Sample records for causing yield losses

  1. Understanding yield loss and pathogen biology to improve disease management: Stagonospora nodorum blotch - a case study in wheat

    USDA-ARS?s Scientific Manuscript database

    The estimated potential yield losses caused by plant pathogens are up to 16% globally, and most research in plant pathology aims to reduce yield loss in crops directly or indirectly. Yield losses caused by a certain disease depend not only on disease severity, but also on weather factors, the pathog...

  2. Primary and Secondary Yield Losses Caused by Pests and Diseases: Assessment and Modeling in Coffee

    PubMed Central

    Gary, Christian; Tixier, Philippe; Lechevallier, Esther

    2017-01-01

    The assessment of crop yield losses is needed for the improvement of production systems that contribute to the incomes of rural families and food security worldwide. However, efforts to quantify yield losses and identify their causes are still limited, especially for perennial crops. Our objectives were to quantify primary yield losses (incurred in the current year of production) and secondary yield losses (resulting from negative impacts of the previous year) of coffee due to pests and diseases, and to identify the most important predictors of coffee yields and yield losses. We established an experimental coffee parcel with full-sun exposure that consisted of six treatments, which were defined as different sequences of pesticide applications. The trial lasted three years (2013–2015) and yield components, dead productive branches, and foliar pests and diseases were assessed as predictors of yield. First, we calculated yield losses by comparing actual yields of specific treatments with the estimated attainable yield obtained in plots which always had chemical protection. Second, we used structural equation modeling to identify the most important predictors. Results showed that pests and diseases led to high primary yield losses (26%) and even higher secondary yield losses (38%). We identified the fruiting nodes and the dead productive branches as the most important and useful predictors of yields and yield losses. These predictors could be added in existing mechanistic models of coffee, or can be used to develop new linear mixed models to estimate yield losses. Estimated yield losses can then be related to production factors to identify corrective actions that farmers can implement to reduce losses. The experimental and modeling approaches of this study could also be applied in other perennial crops to assess yield losses. PMID:28046054

  3. Primary and Secondary Yield Losses Caused by Pests and Diseases: Assessment and Modeling in Coffee.

    PubMed

    Cerda, Rolando; Avelino, Jacques; Gary, Christian; Tixier, Philippe; Lechevallier, Esther; Allinne, Clémentine

    2017-01-01

    The assessment of crop yield losses is needed for the improvement of production systems that contribute to the incomes of rural families and food security worldwide. However, efforts to quantify yield losses and identify their causes are still limited, especially for perennial crops. Our objectives were to quantify primary yield losses (incurred in the current year of production) and secondary yield losses (resulting from negative impacts of the previous year) of coffee due to pests and diseases, and to identify the most important predictors of coffee yields and yield losses. We established an experimental coffee parcel with full-sun exposure that consisted of six treatments, which were defined as different sequences of pesticide applications. The trial lasted three years (2013-2015) and yield components, dead productive branches, and foliar pests and diseases were assessed as predictors of yield. First, we calculated yield losses by comparing actual yields of specific treatments with the estimated attainable yield obtained in plots which always had chemical protection. Second, we used structural equation modeling to identify the most important predictors. Results showed that pests and diseases led to high primary yield losses (26%) and even higher secondary yield losses (38%). We identified the fruiting nodes and the dead productive branches as the most important and useful predictors of yields and yield losses. These predictors could be added in existing mechanistic models of coffee, or can be used to develop new linear mixed models to estimate yield losses. Estimated yield losses can then be related to production factors to identify corrective actions that farmers can implement to reduce losses. The experimental and modeling approaches of this study could also be applied in other perennial crops to assess yield losses.

  4. Fault tree analysis for data-loss in long-term monitoring networks.

    PubMed

    Dirksen, J; ten Veldhuis, J A E; Schilperoort, R P S

    2009-01-01

    Prevention of data-loss is an important aspect in the design as well as the operational phase of monitoring networks since data-loss can seriously limit intended information yield. In the literature limited attention has been paid to the origin of unreliable or doubtful data from monitoring networks. Better understanding of causes of data-loss points out effective solutions to increase data yield. This paper introduces FTA as a diagnostic tool to systematically deduce causes of data-loss in long-term monitoring networks in urban drainage systems. In order to illustrate the effectiveness of FTA, a fault tree is developed for a monitoring network and FTA is applied to analyze the data yield of a UV/VIS submersible spectrophotometer. Although some of the causes of data-loss cannot be recovered because the historical database of metadata has been updated infrequently, the example points out that FTA still is a powerful tool to analyze the causes of data-loss and provides useful information on effective data-loss prevention.

  5. Interactive effects of pests increase seed yield.

    PubMed

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

    2016-04-01

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

  6. Ozone-Induced Rice Grain Yield Loss Is Triggered via a Change in Panicle Morphology That Is Controlled by ABERRANT PANICLE ORGANIZATION 1 Gene

    PubMed Central

    Tsukahara, Keita; Sawada, Hiroko; Kohno, Yoshihisa; Matsuura, Takakazu; Mori, Izumi C.; Terao, Tomio; Ioki, Motohide; Tamaoki, Masanori

    2015-01-01

    Rice grain yield is predicted to decrease in the future because of an increase in tropospheric ozone concentration. However, the underlying mechanisms are unclear. Here, we investigated the responses to ozone of two rice (Oryza Sativa L.) cultivars, Sasanishiki and Habataki. Sasanishiki showed ozone-induced leaf injury, but no grain yield loss. By contrast, Habataki showed grain yield loss with minimal leaf injury. A QTL associated with grain yield loss caused by ozone was identified in Sasanishiki/Habataki chromosome segment substitution lines and included the ABERRANT PANICLE ORGANIZATION 1 (APO1) gene. The Habataki allele of the APO1 locus in a near-isogenic line also resulted in grain yield loss upon ozone exposure, suggesting APO1 involvement in ozone-induced yield loss. Only a few differences in the APO1 amino acid sequences were detected between the cultivars, but the APO1 transcript level was oppositely regulated by ozone exposure: i.e., it increased in Sasanishiki and decreased in Habataki. Interestingly, the levels of some phytohormones (jasmonic acid, jasmonoyl-L-isoleucine, and abscisic acid) known to be involved in attenuation of ozone-induced leaf injury tended to decrease in Sasanishiki but to increase in Habataki upon ozone exposure. These data indicate that ozone-induced grain yield loss in Habataki is caused by a reduction in the APO1 transcript level through an increase in the levels of phytohormones that reduce leaf damage. PMID:25923431

  7. An economic assessment of the health effects and crop yield losses caused by air pollution in mainland China.

    PubMed

    Miao, Weijie; Huang, Xin; Song, Yu

    2017-06-01

    Air pollution is severe in China, and pollutants such as PM 2.5 and surface O 3 may cause major damage to human health and crops, respectively. Few studies have considered the health effects of PM 2.5 or the loss of crop yields due to surface O 3 using model-simulated air pollution data in China. We used gridded outputs from the WRF-Chem model, high resolution population data, and crop yield data to evaluate the effects on human health and crop yield in mainland China. Our results showed that outdoor PM 2.5 pollution was responsible for 1.70-1.99 million cases of all-cause mortality in 2006. The economic costs of these health effects were estimated to be 151.1-176.9 billion USD, of which 90% were attributed to mortality. The estimated crop yield losses for wheat, rice, maize, and soybean were approximately 9, 4.6, 0.44, and 0.34 million tons, respectively, resulting in economic losses of 3.4 billion USD. The total economic losses due to ambient air pollution were estimated to be 154.5-180.3 billion USD, accounting for approximately 5.7%-6.6% of the total GDP of China in 2006. Our results show that both population health and staple crop yields in China have been significantly affected by exposure to air pollution. Measures should be taken to reduce emissions, improve air quality, and mitigate the economic loss. Copyright © 2016. Published by Elsevier B.V.

  8. Causes and implications of the unforeseen 2016 extreme yield loss in the breadbasket of France.

    PubMed

    Ben-Ari, Tamara; Boé, Julien; Ciais, Philippe; Lecerf, Remi; Van der Velde, Marijn; Makowski, David

    2018-04-24

    In 2016, France, one of the leading wheat-producing and wheat-exporting regions in the world suffered its most extreme yield loss in over half a century. Yet, yield forecasting systems failed to anticipate this event. We show that this unprecedented event is a new type of compound extreme with a conjunction of abnormally warm temperatures in late autumn and abnormally wet conditions in the following spring. A binomial logistic regression accounting for fall and spring conditions is able to capture key yield loss events since 1959. Based on climate projections, we show that the conditions that led to the 2016 wheat yield loss are projected to become more frequent in the future. The increased likelihood of such compound extreme events poses a challenge: farming systems and yield forecasting systems, which often support them, must adapt.

  9. Assessing the impacts of current and future concentrations of surface ozone on crop yield with meta-analysis

    NASA Astrophysics Data System (ADS)

    Feng, Zhaozhong; Kobayashi, Kazuhiko

    Meta-analysis was conducted to quantitatively assess the effects of rising ozone concentrations ([O 3]) on yield and yield components of major food crops: potato, barley, wheat, rice, bean and soybean in 406 experimental observations. Yield loss of the crops under current and future [O 3] was expressed relative to the yield under base [O 3] (≤26 ppb). With potato, current [O 3] (31-50 ppb) reduced the yield by 5.3%, and it reduced the yield of barley, wheat and rice by 8.9%, 9.7% and 17.5%, respectively. In bean and soybean, the yield losses were 19.0% and 7.7%, respectively. Compared with yield loss at current [O 3], future [O 3] (51-75 ppb) drove a further 10% loss in yield of soybean, wheat and rice, and 20% loss in bean. Mass of individual grain, seed, or tuber was often the major cause of the yield loss at current and future [O 3], whereas other yield components also contributed to the yield loss in some cases. No significant difference was found between the responses in crops grown in pots and those in the ground for any yield parameters. The ameliorating effect of elevated [CO 2] was significant in the yields of wheat and potato, and the individual grain weight in wheat exposed to future [O 3]. These findings confirm the rising [O 3] as a threat to food security for the growing global population in this century.

