization of the groups and their recombination landscape revealing the patterns of admixture along the genome. Selection footprints showed results in congruence with introgressions. Taken together, all these elements refined our knowledge of the genetic material included in this panel and allowed the identification of several associations for fruit weight, plant growth and earliness, deciphering the genetic architecture of these complex traits and identifying several new loci useful for tomato breeding.

Feeding habits and trophic level of the Panama grunt Pomadasys panamensis, an important bycatch species from the shrimp trawl fishery in the Gulf of California.

PubMed

Rodríguez-Preciado, José A; Amezcua, Felipe; Bellgraph, Brian; Madrid-Vera, Juan

2014-01-01

The Panama grunt is an abundant and commercially important species in the southeastern Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results indicate that the Panama grunt is a benthic predator throughout its life cycle and feeds mainly on infaunal crustaceans. Diet differences among grunt were not found according to size, diet, or season. Shannon diversity index results indicate that Panama grunt has a limited trophic niche breadth with a diet dominated by a limited number of taxa as crustaceans. The estimated trophic level of this species is 3.59. Overall, the Panama grunt is a carnivorous fish occupying the intermediate levels of the trophic pyramid.

Feeding habits and trophic level of the Panama grunt Pomadasys panamensis, an important bycatch species from the shrimp trawl fishery in the Gulf of California

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

Rodriguez-Preciado, Jose A.; Amezcua-Martinez, Felipe; Bellgraph, Brian J.

The Panama grunt is an abundant and commercially important species in the SE Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results show that the Panama grunt is a benthic predator throughout its life cycle and feeds mainly on infaunal crustaceans. Diet differences were not found according to size, diet or season. Shannon diversity index results indicate that Panama grunt have amore » limited trophic niche breadth with a diet dominated by a limited number of taxa. The estimated trophic level of this species is 3.59. Overall, the Panama grunt is a carnivorous fish occupying the intermediate levels of the trophic pyramid.« less

Relative importance of habitat filtering and limiting similarity on species assemblages of alpine and subalpine plant communities.

PubMed

Takahashi, Koichi; Tanaka, Saeka

2016-11-01

This study examined how habitat filtering and limiting similarity affect species assemblages of alpine and subalpine plant communities along a slope gradient on Mt. Norikura in central Japan. Plant traits (plant height, individual leaf area, specific leaf area (SLA), leaf linearity, leaf nitrogen and chlorophyll concentrations) and abiotic environmental factors (elevation, slope inclination, ground surface texture, soil water, soil pH, soil nutrient concentrations of NH 4 -N and NO 3 -N) were examined. The metrics of variance, range, kurtosis and the standard deviation of neighbor distance divided by the range of traits present (SDNDr) were calculated for each plant trait to measure trait distribution patterns. Limiting similarity was detected only for chlorophyll concentration. By contrast, habitat filtering was detected for individual leaf area, SLA, leaf linearity, chlorophyll concentration. Abiotic environmental factors were summarized by the principal component analysis (PCA). The first PCA axis positively correlated with elevation and soil pH, and negatively correlated with sand cover, soil water, NH 4 -N and NO 3 -N concentrations. High values of the first PCA axis represent the wind-exposed upper slope with lower soil moisture and nutrient availabilities. Plant traits changed along the first PCA axis. Leaf area, SLA and chlorophyll concentration decreased, and leaf linearity increased with the first PCA axis. This study showed that the species assemblage of alpine and subalpine plants was determined mainly by habitat filtering, indicating that abiotic environmental factors are more important for species assemblage than interspecific competition. Therefore, only species adapting to abiotic environments can distribute to these environments.

The importance of mercury in leaves, bark and wood of eight tree species across four northeastern forests

NASA Astrophysics Data System (ADS)

Yanai, R. D.; Yang, Y.; Driscoll, C. T.; Montesdeoca, M.

2016-12-01

Mercury (Hg) deposition affects forests even in remote areas, but the amount of Hg in trees is not well known, in part because concentrations of Hg in wood are often below the analytical detection limit by ICP-OES. We analyzed Hg in wood, bark, and foliage of 8 tree species across four sites (Huntington Forest, NY; Sleepers River, VT; Hubbard Brook, NH; Bear Brook, ME) in the northeastern USA, using thermal decomposition, catalytic conversion, amalgamation, and atomic absorption spectrophotometry (USEPA Method 7473). The hardwood species, namely American beech (Fagus grandifolia Ehrh.), white ash (Fraxinus americana L.), yellow birch (Betula alleghaniensis Britt.), sugar maple (Acer saccharum Marshall.), and red maple (Acer rubrum L.), had lower Hg concentrations (averaging 7.7 ng g-1 in bark and 16.3 ng g-1 in foliage) than the conifers, namely red spruce (Picea rubens Sarg.), balsam fir (Abies balsamea (L.) Mill.) and white pine (Pinus strobus L.) (averaging 22.5 ng g-1 in bark and 28.6 ng g-1 in foliage) (p < 0.001). Yellow birch had especially high Hg in wood (2.5 ng g-1) (p < 0.001); the other species averaged 1.4 ng g-1. The Hg content of aboveground biomass, estimated from modeled tree biomass and species composition at each site, declined from the west to the east. Wood is important to Hg budgets in spite of low concentrations, because of its large mass. With the proper analytical methods, it is possible to estimate pools and fluxes of Hg in forest vegetation.

Terrestrial animals as invasive species and as species at risk from invasions

Treesearch

Deborah M. Finch; Dean Pearson; Joseph Wunderle; Wayne Arendt

2010-01-01

Including terrestrial animal species in the invasive species strategy plan is an important step in invasive species management. Invasions by nonindigenous species threaten nearly 50 percent of imperiled native species in the United States and are the Nation's second leading cause of species endangerment. Invasion and conversion of native habitats by exotic species...

Designing an accompanying ecosystem to foster entrepreneurship among agronomic and forestry engineering students. Opinion and commitment of university lecturers

NASA Astrophysics Data System (ADS)

Ortiz-Medina, L.; Fernández-Ahumada, E.; Lara-Vélez, P.; Taguas, E. V.; Gallardo-Cobos, R.; del Campillo, M. C.; Guerrero-Ginel, J. E.

2016-07-01

In the Higher School of Agronomic and Forestry Engineering of the University of Cordoba, a collective project conceived as an 'ecosystem to support and accompany entrepreneurs' has been proposed. The approach aims to spread and consolidate the entrepreneurial spirit and to respond to the demands of possible stakeholders involved in the whole process of training, as well as the subsequent integration of graduates into the labour market. Putting into practice this initiative, which involves multiple actors, is a complex and difficult task. For this reason, prior to its implementation, the authors considered it necessary to listen to main stakeholders' opinions and evaluate their degree of commitment and the requirements they consider important for the viability and sustainability of the initiative. This paper focuses on the faculty's opinions, gathered by means of a survey conducted with the entire faculty (N = 128, response rate = 45%) and semi-structured interviews held with 20 members of the School board. The results suggest that there is a general consensus on the suitability of this collective project and that there is a core of teachers willing to get involved. Evidently, guidelines need to be produced to facilitate taking on such tasks. However, the main drawbacks are related with the conflict between formal requirements of professor professional profile and the steps needed to establish the ecosystem.

Quantitative analysis of desorption and decomposition kinetics of formic acid on Cu(111): The importance of hydrogen bonding between adsorbed species

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

Shiozawa, Yuichiro; Koitaya, Takanori; Mukai, Kozo

2015-12-21

Quantitative analysis of desorption and decomposition kinetics of formic acid (HCOOH) on Cu(111) was performed by temperature programmed desorption (TPD), X-ray photoelectron spectroscopy, and time-resolved infrared reflection absorption spectroscopy. The activation energy for desorption is estimated to be 53–75 kJ/mol by the threshold TPD method as a function of coverage. Vibrational spectra of the first layer HCOOH at 155.3 K show that adsorbed molecules form a polymeric structure via the hydrogen bonding network. Adsorbed HCOOH molecules are dissociated gradually into monodentate formate species. The activation energy for the dissociation into monodentate formate species is estimated to be 65.0 kJ/mol atmore » a submonolayer coverage (0.26 molecules/surface Cu atom). The hydrogen bonding between adsorbed HCOOH species plays an important role in the stabilization of HCOOH on Cu(111). The monodentate formate species are stabilized at higher coverages, because of the lack of vacant sites for the bidentate formation.« less

Ultrastructure analysis of the immature stages of Ravinia belforti (Diptera: Sarcophagidae), a species of medical-veterinary and forensic importance, by scanning electron microscopy.

PubMed

da-Silva-Xavier, Alexandre; de Carvalho Queiroz, Margareth Maria

2016-07-01

The postmortem interval is related to the age of immature species of flies found on corpses and can be estimated using data available in the literature on the biology of the species. The flesh fly Ravinia belforti is a carrier of enteric pathogens that can affect human and animal health as well as being of forensic importance. As the morphology of many immature Sarcophagidae is unknown, these immature forms must be collected and characterized after the emergence of the adult male. Here we describe and analyze the morphological characteristics of the larvae stages L1, L2, L3 and the puparium of R. belforti by scanning electron microscopy (SEM). Ten specimens of each stage were analyzed. Larvae of R. belforti follow the typical muscoid vermiform pattern with 12 segments. The anterior region is pointed, while the posterior region is thicker. The spines of the cephalic collar are flattened and with double, triple or quadruple points, different from the spines along the body that only have a single point. In L2, the anterior spiracle is present with a varying number of papillae (16-22), differing from other species. The posterior spiracles are located within the peritreme. The spiracular cavity is internalized in the posterior region, following the pattern that differs Sarcophagidae from other families. L3 features more visible and developed spines around the cephalic collar, getting thicker and denser near to the first thoracic segment. Puparium is similar to other species of Sarcophagidae. This paper presents important data on this family which has both health and forensic importance. Furthermore, R. belforti shows significant differences from other species of Sarcophagidae. Copyright © 2016 Elsevier B.V. All rights reserved.

Agronomic Characteristics Related to Grain Yield and Nutrient Use Efficiency for Wheat Production in China

PubMed Central

Zheng, Huaiguo; Xu, Xinpeng

2016-01-01

In order to make clear the recent status and trend of wheat (Triticum aestivum L.) production in China, datasets from multiple field experiments and published literature were collected to study the agronomic characteristics related to grain yield, fertilizer application and nutrient use efficiency from the year 2000 to 2011. The results showed that the mean grain yield of wheat in 2000–2011 was 5950 kg/ha, while the N, P2O5 and K2O application rates were 172, 102 and 91 kg/ha on average, respectively. The decrease in N and P2O5 and increase in K2O balanced the nutrient supply and was the main reason for yield increase. The partial factor productivity (PFP, kg grain yield produced per unit of N, P2O5 or K2O applied) values of N (PFP-N), P (PFP-P) and K (PFP-K) were in the ranges of 29.5~39.6, 43.4~74.9 and 44.1~76.5 kg/kg, respectively. While PFP-N showed no significant changes from 2000 to 2010, both PFP-P and PFP-K showed an increased trend over this period. The mean agronomic efficiency (AE, kg grain yield increased per unit of N, P2O5 or K2O applied) values of N (AEN), P (AEP) and K (AEK) were 9.4, 10.2 and 6.5 kg/kg, respectively. The AE values demonstrated marked inter-annual fluctuations, with the amplitude of fluctuation for AEN greater than those for AEP and AEK. The mean fertilizer recovery efficiency (RE, the fraction of nutrient uptake in aboveground plant dry matter to the nutrient of fertilizer application) values of N, P and K in the aboveground biomass were 33.1%, 24.3% and 28.4%, respectively. It was also revealed that different wheat ecological regions differ greatly in wheat productivity, fertilizer application and nutrient use efficiency. In summary, it was suggested that best nutrient management practices, i.e. fertilizer recommendation applied based on soil testing or yield response, with strategies to match the nutrient input with realistic yield and demand, or provided with the 4R’s nutrient management (right time, right rate, right site

Relative importance of bird species as hosts for immature Ixodes dammini (Acari: Ixodidae) in a suburban residential landscape of southern New York State.

PubMed

Battaly, G R; Fish, D

1993-07-01

Abundance of birds and their tick parasites were estimated in a residential community located in Westchester County, NY, where Lyme disease is endemic. In total, 36 bird species (416 captures) were collected, of which 25 species (69%) were parasitized by ticks. Ixodes dammini Spielman, Clifford, Piesman & Corwin composed 96.4% of the 1,067 ticks found on birds. The bird species most heavily parasitized was house wren, Troglodytes aedon Vieillot (11.1 Ixodes dammini per bird). Relative density estimates of birds, using fixed circle radius counts, revealed dominance by the American robin, Turdus migratorius L. (29.3%), followed by the common grackle, Quiscalus quiscula (L.) (9.3%). Bird density estimates were combined with tick abundance data to calculate an importance value for each bird species as a host for immature I. dammini. The American robin was most important, accounting for 72.7% of all larval I dammini found on birds, followed by the common grackle (8.2%) and the house wren (5.9%). Both the American robin and house wren are reservoir competent for the Lyme disease spirochete Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner and therefore may contribute to the risk of Lyme disease for humans. During August when larvae were most prevalent, 39% of the American robins and 70% of the common grackles were observed on lawns. These species are probable contributors to nymphal I. dammini populations found on lawns.

Effect of bait decomposition on the attractiveness to species of Diptera of veterinary and forensic importance in a rainforest fragment in Brazil.

PubMed

Oliveira, Diego L; Soares, Thiago F; Vasconcelos, Simão D

2016-01-01

Insects associated with carrion can have parasitological importance as vectors of several pathogens and causal agents of myiasis to men and to domestic and wild animals. We tested the attractiveness of animal baits (chicken liver) at different stages of decomposition to necrophagous species of Diptera (Calliphoridae, Fanniidae, Muscidae, Phoridae and Sarcophagidae) in a rainforest fragment in Brazil. Five types of bait were used: fresh and decomposed at room temperature (26 °C) for 24, 48, 72 and 96 h. A positive correlation was detected between the time of decomposition and the abundance of Calliphoridae and Muscidae, whilst the abundance of adults of Phoridae decreased with the time of decomposition. Ten species of calliphorids were registered, of which Chrysomya albiceps, Chrysomya megacephala and Chloroprocta idioidea showed a positive significant correlation between abundance and decomposition. Specimens of Sarcophagidae and Fanniidae did not discriminate between fresh and highly decomposed baits. A strong female bias was registered for all species of Calliphoridae irrespective of the type of bait. The results reinforce the feasibility of using animal tissues as attractants to a wide diversity of dipterans of medical, parasitological and forensic importance in short-term surveys, especially using baits at intermediate stages of decomposition.

Analysis of genomic rearrangements, horizontal gene transfer and role of plasmids in the evolution of industrial important Thermus species.