  10. Global assessment of nitrogen losses and trade-offs with yields from major crop cultivations.

    PubMed

    Liu, Wenfeng; Yang, Hong; Liu, Junguo; Azevedo, Ligia B; Wang, Xiuying; Xu, Zongxue; Abbaspour, Karim C; Schulin, Rainer

    2016-12-01

    Agricultural application of reactive nitrogen (N) for fertilization is a cause of massive negative environmental problems on a global scale. However, spatially explicit and crop-specific information on global N losses into the environment and knowledge of trade-offs between N losses and crop yields are largely lacking. We use a crop growth model, Python-based Environmental Policy Integrated Climate (PEPIC), to determine global N losses from three major food crops: maize, rice, and wheat. Simulated total N losses into the environment (including water and atmosphere) are 44TgNyr -1 . Two thirds of these, or 29TgNyr -1 , are losses to water alone. Rice accounts for the highest N losses, followed by wheat and maize. The N loss intensity (NLI), defined as N losses per unit of yield, is used to address trade-offs between N losses and crop yields. The NLI presents high variation among different countries, indicating diverse N losses to produce the same amount of yields. Simulations of mitigation scenarios indicate that redistributing global N inputs and improving N management could significantly abate N losses and at the same time even increase yields without any additional total N inputs. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Screening soybean germplasm and commerical varieties for resistance to Phomopsis seed decay: results from 2012 trials

    USDA-ARS?s Scientific Manuscript database

    Soybean Phomopsis seed decay (PSD) causes poor seed quality and suppresses yield in most soybean production areas of the United States. In 2009, PSD caused a yield loss of over 12 million bushels in 16 southern states. The disease is primarily caused by Phomopsis longicolla along with other Phomopsi...

  12. Reaction of maturity group IV soybean plant introductions to Phomopsis Seed Decay in Arkansas Mississippi and Missouri 2009

    USDA-ARS?s Scientific Manuscript database

    Soybean Phomopsis seed decay (PSD) causes poor seed quality and suppresses yield in most of soybean-growing states in United States. In 2009, PSD caused over 12 million bushel yield loss in 16 southern states. The disease is primarily caused by Phomopsis longicolla along with other Phomopsis and Dia...

  13. Identification of soybean accessions with resistance to Phomopsis seed decay: joint effort from USDA and university scientists

    USDA-ARS?s Scientific Manuscript database

    Soybean Phomopsis seed decay (PSD) is primarily caused by Phomopsis longicolla along with other Phomopsis and Diaporthe spp. This disease causes poor seed quality and suppresses yield in most soybean-growing states in the United States. In 2009, PSD caused yield loss of over 12 million bushels in 16...

  14. Maize proximate composition and physical properties correlations to dry-grind ethanol concentrations

    USDA-ARS?s Scientific Manuscript database

    Dry grind ethanol plants incur economic losses due to seasonal variations in ethanol yields. One possible cause associated with ethanol yield variability is incoming grain quality. There is little published information on factors causing variation in dry grind ethanol concentrations. The objective o...

  15. Remote-sensing-based rapid assessment of flood crop loss to support USDA flooding decision-making

    NASA Astrophysics Data System (ADS)

    Di, L.; Yu, G.; Yang, Z.; Hipple, J.; Shrestha, R.

    2016-12-01

    Floods often cause significant crop loss in the United States. Timely and objective assessment of flood-related crop loss is very important for crop monitoring and risk management in agricultural and disaster-related decision-making in USDA. Among all flood-related information, crop yield loss is particularly important. Decision on proper mitigation, relief, and monetary compensation relies on it. Currently USDA mostly relies on field surveys to obtain crop loss information and compensate farmers' loss claim. Such methods are expensive, labor intensive, and time consumptive, especially for a large flood that affects a large geographic area. Recent studies have demonstrated that Earth observation (EO) data are useful in post-flood crop loss assessment for a large geographic area objectively, timely, accurately, and cost effectively. There are three stages of flood damage assessment, including rapid assessment, early recovery assessment, and in-depth assessment. EO-based flood assessment methods currently rely on the time-series of vegetation index to assess the yield loss. Such methods are suitable for in-depth assessment but are less suitable for rapid assessment since the after-flood vegetation index time series is not available. This presentation presents a new EO-based method for the rapid assessment of crop yield loss immediately after a flood event to support the USDA flood decision making. The method is based on the historic records of flood severity, flood duration, flood date, crop type, EO-based both before- and immediate-after-flood crop conditions, and corresponding crop yield loss. It hypotheses that a flood of same severity occurring at the same pheonological stage of a crop will cause the similar damage to the crop yield regardless the flood years. With this hypothesis, a regression-based rapid assessment algorithm can be developed by learning from historic records of flood events and corresponding crop yield loss. In this study, historic records of MODIS-based flood and vegetation products and USDA/NASS crop type and crop yield data are used to train the regression-based rapid assessment algorithm. Validation of the rapid assessment algorithm indicates it can predict the yield loss at 90% accuracy, which is accurate enough to support USDA on flood-related quick response and mitigation.

  16. Population structure of Cercospora sojina collected from different soybean culitvars in Milan and Jackson Tennessee

    USDA-ARS?s Scientific Manuscript database

    Frogeye Leaf Spot (FLS) of soybean is caused by the fungal pathogen, Cercospora sojina Hara. FLS causes significant damage resulting in a yield loss of 4 to 6 Bu/Acre, mostly in the Southern U.S. Since its first report in South Carolina in 1924 it has caused significant damage resulting in a yield ...

  17. Use of Drought Index and Crop Modelling for Drought Impacts Analysis on Maize (Zea mays L.) Yield Loss in Bandung District

    NASA Astrophysics Data System (ADS)

    Kurniasih, E.; Impron; Perdinan

    2017-03-01

    Drought impacts on crop yield loss depend on drought magnitude and duration and on plant genotype at every plant growth stages when droughts occur. This research aims to assess the difference calculation results of 2 drought index methods and to study the maize yield loss variability impacted by drought magnitude and duration during maize growth stages in Bandung district, province of West Java, Indonesia. Droughts were quantified by the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI) at 1- to 3-month lags for the January1986-December 2015 period data. Maize yield responses to droughts were simulated by AquaCrop for the January 1986-May 2016 period of growing season. The analysis showed that the SPI and SPEI methods provided similar results in quantifying drought event. Droughts during maize reproductive stages caused the highest maize yield loss.

  18. Interaction of soybean and Phakopsora pachyrhizi, the cause of soybean rust

    USDA-ARS?s Scientific Manuscript database

    Soybean rust, caused by Phakopsora pachyrhizi H. Sydow & Sydow, is a major disease limiting soybean [Glycine max (L.) Merr.] production in many areas of the world. Yield losses of up to 80% were reported in experimental plots in Taiwan. Although the disease is not always yield limiting, it has the p...

  19. Integrated remote sensing imagery and two-dimensional hydraulic modeling approach for impact evaluation of flood on crop yields

    NASA Astrophysics Data System (ADS)

    Chen, Huili; Liang, Zhongyao; Liu, Yong; Liang, Qiuhua; Xie, Shuguang

    2017-10-01

    The projected frequent occurrences of extreme flood events will cause significant losses to crops and will threaten food security. To reduce the potential risk and provide support for agricultural flood management, prevention, and mitigation, it is important to account for flood damage to crop production and to understand the relationship between flood characteristics and crop losses. A quantitative and effective evaluation tool is therefore essential to explore what and how flood characteristics will affect the associated crop loss, based on accurately understanding the spatiotemporal dynamics of flood evolution and crop growth. Current evaluation methods are generally integrally or qualitatively based on statistic data or ex-post survey with less diagnosis into the process and dynamics of historical flood events. Therefore, a quantitative and spatial evaluation framework is presented in this study that integrates remote sensing imagery and hydraulic model simulation to facilitate the identification of historical flood characteristics that influence crop losses. Remote sensing imagery can capture the spatial variation of crop yields and yield losses from floods on a grid scale over large areas; however, it is incapable of providing spatial information regarding flood progress. Two-dimensional hydraulic model can simulate the dynamics of surface runoff and accomplish spatial and temporal quantification of flood characteristics on a grid scale over watersheds, i.e., flow velocity and flood duration. The methodological framework developed herein includes the following: (a) Vegetation indices for the critical period of crop growth from mid-high temporal and spatial remote sensing imagery in association with agricultural statistics data were used to develop empirical models to monitor the crop yield and evaluate yield losses from flood; (b) The two-dimensional hydraulic model coupled with the SCS-CN hydrologic model was employed to simulate the flood evolution process, with the SCS-CN model as a rainfall-runoff generator and the two-dimensional hydraulic model implementing the routing scheme for surface runoff; and (c) The spatial combination between crop yield losses and flood dynamics on a grid scale can be used to investigate the relationship between the intensity of flood characteristics and associated loss extent. The modeling framework was applied for a 50-year return period flood that occurred in Jilin province, Northeast China, which caused large agricultural losses in August 2013. The modeling results indicated that (a) the flow velocity was the most influential factor that caused spring corn, rice and soybean yield losses from extreme storm event in the mountainous regions; (b) the power function archived the best results that fit the velocity-loss relationship for mountainous areas; and (c) integrated remote sensing imagery and two-dimensional hydraulic modeling approach are helpful for evaluating the influence of historical flood event on crop production and investigating the relationship between flood characteristics and crop yield losses.

  20. 7 CFR 760.808 - General provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... harvested production does not exist; (2) The loss is due to an ineligible cause of loss or practices, soil... provisions. (a) For calculations of loss, the participant's existing unit structure will be used as the basis... (2) For NAP covered crops, part 1437 of this title. (b) County average yield for loss calculations...

  1. Economic injury level for the coffee berry borer (Coleoptera: Curculionidae: Scolytinae) using attractive traps in Brazilian coffee fields.

    PubMed

    Fernandes, F L; Picanço, M C; Campos, S O; Bastos, C S; Chediak, M; Guedes, R N C; Silva, R S

    2011-12-01

    The currently existing sample procedures available for decision-making regarding the control of the coffee berry borer Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) are time-consuming, expensive, and difficult to perform, compromising their adoption. In addition, the damage functions incorporated in such decision levels only consider the quantitative losses, while dismissing the qualitative losses. Traps containing ethanol, methanol, and benzaldehyde may allow cheap and easy decision-making. Our objective was to determine the economic injury level (EIL) for the adults of the coffee berry borer by using attractant-baited traps. We considered both qualitative and quantitative losses caused by the coffee borer in estimating the EILs. These EILs were determined for conventional and organic coffee under high and average plant yield. When the quantitative losses caused by H. hampei were considered alone, the EILs ranged from 7.9 to 23.7% of bored berries for high and average-yield conventional crops, respectively. For high and average-yield organic coffee the ELs varied from 24.4 to 47.6% of bored berries, respectively. When qualitative and quantitative losses caused by the pest were considered together, the EIL was 4.3% of bored berries for both conventional and organic coffee. The EILs for H. hampei associated to the coffee plants in the flowering, pinhead fruit, and ripening fruit stages were 426, 85, and 28 adults per attractive trap, respectively.

  2. Tillage, Fungicide, and Cultivar Effects on Frogeye Leaf Spot Severity and Yield in Soybean

    USDA-ARS?s Scientific Manuscript database

    Frogeye leaf spot (FLS) of soybean, caused by Cercospora sojina K. Hara, has been a problem in the southern USA for many years but has recently become an increasing problem causing significant yield losses in the northern USA. This increase in disease severity in the north USA has been attributed t...

  3. Relationship of soil properties and sugarcane yields to red stripe in Louisiana

    USDA-ARS?s Scientific Manuscript database

    Red stripe of sugarcane caused by Acidovorax avenae subsp. avenae consists of two forms: leaf stripe and top rot. Symptoms of red stripe in Louisiana observed by the authors between 1985 and 2010 were limited to the leaf stripe form which caused no apparent yield loss. During 2010, the more severe t...

  4. Transforming information from silicon testing and design characterization into numerical data sets for yield learning

    NASA Astrophysics Data System (ADS)

    Yang, Thomas; Shen, Yang; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh

    2017-03-01

    Silicon testing results are regularly collected for a particular lot of wafers to study yield loss from test result diagnostics. Product engineers will analyze the diagnostic results and perform a number of physical failure analyses to detect systematic defects which cause yield loss for these sets of wafers in order to feedback the information to process engineers for process improvements. Most of time, the systematic defects that are detected are major issues or just one of the causes for the overall yield loss. This paper will present a working flow for using design analysis techniques combined with diagnostic methods to systematically transform silicon testing information into physical layout information. A new set of the testing results are received from a new lot of wafers for the same product. We can then correlate all the diagnostic results from different periods of time to check which blocks or nets have been highlighted or stop occurring on the failure reports in order to monitor process changes which impact the yield. The design characteristic analysis flow is also implemented to find 1) the block connections on a design that have failed electrical test or 2) frequently used cells that been highlighted multiple times.

  5. Adapting the CROPGRO cotton model to simulate cotton biomass and yield under southern root-knot nematode parasitism

    USDA-ARS?s Scientific Manuscript database

    Cotton (Gossypium hirsutum L.) yield losses by southern root-knot nematode [Meloidogyne incognita (Kofoid & White) Chitwood] (RKN) are usually estimated after significant damage has been caused. However, estimation of potential yield reduction before planting is possible by using crop simulation mod...

  6. Biological control of Black Pod Disease and Seedling Blight of cacao caused by Phytophthora Species using Trichoderma from Aceh Sumatra

    USDA-ARS?s Scientific Manuscript database

    The cocoa tree, Theobroma cacao L., suffers large yield losses in Aceh Indonesia to the disease black pod rot, caused by Phytophthora spp. Despite having the largest area under cacao production in Sumatra, farmers in the Aceh region have low overall production because of losses to insect pests and b...

  7. Selection for fissure resistance now made possible in early breeding generations

    USDA-ARS?s Scientific Manuscript database

    Rice kernel fissuring is one of the leading causes of milling yield losses. Any reduction in fissuring can result in direct increases in yield and profit for both producers and millers. While most U.S. rice varieties yield around 55% head rice, the fissure-resistant varieties ‘Cypress’, ‘Saber’ an...

  8. Genotypic diversity in the responses of yield and yield components to elevated ozone of diverse inbred and hybrid maize

    USDA-ARS?s Scientific Manuscript database

    Current tropospheric ozone concentrations ([O3]), an important air pollutant, are phytotoxic and detrimental to crop yield causing significant losses of ~14-26 billion in 4 of the world’s major crops. Until recent years, it was believed that agricultural and economically important C4 plants, such as...

  9. Rain-induced spring wheat harvest losses

    NASA Technical Reports Server (NTRS)

    Bauer, A.; Black, A. L. (Principal Investigator)

    1983-01-01

    When rain or a combination of rain and high humidity delay wheat harvest, losses can occur in grain yield and/or grain quality. Yield losses can result from shattering, from reduction in test weight, and in the case of windrowed grain, from rooting of sprouting grain at the soil: windrow contact. Losses in grain quality can result from reduction in test weight and from sprouting. Sprouting causes a degradation of grain proteins and starches, hence flour quality is reduced, and the grain price deteriorates to the value of feed grain. Although losses in grain yield and quality are rain-induced, these losses do not necessarily occur because a standing or windrowed crop is wetted by rain. Spike water concentration in hard red spring wheat must be increased to about 45-49% before sprouting is initiated in grain that has overcome dormancy. The time required to overcome this dormancy after the cultivar has dried to 12 to 14% water concentration differs with hard red spring cultivars. The effect of rain on threshing-ready standing and windrowed hard red spring wheat grain yeild and quality was evaluated. A goal was to develop the capability to forecast the extent of expected loss of grain yield and quality from specific climatic events that delay threshing.

  10. Global Synthesis of Drought Effects on Maize and Wheat Production

    PubMed Central

    Daryanto, Stefani; Wang, Lixin; Jacinthe, Pierre-André

    2016-01-01

    Drought has been a major cause of agricultural disaster, yet how it affects the vulnerability of maize and wheat production in combination with several co-varying factors (i.e., phenological phases, agro-climatic regions, soil texture) remains unclear. Using a data synthesis approach, this study aims to better characterize the effects of those co-varying factors with drought and to provide critical information on minimizing yield loss. We collected data from peer-reviewed publications between 1980 and 2015 which examined maize and wheat yield responses to drought using field experiments. We performed unweighted analysis using the log response ratio to calculate the bootstrapped confidence limits of yield responses and calculated drought sensitivities with regards to those co-varying factors. Our results showed that yield reduction varied with species, with wheat having lower yield reduction (20.6%) compared to maize (39.3%) at approximately 40% water reduction. Maize was also more sensitive to drought than wheat, particularly during reproductive phase and equally sensitive in the dryland and non-dryland regions. While no yield difference was observed among regions or different soil texture, wheat cultivation in the dryland was more prone to yield loss than in the non-dryland region. Informed by these results, we discuss potential causes and possible approaches that may minimize drought impacts. PMID:27223810

  11. Genetic diversity of papaya ring spot virus in Puerto Rico

    USDA-ARS?s Scientific Manuscript database

    The Food and Agriculture Organization estimates that 20-40% of crop yield is lost due to pests and diseases. Viruses are agents that cause diseases which contribute greatly to the global yield loss. Because of this, food production is negatively affected, especially in the tropics. Carica papaya, co...

  12. Cultivar Selection for Sugar Beet Root Rot Resistance

    USDA-ARS?s Scientific Manuscript database

    Fungal and bacterial root rots in sugar beet caused by Rhizoctonia solani (Rs) and Leuconostoc mesenteroides subsp. dextranicum (Lm) can lead to root yield losses greater than 50%. To reduce the impact of these root rots on sucrose loss in the field, storage, and factories, studies were conducted t...

  13. Cultivar selection for sugarbeet root rot resistance.

    USDA-ARS?s Scientific Manuscript database

    Fungal and bacterial root rots in sugar beet caused by Rhizoctonia solani (Rs) and Leuconostoc mesenteroides subsp. dextranicum (Lm) can lead to root yield losses greater than 50%. To reduce the impact of these root rots on sucrose loss in the field, storage, and factories, studies were conducted t...

  14. Use of low-dose UV-C irradiation to control powdery mildew caused by Podosphaera aphanis on strawberry plants

    USDA-ARS?s Scientific Manuscript database

    Powdery mildew of strawberry plants, caused by Podoshaera aphanis, can cause severe losses by reducing fruit yield, quality and predisposing fruit to other diseases. Fungicides have been routinely used to control this disease. However, limitations mainly related to their effectiveness, re-entry pe...

  15. Root rot symptoms in sugar beet lines caused by Fusarium oxysporum f. sp. betae

    USDA-ARS?s Scientific Manuscript database

    The soil-borne fungus Fusarium oxysporum may cause both Fusarium yellows and Fusarium root rot diseases with severe yield losses in cultivated sugar beet worldwide. These two diseases cause similar foliar symptoms but different root response and have been proposed to be due to two distinct F. oxyspo...

  16. Evaluating an Arachis hypogaea x Arachis diogoi interspecific hybrid derived population for multiple disease resistance

    USDA-ARS?s Scientific Manuscript database

    The peanut (Arachis hypogaea L.) crop in North Carolina is subject to yield and quality loss from a number of diseases including Cylindrocladium black rot (CBR) caused by Cylindrocladium parasiticum, early leaf spot (ELS) caused by Cercospora arachidicola, late leaf spot (LLS) caused by Cercosporidi...

  17. Agrobacterium tumefaciens-mediated transformation of the soybean pathogen Phomopsis longicolla

    USDA-ARS?s Scientific Manuscript database

    Phomopsis seed decay (PSD) of soybean is caused primarily by the fungal pathogen Phomopsis longicolla. PSD impairs seed germination, reduces seedling vigor, and can substantially reduce stand establishment. In hot and humid conditions, PSD can cause significant yield losses. Few studies have explore...

  18. Association of Xylella fastidiosa with Yield Loss and Altered Fruit Quality in a Naturally Infected Rabbiteye Blueberry Orchard

    USDA-ARS?s Scientific Manuscript database

    Xylella fastidiosa causes disease in a number of plants in the southeastern United States, including southern highbush blueberry, but little was known concerning its potential impact in rabbiteye blueberry (Vaccinium virgatum). In a naturally infected orchard in Louisiana, mean yields of X. fastidi...