PubMed

Kumwenda, Benjamin; Litthauer, Derek; Reva, Oleg

2014-09-25

Bacteria of genus Thermus inhabit both man-made and natural thermal environments. Several Thermus species have shown biotechnological potential such as reduction of heavy metals which is essential for eradication of heavy metal pollution; removing of organic contaminants in water; opening clogged pipes, controlling global warming among many others. Enzymes from thermophilic bacteria have exhibited higher activity and stability than synthetic or enzymes from mesophilic organisms. Using Meiothermus silvanus DSM 9946 as a reference genome, high level of coordinated rearrangements has been observed in extremely thermophilic Thermus that may imply existence of yet unknown evolutionary forces controlling adaptive re-organization of whole genomes of thermo-extremophiles. However, no remarkable differences were observed across species on distribution of functionally related genes on the chromosome suggesting constraints imposed by metabolic networks. The metabolic network exhibit evolutionary pressures similar to levels of rearrangements as measured by the cross-clustering index. Using stratigraphic analysis of donor-recipient, intensive gene exchanges were observed from Meiothermus species and some unknown sources to Thermus species confirming a well established DNA uptake mechanism as previously proposed. Global genome rearrangements were found to play an important role in the evolution of Thermus bacteria at both genomic and metabolic network levels. Relatively higher level of rearrangements was observed in extremely thermophilic Thermus strains in comparison to the thermo-tolerant Thermus scotoductus. Rearrangements did not significantly disrupt operons and functionally related genes. Thermus species appeared to have a developed capability for acquiring DNA through horizontal gene transfer as shown by the donor-recipient stratigraphic analysis.

Evaluation of Borage Extracts As Potential Biostimulant Using a Phenomic, Agronomic, Physiological, and Biochemical Approach.

PubMed

Bulgari, Roberta; Morgutti, Silvia; Cocetta, Giacomo; Negrini, Noemi; Farris, Stefano; Calcante, Aldo; Spinardi, Anna; Ferrari, Enrico; Mignani, Ilaria; Oberti, Roberto; Ferrante, Antonio

2017-01-01

Biostimulants are substances able to improve water and nutrient use efficiency and counteract stress factors by enhancing primary and secondary metabolism. Premise of the work was to exploit raw extracts from leaves (LE) or flowers (FE) of Borago officinalis L., to enhance yield and quality of Lactuca sativa 'Longifolia,' and to set up a protocol to assess their effects. To this aim, an integrated study on agronomic, physiological and biochemical aspects, including also a phenomic approach, has been adopted. Extracts were diluted to 1 or 10 mL L -1 , sprayed onto lettuce plants at the middle of the growing cycle and 1 day before harvest. Control plants were treated with water. Non-destructive analyses were conducted to assess the effect of extracts on biomass with an innovative imaging technique, and on leaf photosynthetic efficiency (chlorophyll a fluorescence and leaf gas exchanges). At harvest, the levels of ethylene, photosynthetic pigments, nitrate, and primary (sucrose and total sugars) and secondary (total phenols and flavonoids) metabolites, including the activity and levels of phenylalanine ammonia lyase (PAL) were assessed. Moreover, a preliminary study of the effects during postharvest was performed. Borage extracts enhanced the primary metabolism by increasing leaf pigments and photosynthetic activity. Plant fresh weight increased upon treatments with 10 mL L -1 doses, as correctly estimated by multi-view angles images. Chlorophyll a fluorescence data showed that FEs were able to increase the number of active reaction centers per cross section; a similar trend was observed for the performance index. Ethylene was three-fold lower in FEs treatments. Nitrate and sugar levels did not change in response to the different treatments. Total flavonoids and phenols, as well as the total protein levels, the in vitro PAL specific activity, and the levels of PAL-like polypeptides were increased by all borage extracts, with particular regard to FEs. FEs also proved

Evaluation of Borage Extracts As Potential Biostimulant Using a Phenomic, Agronomic, Physiological, and Biochemical Approach

PubMed Central

Bulgari, Roberta; Morgutti, Silvia; Cocetta, Giacomo; Negrini, Noemi; Farris, Stefano; Calcante, Aldo; Spinardi, Anna; Ferrari, Enrico; Mignani, Ilaria; Oberti, Roberto; Ferrante, Antonio

2017-01-01

Biostimulants are substances able to improve water and nutrient use efficiency and counteract stress factors by enhancing primary and secondary metabolism. Premise of the work was to exploit raw extracts from leaves (LE) or flowers (FE) of Borago officinalis L., to enhance yield and quality of Lactuca sativa ‘Longifolia,’ and to set up a protocol to assess their effects. To this aim, an integrated study on agronomic, physiological and biochemical aspects, including also a phenomic approach, has been adopted. Extracts were diluted to 1 or 10 mL L–1, sprayed onto lettuce plants at the middle of the growing cycle and 1 day before harvest. Control plants were treated with water. Non-destructive analyses were conducted to assess the effect of extracts on biomass with an innovative imaging technique, and on leaf photosynthetic efficiency (chlorophyll a fluorescence and leaf gas exchanges). At harvest, the levels of ethylene, photosynthetic pigments, nitrate, and primary (sucrose and total sugars) and secondary (total phenols and flavonoids) metabolites, including the activity and levels of phenylalanine ammonia lyase (PAL) were assessed. Moreover, a preliminary study of the effects during postharvest was performed. Borage extracts enhanced the primary metabolism by increasing leaf pigments and photosynthetic activity. Plant fresh weight increased upon treatments with 10 mL L–1 doses, as correctly estimated by multi-view angles images. Chlorophyll a fluorescence data showed that FEs were able to increase the number of active reaction centers per cross section; a similar trend was observed for the performance index. Ethylene was three-fold lower in FEs treatments. Nitrate and sugar levels did not change in response to the different treatments. Total flavonoids and phenols, as well as the total protein levels, the in vitro PAL specific activity, and the levels of PAL-like polypeptides were increased by all borage extracts, with particular regard to FEs. FEs also

Agronomic and environmental consequences of using liquid mineral concentrates on arable farms.

PubMed

Schils, René L M; Postma, Romke; van Rotterdam, Debby; Zwart, Kor B

2015-12-01

In regions with intensive livestock systems, the processing of manure into liquid mineral concentrates is seen as an option to increase the nutrient use efficiency of manures. The agricultural sector anticipates that these products may in future be regarded as regular mineral fertilisers. We assessed the agronomic suitability and impact on greenhouse gas (GHG) and ammonia emissions of using liquid mineral concentrates on arable farms. The phosphate requirements on arable farms were largely met by raw pig slurry, given its large regional availability. After the initial nutrient input by means of pig slurry, the nitrogen/phosphate ratio of the remaining nutrient crop requirements determined the additional amount of liquid mineral concentrates that can be used. For sandy soils, liquid mineral concentrates could supply 50% of the nitrogen requirement, whereas for clay soils the concentrates did not meet the required nitrogen/phosphate ratio. The total GHG emissions per kg of plant available nitrogen ranged from -65 to 33 kg CO2 -equivalents. It increased in the order digestates < mineral fertiliser < raw slurries. Liquid mineral concentrates had limited added value for arable farms. For an increased suitability it is necessary that liquid mineral concentrates do not contain phosphate and that the nitrogen availability is increased. In the manure-processing chain, anaerobic digestion had a dominant and beneficial effect on GHG emissions. © 2015 Society of Chemical Industry.

Accumulation patterns of lipophilic organic contaminants in surface sediments and in economic important mussel and fish species from Jakarta Bay, Indonesia.

PubMed

Dwiyitno; Dsikowitzky, Larissa; Nordhaus, Inga; Andarwulan, Nuri; Irianto, Hari Eko; Lioe, Hanifah Nuryani; Ariyani, Farida; Kleinertz, Sonja; Schwarzbauer, Jan

2016-09-30

Non-target screening analyses were conducted in order to identify a wide range of organic contaminants in sediment and animal tissue samples from Jakarta Bay. High concentrations of di-iso-propylnaphthalenes (DIPNs), linear alkylbenzenes (LABs) and polycyclic aromatic hydrocarbons (PAHs) were detected in all samples, whereas phenylmethoxynaphthalene (PMN), DDT and DDT metabolites (DDX) were detected at lower concentrations. In order to evaluate the uptake and accumulation by economic important mussel (Perna viridis) and fish species, contaminant patterns of DIPNs, LABs and PAHs in different compartments were compared. Different patterns of these contaminant groups were found in sediment and animal tissue samples, suggesting compound-specific accumulation and metabolism processes. Significantly higher concentrations of these three contaminant groups in mussel tissue as compared to fish tissue from Jakarta Bay were found. Because P. viridis is an important aquaculture species in Asia, this result is relevant for food safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic control and combining ability of agronomic attributes and northern leaf blight-related attributes in popcorn.

PubMed

Santos, J S; Amaral Júnior, A T; Vivas, M; Mafra, G S; Pena, G F; Silva, F H L; Guimarães, A G

2017-09-27

The present study was conducted to investigate the genetic control and to estimate the general and specific combining abilities of popcorn for agronomic attributes and attributes related to resistance to northern leaf blight (NLB). The 56 hybrids (F 1 and reciprocals), together with the eight parent lines and six controls, were evaluated in two harvests, in a randomized-block design with four replications. Dominance components were more expressive than the additive components for grain yield and expression of resistance, and hybridization was the most suitable option for obtaining resistant and productive genotypes. For grain yield, popping expansion, and resistance to NLB, there was no significance for reciprocal effects, which indicates that the direction in which the cross is performed does not interfere with the hybrid's performance. Then, the superior hybrids recommended for more profitable growth were P8 x L61, L61 x L76, and L61 x L77.

Long-term field phytoextraction of zinc/cadmium contaminated soil by Sedum plumbizincicola under different agronomic strategies.

PubMed

Deng, Lin; Li, Zhu; Wang, Jie; Liu, Hongyan; Li, Na; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Christie, Peter

2016-01-01

In two long-term field experiments the zinc (Zn)/cadmium (Cd) hyperaccumulator Sedum plumbizincicola (S. plumbizincicola) was examined to optimize the phytoextraction of metal contaminated soil by two agronomic strategies of intercropping with maize (Zea mays) and plant densities. Soil total Zn and Cd concentrations decreased markedly after long-term phytoextraction. But shoot biomass and Cd and Zn concentrations showed no significant difference with increasing remediation time. In the intercropping experiment the phytoremediation efficiency in the treatment "S. plumbizincicola intercropped with maize" was higher than in S. plumbizincicola monocropping, and Cd concentrations of corn were below the maximum national limit. In the plant density experiment the phytoremediation efficiency increased with increasing plant density and 440,000 plants ha(-1) gave the maximum rate. These results indicated that S. plumbizincicola at an appropriate planting density and intercropped with maize can achieve high remediation efficiency to contaminated soil without affecting the cereal crop productivity. This cropping system combines adequate agricultural production with soil heavy metal phytoextraction.

Haplotype analysis of sucrose synthase gene family in three Saccharum species

PubMed Central

2013-01-01

Background Sugarcane is an economically important crop contributing about 80% and 40% to the world sugar and ethanol production, respectively. The complicated genetics consequential to its complex polyploid genome, however, have impeded efforts to improve sugar yield and related important agronomic traits. Modern sugarcane cultivars are complex hybrids derived mainly from crosses among its progenitor species, S. officinarum and S. spontanuem, and to a lesser degree, S. robustom. Atypical of higher plants, sugarcane stores its photoassimilates as sucrose rather than as starch in its parenchymous stalk cells. In the sugar biosynthesis pathway, sucrose synthase (SuSy, UDP-glucose: D-fructose 2-a-D-glucosyltransferase, EC 2.4.1.13) is a key enzyme in the regulation of sucrose accumulation and partitioning by catalyzing the reversible conversion of sucrose and UDP into UDP-glucose and fructose. However, little is known about the sugarcane SuSy gene family members and hence no definitive studies have been reported regarding allelic diversity of SuSy gene families in Saccharum species. Results We identified and characterized a total of five sucrose synthase genes in the three sugarcane progenitor species through gene annotation and PCR haplotype analysis by analyzing 70 to 119 PCR fragments amplified from intron-containing target regions. We detected all but one (i.e. ScSuSy5) of ScSuSy transcripts in five tissue types of three Saccharum species. The average SNP frequency was one SNP per 108 bp, 81 bp, and 72 bp in S. officinarum, S. robustom, and S. spontanuem respectively. The average shared SNP is 15 between S. officinarum and S. robustom, 7 between S. officinarum and S. spontanuem , and 11 between S. robustom and S. spontanuem. We identified 27, 35, and 32 haplotypes from the five ScSuSy genes in S. officinarum, S. robustom, and S. spontanuem respectively. Also, 12, 11, and 9 protein sequences were translated from the haplotypes in S. officinarum, S. robustom, S

Haplotype analysis of sucrose synthase gene family in three Saccharum species.

PubMed

Zhang, Jisen; Arro, Jie; Chen, Youqiang; Ming, Ray

2013-05-10

Sugarcane is an economically important crop contributing about 80% and 40% to the world sugar and ethanol production, respectively. The complicated genetics consequential to its complex polyploid genome, however, have impeded efforts to improve sugar yield and related important agronomic traits. Modern sugarcane cultivars are complex hybrids derived mainly from crosses among its progenitor species, S. officinarum and S. spontanuem, and to a lesser degree, S. robustom. Atypical of higher plants, sugarcane stores its photoassimilates as sucrose rather than as starch in its parenchymous stalk cells. In the sugar biosynthesis pathway, sucrose synthase (SuSy, UDP-glucose: D-fructose 2-a-D-glucosyltransferase, EC 2.4.1.13) is a key enzyme in the regulation of sucrose accumulation and partitioning by catalyzing the reversible conversion of sucrose and UDP into UDP-glucose and fructose. However, little is known about the sugarcane SuSy gene family members and hence no definitive studies have been reported regarding allelic diversity of SuSy gene families in Saccharum species. We identified and characterized a total of five sucrose synthase genes in the three sugarcane progenitor species through gene annotation and PCR haplotype analysis by analyzing 70 to 119 PCR fragments amplified from intron-containing target regions. We detected all but one (i.e. ScSuSy5) of ScSuSy transcripts in five tissue types of three Saccharum species. The average SNP frequency was one SNP per 108 bp, 81 bp, and 72 bp in S. officinarum, S. robustom, and S. spontanuem respectively. The average shared SNP is 15 between S. officinarum and S. robustom, 7 between S. officinarum and S. spontanuem , and 11 between S. robustom and S. spontanuem. We identified 27, 35, and 32 haplotypes from the five ScSuSy genes in S. officinarum, S. robustom, and S. spontanuem respectively. Also, 12, 11, and 9 protein sequences were translated from the haplotypes in S. officinarum, S. robustom, S. spontanuem

Assessing the importance of four sandfly species (Diptera: Psychodidae) as vectors of Leishmania mexicana in Campeche, Mexico.