  19. Blackleg (Leptosphaeria maculans) Severity and Yield Loss in Canola in Alberta, Canada

    PubMed Central

    Hwang, Sheau-Fang; Strelkov, Stephen E.; Peng, Gary; Ahmed, Hafiz; Zhou, Qixing; Turnbull, George

    2016-01-01

    Blackleg, caused by Leptosphaeria maculans, is an important disease of oilseed rape (Brassica napus L.) in Canada and throughout the world. Severe epidemics of blackleg can result in significant yield losses. Understanding disease-yield relationships is a prerequisite for measuring the agronomic efficacy and economic benefits of control methods. Field experiments were conducted in 2013, 2014, and 2015 to determine the relationship between blackleg disease severity and yield in a susceptible cultivar and in moderately resistant to resistant canola hybrids. Disease severity was lower, and seed yield was 120%–128% greater, in the moderately resistant to resistant hybrids compared with the susceptible cultivar. Regression analysis showed that pod number and seed yield declined linearly as blackleg severity increased. Seed yield per plant decreased by 1.8 g for each unit increase in disease severity, corresponding to a decline in yield of 17.2% for each unit increase in disease severity. Pyraclostrobin fungicide reduced disease severity in all site-years and increased yield. These results show that the reduction of blackleg in canola crops substantially improves yields. PMID:27447676

  20. Ozone Induced Premature Mortality and Crop Yield Loss in China

    NASA Astrophysics Data System (ADS)

    Lin, Y.; Jiang, F.; Wang, H.

    2017-12-01

    Exposure to ambient ozone is a major risk factor for health impacts such as chronic obstructive pulmonary disease (COPD) and cause damage to plant and agricultural crops. But these impacts were usually evaluated separately in earlier studies. We apply Community Multi-scale Air Quality model to simulate the ambient O3 concentration at a resolution of 36 km×36 km across China. Then, we follow Global Burden of Diseases approach and AOT40 (i.e., above a threshold of 40 ppb) metric to estimate the premature mortalities and yield losses of major grain crops (i.e., winter wheat, rice and corn) across China due to surface ozone exposure, respectively. Our results show that ozone exposure leads to nearly 67,700 premature mortalities and 145 billion USD losses in 2014. The ozone induced yield losses of all crop production totaled 78 (49.9-112.6)million metric tons, worth 5.3 (3.4-7.6)billion USD, in China. The relative yield losses ranged from 8.5-14% for winter wheat, 3.9-15% for rice, and 2.2-5.5% for maize. We can see that the top four health affected provinces (Sichuan, Henan, Shandong, Jiangsu) are also ranking on the winter wheat and rice crop yield loss. Our results provide further evidence that surface ozone pollution is becoming urgent air pollution in China, and have important policy implications for China to alleviate the impacts of air pollution.

  1. Influence of Rhizoctonia-Bacterial root rot complex on storability of sugar beet

    USDA-ARS?s Scientific Manuscript database

    The root rot complex, caused by Rhizoctonia solani and Leuconostoc mesenteroides, can lead to yield loss in the field but may also lead to problems with sucrose loss in storage. Thus, studies were conducted to investigate if placing sugar beet roots suffering from root rot together with healthy roo...

  2. Illustrated manual on composting for improved soil fertility and enhanced cocoa production

    USDA-ARS?s Scientific Manuscript database

    In West and Central Africa, most cocoa farms are old and the soils are highly depleted in major nutrients. Cocoa pod harvest continues to remove nutrients, and this loss of soil fertility is one of the major causes of low cocoa yields and subsequent economic losses. Plant pathogens, including nema...

  3. Influence of sugarbeet tillage Systems on the rhizoctonia-bacterial root rot complex

    USDA-ARS?s Scientific Manuscript database

    The Rhizoctonia-bacterial root rot complex in sugarbeet caused by Rhizoctonia solani and Leuconostoc mesenteroides can cause significant yield losses. To investigate the impact of different tillage systems on this complex, field studies were conducted from 2009 to 2011. Split blocks with conventio...

  4. Influence of sugarbeet tillage systems on rhizoctonia-bacterial root rot complex

    USDA-ARS?s Scientific Manuscript database

    The Rhizoctonia-bacterial root rot complex on sugarbeet caused by Rhizoctonia solani and Leuconostoc mesenteroides can cause significant yield losses. To investigate the impact of different tillage systems on this complex, field studies were conducted from 2009 to 2011. Split blocks with conventio...

  5. GABAergic Neuron-Specific Loss of Ube3a Causes Angelman Syndrome-Like EEG Abnormalities and Enhances Seizure Susceptibility.

    PubMed

    Judson, Matthew C; Wallace, Michael L; Sidorov, Michael S; Burette, Alain C; Gu, Bin; van Woerden, Geeske M; King, Ian F; Han, Ji Eun; Zylka, Mark J; Elgersma, Ype; Weinberg, Richard J; Philpot, Benjamin D

    2016-04-06

    Loss of maternal UBE3A causes Angelman syndrome (AS), a neurodevelopmental disorder associated with severe epilepsy. We previously implicated GABAergic deficits onto layer (L) 2/3 pyramidal neurons in the pathogenesis of neocortical hyperexcitability, and perhaps epilepsy, in AS model mice. Here we investigate consequences of selective Ube3a loss from either GABAergic or glutamatergic neurons, focusing on the development of hyperexcitability within L2/3 neocortex and in broader circuit and behavioral contexts. We find that GABAergic Ube3a loss causes AS-like increases in neocortical EEG delta power, enhances seizure susceptibility, and leads to presynaptic accumulation of clathrin-coated vesicles (CCVs)-all without decreasing GABAergic inhibition onto L2/3 pyramidal neurons. Conversely, glutamatergic Ube3a loss fails to yield EEG abnormalities, seizures, or associated CCV phenotypes, despite impairing tonic inhibition onto L2/3 pyramidal neurons. These results substantiate GABAergic Ube3a loss as the principal cause of circuit hyperexcitability in AS mice, lending insight into ictogenic mechanisms in AS. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. GABAergic neuron-specific loss of Ube3a causes Angelman syndrome-like EEG abnormalities and enhances seizure susceptibility

    PubMed Central

    Judson, Matthew C.; Wallace, Michael L.; Sidorov, Michael S.; Burette, Alain C.; Gu, Bin; van Woerden, Geeske M.; King, Ian F.; Han, Ji Eun; Zylka, Mark J.; Elgersma, Ype; Weinberg, Richard J.; Philpot, Benjamin D.

    2016-01-01

    SUMMARY Loss of maternal UBE3A causes Angelman syndrome (AS), a neurodevelopmental disorder associated with severe epilepsy. We previously implicated GABAergic deficits onto layer (L) 2/3 pyramidal neurons in the pathogenesis of neocortical hyperexcitability, and perhaps epilepsy, in AS model mice. Here we investigate consequences of selective Ube3a loss from either GABAergic or glutamatergic neurons, focusing on the development of hyperexcitability within L2/3 neocortex and in broader circuit and behavioral contexts. We find that GABAergic Ube3a loss causes AS-like increases in neocortical EEG delta power, enhances seizure susceptibility, and leads to presynaptic accumulation of clathrin-coated vesicles (CCVs) – all without decreasing GABAergic inhibition onto L2/3 pyramidal neurons. Conversely, glutamatergic Ube3a loss fails to yield EEG abnormalities, seizures, or associated CCV phenotypes, despite impairing tonic inhibition onto L2/3 pyramidal neurons. These results substantiate GABAergic Ube3a loss as the principal cause of circuit hyperexcitability in AS mice, lending insight into ictogenic mechanisms in AS. PMID:27021170

  7. Transient Hearing Loss in Adults Associated With Zika Virus Infection.

    PubMed

    Vinhaes, Eriko S; Santos, Luciane A; Dias, Lislane; Andrade, Nilvano A; Bezerra, Victor H; de Carvalho, Anderson T; de Moraes, Laise; Henriques, Daniele F; Azar, Sasha R; Vasilakis, Nikos; Ko, Albert I; Andrade, Bruno B; Siqueira, Isadora C; Khouri, Ricardo; Boaventura, Viviane S

    2017-03-01

    In 2015, during the outbreak of Zika virus (ZIKV) in Brazil, we identified 3 cases of acute hearing loss after exanthematous illness. Serology yielded finding compatible with ZIKV as the cause of a confirmed (n = 1) and a probable (n = 2) flavivirus infection, indicating an association between ZIKV infection and transient hearing loss. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  8. Identification and comparative analysis of differential gene expression in soybean leaf tissue under drought and flooding stress revealed by RNA-Seq

    USDA-ARS?s Scientific Manuscript database

    Soybean is the second largest crop in the US. Its yield directly impacts US agricultural economics. Drought and flooding are two major causes for soybean yield loss. To better understand their underlying molecular regulatory mechanisms, we sequenced the transcriptomes of soybean grown in drought a...

  9. Change of arginine content and some physiological traits under midseason drought in peanut genotypes with different levels of drought resistance

    USDA-ARS?s Scientific Manuscript database

    Peanut production areas frequently suffer from drought, which can cause severe yield losses, increased aflatoxin, and compositional changes in seed. Midseason drought is generally the most detrimental to seed yields and in altering seed protein composition. The purpose of this study was to investi...

  10. Components of a rice-oilseed rape production system augmented with trichoderma sp. Tri-1 control sclerotinia sclerotiorum on oilseed rape

    USDA-ARS?s Scientific Manuscript database

    Sclerotinia sclerotiorum causes serious yield losses on many crops throughout the world. In two field trials conducted at the same location in consecutive years, a treatment containing formulated Trichoderma harzianum-1 (Tri-1) resulted in oilseed rape seed yield that was significantly greater than...

  11. Consequences of waterlogging in cotton and opportunities for mitigation of yield losses

    PubMed Central

    Najeeb, Ullah; Bange, Michael P.; Tan, Daniel K. Y.; Atwell, Brian J.

    2015-01-01

    Climatic variability, typified by erratic heavy-rainfall events, causes waterlogging in intensively irrigated crops and is exacerbated under warm temperature regimes on soils with poor internal drainage. Irrigated cotton is often grown in precisely these conditions, exposing it to waterlogging-induced yield losses after substantial summer rainfall. This calls for a deeper understanding of mechanisms of waterlogging tolerance and its relevance to cotton. Hence this review suggests possible causes of waterlogging-induced yield loss in cotton and approaches to improvement of waterlogging tolerance, drawing upon the slight body of published data in cotton and principles from other species. The yield penalty depends on soil type, phenological stage and cumulative period of root exposure to air-filled porosities below 10 %. Events in the soil include O2 deficiency in the root zone that changes the redox state of nutrients, making them unavailable (e.g. nitrogen) or potentially toxic for plants. Furthermore, root-derived hormones that are transported in the xylem have long been associated with oxygen deficits. These belowground effects (impaired root growth, nutrient uptake and transport, hormonal signalling) affect the shoots, interfering with canopy development, photosynthesis and radiation-use efficiency. Compared with the more waterlogging-tolerant cereals, cotton does not have identified adaptations to waterlogging in the root zone, forming no conspicuous root aerenchyma and having low fermentative activity. We speculate that these factors contribute substantially to the sensitivity of cotton to sustained periods of waterlogging. We discuss the impact of these belowground factors on shoot performance, photosynthesis and yield components. Management practices, i.e. soil aeration, scheduling irrigation and fertilizer application, can reduce waterlogging-induced damage. Limiting ethylene biosynthesis using anti-ethylene agents and down-regulating expression of genes controlling ethylene biosynthesis are strong candidates to minimize yield losses in waterlogged cotton crops. Other key pathways of anoxia tolerance are also cited as potential tools towards waterlogging-tolerant cotton genotypes. PMID:26194168

  12. A method for determining the severity of Sudden Death Syndrome in soybeans

    USDA-ARS?s Scientific Manuscript database

    Sudden death syndrome (SDS), caused by the fungus Fusarium virguliforme, is a widespread mid- to late- season soybean disease with distinctive foliar symptoms that in some extreme cases may cause nearly 100% yield loss. This article reports on the development of an image analysis method to quantify ...

  13. Influence of tillage systems on Rhizoctonia-bacterial root rot complex in sugar beet

    USDA-ARS?s Scientific Manuscript database

    The Rhizoctonia-bacterial root rot complex on sugarbeet caused by Rhizoctonia solani and Leuconostoc mesenteroides can cause significant yield losses. To investigate the impact of different tillage systems on this complex, field studies were conducted from 2009 to 2011. Split blocks with conventio...

  14. Distribution of canker lesions on the surface of diseased grapefruit

    USDA-ARS?s Scientific Manuscript database

    Citrus canker (caused by Xanthomonas citri subsp. citri) can cause direct yield loss of citrus, and infection of fruit can result in trade restriction being imposed on canker endemic areas. Developing fruit become infected through splash dispersed inoculum. The objective of this study was to describ...

  15. Image processing methods for quantitatively detecting soybean rust from multispectral images

    USDA-ARS?s Scientific Manuscript database

    Soybean rust, caused by Phakopsora pachyrhizi, is one of the most destructive diseases for soybean production. It often causes significant yield loss and may rapidly spread from field to field through airborne urediniospores. In order to implement timely fungicide treatments for the most effective c...

  16. Temporal dynamics and population genetic structure of Fusarium graminearum in the upper Midwestern United States

    USDA-ARS?s Scientific Manuscript database

    Fusarium graminearum sensu stricto causes Fusarium head blight (FHB) in wheat and barley, and contaminates grains with several trichothecene mycotoxins, causing destructive yield losses and economic impact in the United States. Recently, a F. graminearum strain collected from Minnesota (MN) was dete...

  17. Genome-wide informative microsatellite database and global population structure of Fusarium virguliforme

    USDA-ARS?s Scientific Manuscript database

    Sudden death syndrome is one of the leading biotic stresses responsible for soybean yield loss in major soybean production areas. In North America, the disease is caused by the fungus Fusarium virguliforme, while in South America additional Fusarium species cause similar symptoms. Breeding for SDS r...

  18. Reaction of Diaporthe longicolla to a strain of Sarocladium kiliense

    USDA-ARS?s Scientific Manuscript database

    Phomopsis seed decay (PSD) of soybean [Glycine max (L.) Merr.] is a seedborne fungal disease caused by Diaporthe (syn. Phomopsis) longicolla that causes yield losses and reduced seed quality. Biocontrol of this pathogen by a strain of Acremonium strictum isolated from a culture of D. longicolla was ...

  19. Virulence diversity of Phakopsora pachyrhizi isolates from East Africa compared to a geographically diverse collection

    USDA-ARS?s Scientific Manuscript database

    Soybean rust, caused by the biotrophic pathogen Phakopsora pachyrhizi, is a highly destructive disease causing substantial yield losses in many soybean producing regions throughout the world. Knowledge about P. pachyrhizi virulence is needed to guide development and deployment of soybean germplasm w...

  20. Vertical distribution of scab in large pecan trees

    USDA-ARS?s Scientific Manuscript database

    Pecan scab (caused by Fusicladium effusum) is a destructive disease of pecan (Carya illinoensis) grown in humid environments, such as the southeastern US. The disease can cause severe yield loss, and although much is known about the processes of dispersal and infection, there is no information on di...

  1. Genome-wide association mapping reveals novel QTL for seedling leaf rust resistance in a worldwide collection of winter wheat

    USDA-ARS?s Scientific Manuscript database

    Leaf rust is a major disease that causes significant wheat yield losses worldwide. Growing resistant cultivars is an effective approach to reduce disease losses. The short-lived nature of leaf rust resistance (Lr) genes necessitates a continuous search for novel sources of resistance. We performe...

  2. Early generation selection for rice fissure resistance proves effective and indicates a fissure resistance gene on chromsome 1

    USDA-ARS?s Scientific Manuscript database

    Whole rice kernels have two to three times more market value than brokens, which means that any reduction in milling yield results in financial losses for both rice producers and millers. One of the leading causes of reduced milling yield is exposure of the rice kernels to severe moisture changes b...

  3. A comparative study of three detection techniques for Leifsonia xyli subsp. xyli, the causal pathogen of sugarcane ratoon stunting disease

    USDA-ARS?s Scientific Manuscript database

    Ratoon stunting disease (RSD), which is caused by the bacterium Leifsonia xyli subsp. xyli (Lxx), is now recognized worldwide as the most economically devastating disease impacting sugarcane. RSD causes significant yield losses and variety degradation. Diagnosis of RSD is challenging because it does...

  4. First report of mango malformation disease caused by Fusarium pseudocircinatum in Mexico

    USDA-ARS?s Scientific Manuscript database

    Mango (Mangifera indica L.) malformation disease (MMD) is one of the most important diseases affecting this crop worldwide, causing severe economic loss due to reduction of yield. Subsequent to the first report in India in 1891 (3), MMD has spread worldwide to most mango-growing regions. Several spe...

  5. Inter-chromosomal transfer of immune regulation during infection of barley with the powdery mildew pathogen

    USDA-ARS?s Scientific Manuscript database

    Powdery mildews infect over 9,500 plant species, causing critical yield loss. Powdery mildew disease of barley is caused by the Ascomycete fungus, Blumeria graminis f. sp. hordei (Bgh) and has become a model for the interactions among obligate biotrophs and their cereal hosts. Successful infection r...

  6. Using transcription of six Puccinia triticina races to identify the secretome during infection of wheat

    USDA-ARS?s Scientific Manuscript database

    Wheat leaf rust, caused by the basidiomycete Puccinia triticina, can cause yield losses of up to 20% in wheat-producing regions. During infection, the fungus forms haustoria that secrete proteins into the plant cell and effect changes in plant transcription, metabolism and defense. It is hypothesize...

  7. Genome-wide association analysis of powdery mildew resistance in U.S. winter wheat

    USDA-ARS?s Scientific Manuscript database

    Wheat powdery mildew (PM), caused by Blumeria graminis f. sp. tritici, is a major fungal disease of wheat worldwide. It can cause considerable yield losses when epidemics occur. Use of genetic resistance is the most effective approach to control the disease. To determine the genomic regions responsi...

  8. Postharvest respiration rate and sucrose concentration of Rhizoctonia-infected sugar beet roots

    USDA-ARS?s Scientific Manuscript database

    Rhizoctonia crown and root rot (RCRR), caused by Rhizoctonia solani AG 2-2, is a common root disease on sugar beet that reduces yield and sucrose during the growing season and causes further losses by increasing respiration and reducing sucrose content during storage. The industry needs to identify...

  9. Spray Coverage, Hedging and Pecan Scab - an Update on Research

    USDA-ARS?s Scientific Manuscript database

    Pecan scab is caused by the fungus Fusicladium effusum, and is the major disease of pecan in Georgia and elsewhere in the region, causing severe yield loss in some seasons and areas. There are several reasons for hedging, and some issues may arise as a result of the hedging management practice. Thre...

  10. Using pattern analysis methods to do fast detection of manufacturing pattern failures

    NASA Astrophysics Data System (ADS)

    Zhao, Evan; Wang, Jessie; Sun, Mason; Wang, Jeff; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh; Ding, Hua

    2016-03-01

    At the advanced technology node, logic design has become extremely complex and is getting more challenging as the pattern geometry size decreases. The small sizes of layout patterns are becoming very sensitive to process variations. Meanwhile, the high pressure of yield ramp is always there due to time-to-market competition. The company that achieves patterning maturity earlier than others will have a great advantage and a better chance to realize maximum profit margins. For debugging silicon failures, DFT diagnostics can identify which nets or cells caused the yield loss. But normally, a long time period is needed with many resources to identify which failures are due to one common layout pattern or structure. This paper will present a new yield diagnostic flow, based on preliminary EFA results, to show how pattern analysis can more efficiently detect pattern related systematic defects. Increased visibility on design pattern related failures also allows more precise yield loss estimation.

  11. Vegetable Grafting as a Tool to Improve Drought Resistance and Water Use Efficiency

    PubMed Central

    Kumar, Pradeep; Rouphael, Youssef; Cardarelli, Mariateresa; Colla, Giuseppe

    2017-01-01

    Drought is one of the most prevalent limiting factors causing considerable losses in crop productivity, inflicting economic as well as nutritional insecurity. One of the greatest challenges faced by the scientific community in the next few years is to minimize the yield losses caused by drought. Drought resistance is a complex quantitative trait controlled by many genes. Thus, introgression of drought resistance traits into high yielding genotypes has been a challenge to plant breeders. Vegetable grafting using rootstocks has emerged as a rapid tool in tailoring plants to better adapt to suboptimal growing conditions. This has induced changes in shoot physiology. Grafting applications have expanded mainly in Solanaceous crops and cucurbits, which are commonly grown in arid and semi-arid areas characterized by long drought periods. The current review gives an overview of the recent scientific literature on root-shoot interaction and rootstock-driven alteration of growth, yield, and fruit quality in grafted vegetable plants under drought stress. Further, we elucidate the drought resistance mechanisms of grafted vegetables at the morpho-physiological, biochemical, and molecular levels. PMID:28713405

  12. Dynamic model-based N management reduces surplus nitrogen and improves the environmental performance of corn production

    NASA Astrophysics Data System (ADS)

    Sela, S.; Woodbury, P. B.; van Es, H. M.