PubMed

Pech-May, A; Peraza-Herrera, G; Moo-Llanes, D A; Escobedo-Ortegón, J; Berzunza-Cruz, M; Becker-Fauser, I; Montes DE Oca-Aguilar, A C; Rebollar-Téllez, E A

2016-09-01

Localized cutaneous leishmaniasis represents a public health problem in many areas of Mexico, especially in the Yucatan Peninsula. An understanding of vector ecology and bionomics is of great importance in evaluations of the transmission dynamics of Leishmania parasites. A field study was conducted in the county of Calakmul, state of Campeche, during the period from November 2006 to March 2007. Phlebotomine sandfly vectors were sampled using Centers for Disease Control light traps, baited Disney traps and Shannon traps. A total of 3374 specimens were captured in the two villages of Once de Mayo (93.8%) and Arroyo Negro (6.1%). In Once de Mayo, the most abundant species were Psathyromyia shannoni, Lutzomyia cruciata, Bichromomyia olmeca olmeca and Psychodopygus panamensis (all: Diptera: Psychodidae). The Shannon trap was by far the most efficient method of collection. The infection rate, as determined by Leishmania mexicana-specific polymerase chain reaction, was 0.3% in Once de Mayo and infected sandflies included Psy. panamensis, B. o. olmeca and Psa. shannoni. There were significant differences in human biting rates across sandfly species and month of sampling. Ecological niche modelling analyses showed an overall overlap of 39.1% for the four species in the whole state of Campeche. In addition, the finding of nine vector-reservoir pairs indicates a potential interaction. The roles of the various sandfly vectors in Calakmul are discussed. © 2016 The Royal Entomological Society.

Row Ratios of Intercropping Maize and Soybean Can Affect Agronomic Efficiency of the System and Subsequent Wheat

PubMed Central

Zhang, Yitao; Liu, Jian; Zhang, Jizong; Liu, Hongbin; Liu, Shen; Zhai, Limei; Wang, Hongyuan; Lei, Qiuliang; Ren, Tianzhi; Yin, Changbin

2015-01-01

Intercropping is regarded as an important agricultural practice to improve crop production and environmental quality in the regions with intensive agricultural production, e.g., northern China. To optimize agronomic advantage of maize (Zea mays L.) and soybean (Glycine max L.) intercropping system compared to monoculture of maize, two sequential experiments were conducted. Experiment 1 was to screening the optimal cropping system in summer that had the highest yields and economic benefits, and Experiment 2 was to identify the optimum row ratio of the intercrops selected from Experiment 1. Results of Experiment 1 showed that maize intercropping with soybean (maize || soybean) was the optimal cropping system in summer. Compared to conventional monoculture of maize, maize || soybean had significant advantage in yield, economy, land utilization ratio and reducing soil nitrate nitrogen (N) accumulation, as well as better residual effect on the subsequent wheat (Triticum aestivum L.) crop. Experiment 2 showed that intercropping systems reduced use of N fertilizer per unit land area and increased relative biomass of intercropped maize, due to promoted photosynthetic efficiency of border rows and N utilization during symbiotic period. Intercropping advantage began to emerge at tasseling stage after N topdressing for maize. Among all treatments with different row ratios, alternating four maize rows with six soybean rows (4M:6S) had the largest land equivalent ratio (1.30), total N accumulation in crops (258 kg ha-1), and economic benefit (3,408 USD ha-1). Compared to maize monoculture, 4M:6S had significantly lower nitrate-N accumulation in soil both after harvest of maize and after harvest of the subsequent wheat, but it did not decrease yield of wheat. The most important advantage of 4M:6S was to increase biomass of intercropped maize and soybean, which further led to the increase of total N accumulation by crops as well as economic benefit. In conclusion, alternating

Agronomic and remedial benefits and risks of applying biochar to soil: Current knowledge and future research directions.

PubMed

Kuppusamy, Saranya; Thavamani, Palanisami; Megharaj, Mallavarapu; Venkateswarlu, Kadiyala; Naidu, Ravi

2016-02-01

'Biochar' represents an emerging technology that is increasingly being recognized for its potential role in carbon sequestration, reducing greenhouse gas emissions, waste management, renewable energy, soil improvement, crop productivity enhancement and environmental remediation. Published reviews have so far focused mainly on the above listed agronomic and environmental benefits of applying biochar, yet paid little or no attention to its harmful effects on the ecological system. This review highlights a balanced overview of the advantages and disadvantages of the pyrolysis process of biochar production, end-product quality and the benefits versus drawbacks of biochar on: (a) soil geochemistry and albedo, (b) microflora and fauna, (c) agrochemicals, (d) greenhouse gas efflux, (e) nutrients, (f) crop yield, and (g) contaminants (organic and inorganic). Future research should focus more on the unintended long-term consequences of biochar on biological organisms and their processes in the soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

Proximate and fatty acid composition of some commercially important fish species from the Sinop region of the Black Sea.

PubMed

Kocatepe, Demet; Turan, Hülya

2012-06-01

The proximate and fatty acid compositions of the commercially important fish species (Engraulis encrasicolus, Alosa alosa, Belone belone, Scorpaena porcus, Pomatomus saltatrix, Mullus barbatus) from the Sinop region of the Black Sea were examined. The fat contents ranged from 1.26% (for scorpion fish) to 18.12% (for shad). The protein contents were min 14.54% (for red mullet) and maximum 20.26% (for belone). The fatty acid compositions of the fish ranged from 27.83 to 35.91% for saturated fatty acids, 19.50-33.80% for monounsaturated fatty acids and 15.25-40.02% for polyunsaturated fatty acids. Among the saturated fatty acids, palmitic acid (16:0) (17.75-22.20%) was the dominant fatty acid for all the fish species. As a second saturated fatty acid, myristic acid (14:0) was observed in four of the fish species and its content ranged from 4.72 to 7.31%. Whereas, for the other two fish species, the second saturated fatty acid was stearic acid (18:0) ranging between 4.54 and 10.64%. Among the monounsaturated fatty acids, those occurring in the highest proportions were oleic acid (18:1n-9c) (11.67-22.45%) and palmitoleic acid (16:1) (4.50-9.40%). Docosahexaenoic acid (22:6n-3) (5.41-28.52%), eicosapentaenoic acid (20:5n-3) (4.68-11.06) and linoleic acid (18:2n-6) (1.38-3.49%) were dominant polyunsaturated fatty acids, respectively. All the species, in particular the belone, the anchovy and the shad had high levels of the n-3 series.

Gaeolaelaps Invictianus, a new and unusual species of Hypoaspidine Mite (Acari: Mesostigmata: Laelapidae) phoretic on the red imported fire ant Solenopsis Invicta Buren (Hymenoptera: Formicidae) in Louisiana, USA

Treesearch

David Walter; John Moser

2010-01-01

A new species ofhypoaspidine laelapid mite, Gaeolaelaps invictianus, associated with the red imported fire ant Solenopsis invicta Buren in the southern United States of America is described. This new species is unusual among the gamasine Mesostigmata in lacking a postanal seta in adults of both sexes and among species of Gaeolaelaps in being phoretic on dispersing male...

50 CFR 222.205 - Import and export requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Certificates of Exemption for Pre-Act Endangered Species Parts § 222.205 Import and export requirements. (a... neither endangered nor threatened species and that are imported for purposes of human or animal...

50 CFR 222.205 - Import and export requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Certificates of Exemption for Pre-Act Endangered Species Parts § 222.205 Import and export requirements. (a... neither endangered nor threatened species and that are imported for purposes of human or animal...

50 CFR 222.205 - Import and export requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Certificates of Exemption for Pre-Act Endangered Species Parts § 222.205 Import and export requirements. (a... neither endangered nor threatened species and that are imported for purposes of human or animal...

50 CFR 222.205 - Import and export requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE SPECIES Certificates of Exemption for Pre-Act Endangered Species Parts § 222.205 Import and export requirements. (a... neither endangered nor threatened species and that are imported for purposes of human or animal...

Nutritional Requirements and Their Importance for Virulence of Pathogenic Cryptococcus Species

PubMed Central

Watkins, Rhys A.; Johnston, Simon A.

2017-01-01

Cryptococcus sp. are basidiomycete yeasts which can be found widely, free-living in the environment. Interactions with natural predators, such as amoebae in the soil, are thought to have promoted the development of adaptations enabling the organism to survive inside human macrophages. Infection with Cryptococcus in humans occurs following inhalation of desiccated yeast cells or spore particles and may result in fatal meningoencephalitis. Human disease is caused almost exclusively by the Cryptococcus neoformans species complex, which predominantly infects immunocompromised patients, and the Cryptococcus gattii species complex, which is capable of infecting immunocompetent individuals. The nutritional requirements of Cryptococcus are critical for its virulence in animals. Cryptococcus has evolved a broad range of nutrient acquisition strategies, many if not most of which also appear to contribute to its virulence, enabling infection of animal hosts. In this review, we summarise the current understanding of nutritional requirements and acquisition in Cryptococcus and offer perspectives to its evolution as a significant pathogen of humans. PMID:28974017

Collection and evaluation of wild perennial Helianthus pumilus achenes for oil concentration and fatty acid composition

USDA-ARS?s Scientific Manuscript database

The genus Helianthus consists of 51 species and 19 subspecies with 14 annual and 37 perennial species. The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from the wild species, which have provided a continued source of desirable agronomic traits. There has ...

Collection and evaluation of wild perennial Helianthus pumilus achenes for oil concentration and fatty acid composition

USDA-ARS?s Scientific Manuscript database

The genus Helianthus consists of 52 species and 19 subspecies with 14 annual and 38 perennial species. The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from the wild species, which have provided a continued source of desirable agronomic traits. There has ...

RNA-Seq Analysis of Cocos nucifera: Transcriptome Sequencing and De Novo Assembly for Subsequent Functional Genomics Approaches

PubMed Central

Xia, Wei; Mason, Annaliese S.; Xia, Zhihui; Qiao, Fei; Zhao, Songlin; Tang, Haoru

2013-01-01

Background Cocos nucifera (coconut), a member of the Arecaceae family, is an economically important woody palm grown in tropical regions. Despite its agronomic importance, previous germplasm assessment studies have relied solely on morphological and agronomical traits. Molecular biology techniques have been scarcely used in assessment of genetic resources and for improvement of important agronomic and quality traits in Cocos nucifera, mostly due to the absence of available sequence information. Methodology/Principal Findings To provide basic information for molecular breeding and further molecular biological analysis in Cocos nucifera, we applied RNA-seq technology and de novo assembly to gain a global overview of the Cocos nucifera transcriptome from mixed tissue samples. Using Illumina sequencing, we obtained 54.9 million short reads and conducted de novo assembly to obtain 57,304 unigenes with an average length of 752 base pairs. Sequence comparison between assembled unigenes and released cDNA sequences of Cocos nucifera and Elaeis guineensis indicated that the assembled sequences were of high quality. Approximately 99.9% of unigenes were novel compared to the released coconut EST sequences. Using BLASTX, 68.2% of unigenes were successfully annotated based on the Genbank non-redundant (Nr) protein database. The annotated unigenes were then further classified using the Gene Ontology (GO), Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Conclusions/Significance Our study provides a large quantity of novel genetic information for Cocos nucifera. This information will act as a valuable resource for further molecular genetic studies and breeding in coconut, as well as for isolation and characterization of functional genes involved in different biochemical pathways in this important tropical crop species. PMID:23555859

RNA-Seq analysis of Cocos nucifera: transcriptome sequencing and de novo assembly for subsequent functional genomics approaches.

PubMed

Fan, Haikuo; Xiao, Yong; Yang, Yaodong; Xia, Wei; Mason, Annaliese S; Xia, Zhihui; Qiao, Fei; Zhao, Songlin; Tang, Haoru

2013-01-01

Cocos nucifera (coconut), a member of the Arecaceae family, is an economically important woody palm grown in tropical regions. Despite its agronomic importance, previous germplasm assessment studies have relied solely on morphological and agronomical traits. Molecular biology techniques have been scarcely used in assessment of genetic resources and for improvement of important agronomic and quality traits in Cocos nucifera, mostly due to the absence of available sequence information. To provide basic information for molecular breeding and further molecular biological analysis in Cocos nucifera, we applied RNA-seq technology and de novo assembly to gain a global overview of the Cocos nucifera transcriptome from mixed tissue samples. Using Illumina sequencing, we obtained 54.9 million short reads and conducted de novo assembly to obtain 57,304 unigenes with an average length of 752 base pairs. Sequence comparison between assembled unigenes and released cDNA sequences of Cocos nucifera and Elaeis guineensis indicated that the assembled sequences were of high quality. Approximately 99.9% of unigenes were novel compared to the released coconut EST sequences. Using BLASTX, 68.2% of unigenes were successfully annotated based on the Genbank non-redundant (Nr) protein database. The annotated unigenes were then further classified using the Gene Ontology (GO), Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Our study provides a large quantity of novel genetic information for Cocos nucifera. This information will act as a valuable resource for further molecular genetic studies and breeding in coconut, as well as for isolation and characterization of functional genes involved in different biochemical pathways in this important tropical crop species.

Nordic-Baltic Student Teachers' Identification of and Interest in Plant and Animal Species: The Importance of Species Identification and Biodiversity for Sustainable Development

ERIC Educational Resources Information Center

Palmberg, Irmeli; Berg, Ida; Jeronen, Eila; Kärkkäinen, Sirpa; Norrgård-Sillanpää, Pia; Persson, Christel; Vilkonis, Rytis; Yli-Panula, Eija

2015-01-01

Knowledge of species, interest in nature, and nature experiences are the factors that best promote interest in and understanding of environmental issues, biodiversity and sustainable life. The aim of this study is to investigate how well student teachers identify common local species, their interest in and ideas about species identification, and…

Designing an accompanying ecosystem for entrepreneurship students of agronomic and forestry engineering. Opinion and commitment of the faculty

NASA Astrophysics Data System (ADS)

Ortiz, Leovigilda; Fernández-Ahumada, Elvira; Lara-Vélez, Pablo; Taguas, Encarnación V.; Gallardo-Cobos, Rosa; Campillo, M. Carmen; Guerrero-Ginel, José E.

2014-05-01

The current context has called attention to the need of training engineers with new skills beyond the purely technical. Among others, fostering the entrepreneurial spirit has gained special prominence. In the Higher School of Agronomic and Forestry Engineering of the University of Cordoba, a 12-year-experience of an entrepreneurship program for undergraduate students concluded that, for an adequate consolidation and evolution of the program, is important to establish a robust network with active participation of all actors involved. With this antecedent, a collective project conceived as an "ecosystem of support and accompaniment for entrepreneurs" is the approach proposed. The objective is to perform an evaluation of this model in terms of viability, usefulness, actions to be taken and degree of commitment. The key actors identified (undergraduate students, faculty, alumni, local and regional entrepreneurs, enterprises, public administration) have been involved in the evaluation process. This study focuses on the academic staff. For that aim, a survey to the entire faculty (N=128, response rate = 45%) and semi-structured interviews to 20 members have been performed. Data have been treated by means of univariate and multivariate analysis. Results suggest that there exists an agreement concerning the appropriateness of a collective project; there is a critical mass of teachers willing to be engaged; guidelines need to be incorporated in order to facilitate taking on tasks; main restrictions concern the existing asymmetry between formal requirements and those necessary for establishing the ecosystem. ACKNOWLEDGMENT: This research work has been developed in the framework of the ALFA III programme financed by the European Union.

Correlates of elemental-isotopic composition of stream fishes: the importance of land-use, species identity and body size.

PubMed

Montaña, C G; Schalk, C M

2018-04-01

The isotopic (δ 13 C and δ 15 N) and stoichiometric (C:N:P) compositions of four fish species (Family Centrarchidae: Lepomis auritus, Lepomis cyanellus; Family Cyprinidae: Nocomis leptocephalus, Semotilus atromaculatus) were examined across four North Carolina Piedmont streams arrayed along an urbanization gradient. Both isotopic and stoichiometric composition of fishes appeared to track changes occurring in basal resource availability. Values of δ 13 C of basal resources and consumers were more enriched at the most urbanized streams. Similarly, basal resources and consumers were δ 15 N-enriched at more urbanized streams. Basal resource stoichiometry varied across streams, with periphyton being the most variable. Primary consumers stoichiometry also differed across streams. Intraspecific variation in fish stoichiometry correlated with the degree of urbanization, as the two cyprinids had higher N content and L. cyanellus had higher P content in more urbanized streams, probably due to enrichment of basal resources. Intrinsic factors, specifically species identity and body size also affected stoichiometric variation. Phosphorus (P) content increased significantly with body size in centrarchids, but not in cyprinids. These results suggest that although species identity and body size are important predictors of elemental stoichiometry, the complex nature of altered urban streams may yield imbalances in the elemental composition of consumers via their food resources. © 2018 The Fisheries Society of the British Isles.

Bayesian species delimitation in Pleophylla chafers (Coleoptera) - the importance of prior choice and morphology.

PubMed

Eberle, Jonas; Warnock, Rachel C M; Ahrens, Dirk

2016-05-05

Defining species units can be challenging, especially during the earliest stages of speciation, when phylogenetic inference and delimitation methods may be compromised by incomplete lineage sorting (ILS) or secondary gene flow. Integrative approaches to taxonomy, which combine molecular and morphological evidence, have the potential to be valuable in such cases. In this study we investigated the South African scarab beetle genus Pleophylla using data collected from 110 individuals of eight putative morphospecies. The dataset included four molecular markers (cox1, 16S, rrnL, ITS1) and morphometric data based on male genital morphology. We applied a suite of molecular and morphological approaches to species delimitation, and implemented a novel Bayesian approach in the software iBPP, which enables continuous morphological trait and molecular data to be combined. Traditional morphology-based species assignments were supported quantitatively by morphometric analyses of the male genitalia (eigenshape analysis, CVA, LDA). While the ITS1-based delineation was also broadly congruent with the morphospecies, the cox1 data resulted in over-splitting (GMYC modelling, haplotype networks, PTP, ABGD). In the most extreme case morphospecies shared identical haplotypes, which may be attributable to ILS based on statistical tests performed using the software JML. We found the strongest support for putative morphospecies based on phylogenetic evidence using the combined approach implemented in iBPP. However, support for putative species was sensitive to the use of alternative guide trees and alternative combinations of priors on the population size (θ) and rootage (τ 0 ) parameters, especially when the analysis was based on molecular or morphological data alone. We demonstrate that continuous morphological trait data can be extremely valuable in assessing competing hypotheses to species delimitation. In particular, we show that the inclusion of morphological data in an integrative

Importance of Resolving Fungal Nomenclature: the Case of Multiple Pathogenic Species in the Cryptococcus Genus.

PubMed

Hagen, Ferry; Lumbsch, H Thorsten; Arsic Arsenijevic, Valentina; Badali, Hamid; Bertout, Sebastien; Billmyre, R Blake; Bragulat, M Rosa; Cabañes, F Javier; Carbia, Mauricio; Chakrabarti, Arunaloke; Chaturvedi, Sudha; Chaturvedi, Vishnu; Chen, Min; Chowdhary, Anuradha; Colom, Maria-Francisca; Cornely, Oliver A; Crous, Pedro W; Cuétara, Maria S; Diaz, Mara R; Espinel-Ingroff, Ana; Fakhim, Hamed; Falk, Rama; Fang, Wenjie; Herkert, Patricia F; Ferrer Rodríguez, Consuelo; Fraser, James A; Gené, Josepa; Guarro, Josep; Idnurm, Alexander; Illnait-Zaragozi, María-Teresa; Khan, Ziauddin; Khayhan, Kantarawee; Kolecka, Anna; Kurtzman, Cletus P; Lagrou, Katrien; Liao, Wanqing; Linares, Carlos; Meis, Jacques F; Nielsen, Kirsten; Nyazika, Tinashe K; Pan, Weihua; Pekmezovic, Marina; Polacheck, Itzhack; Posteraro, Brunella; de Queiroz Telles, Flavio; Romeo, Orazio; Sánchez, Manuel; Sampaio, Ana; Sanguinetti, Maurizio; Sriburee, Pojana; Sugita, Takashi; Taj-Aldeen, Saad J; Takashima, Masako; Taylor, John W; Theelen, Bart; Tomazin, Rok; Verweij, Paul E; Wahyuningsih, Retno; Wang, Ping; Boekhout, Teun

2017-01-01

Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was done for five genotypes within C. gattii . In a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was premature and without consensus in the community. Although the authors of the perspective recognized the existence of genetic diversity, they preferred the use of the informal nomenclature " C. neoformans species complex" and " C. gattii species complex." Here we highlight the advantage of recognizing these seven species, as ignoring these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances.

Importance of Resolving Fungal Nomenclature: the Case of Multiple Pathogenic Species in the Cryptococcus Genus

PubMed Central

Lumbsch, H. Thorsten; Bertout, Sebastien; Cabañes, F. Javier; Carbia, Mauricio; Chen, Min; Cuétara, Maria S.; Espinel-Ingroff, Ana; Falk, Rama; Ferrer Rodríguez, Consuelo; Fraser, James A.; Khan, Ziauddin; Kurtzman, Cletus P.; Lagrou, Katrien; Liao, Wanqing; Linares, Carlos; Nielsen, Kirsten; Pan, Weihua; Pekmezovic, Marina; Romeo, Orazio; Sánchez, Manuel; Sampaio, Ana; Sriburee, Pojana; Sugita, Takashi; Takashima, Masako; Taylor, John W.; Theelen, Bart; Tomazin, Rok; Verweij, Paul E.; Wahyuningsih, Retno

2017-01-01

ABSTRACT Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was done for five genotypes within C. gattii. In a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was premature and without consensus in the community. Although the authors of the perspective recognized the existence of genetic diversity, they preferred the use of the informal nomenclature “C. neoformans species complex” and “C. gattii species complex.” Here we highlight the advantage of recognizing these seven species, as ignoring these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances. PMID:28875175

Agronomic performance of Populus deltoides trees engineered for biofuel production

DOE PAGES

Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.; ...

2017-11-30

Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust

Agronomic performance of Populus deltoides trees engineered for biofuel production

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

Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.

Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust

Management and conservation of tree squirrels: the importance of endemism, species richness, and forest condition

Treesearch

John L. Koprowski

2005-01-01

Tree squirrels are excellent indicators of forest health yet the taxon is understudied. Most tree squirrels in the Holarctic Region are imperiled with some level of legal protection. The Madrean Archipelago is the epicenter for tree squirrel diversity in North America with 5 endemic species and 2 introduced species. Most species of the region are poorly studied in...

Pest risk assessment of the importation into the United States of unprocessed logs and chips of eighteen Eucalypt species from Australia.

Treesearch

John T. Kliejunas; Harold H., Jr. Burdsall; Gregg A. DeNitto; Andris Eglitis; Dennis A. Haugen; Michael I. Harverty; Jessie A. Micales; Mark R. Powell

2003-01-01

The unmitigated pest risk potential for the importation of unprocessed logs and chips of 18 species of eucalypts (Eucalyptus amygdalina, E. cloeziana, E. delegatensis, E. diversicolor, E. dunnii, E. globulus, E. grandis, E. nitens, E. obliqua, E. ovata, E. pilularis, E. regnans, E. saligna, E. sieberi, E. viminalis, Corymbia calophylla, C. citriodora, and C. maculata)...

Extra-Cellular But Extra-Ordinarily Important for Cells: Apoplastic Reactive Oxygen Species Metabolism

PubMed Central

Podgórska, Anna; Burian, Maria; Szal, Bożena

2017-01-01

Reactive oxygen species (ROS), by their very nature, are highly reactive, and it is no surprise that they can cause damage to organic molecules. In cells, ROS are produced as byproducts of many metabolic reactions, but plants are prepared for this ROS output. Even though extracellular ROS generation constitutes only a minor part of a cell’s total ROS level, this fraction is of extraordinary importance. In an active apoplastic ROS burst, it is mainly the respiratory burst oxidases and peroxidases that are engaged, and defects of these enzymes can affect plant development and stress responses. It must be highlighted that there are also other less well-known enzymatic or non-enzymatic ROS sources. There is a need for ROS detoxification in the apoplast, and almost all cellular antioxidants are present in this space, but the activity of antioxidant enzymes and the concentration of low-mass antioxidants is very low. The low antioxidant efficiency in the apoplast allows ROS to accumulate easily, which is a condition for ROS signaling. Therefore, the apoplastic ROS/antioxidant homeostasis is actively engaged in the reception and reaction to many biotic and abiotic stresses. PMID:28878783

Spatial Distribution of Root and Crown Rot Fungi Associated With Winter Wheat in the North China Plain and Its Relationship With Climate Variables

PubMed Central

Xu, Fei; Yang, Gongqiang; Wang, Junmei; Song, Yuli; Liu, Lulu; Zhao, Kai; Li, Yahong; Han, Zihang

2018-01-01

The distribution frequency of pathogenic fungi associated with root and crown rot of winter wheat (Triticum aestivum) from 104 fields in the North China Plain was determined during the period from 2013 to 2016. The four most important species identified were Bipolaris sorokiniana (24.0% from roots; 33.7% from stems), Fusarium pseudograminearum (14.9% from roots; 27.8% from stems), Rhizoctonia cerealis (1.7% from roots; 4.4% from stems), and Gaeumannomyces graminis var. tritici (9.8% from roots; 4.4% from stems). We observed that the recovered species varied with the agronomic zone. Fusarium pseudograminearum was predominant in regions 1 and 3, whereas F. graminearum, F. acuminatum, and R. cerealis were predominant in regions 2 and 4. The incidence of F. pseudograminearum and R. cerealis was significantly different between regions 1 and 4, while no significant association was found in the distribution of the other species and the agronomic zones. A negative correlation between the frequency of occurrence of F. pseudograminearum and mean annual precipitation during 2013–2016 (r = −0.71; P < 0.01) in the North China Plain and a positive correlation between the mean annual precipitation during 2013–2016 and the frequency of occurrence of F. asiaticum (r = 0.74; P < 0.01) were observed. Several Fusarium species were also found with low frequencies of ~2.1%−3.4 % (F. graminearum, F. acuminatum, and F. sinensis) and ~0.1%−1.3% (F. equiseti, F. oxysporum, F. proliferatum, F. culmorum, F. avenaceum, and F. asiaticum). In more than 93% of the fields, from the root and crown tissues of wheat, two or more root and crown rot species were isolated. The coexistence of Fusarium spp. and B. sorokiniana in one field (65.4%) or in individual plants (11.6%) was more common than for the other species combinations. Moreover, this is the first report on the association between F. sinensis and root and crown rot of wheat. Our results would be useful in the framing guidelines for

Engineering a plant community to deliver multiple ecosystem services.

PubMed

Storkey, Jonathan; Döring, Thomas; Baddeley, John; Collins, Rosemary; Roderick, Stephen; Jones, Hannah; Watson, Christine

2015-06-01

The sustainable delivery of multiple ecosystem services requires the management of functionally diverse biological communities. In an agricultural context, an emphasis on food production has often led to a loss of biodiversity to the detriment of other ecosystem services such as the maintenance of soil health and pest regulation. In scenarios where multiple species can be grown together, it may be possible to better balance environmental and agronomic services through the targeted selection of companion species. We used the case study of legume-based cover crops to engineer a plant community that delivered the optimal balance of six ecosystem services: early productivity, regrowth following mowing, weed suppression, support of invertebrates, soil fertility building (measured as yield of following crop), and conservation of nutrients in the soil. An experimental species pool of 12 cultivated legume species was screened for a range of functional traits and ecosystem services at five sites across a geographical gradient in the United Kingdom. All possible species combinations were then analyzed, using a process-based model of plant competition, to identify the community that delivered the best balance of services at each site. In our system, low to intermediate levels of species richness (one to four species) that exploited functional contrasts in growth habit and phenology were identified as being optimal. The optimal solution was determined largely by the number of species and functional diversity represented by the starting species pool, emphasizing the importance of the initial selection of species for the screening experiments. The approach of using relationships between functional traits and ecosystem services to design multifunctional biological communities has the potential to inform the design of agricultural systems that better balance agronomic and environmental services and meet the current objective of European agricultural policy to maintain viable food

Phylogenetic study of the Colletotrichum species on imported citrus fruits uncovers a low diversity and a new species in the Colletotrichum gigasporum complex.

PubMed

Douanla-Meli, Clovis; Unger, Jens-Georg

2017-10-01

Colletotrichum species associated with citrus fruits are fragmentarily known and it lacks accordingly accurate information on the diversity carried alongside the trade of these commodities from producer countries to Europe. In this study, we investigated the molecular phylogenetic diversity, colonisation, and prevalence of Colletotrichum isolated from asymptomatic and diseased tissues of nine citrus fruit species from 17 geographically diverse countries. Totally 454 isolates were morphoculturally characterised, and multilocus analyses (ACT, ApMat, CHS-1, GAPDH, ITS, TUB2) was performed on a subset of representative morphotype isolates. Results led to the identification of three previously known species (Colletotrichum gloeosporioides, Colletotrichum karstii, Colletotrichum siamense) and one novel lineage comprising endophytic isolates from Citrus maxima. Based on this lineage, Colletotrichum citri-maximae is described as a new species in the Colletotrichum gigasporum complex, and is characterised by a long deletion in the GAPDH sequence, a character shared with three of its phylogenetic sister taxa. Prevalence of Colletotrichum varied among citrus species and was greatest on Citrus sinensis fruits. C. gloeosporioides was the most common species followed by C. siamense. Except for the new species, all other isolated Colletotrichum spp. also colonise citrus leaves, but the overall diversity on fruits may be lower than that of leaves. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Formation of hydrothermal tin deposits: Raman spectroscopic evidence for an important role of aqueous Sn(IV) species

NASA Astrophysics Data System (ADS)

Schmidt, Christian

2018-01-01

The speciation of tin and the solubility of cassiterite in H2O + HCl were determined at temperatures to 600 °C using in situ Raman spectroscopy. In addition, information on the fluid-melt partition of Sn was obtained at 700 °C and indicated a preference of the fluid only at HCl concentrations that are much higher than in fluids exsolved from natural felsic melts. Dissolution of cassiterite generally resulted in formation of Sn(IV) species unless reduced conditions were generated by hydrogen permeation or carbohydrates in the starting material. The prevalent aqueous Sn(IV) species was [SnCl4(H2O)2]0, with additional [SnCl3(H2O)3]+ and [SnCl5(H2O)]-. The only detectable Sn(II) species was very likely [Sn(II)Cl3]-. Cassiterite solubility increased with HCl concentration and was generally high in H2O+HCl fluids, with no strong dependencies on temperature, pressure, or the oxidation state of tin in the fluid. The Sn(IV) concentrations at 500 and 600 °C determined from the integrated ν1[Sn(IV)sbnd Cl] band intensity are in good agreement with literature data on the cassiterite solubility in H2O + HCl at oxygen fugacities along the hematite-magnetite buffer. The combined results from previous experimental studies and this study demonstrate that HCl molality is a crucial parameter for hydrothermal mobilization and transport of tin and for cassiterite precipitation, and that pH, pressure and temperature are less important. Current models on hydrothermal tin deposit formation need to be augmented to include Sn(IV)sbnd Cl complexes as significant tin-transporting species. Irrespective of the oxidation state of tin in the fluid, cassiterite precipitates due to reaction of the hydrothermal fluid with the wall rock (greisen or skarn formation), dilution (mixing with meteoric water) or a decrease in the HCl activity in the aqueous liquid by boiling. A redox reaction is only required for tin transported as Sn(II) to be converted to Sn(IV).