    2018-05-01

    The US Midwest is the largest and most intensive corn (Zea mays, L.) production region in the world. However, N losses from corn systems cause serious environmental impacts including dead zones in coastal waters, groundwater pollution, particulate air pollution, and global warming. New approaches to reducing N losses are urgently needed. N surplus is gaining attention as such an approach for multiple cropping systems. We combined experimental data from 127 on-farm field trials conducted in seven US states during the 2011–2016 growing seasons with biochemical simulations using the PNM model to quantify the benefits of a dynamic location-adapted management approach to reduce N surplus. We found that this approach allowed large reductions in N rate (32%) and N surplus (36%) compared to existing static approaches, without reducing yield and substantially reducing yield-scaled N losses (11%). Across all sites, yield-scaled N losses increased linearly with N surplus values above ~48 kg ha‑1. Using the dynamic model-based N management approach enabled growers to get much closer to this target than using existing static methods, while maintaining yield. Therefore, this approach can substantially reduce N surplus and N pollution potential compared to static N management.

  13. First Report of Orange Rust of Sugarcane caused by Puccinia kuehnii in Ecuador

    USDA-ARS?s Scientific Manuscript database

    Orange rust, Puccinia kuehnii (W. Krüger) E.J. Butler, is an important disease of sugarcane (complex hybrid of Saccharum L. species) that causes yield losses, and impacts breeding programs. Initially confined to the Asia-Oceania region (5), P. kuehnii was reported in Florida in June 2007 (2) and lat...

  14. Evaluation of maturity group III soybean lines for resistance to purple seed stain in Mississippi, 2010

    USDA-ARS?s Scientific Manuscript database

    Purple seed stain (PSS) of soybean is an important disease caused by Cercospora kikuchii. PSS reduces seed quality and market grade, affects seed germination and vigor, and has been reported wherever soybeans are grown worldwide. In 2009, PSS caused 6.4 million bushels of yield losses in 16 southern...

  15. Reaction of maturity group V soybean lines to purple seed stains in Mississippi 2010

    USDA-ARS?s Scientific Manuscript database

    In 2009, soybean purple seed stain (PSS) caused 6.4 million bushels of yield losses in 16 southern states. This disease severely reduces seed market grade and affects seed germination and vigor. PSS is caused by Cercospora kikuchii and is an economy important disease. To identify new sources of resi...

  16. Evaluation of maturity group IV soybean lines for resistance to purple seed stains in Mississippi 2010

    USDA-ARS?s Scientific Manuscript database

    Purple seed stain (PSS) of soybean is an important disease caused by Cercospora kikuchii. PSS reduces seed quality and market grade, affects seed germination and vigor, and has been reported wherever soybeans are grown worldwide. In 2009, PSS caused 6.4 million bushels of yield losses in 16 southern...

  17. The inheritance of resistance to bacterial leaf spot of lettuce caused by Xanthomonas campestris pv. vitians in three lettuce cultivars

    USDA-ARS?s Scientific Manuscript database

    Lettuce yields can be reduced by the disease bacterial leaf spot (BLS) caused by the pathogen Xanthomonas campestris pv. vitians (Xcv) and host resistance is the most feasible method to reduce disease losses. The cultivars La Brillante, Pavane, and Little Gem express an incompatible host-pathogen in...

  18. Evaluation of soybean genotypes for resistance to charcoal rot

    USDA-ARS?s Scientific Manuscript database

    Charcoal rot caused by Macrophomina phaseolina causes more yield loss in soybean than most other diseases in the southern U.S.A. There are no commercial genotypes marketed as resistant to charcoal rot of soybean. Reactions of 27 maturity group (MG) III, 29 Early MG IV, 34 Late MG IV, and 59 MG V gen...

  19. Genetic mapping of race-specific stem rust resistance in the synthetic hexaploid W7984 x Opata M85 mapping population

    USDA-ARS?s Scientific Manuscript database

    Stem rust (caused by Puccinia graminis f. sp. tritici) has historically caused severe yield losses of wheat (Triticum aestivum) worldwide and has been one of the most feared diseases of wheat and barley (Hordeum vulgare). Stem rust has been controlled successfully through the use of resistant varie...

  20. Identification of wheat gene Sr35 that confers resistance to Ug99 stem rust race group

    USDA-ARS?s Scientific Manuscript database

    Wheat stem rust, caused by Puccinia graminis f. sp. tritici (Pgt) is a devastating disease that can cause severe yield losses. A new Pgt race designated Ug99 has overcome most of the widely used resistance genes and is spreading through Africa and Asia threatening major wheat production areas. We re...

  1. An opportunistic Pantoea sp. isolated from a cotton fleahopper that is capable of causing cotton (Gossypium hirsutum L.) bud rot

    USDA-ARS?s Scientific Manuscript database

    Pantoea ananatis (Serano) representatives are known to have a broad host range including both humans and plants. The cotton fleahopper (Pseudatomoscelis seriatus, Reuter) is a significant pest that causes cotton bud damage that may result in significant yield losses. In this study, cotton fleahopp...

  2. Relationships of Initial Population Densities of Meloidogyne incognita and M. hapla to Yield of Tomato

    PubMed Central

    Barker, K. R.; Shoemaker, P. B.; Nelson, L. A.

    1976-01-01

    Microplots 80 × 100 cm, infested with varying initial population densities (Pi) of Meloidogyne incognita or M. hapla, were planted to tomato at two locations. Experiments were conducted in a sandy loam soil at Fletcher, N. C. (mountains) where the mean temperature for May to September is ca 20.7 C, and in a loamy saml at Clayton, N. C. (coastal plain) where the mean temperature for May to Septemher is ca 24.8 C. In these experimentally infested plots, M. incognita and M. hapla caused maximunt yield losses of 20-30%, at lhe mountain site with Pi of 0-12,500 eggs and larvae/500 cm³ of soil. In the coaslal plain, M. incognita suppressed yields up to 85%, and M. hapla suppressed yields up to 50% in comparison with the noninfested control. A part of the high losses at this site apparently was due to M. incognita predisposing tomato to the early blight fungus. In a second experintent, in which a nematicide was used to obtain a range of Pis (with Pi as high as 25,000/50 cm³ of soil) at Fletcher, losses due to M. incognita were as great as 50%, but similar densities of M. hapla suppressed yields by only 10-25%. Approximate threshold densities for both species ranged from 500 to 1,000 larvae and eggs (higher for surviving larvae) for the mountain site, whereas nutnbers as low as 20 larvae/500 cm³ of soil of either species caused signiticant damage in the coastal plain. Chemical soil treatments proved useful in obtaining various initial population densities; however, problems were encountered in measuring effective inoculum after such treatments, especially in the heavier soil. PMID:19308228

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

    Saunders, Will; Smedley, Scott; Gillingham, Peter

    We present Simulated Annealing fiber-to-target allocation simulations for the proposed DESI and 4MOST massively multiplexed spectroscopic surveys, and for both Poisson and realistically clustered mock target samples. We simulate both Echidna and theta-phi actuator designs, including the restrictions caused by the physical actuator characteristics during repositioning. For DESI, with theta-phi actuators, used in 5 passes over the sky for a mock ELG/LRG/QSO sample, with matched fiber and target densities, a total target allocation yield of 89.3% was achieved, but only 83.7% for the high-priority Ly-alpha QSOs. If Echidna actuators are used with the same pitch and number of passes, themore » yield increases by 5.7% and 16% respectively. Echidna also allows a factor-of-two increase in the number of close Ly-alpha QSO pairs that can be observed. Echidna spine tilt causes a variable loss of throughput, with average loss being the same as the loss at the rms tilt. With a natural tilt minimization scheme, we find an rms tilt always close to 0.58 x maximum. There is an additional but much smaller defocus loss, equivalent to an average defocus of 30microns. These tilt losses offset the gains in yield for Echidna, but because the survey strategy is driven by the higher priority targets, a clear survey speed advantage remains. For 4MOST, high and low latitude sample mock catalogs were supplied by the 4MOST team, and allocations were carried out with the proposed Echidna-based positioner geometry. At high latitudes, the resulting target completeness was 85.3% for LR targets and 78.9% for HR targets. At low latitude, the target completeness was 93.9% for LR targets and 71.2% for HR targets.« less

  4. First report of pecan bacterial leaf scorch caused by Xylella fastidiosa in pecan (Carya illinoinensis) in Arizona, New Mexico, California, and Texas

    USDA-ARS?s Scientific Manuscript database

    Pecan bacterial leaf scorch (PBLS) is a chronic disease that can cause major yield losses in pecan orchards. In the 2015-16 growing seasons, symptoms consistent with PBLS were observed in commercial pecan cultivars in AZ, NM, CA and TX. Symptoms included tan to light brown necrotic lesions, which ...

  5. Markers linked to wheat stem rust resistance gene Sr11 effective to Puccinia graminis f. sp. tritici race TKTTF

    USDA-ARS?s Scientific Manuscript database

    Wheat stem rust caused by Puccinia graminis f. sp. tritici can cause severe yield losses on susceptible wheat varieties and cultivars. Although stem rust can be controlled by the use of genetic resistance, population dynamics of P. graminis f. sp. tritici can frequently lead to defeat of wheat stem ...

  6. QTL mapping of multiple independent loci for resistance to fusarium wilt races 1 and 4 in an interspecific cotton population

    USDA-ARS?s Scientific Manuscript database

    Fusarium wilt, caused by the soil-borne fungal pathogen Fusarium oxysporum f. sp. vasinfectum (FOV), is a vascular disease of cotton (Gossypium spp.). FOV race 1 (FOV1) causes major plant injury and yield loss in G. hirsutum cultivars with co-infection with root-knot nematode (Meloidogyne incognita)...

  7. Comment of "Event-based soil loss models for construction sites" by Trenouth and Gharabaghi, J. Hydrol. doi: 10.1016/jhydrol.2015.03.010

    NASA Astrophysics Data System (ADS)

    Kinnell, P. I. A.

    2015-09-01

    Trenouth and Gharabaghi (2015) present two models which replace the EI30 index used as the event erosivity index in the USLE/RUSLE with ones that include runoff and values of EI30 to powers that differ for 1.0 as the event erosivity factor in modelling soil loss for construction sites. Their analysis on the application of these models focused on data from 5 locations as a whole but did not show how the models worked at each location. Practically, the ability to predict sediment yields at a specific location is more relevant than the capacity of a model to predict sediment yields globally. Also, the mathematical structure of their proposed models shows little regard to the physical processes involved in causing erosion and sediment yield. There is still the need to develop event-based empirical models for construction sites that are robust because they give proper consideration to the erosion process involved, and take account of the fact that sediment yield is usually determined from measurements of suspended load whereas soil loss at the scale for which the USLE/RUSLE model was developed includes both suspended load and bed load.

  8. The effect of subclinical mastitis on milk yield in dairy goats.

    PubMed

    Koop, G; van Werven, T; Schuiling, H J; Nielen, M

    2010-12-01

    The aims of this study were to estimate milk yield (MY) losses associated with subclinical intramammary infection (IMI) in dairy goats and to assess if somatic cell count (SCC) can be used to estimate such MY losses. We used 2 data sets to study these questions. The first data set consisted of 5 herds. Milk production and SCC were recorded during 1 lactation. From approximately 100 does in each herd, milk samples were collected on 3 occasions during lactation for bacteriological culture. Linear mixed regression was used to estimate the effect of IMI on MY. The second data set consisted of 6 large herds, in which some of the goats had an extended lactation (≥2 yr). Milk yield and SCC data were recorded without bacteriological culture. The data showed that bacterial infection was related to an increase in SCC. Infections with major pathogens were rare and associated with a decreased MY; infection with coagulase-negative staphylococci did not affect MY, whereas infection with Corynebacterium bovis was associated with increased MY. A negative correlation was observed between SCC and MY, but the data suggested that this negative correlation was attenuated rather than caused by IMI. Furthermore, SCC seemed to be affected by MY via a dilution effect. Hypotheses about biological mechanisms behind these observations are discussed. This paper shows that MY losses caused by subclinical udder infections are limited in goats, and that SCC cannot be used to estimate the magnitude of these losses. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. QTL mapping of sulfur tolerance in melon

    USDA-ARS?s Scientific Manuscript database

    Elemental sulfur is a cheap, effective fungicide with multi-site action, which inhibits the evolution of pathogen resistance. Fungal pathogens cause significant yield losses in melon production. Many melon genotypes, however, suffer leaf necrosis in response to elemental sulfur application preventin...

  10. Identification and characterization of a CLE domain-containing protein from Rotylenchulus reniformis

    USDA-ARS?s Scientific Manuscript database

    The reniform nematode, Rotylenchulus reniformis, is a sedentary semi-endoparasite that causes significant yield loss on many economically important crops including cotton, soybean, and pineapple. Vermiform infective female nematodes secrete esophageal gland effector proteins, encoded by parasitism ...

  11. Identification of pecan scab resistance gene candidates in a pecan provenance collection using a combined bulked segregant analysis and genotyping by sequencing approach

    USDA-ARS?s Scientific Manuscript database

    Pecan [Carya illinoinensis (Wangenh.) K. Koch] is an important horticultural crop in the USA worth over $560 million in 2015. Pecan is a diploid species endemic to the Mississippi River Valley. Pecan scab is caused by the fungus Fusicladium effusum and infection causes losses in nut yield and qualit...

  12. Identification of quantitative trait loci (QTLs) responsible for sheath blight resistance in rice using recombinant inbred line population of Lemont X Jasmine 85

    USDA-ARS?s Scientific Manuscript database

    Rice sheath blight (RSB) caused by the soil borne pathogen Rhizoctonia solani, is one of the most destructive diseases of rice, causing severe losses in rice yield and quality annually. The major gene (s) governing the resistance to RSB have not been found in cultivated rice worldwide. However, ri...

  13. Expression of apoplast-targeted plant defensin MtDef4.2 confers resistance to leaf rust pathogen Puccinia triticina but does not affect mycorrhizal symbiosis in transgenic wheat

    USDA-ARS?s Scientific Manuscript database

    Rust diseases caused by Puccinia spp. pose a major threat to global wheat production. Puccinia triticina (Pt), an obligate basidiomycete biotroph, causes leaf rust disease which incurs yield losses of up to 50% in wheat. Historically, resistant wheat cultivars have been used to control leaf rust, bu...

  14. A genome-wide association study of field and seedling response to stem rust pathogen races reveals combinations of race-specific resistance genes in North American spring wheat

    USDA-ARS?s Scientific Manuscript database

    Stem rust of wheat caused by the fungal pathogen Puccinia graminis f. sp. tritici historically caused major yield losses of wheat worldwide. To understand the genetic basis of stem rust resistance in conventional North American spring wheat, genome-wide association analysis (GWAS) was conducted on a...

  15. Maintaining yields and reducing nitrogen loss in rice-wheat rotation system in Taihu Lake region with proper fertilizer management

    NASA Astrophysics Data System (ADS)

    Xue, Lihong; Yu, Yingliang; Yang, Linzhang

    2014-11-01

    In the Tailake region of China, heavy nitrogen (N) loss of rice-wheat rotation systems, due to high fertilizer-N input with low N use efficiency (NUE), was widely reported. To alleviate the detrimental impacts caused by N loss, it is necessary to improve the fertilizer management practices. Therefore, a 3 yr field experiments with different N managements including organic combined chemical N treatment (OCN, 390 kg N ha-1 yr-1, 20% organic fertilizer), control-released urea treatment (CRU, 390 kg N ha-1 yr-1, 70% resin-coated urea), reduced chemical N treatment (RCN, 390 kg N ha-1 yr-1, all common chemical fertilizer), and site-specific N management (SSNM, 333 kg N ha-1 yr-1, all common chemical fertilizer) were conducted in the Taihu Lake region with the ‘farmer’s N’ treatment (FN, 510 kg N ha-1 yr-1, all common chemical fertilizer) as a control. Grain yield, plant N uptake (PNU), NUE, and N losses via runoff, leaching, and ammonia volatilization were assessed. In the rice season, the FN treatment had the highest N loss and lowest NUE, which can be attributed to an excessive rate of N application. Treatments of OCN and RCN with a 22% reduced N rate from FN had no significant effect on PNU nor the yield of rice in the 3 yr; however, the NUE was improved and N loss was reduced 20-32%. OCN treatment achieved the highest yield, while SSNM has the lowest N loss and highest NUE due to the lowest N rate. In wheat season, N loss decreased about 28-48% with the continuous reduction of N input, but the yield also declined, with the exception of OCN treatment. N loss through runoff, leaching and ammonia volatilization was positively correlated with the N input rate. When compared with the pure chemical fertilizer treatment of RCN under the same N input, OCN treatment has better NUE, better yield, and lower N loss. 70% of the urea replaced with resin-coated urea had no significant effect on yield and NUE improvement, but decreased the ammonia volatilization loss. Soil total N and organic matter content showed a decrease after three continuous cropping years with inorganic fertilizer application alone, but there was an increase with the OCN treatment. N balance analysis showed a N surplus for FN treatment and a balanced N budget for OCN treatment. To reduce the environmental impact and maintain a high crop production, proper N reduction together with organic amendments could be sustainable in the rice-wheat rotation system in the Taihu Lake region for a long run.

  16. Automated reticle inspection data analysis for wafer fabs

    NASA Astrophysics Data System (ADS)

    Summers, Derek; Chen, Gong; Reese, Bryan; Hutchinson, Trent; Liesching, Marcus; Ying, Hai; Dover, Russell

    2008-10-01

    To minimize potential wafer yield loss due to mask defects, most wafer fabs implement some form of reticle inspection system to monitor photomask quality in high-volume wafer manufacturing environments. Traditionally, experienced operators review reticle defects found by an inspection tool and then manually classify each defect as 'pass, warn, or fail' based on its size and location. However, in the event reticle defects are suspected of causing repeating wafer defects on a completed wafer, potential defects on all associated reticles must be manually searched on a layer-by-layer basis in an effort to identify the reticle responsible for the wafer yield loss. This 'problem reticle' search process is a very tedious and time-consuming task and may cause extended manufacturing line-down situations. Often times, Process Engineers and other team members need to manually investigate several reticle inspection reports to determine if yield loss can be tied to a specific layer. Because of the very nature of this detailed work, calculation errors may occur resulting in an incorrect root cause analysis effort. These delays waste valuable resources that could be spent working on other more productive activities. This paper examines an automated software solution for converting KLA-Tencor reticle inspection defect maps into a format compatible with KLA-Tencor's Klarity DefecTM data analysis database. The objective is to use the graphical charting capabilities of Klarity Defect to reveal a clearer understanding of defect trends for individual reticle layers or entire mask sets. Automated analysis features include reticle defect count trend analysis and potentially stacking reticle defect maps for signature analysis against wafer inspection defect data. Other possible benefits include optimizing reticle inspection sample plans in an effort to support "lean manufacturing" initiatives for wafer fabs.

  17. Automated reticle inspection data analysis for wafer fabs

    NASA Astrophysics Data System (ADS)

    Summers, Derek; Chen, Gong; Reese, Bryan; Hutchinson, Trent; Liesching, Marcus; Ying, Hai; Dover, Russell

    2009-04-01

    To minimize potential wafer yield loss due to mask defects, most wafer fabs implement some form of reticle inspection system to monitor photomask quality in high-volume wafer manufacturing environments. Traditionally, experienced operators review reticle defects found by an inspection tool and then manually classify each defect as 'pass, warn, or fail' based on its size and location. However, in the event reticle defects are suspected of causing repeating wafer defects on a completed wafer, potential defects on all associated reticles must be manually searched on a layer-by-layer basis in an effort to identify the reticle responsible for the wafer yield loss. This 'problem reticle' search process is a very tedious and time-consuming task and may cause extended manufacturing line-down situations. Often times, Process Engineers and other team members need to manually investigate several reticle inspection reports to determine if yield loss can be tied to a specific layer. Because of the very nature of this detailed work, calculation errors may occur resulting in an incorrect root cause analysis effort. These delays waste valuable resources that could be spent working on other more productive activities. This paper examines an automated software solution for converting KLA-Tencor reticle inspection defect maps into a format compatible with KLA-Tencor's Klarity Defect(R) data analysis database. The objective is to use the graphical charting capabilities of Klarity Defect to reveal a clearer understanding of defect trends for individual reticle layers or entire mask sets. Automated analysis features include reticle defect count trend analysis and potentially stacking reticle defect maps for signature analysis against wafer inspection defect data. Other possible benefits include optimizing reticle inspection sample plans in an effort to support "lean manufacturing" initiatives for wafer fabs.