Crosses prior to parthenogenesis explain the current genetic diversity of tropical plant-parasitic Meloidogyne species (Nematoda: Tylenchida).

PubMed

Fargette, Mireille; Berthier, Karine; Richaud, Myriam; Lollier, Virginie; Franck, Pierre; Hernandez, Adan; Frutos, Roger

2010-08-01

The tropical and subtropical parthenogenetic plant-parasitic nematodes Meloidogyne are polyphagous major agricultural pests. Implementing proper pest management approaches requires a good understanding of mechanisms, population structure, evolutionary patterns and species identification. A comparative analysis of the mitochondrial vs nuclear diversity was conducted on a selected set of Meloidogyne lines from various geographic origins. Mitochondrial co2-16S sequences and AFLP markers of total DNA were applied because of their ability to evidence discrete genetic variation between closely related isolates. Several distinct maternal lineages were present, now associated with different genetic backgrounds. Relative discordances were found when comparing mitochondrial and nuclear diversity patterns. These patterns are most likely related to crosses within one ancestral genetic pool, followed by the establishment of parthenogenesis. In this case, they mirror the genetic backgrounds of the original individuals. Another aspect could be that species emergence was recent or on process from this original genetic pool and that the relatively short time elapsed since then and before parthenogenesis settlement did not allow for lineage sorting. This could also be compatible with the hypothesis of hybrids between closely related species. This genetic pool would correspond to a species as defined by the species interbreeding concept, but also including the grey area of species boundaries. This complex process has implications on the way genotypic and phenotypic diversity should be addressed. The phenotype of parthenogenetic lines is at least for part determined by the ancestral amphimictic genetic background. A direct consequence is, therefore, in terms of risk management, the limited confidence one can have on the direct association of an agronomic threat to a simple typing or species delineation. Risk management strategies and tools must thus consider this complexity when

Quantitative trait loci affecting oil content, oil composition, and other agronomically important traits in Oat (Avena sativa L.)

USDA-ARS?s Scientific Manuscript database

Groat oil content and composition are important determinants of oat quality. We investigated these traits in a population of 146 recombinant inbred lines from a cross between 'Dal' (high oil) and 'Exeter' (low oil). A linkage map consisting of 475 DArT markers spanning 1271.8 cM across 40 linkage gr...

Resilience of the Eastern Chukchi Sea Food Web to Mortality Based Perturbations and Identification of Ecologically Important Species

NASA Astrophysics Data System (ADS)

Whitehouse, G. A.; Aydin, K.

2016-02-01

Evidence of climate impacts on Arctic marine ecosystems is accumulating and Arctic marine ecosystems face additional pressures that may accompany increasing human activities due to improved access following reductions in sea ice cover. Thus, there is growing demand for information on how Arctic ecosystems may respond to potential disturbance. We explore the response of the eastern Chukchi Sea food web to mortality based perturbations using the dynamic food web modeling framework, Ecopath with Ecosim. We generated thousands of ecosystems by drawing random sets of model parameters from informative prior distributions and only retained those ecosystems that resulted in plausible, numerically stable configurations (no extinctions or population growth without limit). To perturb the systems, we increased mortality rates for selected functional groups then ran the retained models forward 50 years to examine how the biomass of other functional groups responded, and evaluated the resilience of the food web as the time for all functional groups to return to within 10 percent of their starting biomass. Ecologically important species were identified as those species (or functional groups of species) for whom changes in mortality had the greatest effect on the remainder of the food web. We also report on how a selection of ecosystem scale properties were affected by selected perturbations, including mean biomass longevity, the distribution of biomass across trophic levels, and a selection of dimensionless biomass ratios. These perturbations simulate a range of potential impacts that mortality events may have on the food web of the eastern Chukchi Sea, and indicate the directional response of other species and functional groups to these simulated events. This information will be of value to decision makers and resource managers developing guidelines for commercial and industrial development in the eastern Chukchi Sea.

A Data-driven Approach to Integrate Crop Rotation Agronomic Practices in a Global Gridded Land-use Forcing Dataset

NASA Astrophysics Data System (ADS)

Sahajpal, R.; Hurtt, G. C.; Chini, L. P.; Frolking, S. E.; Izaurralde, R. C.

2016-12-01

Agro-ecosystems are the dominant land-use type on Earth, covering more than a third of ice-free land surface. Agricultural practices have influenced the Earth's climate system by significantly altering the biogeophysical and biogeochemical properties from hyper-local to global scales. While past work has focused largely on characterizing the effects of net land cover changes, the magnitude and nature of gross transitions and agricultural management practices on climate remains highly uncertain. To address this issue, a new set of global gridded land-use forcing datasets (LUH2) have been developed in a standard format required by climate models for CMIP6. For the first time, this dataset includes information on key agricultural management practices including crop rotations. Crop rotations describe the practice of growing crops on the same land in sequential seasons and are essential to agronomic management as they influence key ecosystem services such as crop yields, water quality, carbon and nutrient cycling, pest and disease control. Here, we present a data-driven approach to infer crop rotations based on crop specific land cover data, derived from moderate resolution satellite imagery and created at an annual time-step for the continental United States. Our approach compresses the more than 100,000 unique crop rotations prevalent in the United States from 2013 - 2015 to about 200 representative crop rotations that account for nearly 80% of the spatio-temporal variability. Further simplification is achieved by mapping individual crops to crop functional types, which identify crops based on their photosynthetic pathways (C3/C4), life strategy (annual/perennial) and whether they are N-fixing or not. The resulting matrix of annual transitions between crop functional types averages 41,000 km2/yr for rotations between C3 and C4 annual crops, and 140,000 km2/yr between C3 N-fixing and C4 annual crops. The crop rotation matrix is combined with information on other land

Trait-abundance relation in response to nutrient addition in a Tibetan alpine meadow: The importance of species trade-off in resource conservation and acquisition.

PubMed

Liu, Huiying; Li, Ying; Ren, Fei; Lin, Li; Zhu, Wenyan; He, Jin-Sheng; Niu, Kechang

2017-12-01

In competition-dominated communities, traits promoting resource conservation and competitive ability are expected to have an important influence on species relative abundance (SRA). Yet, few studies have tested the trait-abundance relations in the line of species trade-off in resource conservation versus acquisition, indicating by multiple traits coordination. We measured SRA and key functional traits involving leaf economic spectrum (SLA, specific leaf area; LDMC, leaf dry matter content; LCC, leaf carbon concentration; LNC, leaf nitrogen concentration; LPC, leaf phosphorus concentration; Hs, mature height) for ten common species in all plots subjected to addition of nitrogen fertilizer (N), phosphorus fertilizer (P), or both of them (NP) in a Tibetan alpine meadow. We test whether SRA is positively related with traits promoting plant resource conservation, while negatively correlated with traits promoting plant growth and resource acquisition. We found that species were primarily differentiated along a trade-off axis involving traits promoting nutrient acquisition and fast growth (e.g., LPC and SLA) versus traits promoting resource conservation and competition ability (e.g., large LDMC). We further found that SRA was positively correlated with plant height, LDMC, and LCC, but negatively associated with SLA and leaf nutrient concentration irrespective of fertilization. A stronger positive height-SRA was found in NP-fertilized plots than in other plots, while negative correlations between SRA and SLA and LPC were found in N or P fertilized plots. The results indicate that species trade-off in nutrient acquisition and resource conservation was a key driver of SRA in competition-dominated communities following fertilization, with the linkage between SRA and traits depending on plant competition for specific soil nutrient and/or light availability. The results highlight the importance of competitive exclusion in plant community assembly following fertilization and

Reactive Oxygen Species Scavenging by Catalase Is Important for Female Lutzomyia longipalpis Fecundity and Mortality

PubMed Central

Diaz-Albiter, Hector; Mitford, Roanna; Genta, Fernando A.; Sant'Anna, Mauricio R. V.; Dillon, Rod J.

2011-01-01

The phlebotomine sand fly Lutzomyia longipalpis is the most important vector of American visceral leishmaniasis (AVL), the disseminated and most serious form of the disease in Central and South America. In the natural environment, most female L. longipalpis are thought to survive for less than 10 days and will feed on blood only once or twice during their lifetime. Successful transmission of parasites occurs when a Leishmania-infected female sand fly feeds on a new host. Knowledge of factors affecting sand fly longevity that lead to a reduction in lifespan could result in a decrease in parasite transmission. Catalase has been found to play a major role in survival and fecundity in many insect species. It is a strong antioxidant enzyme that breaks down toxic reactive oxygen species (ROS). Ovarian catalase was found to accumulate in the developing sand fly oocyte from 12 to 48 hours after blood feeding. Catalase expression in ovaries as well as oocyte numbers was found to decrease with age. This reduction was not found in flies when fed on the antioxidant ascorbic acid in the sugar meal, a condition that increased mortality and activation of the prophenoloxidase cascade. RNA interference was used to silence catalase gene expression in female Lu. longipalpis. Depletion of catalase led to a significant increase of mortality and a reduction in the number of developing oocytes produced after blood feeding. These results demonstrate the central role that catalase and ROS play in the longevity and fecundity of phlebotomine sand flies. PMID:21408075

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.

Bio-effectors from waste materials as growth promoters for tomato plants, an agronomic and metabolomic study

NASA Astrophysics Data System (ADS)

Abou Chehade, Lara; Chami, Ziad Al; De Pascali, Sandra; Cavoski, Ivana; Fanizzi, Francesco Paolo

2015-04-01

In organic farming, where nutrient management is constrained and sustainability is claimed, bio-effectors pave their way. Considering selected bio-effectors, this study integrates metabolomics to agronomy in depicting induced relevant phenomena. Extracts of three agro-industrial wastes (Lemon processing residues, Fennel processing residues and Brewer's spent grain) are being investigated as sources of bio-effectors for the third trial consequently. Corresponding individual and mixture aqueous extracts are assessed for their synergistic and/or single agronomic and qualitative performances on soil-grown tomato, compared to both a control and humic acid treatments. A metabolomic profiling of tomato fruits via the Proton Nuclear Magnetic Resonance (NMR) spectroscopy, as holistic indicator of fruit quality and extract-induced responses, complements crop productivity and organoleptic/nutritional qualitative analyses. Results are expected to show mainly an enhancement of the fruit qualitative traits, and to confirm partly the previous results of better crop productivity and metabolism enhancement. Waste-derived bio-effectors could be, accordingly, demonstrated as potential candidates of plant-enhancing substances. Keywords: bio-effectors, organic farming, agro-industrial wastes, nuclear magnetic resonance (NMR), tomato.

Life-history traits and effective population size in species with overlapping generations revisited: the importance of adult mortality.

PubMed

Waples, R S

2016-10-01

The relationship between life-history traits and the key eco-evolutionary parameters effective population size (Ne) and Ne/N is revisited for iteroparous species with overlapping generations, with a focus on the annual rate of adult mortality (d). Analytical methods based on populations with arbitrarily long adult lifespans are used to evaluate the influence of d on Ne, Ne/N and the factors that determine these parameters: adult abundance (N), generation length (T), age at maturity (α), the ratio of variance to mean reproductive success in one season by individuals of the same age (φ) and lifetime variance in reproductive success of individuals in a cohort (Vk•). Although the resulting estimators of N, T and Vk• are upwardly biased for species with short adult lifespans, the estimate of Ne/N is largely unbiased because biases in T are compensated for by biases in Vk• and N. For the first time, the contrasting effects of T and Vk• on Ne and Ne/N are jointly considered with respect to d and φ. A simple function of d and α based on the assumption of constant vital rates is shown to be a robust predictor (R(2)=0.78) of Ne/N in an empirical data set of life tables for 63 animal and plant species with diverse life histories. Results presented here should provide important context for interpreting the surge of genetically based estimates of Ne that has been fueled by the genomics revolution.

A novel method for assessing risks to pollinators from plant protection products using honeybees as a model species.

PubMed

Barmaz, Stefania; Potts, Simon G; Vighi, Marco

2010-10-01

Pollination is one of the most important ecosystem services in agroecosystems and supports food production. Pollinators are potentially at risk being exposed to pesticides and the main route of exposure is direct contact, in some cases ingestion, of contaminated materials such as pollen, nectar, flowers and foliage. To date there are no suitable methods for predicting pesticide exposure for pollinators, therefore official procedures to assess pesticide risk are based on a Hazard Quotient. Here we develop a procedure to assess exposure and risk for pollinators based on the foraging behaviour of honeybees (Apis mellifera) and using this species as indicator representative of pollinating insects. The method was applied in 13 European field sites with different climatic, landscape and land use characteristics. The level of risk during the crop growing season was evaluated as a function of the active ingredients used and application regime. Risk levels were primarily determined by the agronomic practices employed (i.e. crop type, pest control method, pesticide use), and there was a clear temporal partitioning of risks through time. Generally the risk was higher in sites cultivated with permanent crops, such as vineyard and olive, than in annual crops, such as cereals and oil seed rape. The greatest level of risk is generally found at the beginning of the growing season for annual crops and later in June-July for permanent crops.

Prevalence of SGHV among tsetse species of economic importance in Tanzania and their implication for SIT application.

PubMed

Malele, Imna I; Manangwa, Oliver; Nyingilili, Hamisi H; Kitwika, Winston A; Lyaruu, Eugene A; Msangi, Atway R; Ouma, Johnson O; Nkwangulila, Gamba; Abd-Alla, Adly M M

2013-03-01

Sterile Insect technique is an important component in area-wide integrated tsetse control. The presence of the salivary glands hypertrophy virus (SGHV) in the wild tsetse, which are the seeds for colony adaptations in the laboratory has become a stumbling block in establishing and maintaining colonies in the laboratory. The virus is transmitted both vertically (in the wild) and horizontally (in the laboratory). However, its prevalence is magnified in the laboratory as a result of the use of in vitro membrane feeding regimen. Fly species of Glossina fuscipes fuscipes, G. pallidipes, G. morsitans and G. swynnertoni were collected from the coastal and inland areas of Tanzania and virus infection rates were assessed microscopically and by PCR. The data showed that in a period of 4years, the virus was present in all species tested irrespective of their ages, sex, and season of the year. However, infection levels differed among species and from one location to another. Symptomatic infection determined by dissection was 1.2% (25/2164) from the coast as compared to 0.4% (6/1725) for inland collected flies. PCR analysis indicated a higher infection rate of 19.81% (104/525) of asymptomatic flies. From these observations, we conclude that care should be taken when planning to initiate tsetse laboratory colonies for use in SIT eradication program. All efforts should be made to select non-infected flies when initiating laboratory colonies and to try to minimize the infection with SGHV. Also management of SGHV infection in the established colony should be applied. Copyright © 2013 International Atomic Energy Agency. Published by Elsevier Inc. All rights reserved.

QTL and QTL x environment effects on agronomic and nitrogen acquisition traits in rice.

PubMed

Senthilvel, Senapathy; Vinod, Kunnummal Kurungara; Malarvizhi, Palaniappan; Maheswaran, Marappa

2008-09-01

Agricultural environments deteriorate due to excess nitrogen application. Breeding for low nitrogen responsive genotypes can reduce soil nitrogen input. Rice genotypes respond variably to soil available nitrogen. The present study attempted quantification of genotype x nitrogen level interaction and mapping of quantitative trait loci (QTLs) associated with nitrogen use efficiency (NUE) and other associated agronomic traits. Twelve parameters were observed across a set of 82 double haploid (DH) lines derived from IR64/Azucena. Three nitrogen regimes namely, native (0 kg/ha; no nitrogen applied), optimum (100 kg/ha) and high (200 kg/ha) replicated thrice were the environments. The parents and DH lines were significantly varying for all traits under different nitrogen regimes. All traits except plant height recorded significant genotype x environment interaction. Individual plant yield was positively correlated with nitrogen use efficiency and nitrogen uptake. Sixteen QTLs were detected by composite interval mapping. Eleven QTLs showed significant QTL x environment interactions. On chromosome 3, seven QTLs were detected associated with nitrogen use, plant yield and associated traits. A QTL region between markers RZ678, RZ574 and RZ284 was associated with nitrogen use and yield. This chromosomal region was enriched with expressed gene sequences of known key nitrogen assimilation genes.

Agronomical, biochemical and histological response of resistant and susceptible wheat and barley under BYDV stress

PubMed Central

Choudhury, Shormin; Hu, Hongliang; Larkin, Philip; Meinke, Holger; Shabala, Sergey; Ahmed, Ibrahim

2018-01-01

Barley yellow dwarf virus-PAV (BYDV-PAV) is one of the major viruses causing a widespread and serious viral disease affecting cereal crops. To gain a better understanding of plant defence mechanisms of BYDV resistance genes (Bdv2 and RYd2) against BYDV-PAV infection, the differences in agronomical, biochemical and histological changes between susceptible and resistant wheat and barley cultivars were investigated. We found that root growth and total dry matter of susceptible cultivars showed greater reduction than that of resistant ones after infection. BYDV infected leaves in susceptible wheat and barley cultivars showed a significant reduction in photosynthetic pigments, an increase in the concentration of reducing sugar. The protein levels were also low in infected leaves. There was a significant increase in total phenol contents in resistant cultivars, which might reflect a protective mechanism of plants against virus infection. In phloem tissue, sieve elements (SE) and companion cells (CC) were severely damaged in susceptible cultivars after infection. It is suggested that restriction of viral movement in the phloem tissue and increased production of phenolic compounds may play a role in the resistance and defensive mechanisms of both Bdv2 and RYd2 against virus infection. PMID:29868264

Scanning electron microscopic studies on antenna of Hemipyrellia ligurriens (Wiedemann, 1830) (Diptera: Calliphoridae)-A blow fly species of forensic importance.

PubMed

Hore, Garima; Maity, Aniruddha; Naskar, Atanu; Ansar, Waliza; Ghosh, Shyamasree; Saha, Goutam Kumar; Banerjee, Dhriti

2017-08-01

Blow flies (Diptera: Calliphoridae) are one of the foremost organisms amongst forensic insects to colonize corpses shortly after death, thus are of immense importance in the domain of forensic entomology. The blow fly Hemipyrellia ligurriens (Wiedemann, 1830) (Diptera: Calliphoridae) is considered as a forensically important fly species globally and is also known for its medical and veterinary importance. In the present study, we report for the first time scanning electron microscopic studies on the morphology of sensilla of antenna of adult male and female of H. ligurriens is with profound importance in better understanding of the insect morphology from forensic entomological perspective, and also could aid in proper identification of the species from other calliphorid flies. The structural peculiarities observed in the (i) antenna of H. ligurriens with three segments- scape, pedicel and flagellum with dorso-laterally placed arista (ii) densely covered microtrichia and most abundant trichoid sensilla identified on the antenna (iii) observation of only one type of sensilla, chaetic sensilla (ChI) on the scape (iv) two types of chaetic sensilla (ChI and ChII) and styloconic sensilla on the pedicel (v) the flagellum with three types of sensilla- trichoid, basiconic and coeloconic sensilla (vi) Basiconic sensilla with multiporous surfaces with characteristic olfactory function. Moderate sexual dimorphism in the width of the flagellum, the females with wider flagella than the males, bear significance to the fact that they bear more multi-porous sensilla than the males, thus suffice their need to detect oviposition sites. Significant difference was observed in the length and width of coeloconic sensilla between the two sexes, the females showed bigger coeloconic sensilla, suggesting their function in oviposition site detection and successful colonization in corpses. Copyright © 2017 Elsevier B.V. All rights reserved.

Cophylogeny of the anther smut fungi and their caryophyllaceous hosts: Prevalence of host shifts and importance of delimiting parasite species for inferring cospeciation

PubMed Central

2008-01-01

, cospeciation events were not more frequent than expected under a random distribution, and many host shifts were inferred. Current geographic distributions of host species seemed to be of little relevance for understanding the putative historical host shifts, because most fungal species had overlapping geographic ranges. We did detect some ecological similarities, including shared pollinators and habitat types, between host species that were diseased by closely related anther smut species. Overall, genetic similarity underlying the host-parasite interactions appeared to have the most important influence on specialization and host-shifts: generalist multi-host parasite species were found on closely related plant species, and related species in the Microbotryum phylogeny were associated with members of the same host clade. Conclusion We showed here that Microbotryum species have evolved through frequent host shifts to moderately distant hosts, and we show further that accurate delimitation of parasite species is essential for interpreting cophylogeny studies. PMID:18371215

Assessing food web dynamics and relative importance of organic matter sources for fish species in two Portuguese estuaries: a stable isotope approach.

PubMed

França, Susana; Vasconcelos, Rita P; Tanner, Susanne; Máguas, Cristina; Costa, Maria José; Cabral, Henrique N

2011-10-01

Stable carbon and nitrogen isotopes (δ¹³C, δ¹⁵N) were used to analyse food web dynamics of two of the main estuaries of the Portuguese coast: Tejo and Mira. The ultimate sources of organic matter supporting production of some of the most abundant and commercially important fish species were determined; and seasonal, inter- and intra- estuarine differences in the trophic relations among producers and consumers were identified. Stable isotope analysis was performed in different producers, primary consumers (main prey items for fish) and fish species (Solea solea, Solea senegalensis, Pomatoschistus microps, Dicentrarchus labrax, Liza ramada, Diplodus vulgaris and Atherina presbyter) of two areas in each estuary, in July and October 2009. Model calculations showed that the main prey for the fish species in the Tejo estuary used mostly salt marsh-derived organic matter as nutritional sources, with no marked differences between the sampled months. Trophic levels of fish species from the same estuary differed at multiple scales: inter-species, seasonally and spatially (both between and within estuaries). Significant differences in isotopic composition of fish species were more pronounced spatially (between the two sampled areas in the estuary) than seasonally (between sampled months). Trophic relationships in both estuaries demonstrated that organic matter is transferred to higher trophic positions mainly through benthic pathways. This shows the flexibility of these species to share resources and to exploit temporary peaks in prey populations. The present results showed that extensive disturbance in intertidal habitats from both estuaries may potentially change the balance of organic matter in the base of these complex food webs. Copyright © 2011 Elsevier Ltd. All rights reserved.

[Species identification in 5 imported cases previously diagnosed as Vivax malaria by parasitological and nested PCR techniques].

PubMed

Yao, Li-Nong; Zhang, Ling-Ling; Ruan, Wei; Chen, Hua-Liang; Lu, Qiao-Yi; Yang, Ting-Ting

2013-06-01

To identify the species of malaria parasites in 5 imported cases previously diagnosed as vivax malaria. Epidemiological information and blood samples were collected from five patients who returned from Africa and were diagnosed as vivax malaria. The detection was conducted by microscopy, right VIEW rapid malaria test (RDTs) and nested PCR with Plasmodium genus-specific and species-specific primers. The amplified products were sequenced and Blast analysis was performed. Three of the 5 cases had a history of malaria attack. Microscopically, 4 cases were confirmed as Plasmodium ovale infection, 1 (case 1) was co-infected with P. vivax and P. ovale. All 5 cases showed negative RDT results. Nested PCR detection revealed that the 5 cases had a P. ovale-specific fragment (800 bp), while case 1 had a P. vivax-specific fragment (120 bp) concurrently. Blast analysis showed that the amplified sequence of the 5 cases had a high sequence homology (99%) with P. ovale gene for small subunit ribosomal RNA from GenBank, and that of case 1 also shared 99% homology with P. vivax isolate SV5 18S ribosomal RNA gene (GenBank accession number: JQ627157.1). Among the five cases, four were infected by Plasmodium ovale, and one was co-infected with both P. vivax and P. ovale.

Effects of herbicides on some important brush species in southwestern Oregon.

Treesearch

H. Gratkowski

1959-01-01

A series of screening tests were established during 1955 to determine the effects of six commercial and experimental herbicides on brush in southwestern Oregon. The herbicides were tested as foliage sprays on 13 of the most abundant species and varieties of brush on forest lands in this area. Low volatile esters of 2, 4-D and 2,4, 5-T proved to be the most effective...

The importance of considering rainfall partitioning in afforestation initiatives in semiarid climates: A comparison of common planted tree species in Tehran, Iran.

PubMed

Sadeghi, Seyed Mohammad Moein; Attarod, Pedram; Van Stan, John Toland; Pypker, Thomas Grant

2016-10-15

As plantations become increasingly important sources of wood and fiber in arid/semiarid places, they have also become increasingly criticized for their hydrological impacts. An examination and comparison of gross rainfall (GR) partitioning across commonly-planted tree species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia, and Fraxinus rotundifolia) in semiarid regions has great value for watershed and forest managers interested in managing canopy hydrological processes for societal benefit. Therefore, we performed a field study examining GR partitioning into throughfall (TF), stemflow (SF), and rainfall interception (I) for these species in the semiarid Chitgar Forest Park, Tehran, Iran. An advantage to our study is that we explore the effects of forest structural differences in plantation forests experiencing similar climatic factors and storm conditions. As such, variability in GR partitioning due to different meteorological conditions is minimized, allowing comparison of structural attributes across plantations. Our results show that commonly-selected afforestation species experiencing the same climate produced differing stand structures that differentially partition GR into TF, SF, and I. P. eldarica might be the best of the four species to plant if the primary goal of afforestation is to limit erosion and stormwater runoff as it intercepted more rainfall than other species. However, the high SF generation from F. rotundifolia, and low GR necessary to initiate SF, could maximize retention of water in the soils since SF has been shown to infiltrate along root pathways and access groundwater. A consideration of GR partitioning should be considered when selecting a species for afforestation/reforestation in water-limited ecosystems. Copyright © 2016 Elsevier B.V. All rights reserved.

Establishment of native species on a natural gas pipeline: the importance of seeding rate, aspect, and species selection

Treesearch

Melissa A. Thomas-Van Gundy; Pamela J. Edwards; Thomas M. Schuler

2018-01-01

With the increase in natural gas production in the United States, land managers need solutions and best practices to mitigate potential negative impacts of forest and soil disturbance and meet landowner objectives and desired conditions. Mitigation often includes the use of native seed mixes for maintaining plant diversity, controlling nonnative invasive species, and...

Desulfovibrio species are potentially important in regressive autism.

PubMed

Finegold, Sydney M

2011-08-01

Autism is a complex disorder with no specific diagnostic test so the disease is defined by its characteristics including cognitive defects, social, communication and behavioral problems, repetitive behaviors, unusual sensitivity to stimuli such as noise, restricted interests, and self stimulation. The incidence of this disease has increased remarkably in recent years and was 110/10,000 children (∼1%) in multiple areas of the US in 2007. The financial burden on families and communities is enormous. In terms of predisposing factors, heredity plays a role in some subjects, but it is clear that environmental factors are also important. Environmental toxins can affect the immune system adversely. Intestinal bacteria are recognized by a few investigators as potentially important and we have proposed that certain antimicrobial drugs may be a key factor in modifying the intestinal bacterial flora adversely, selecting out potentially harmful bacteria that are normally suppressed by an intact normal intestinal flora. We had felt that clostridia in the gut might be involved in autism because they are virulent organisms and spore-formers; spores would resist antibacterial agents so that when antibiotics were discontinued the spores would germinate and by toxin production or another mechanism lead to autism. However, a recent study of ours employing the powerful pyrosequencing technique on stools of subjects with regressive autism showed that Desulfovibrio was more common in autistic subjects than in controls. We subsequently confirmed this with pilot cultural and real-time PCR studies and found siblings of autistic children had counts of Desulfovibrio that were intermediate, suggesting possible spread of the organism in the family environment. Desulfovibrio is an anaerobic bacillus that does not produce spores but is nevertheless resistant to aerobic and other adverse conditions by other mechanisms and is commonly resistant to certain antimicrobial agents (such as

The importance of scaling for detecting community patterns: success and failure in assemblages of introduced species

USGS Publications Warehouse

Allen, Craig R.; Angeler, David G.; Moulton, Michael P.; Holling, Crawford S.

2015-01-01

Community saturation can help to explain why biological invasions fail. However, previous research has documented inconsistent relationships between failed invasions (i.e., an invasive species colonizes but goes extinct) and the number of species present in the invaded community. We use data from bird communities of the Hawaiian island of Oahu, which supports a community of 38 successfully established introduced birds and where 37 species were introduced but went extinct (failed invasions). We develop a modified approach to evaluate the effects of community saturation on invasion failure. Our method accounts (1) for the number of species present (NSP) when the species goes extinct rather than during its introduction; and (2) scaling patterns in bird body mass distributions that accounts for the hierarchical organization of ecosystems and the fact that interaction strength amongst species varies with scale. We found that when using NSP at the time of extinction, NSP was higher for failed introductions as compared to successful introductions, supporting the idea that increasing species richness and putative community saturation mediate invasion resistance. Accounting for scale-specific patterns in body size distributions further improved the relationship between NSP and introduction failure. Results show that a better understanding of invasion outcomes can be obtained when scale-specific community structure is accounted for in the analysis.

Multiple mechanisms enable invasive species to suppress native species.

PubMed

Bennett, Alison E; Thomsen, Meredith; Strauss, Sharon Y

2011-07-01

Invasive plants represent a significant threat to ecosystem biodiversity. To decrease the impacts of invasive species, a major scientific undertaking of the last few decades has been aimed at understanding the mechanisms that drive invasive plant success. Most studies and theories have focused on a single mechanism for predicting the success of invasive plants and therefore cannot provide insight as to the relative importance of multiple interactions in predicting invasive species' success. We examine four mechanisms that potentially contribute to the success of invasive velvetgrass Holcus lanatus: direct competition, indirect competition mediated by mammalian herbivores, interference competition via allelopathy, and indirect competition mediated by changes in the soil community. Using a combination of field and greenhouse approaches, we focus on the effects of H. lanatus on a common species in California coastal prairies, Erigeron glaucus, where the invasion is most intense. We found that H. lanatus had the strongest effects on E. glaucus via direct competition, but it also influenced the soil community in ways that feed back to negatively influence E. glaucus and other native species after H. lanatus removal. This approach provided evidence for multiple mechanisms contributing to negative effects of invasive species, and it identified when particular strategies were most likely to be important. These mechanisms can be applied to eradication of H. lanatus and conservation of California coastal prairie systems, and they illustrate the utility of an integrated set of experiments for determining the potential mechanisms of invasive species' success.

The Importance of Interspecific Interactions on the Present Range of the Invasive Mosquito Aedes albopictus (Diptera: Culicidae) and Persistence of Resident Container Species in the United States.

PubMed

Fader, Joseph E

2016-09-01

Aedes albopictus (Skuse) established in the United States over 30 yr ago and quickly spread throughout the entire eastern half of the country. It has recently spread into western regions and projected climate change scenarios suggest continued expansion to the west and north. Aedes albopictus has had major impacts on, and been impacted by, a diverse array of resident mosquito species. Laying eggs at the edges of small, water-holding containers, hatched larvae develop within these containers feeding on detritus-based resources. Under limited resource conditions, Ae. albopictus has been shown to be a superior competitor to essentially all native and resident species in the United States. Adult males also mate interspecifically with at least one resident species with significant negative impacts on reproductive output for susceptible females. Despite these strong interference effects on sympatric species, competitor outcomes have been highly variable, ranging from outright local exclusion by Ae. albopictus, to apparent exclusion of Ae. albopictus in the presence of the same species. Context-dependent mechanisms that alter the relative strengths of inter- and intraspecific competition, as well as rapid evolution of satyrization-resistant females, may help explain these patterns of variable coexistence. Although there is a large body of research on interspecific interactions of Ae. albopictus in the United States, there remain substantial gaps in our understanding of the most important species interactions. Addressing these gaps is important in predicting the future distribution of this species and understanding consequences for resident species, including humans, that interact with this highly invasive mosquito. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Plasma membrane theory in nutrient uptake and rhizotoxicity

USDA-ARS?s Scientific Manuscript database

A clear understanding of plant-ion interactions is required to address problems of plant nutrition, toxicity, and the alleviation of toxicity. One or a combination of these problems limits productivity and persistence of pasture species (and other agronomic species) in vast regions of the world. F...

Evaluation of achenes of Helianthus verticillatus, an endemic sunflower of the southeastern US for oil concentration and fatty acid composition

USDA-ARS?s Scientific Manuscript database

The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from the wild species which have provided a continued source of desirable agronomic traits. The genus Helianthus comprises 51 species, 14 annual and 37 perennial, all native to North America. Whorled sunflowe...

Non-lethal effects of an invasive species in the marine environment: the importance of early life-history stages.

PubMed

Rius, Marc; Turon, Xavier; Marshall, Dustin J

2009-04-01

Studies examining the effects of invasive species have focussed traditionally on the direct/lethal effects of the invasive on the native community but there is a growing recognition that invasive species may also have non-lethal effects. In terrestrial systems, non-lethal effects of invasive species can disrupt early life-history phases (such as fertilisation, dispersal and subsequent establishment) of native species, but in the marine environment most studies focus on adult rather than early life-history stages. Here, we examine the potential for an introduced sessile marine invertebrate (Styela plicata) to exert both lethal and non-lethal effects on a native species (Microcosmus squamiger) across multiple early life-history stages. We determined whether sperm from the invasive species interfered with the fertilisation of eggs from the native species and found no effect. However, we did find strong effects of the invasive species on the post-fertilisation performance of the native species. The invasive species inhibited the settlement of native larvae and, in the field, the presence of the invasive species was associated with a ten-fold increase in the post-settlement mortality of the native species, as well as an initial reduction of growth in the native. Our results suggest that larvae of the native species avoid settling near the invasive species due to reduced post-settlement survival in its presence. Overall, we found that invasive species can have complex and pervasive effects (both lethal and non-lethal) across the early life-history stages of the native species, which are likely to result in its displacement and to facilitate further invasion.

Assessing the Value of Post-processed State-of-the-art Long-term Weather Forecast Ensembles within An Integrated Agronomic Modelling Framework

NASA Astrophysics Data System (ADS)

LI, Y.; Castelletti, A.; Giuliani, M.

2014-12-01

Over recent years, long-term climate forecast from global circulation models (GCMs) has been demonstrated to show increasing skills over the climatology, thanks to the advances in the modelling of coupled ocean-atmosphere dynamics. Improved information from long-term forecast is supposed to be a valuable support to farmers in optimizing farming operations (e.g. crop choice, cropping time) and for more effectively coping with the adverse impacts of climate variability. Yet, evaluating how valuable this information can be is not straightforward and farmers' response must be taken into consideration. Indeed, while long-range forecast are traditionally evaluated in terms of accuracy by comparison of hindcast and observed values, in the context of agricultural systems, potentially useful forecast information should alter the stakeholders' expectation, modify their decisions and ultimately have an impact on their annual benefit. Therefore, it is more desirable to assess the value of those long-term forecasts via decision-making models so as to extract direct indication of probable decision outcomes from farmers, i.e. from an end-to-end perspective. In this work, we evaluate the operational value of thirteen state-of-the-art long-range forecast ensembles against climatology forecast and subjective prediction (i.e. past year climate and historical average) within an integrated agronomic modeling framework embedding an implicit model of farmers' behavior. Collected ensemble datasets are bias-corrected and downscaled using a stochastic weather generator, in order to address the mismatch of the spatio-temporal scale between forecast data from GCMs and distributed crop simulation model. The agronomic model is first simulated using the forecast information (ex-ante), followed by a second run with actual climate (ex-post). Multi-year simulations are performed to account for climate variability and the value of the different climate forecast is evaluated against the perfect

9 CFR 93.912 - Import permits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... CONVEYANCE AND SHIPPING CONTAINERS Aquatic Animal Species General Provisions for Vhs-Regulated Fish Species... and Plant Health Inspection Service, Veterinary Services, National Center for Import and Export, 4700...

9 CFR 93.912 - Import permits.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... CONVEYANCE AND SHIPPING CONTAINERS Aquatic Animal Species General Provisions for Vhs-Regulated Fish Species... and Plant Health Inspection Service, Veterinary Services, National Center for Import and Export, 4700...

Species richness at the guild level: effects of species pool and local environmental conditions on stream macroinvertebrate communities.

PubMed

Grönroos, Mira; Heino, Jani

2012-05-01

1. A fundamental question in ecology is which factors determine species richness. Here, we studied the relative importance of regional species pool and local environmental characteristics in determining local species richness (LSR). Typically, this question has been studied using whole communities or a certain taxonomic group, although including species with widely varying biological traits in the same analysis may hinder the detection of ecologically meaningful patterns. 2. We studied the question above for whole stream macroinvertebrate community and within functional feeding guilds. We defined the local scale as a riffle site and the regional scale (i.e. representing the regional species pool) as a stream. Such intermediate-sized regional scale is rarely studied in this context. 3. We sampled altogether 100 sites, ten riffles (local scale) in each of ten streams (regional scale). We used the local-regional richness regression plots to study the overall effect of regional species pool on LSR. Variation partitioning was used to determine the relative importance of regional species pool and local environmental conditions for species richness. 4. The local-regional richness relationship was mainly linear, suggesting strong species pool effects. Only one guild showed some signs of curvilinearity. However, variation partitioning showed that local environmental characteristics accounted for a larger fraction of variance in LSR than regional species pool. Also, the relative importance of the fractions differed between the whole community and guilds, as well as among guilds. 5. This study indicates that the importance of the local and regional processes may vary depending on feeding guild and trophic level. We conclude that both the size of the regional species pool and local habitat characteristics are important in determining LSR of stream macroinvertebrates. Our results are in agreement with recent large-scale studies conducted in highly different study

Commercially important species associated with horse mussel (Modiolus modiolus) biogenic reefs: A priority habitat for nature conservation and fisheries benefits.

PubMed

Kent, Flora E A; Mair, James M; Newton, Jason; Lindenbaum, Charles; Porter, Joanne S; Sanderson, William G

2017-05-15

Horse mussel reefs (Modiolus modiolus) are biodiversity hotspots afforded protection by Marine Protected Areas (MPAs) in the NE Atlantic. In this study, horse mussel reefs, cobble habitats and sandy habitats were assessed using underwater visual census and drop-down video techniques in three UK regions. Megafauna were enumerated, differences in community composition and individual species abundances were analysed. Samples of conspicuous megafauna were also collected from horse mussel reefs in Orkney for stable isotope analysis. Communities of conspicuous megafauna were different between horse mussel habitats and other habitats throughout their range. Three commercially important species: whelks (Buccinum undatum), queen scallops (Aequipecten opercularis) and spider crabs (Maja brachydactyla) were significantly more abundant (by as much as 20 times) on horse mussel reefs than elsewhere. Isotopic analysis provided insights into their trophic relationship with the horse mussel reef. Protection of M. modiolus habitat can achieve biodiversity conservation objectives whilst benefiting fisheries also. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative genomic and transcriptomic analysis of selected fatty acid biosynthesis genes and CNL disease resistance genes in oil palm.

PubMed

Rosli, Rozana; Amiruddin, Nadzirah; Ab Halim, Mohd Amin; Chan, Pek-Lan; Chan, Kuang-Lim; Azizi, Norazah; Morris, Priscilla E; Leslie Low, Eng-Ti; Ong-Abdullah, Meilina; Sambanthamurthi, Ravigadevi; Singh, Rajinder; Murphy, Denis J

2018-01-01

Comparative genomics and transcriptomic analyses were performed on two agronomically important groups of genes from oil palm versus other major crop species and the model organism, Arabidopsis thaliana. The first analysis was of two gene families with key roles in regulation of oil quality and in particular the accumulation of oleic acid, namely stearoyl ACP desaturases (SAD) and acyl-acyl carrier protein (ACP) thioesterases (FAT). In both cases, these were found to be large gene families with complex expression profiles across a wide range of tissue types and developmental stages. The detailed classification of the oil palm SAD and FAT genes has enabled the updating of the latest version of the oil palm gene model. The second analysis focused on disease resistance (R) genes in order to elucidate possible candidates for breeding of pathogen tolerance/resistance. Ortholog analysis showed that 141 out of the 210 putative oil palm R genes had homologs in banana and rice. These genes formed 37 clusters with 634 orthologous genes. Classification of the 141 oil palm R genes showed that the genes belong to the Kinase (7), CNL (95), MLO-like (8), RLK (3) and Others (28) categories. The CNL R genes formed eight clusters. Expression data for selected R genes also identified potential candidates for breeding of disease resistance traits. Furthermore, these findings can provide information about the species evolution as well as the identification of agronomically important genes in oil palm and other major crops.

Comparative genomic and transcriptomic analysis of selected fatty acid biosynthesis genes and CNL disease resistance genes in oil palm

PubMed Central

Rosli, Rozana; Amiruddin, Nadzirah; Ab Halim, Mohd Amin; Chan, Pek-Lan; Chan, Kuang-Lim; Azizi, Norazah; Morris, Priscilla E.; Leslie Low, Eng-Ti; Ong-Abdullah, Meilina; Sambanthamurthi, Ravigadevi; Singh, Rajinder

2018-01-01

Comparative genomics and transcriptomic analyses were performed on two agronomically important groups of genes from oil palm versus other major crop species and the model organism, Arabidopsis thaliana. The first analysis was of two gene families with key roles in regulation of oil quality and in particular the accumulation of oleic acid, namely stearoyl ACP desaturases (SAD) and acyl-acyl carrier protein (ACP) thioesterases (FAT). In both cases, these were found to be large gene families with complex expression profiles across a wide range of tissue types and developmental stages. The detailed classification of the oil palm SAD and FAT genes has enabled the updating of the latest version of the oil palm gene model. The second analysis focused on disease resistance (R) genes in order to elucidate possible candidates for breeding of pathogen tolerance/resistance. Ortholog analysis showed that 141 out of the 210 putative oil palm R genes had homologs in banana and rice. These genes formed 37 clusters with 634 orthologous genes. Classification of the 141 oil palm R genes showed that the genes belong to the Kinase (7), CNL (95), MLO-like (8), RLK (3) and Others (28) categories. The CNL R genes formed eight clusters. Expression data for selected R genes also identified potential candidates for breeding of disease resistance traits. Furthermore, these findings can provide information about the species evolution as well as the identification of agronomically important genes in oil palm and other major crops. PMID:29672525

Collection and evaluation of Helianthus verticillatus, an endemic sunflower of the Southeast US

USDA-ARS?s Scientific Manuscript database

The genus Helianthus comprises 51 species, 14 annual and 37 perennial, and all native to North America. The narrow genetic base of cultivated sunflower has been broadened by the infusion of genes from the wild species, which have provided a continued source of desirable agronomic traits. Whorled sun...

The Potential Role of Neglected and Underutilised Crop Species as Future Crops under Water Scarce Conditions in Sub-Saharan Africa

PubMed Central

Chivenge, Pauline; Mabhaudhi, Tafadzwanashe; Modi, Albert T.; Mafongoya, Paramu

2015-01-01

Modern agricultural systems that promote cultivation of a very limited number of crop species have relegated indigenous crops to the status of neglected and underutilised crop species (NUCS). The complex interactions of water scarcity associated with climate change and variability in sub-Saharan Africa (SSA), and population pressure require innovative strategies to address food insecurity and undernourishment. Current research efforts have identified NUCS as having potential to reduce food and nutrition insecurity, particularly for resource poor households in SSA. This is because of their adaptability to low input agricultural systems and nutritional composition. However, what is required to promote NUCS is scientific research including agronomy, breeding, post-harvest handling and value addition, and linking farmers to markets. Among the essential knowledge base is reliable information about water utilisation by NUCS with potential for commercialisation. This commentary identifies and characterises NUCS with agronomic potential in SSA, especially in the semi-arid areas taking into consideration inter alia: (i) what can grow under water-scarce conditions, (ii) water requirements, and (iii) water productivity. Several representative leafy vegetables, tuber crops, cereal crops and grain legumes were identified as fitting the NUCS category. Agro-biodiversity remains essential for sustainable agriculture. PMID:26016431

Agronomic Effectiveness of Granulated and Powdered P-Exchanged Mg-Al LDH Relative to Struvite and MAP.

PubMed

Everaert, Maarten; Degryse, Fien; McLaughlin, Mike J; De Vos, Dirk; Smolders, Erik

2017-08-16

Layered double hydroxides (LDHs) used to recover P from wastewater have recently been proposed as new slow-release fertilizers. Here, the use of P-exchanged Mg-Al LDHs as powdered or granulated fertilizer is explored and compared with monoammonium phosphate (MAP), a fully water-soluble fertilizer, and with struvite, a recycled phosphate fertilizer with lower solubility. First, these three fertilizers were compared in a 100-day incubation experiment using P diffusion visualization and chemical analysis to assess P release from either granules or powdered fertilizer in three different soils. By the end of the incubation, 74-90% of P remained within the LDH granule, confirming a slow release. Second, a pot experiment was performed with wheat (Triticum aestivum) in an acid and a calcareous soil. The granular treatment resulted in a considerably higher P uptake for MAP compared to LDH and struvite. For the powder treatments, the P uptake was less than for granular MAP and was largely unaffected by the chemical form. The LDHs and struvite showed a lower agronomic effectiveness than granular MAP, but the benefits of their use in P recycling, potential residual value, and environmental benefits may render these slow-release fertilizers attractive.

Assessing Species Boundaries Using Multilocus Species Delimitation in a Morphologically Conserved Group of Neotropical Freshwater Fishes, the Poecilia sphenops Species Complex (Poeciliidae)

PubMed Central

Bagley, Justin C.; Alda, Fernando; Breitman, M. Florencia; Bermingham, Eldredge; van den Berghe, Eric P.; Johnson, Jerald B.

2015-01-01

Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including ‘non-adaptive radiations’ containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci) from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial ‘major-lineages’ diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively) 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the importance of

Assessing species boundaries using multilocus species delimitation in a morphologically conserved group of neotropical freshwater fishes, the Poecilia sphenops species complex (Poeciliidae).

PubMed

Bagley, Justin C; Alda, Fernando; Breitman, M Florencia; Bermingham, Eldredge; van den Berghe, Eric P; Johnson, Jerald B

2015-01-01

Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including 'non-adaptive radiations' containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci) from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial 'major-lineages' diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively) 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the importance of testing for

Tropical legume crop rotation and nitrogen fertilizer effects on agronomic and nitrogen efficiency of rice.

PubMed

Rahman, Motior M; Islam, Aminul M; Azirun, Sofian M; Boyce, Amru N

2014-01-01

Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m(-2) preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m(-2). No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE), nitrogen recovery efficiency (NRE), N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4 g N m(-2) achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13-23% higher grain yield than rice after fallow rotation with 8 g N m(-2). The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 g N m(-2) can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 g N m(-2). The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility.

Seasonal variations in diet composition, diet breadth and dietary overlap between three commercially important fish species within a flood-pulse system: The Tonle Sap Lake (Cambodia).

PubMed

Heng, Kong; Chevalier, Mathieu; Lek, Sovan; Laffaille, Pascal

2018-01-01

Tropical lakes and their associated floodplain habitats are dynamic habitat mosaics strongly influenced by seasonal variations in hydrologic conditions. In flood-pulse systems, water level oscillations directly influence the connectivity to floodplain habitats for fish. Here, we aimed to investigate whether seasonal changes in the water level of a flood-pulse system (the Tonle Sap Lake, Cambodia) differentially affect diet breadth and dietary overlap of three common and commercially important fish species (Anabas testudineus, Boesemania microplepis and Notopterus notopterus) presenting important differences in their life-cycle (e.g. seasonal migration). For this purpose, the three fish species were sampled at four locations spread over the lake and their stomach contents extracted for analyses. Dietary differences were investigated across seasons regarding the diet composition and diet breadth of each species as well as the amount of dietary overlap between species. We found that the proportion of empty stomachs changed similarly across seasons for the three species, thus suggesting that ecological differences between species are not sufficient to outweigh the effect of seasonal variations in resource abundance. In contrast, changes in diet composition were species-specific and can be explained by ecological and behavioral differences between species. Diet breadth differed between species in all seasons, except during the wet season, and tended to be higher during the dry season when dietary overlap was the lowest. These variations likely result from changes in the diversity and amount of resources and may lead to habitat use shifts with potential implications for competitive interactions. In particular, increasing connectivity to floodplain habitats may reduce the competitive pressure during the wet season, while resource scarcity during the dry season may constrain individuals to diversify their diet to avoid competition. Overall, our results suggest a

Strong thermal acclimation of photosynthesis in tropical and temperate wet-forest tree species: the importance of altered Rubisco content.

PubMed

Scafaro, Andrew P; Xiang, Shuang; Long, Benedict M; Bahar, Nur H A; Weerasinghe, Lasantha K; Creek, Danielle; Evans, John R; Reich, Peter B; Atkin, Owen K

2017-07-01

Understanding of the extent of acclimation of light-saturated net photosynthesis (A n ) to temperature (T), and associated underlying mechanisms, remains limited. This is a key knowledge gap given the importance of thermal acclimation for plant functioning, both under current and future higher temperatures, limiting the accuracy and realism of Earth system model (ESM) predictions. Given this, we analysed and modelled T-dependent changes in photosynthetic capacity in 10 wet-forest tree species: six from temperate forests and four from tropical forests. Temperate and tropical species were each acclimated to three daytime growth temperatures (T growth ): temperate - 15, 20 and 25 °C; tropical - 25, 30 and 35 °C. CO 2 response curves of A n were used to model maximal rates of RuBP (ribulose-1,5-bisphosphate) carboxylation (V cmax ) and electron transport (J max ) at each treatment's respective T growth and at a common measurement T (25 °C). SDS-PAGE gels were used to determine abundance of the CO 2 -fixing enzyme, Rubisco. Leaf chlorophyll, nitrogen (N) and mass per unit leaf area (LMA) were also determined. For all species and T growth , A n at current atmospheric CO 2 partial pressure was Rubisco-limited. Across all species, LMA decreased with increasing T growth . Similarly, area-based rates of V cmax at a measurement T of 25 °C (V cmax 25 ) linearly declined with increasing T growth , linked to a concomitant decline in total leaf protein per unit leaf area and Rubisco as a percentage of leaf N. The decline in Rubisco constrained V cmax and A n for leaves developed at higher T growth and resulted in poor predictions of photosynthesis by currently widely used models that do not account for T growth -mediated changes in Rubisco abundance that underpin the thermal acclimation response of photosynthesis in wet-forest tree species. A new model is proposed that accounts for the effect of T growth -mediated declines in V cmax 25 on A n , complementing current

Importance of well-designed monitoring programs for the conservation of endangered species: case study of the Snail Kite

USGS Publications Warehouse

Martin, J.; Kitchens, W.M.; Hines, J.E.

2007-01-01

Monitoring natural populations is often a necessary step to establish the conservation status of species and to help improve management decisions. Nevertheless, many monitoring programs do not effectively address primary sources of variability in monitoring data, which ultimately may limit the utility of monitoring in identifying declines and improving management. To illustrate the importance of taking into account detectability and spatial variation, we used a recently proposed estimator of abundance (superpopulation estimator) to estimate population size of and number of young produced by the Snail Kite (Rostrhamus sociabilis plumbeus) in Florida. During the last decade, primary recovery targets set by the U.S. Fish and Wildlife Service for the Snail Kite that were based on deficient monitoring programs (i.e., uncorrected counts) were close to being met (by simply increasing search effort during count surveys). During that same period, the Snail Kite population declined dramatically (by 55% from 1997 to 2005) and the number of young decreased by 70% between 1992?1998 and 1999?2005. Our results provide a strong practical case in favor of the argument that investing a sufficient amount of time and resources into designing and implementing monitoring programs that carefully address detectability and spatial variation is critical for the conservation of endangered species.

Rare species contribute disproportionately to the functional structure of species assemblages

PubMed Central

Zuanon, Jansen; Williams, Stephen E.; Baraloto, Christopher; Mendonça, Fernando P.

2016-01-01

There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versus commonness, combining local abundance, geographical range, and habitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions. PMID:27053754

Ticks imported to Europe with exotic reptiles.

PubMed

Mihalca, Andrei Daniel

2015-09-30

It is known that traded exotic animals carry with them an immense number of associated symbionts, including parasites. Reptiles are no exception. Most of the imported reptiles originate from tropical countries and their possibility to carry potentially dangerous pathogens is high. According to CITES, Europe is currently the main reptile importer in the world. Despite this, there is no review or analysis available for the risk related to the importation of tick-borne diseases with traded reptile to the EU. The main aim of the manuscript is to provide a review on the available literature on ticks introduced to and exchanged between European countries via the live reptile trade. So far, the published reports of ticks imported on reptiles are limited to few European countries: Italy, Poland, Spain, Netherlands, Belgium, Slovenia and UK. The following species have been reported: Hyalomma aegyptium, Amblyomma dissimile, Amblyomma exornatum, Amblyomma flavomaculatum, Amblyomma fuscolineatum, Amblyomma latum, Amblyomma quadricavum, Amblyomma marmoreum, Amblyomma nuttalli, Amblyomma sparsum, Amblyomma sphenodonti, Amblyomma transversale and Amblyomma varanense. The majority of species are of African origin, followed by American and Asian species. All groups of reptiles (chelonians, snakes, lizards, crocodiles, tuataras) were involved. However, it seems that certain groups (i.e. tortoises of genus Testudo, monitor lizards of genus Varanus, snakes of genus Python) are more important as host for imported ticks, but this may be related to higher levels of international trade. Even fewer are the reports of tick-borne pathogens associated with imported reptile ticks. Despite the diversity of tick species reported on imported reptiles, the situations of truly invasive species are atypical and are limited in natural environments to maximum two cases where H. aegyptium was involved. Otherwise, the risk associated with reptile trade for introduction of invasive tick to Europe is low

Identification of Shewanella baltica as the most important H2S-producing species during iced storage of Danish marine fish.

PubMed

Fonnesbech Vogel, Birte; Venkateswaran, Kasthuri; Satomi, Masataka; Gram, Lone

2005-11-01

Shewanella putrefaciens has been considered the main spoilage bacteria of low-temperature stored marine seafood. However, psychrotropic Shewanella have been reclassified during recent years, and the purpose of the present study was to determine whether any of the new Shewanella species are important in fish spoilage. More than 500 H2S-producing strains were isolated from iced stored marine fish (cod, plaice, and flounder) caught in the Baltic Sea during winter or summer time. All strains were identified as Shewanella species by phenotypic tests. Different Shewanella species were present on newly caught fish. During the warm summer months the mesophilic human pathogenic S. algae dominated the H2S-producing bacterial population. After iced storage, a shift in the Shewanella species was found, and most of the H2S-producing strains were identified as S. baltica. The 16S rRNA gene sequence analysis confirmed the identification of these two major groups. Several isolates could only be identified to the genus Shewanella level and were separated into two subgroups with low (44%) and high (47%) G+C mol%. The low G+C% group was isolated during winter months, whereas the high G+C% group was isolated on fish caught during summer and only during the first few days of iced storage. Phenotypically, these strains were different from the type strains of S. putrefaciens, S. oneidensis, S. colwelliana, and S. affinis, but the high G+C% group clustered close to S. colwelliana by 16S rRNA gene sequence comparison. The low G+C% group may constitute a new species. S. baltica, and the low G+C% group of Shewanella spp. strains grew well in cod juice at 0 degrees C, but three high G+C Shewanella spp. were unable to grow at 0 degrees C. In conclusion, the spoilage reactions of iced Danish marine fish remain unchanged (i.e., trimethylamine-N-oxide reduction and H2S production); however, the main H2S-producing organism was identified as S. baltica.

Predicting the impacts of climate change on animal distributions: the importance of local adaptation and species' traits

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

HELLMANN, J. J.; LOBO, N. F.

2011-12-20

The geographic range limits of many species are strongly affected by climate and are expected to change under global warming. For species that are able to track changing climate over broad geographic areas, we expect to see shifts in species distributions toward the poles and away from the equator. A number of ecological and evolutionary factors, however, could restrict this shifting or redistribution under climate change. These factors include restricted habitat availability, restricted capacity for or barriers to movement, or reduced abundance of colonists due the perturbation effect of climate change. This research project examined the last of these constraintsmore » - that climate change could perturb local conditions to which populations are adapted, reducing the likelihood that a species will shift its distribution by diminishing the number of potential colonists. In the most extreme cases, species ranges could collapse over a broad geographic area with no poleward migration and an increased risk of species extinction. Changes in individual species ranges are the processes that drive larger phenomena such as changes in land cover, ecosystem type, and even changes in carbon cycling. For example, consider the poleward range shift and population outbreaks of the mountain pine beetle that has decimated millions of acres of Douglas fir trees in the western US and Canada. Standing dead trees cause forest fires and release vast quantities of carbon to the atmosphere. The beetle likely shifted its range because it is not locally adapted across its range, and it appears to be limited by winter low temperatures that have steadily increased in the last decades. To understand range and abundance changes like the pine beetle, we must reveal the extent of adaptive variation across species ranges - and the physiological basis of that adaptation - to know if other species will change as readily as the pine beetle. Ecologists tend to assume that range shifts are the

75 FR 78974 - Endangered Species

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-17

...-XA086 Endangered Species AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... the Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.) and the regulations governing the taking, importing, and exporting of endangered and threatened species (50 CFR 222-226). Permit...

50 CFR 15.31 - Criteria for including species in the approved list for captive-bred species.

Code of Federal Regulations, 2012 CFR

2012-10-01

... approved list for captive-bred species. 15.31 Section 15.31 Wildlife and Fisheries UNITED STATES FISH AND..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS WILD BIRD CONSERVATION ACT Approved List of Species Listed... captive-bred species. The Director will periodically review the list of captive-bred exotic bird species...

50 CFR 15.31 - Criteria for including species in the approved list for captive-bred species.

Code of Federal Regulations, 2014 CFR

2014-10-01

... approved list for captive-bred species. 15.31 Section 15.31 Wildlife and Fisheries UNITED STATES FISH AND..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS WILD BIRD CONSERVATION ACT Approved List of Species Listed... captive-bred species. The Director will periodically review the list of captive-bred exotic bird species...