  18. Automated reticle inspection data analysis for wafer fabs

    NASA Astrophysics Data System (ADS)

    Summers, Derek; Chen, Gong; Reese, Bryan; Hutchinson, Trent; Liesching, Marcus; Ying, Hai; Dover, Russell

    2009-03-01

    To minimize potential wafer yield loss due to mask defects, most wafer fabs implement some form of reticle inspection system to monitor photomask quality in high-volume wafer manufacturing environments. Traditionally, experienced operators review reticle defects found by an inspection tool and then manually classify each defect as 'pass, warn, or fail' based on its size and location. However, in the event reticle defects are suspected of causing repeating wafer defects on a completed wafer, potential defects on all associated reticles must be manually searched on a layer-by-layer basis in an effort to identify the reticle responsible for the wafer yield loss. This 'problem reticle' search process is a very tedious and time-consuming task and may cause extended manufacturing line-down situations. Often times, Process Engineers and other team members need to manually investigate several reticle inspection reports to determine if yield loss can be tied to a specific layer. Because of the very nature of this detailed work, calculation errors may occur resulting in an incorrect root cause analysis effort. These delays waste valuable resources that could be spent working on other more productive activities. This paper examines an automated software solution for converting KLA-Tencor reticle inspection defect maps into a format compatible with KLA-Tencor's Klarity DefectTM data analysis database. The objective is to use the graphical charting capabilities of Klarity Defect to reveal a clearer understanding of defect trends for individual reticle layers or entire mask sets. Automated analysis features include reticle defect count trend analysis and potentially stacking reticle defect maps for signature analysis against wafer inspection defect data. Other possible benefits include optimizing reticle inspection sample plans in an effort to support "lean manufacturing" initiatives for wafer fabs.

  19. SSR Markers Assessed for Peanut Smut Disease Resistance

    USDA-ARS?s Scientific Manuscript database

    Peanut smut disease, caused by Thecaphora frezii (Carranza & Lindquist), can result in yield losses higher than 50%. Several strategies have been developed for disease management but they are still insufficient. The smut genetic resistance found in wild species and Bolivian landraces is currently th...

  20. Utilization of Molecular Detection Techniques to Find Soybean Pathogens

    USDA-ARS?s Scientific Manuscript database

    Soybeans continue to rise in prominence as a source of feed, food, oil, and renewable energy. Of many factors impacting yield, microbial pathogens alone can cause significant losses in production. Management of soybean diseases and pests involves many approaches including cultural aspects like crop ...

  1. Black pod: diverse pathogens with a global impact on cocoa yield.

    PubMed

    Guest, David

    2007-12-01

    ABSTRACT Pathogens of the Straminipile genus Phytophthora cause significant disease losses to global cocoa production. P. megakarya causes significant pod rot and losses due to canker in West Africa, whereas P. capsici and P. citrophthora cause pod rots in Central and South America. The global and highly damaging P. palmivora attacks all parts of the cocoa tree at all stages of the growing cycle. This pathogen causes 20 to 30% pod losses through black pod rot, and kills up to 10% of trees annually through stem cankers. P. palmivora has a complex disease cycle involving several sources of primary inoculum and several modes of dissemination of secondary inoculum. This results in explosive epidemics during favorable environmental conditions. The spread of regional pathogens must be prevented by effective quarantine barriers. Resistance to all these Phytophthora species is typically low in commercial cocoa genotypes. Disease losses can be reduced through integrated management practices that include pruning and shade management, leaf mulching, regular and complete harvesting, sanitation and pod case disposal, appropriate fertilizer application and targeted fungicide use. Packaging these options to improve uptake by smallholders presents a major challenge for the industry.

  2. Combination of RNAseq and SNP nanofluidic array reveals the center of genetic diversity of cacao pathogen Moniliophthora roreri in the upper Magdalena Valley of Colombia and its clonality

    USDA-ARS?s Scientific Manuscript database

    Moniliophthora roreri is the fungal pathogen that causes frosty pod rot (FPR) disease of Theobroma cacao L., the source of chocolate. FPR occurs in most of the cacao producing countries in the Western Hemisphere, causing yield losses up to 80%. Genetic diversity within the FPR pathogen population ma...

  3. Genetics and breeding of bacterial leaf spot resistance

    USDA-ARS?s Scientific Manuscript database

    Bacterial leaf spot (BLS) caused by the pathogen Xanthomonas campestris pv. vitians (Xcv) is a globally important disease of whole head and baby leaf lettuce that reduces crop yield and quality. Host resistance is the most feasible method to reduce disease losses. Screening Lactuca accessions has id...

  4. Genetic characterization of resistance to Sclerotinia in lettuce cultivar Eruption

    USDA-ARS?s Scientific Manuscript database

    Lettuce drop caused by the fungal pathogens Sclerotinia minor and S. sclerotiorum is a serious disease of lettuce. The use of genetic resistance as part of an integrated lettuce drop management strategy should have a significant economic advantage in mitigating yield loss. Sclerotinia resistance is ...

  5. The conundrum of chemical boll weevil control in subtropical regions

    USDA-ARS?s Scientific Manuscript database

    The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a tropical Mesoamerican insect that invaded the United States in 1893, spreading across the Cotton Belt as the key pest of cotton and causing billions of dollars in yield losses and insecticide-based control efforts;...

  6. Altered heme catabolism by heme oxygenase-1 caused by mutations in human NADPH cytochrome P450 reductase

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

    Pandey, Amit V., E-mail: amit@pandeylab.org; Flueck, Christa E.; Mullis, Primus E.

    2010-09-24

    Research highlights: {yields} Mutations in POR identified from patients lead to reduced HO-1 activities. {yields} POR mutation Y181D affecting FMN binding results in total loss of HO-1 activity. {yields} POR mutations A287P, C569Y and V608F, lost 50-70% activity. {yields} Mutations in FAD binding domain, R457H, Y459H and V492E lost all HO-1 activity. {yields} POR polymorphisms P228L, R316W, G413S, A503V and G504R have normal activity. -- Abstract: Human heme oxygenase-1 (HO-1) carries out heme catabolism supported by electrons supplied from the NADPH through NADPH P450 reductase (POR, CPR). Previously we have shown that mutations in human POR cause a rare formmore » of congenital adrenal hyperplasia. In this study, we have evaluated the effects of mutations in POR on HO-1 activity. We used purified preparations of wild type and mutant human POR and in vitro reconstitution with purified HO-1 to measure heme degradation in a coupled assay using biliverdin reductase. Here we show that mutations in POR found in patients may reduce HO-1 activity, potentially influencing heme catabolism in individuals carrying mutant POR alleles. POR mutants Y181D, A457H, Y459H, V492E and R616X had total loss of HO-1 activity, while POR mutations A287P, C569Y and V608F lost 50-70% activity. The POR variants P228L, R316W and G413S, A503V and G504R identified as polymorphs had close to WT activity. Loss of HO-1 activity may result in increased oxidative neurotoxicity, anemia, growth retardation and iron deposition. Further examination of patients affected with POR deficiency will be required to assess the metabolic effects of reduced HO-1 activity in affected individuals.« less

  7. Balancing Immunity and Yield in Crop Plants.

    PubMed

    Ning, Yuese; Liu, Wende; Wang, Guo-Liang

    2017-12-01

    Crop diseases cause enormous yield losses and threaten global food[ED1] security. The use of highly resistant cultivars can effectively control plant diseases, but in crops, genetic immunity to disease often comes with an unintended reduction in growth and yield. Here, we review recent advances in understanding how nucleotide-binding domain, leucine-rich repeat (NLR) receptors and cell wall-associated kinase (WAK) proteins function in balancing immunity and yield. We also discuss the role of plant hormones and transcription factors in regulating the trade-offs between plant growth and immunity. Finally, we describe how a novel mechanism of translational control of defense proteins can enhance immunity without the reduction in fitness. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Yield loss assessment due to Alternaria blight and its management in linseed.

    PubMed

    Singh, R B; Singh, H K; Parmar, Arpita

    2014-04-01

    Field experiments were conducted during 2010-11 and 2011-12 to assess the yield losses due to Alternaria blight disease caused by Alternaria lini and A. linicola in recently released cultivars and their management with the integration of Trichoderma viride, fungicides and plant extract. Disease severity on leaves varied from 41.07% (Parvati) to 65.01% (Chambal) while bud damage per cent ranged between 23.56% (Shekhar) to 46.12% (T-397), respectively in different cultivars. Maximum yield loss of 58.44% was recorded in cultivar Neelum followed by Parvati (55.56%), Meera (55.56%) and Chambal (51.72%), respectively while minimum loss was recorded in Kiran (19.99%) and Jeevan (22.22%). Minimum mean disease severity (19.47%) with maximum disease control (69.74%) was recorded with the treatment: seed treatment (ST) with vitavax power (2 g kg(-1) seed) + 2 foliar sprays (FS) of Saaf (a mixture of carbendazim+mancozeb) 0.2% followed by ST with Trichoderma viride (4g kg(-1) seed) + 2 FS of Saaf (0.2%). Minimum bud damage (13.75%) with maximum control (60.94%) was recorded with treatment of ST with vitavax power+2 FS of propiconazole (0.2%). Maximum mean seed yield (1440 kg ha(-1)) with maximum net return (Rs. 15352/ha) and benefit cost ratio (1:11.04) was obtained with treatment ST with vitavax power + 2 FS of Neem leaf extract followed by treatment ST with vitavax power+2 FS of Saaf (1378 kg ha(-1)).

  9. Relationships between Soil and Levels of Meloidogyne incognita and Tobacco Yield and Quality.

    PubMed

    Barker, K R; Weeks, W W

    1991-01-01

    A 2-year study with six soils and four levels of Meloidogyne incognita in microplots was designed to determine the effects of these parameters on nematode activity and tobacco yield and quality. Key components under study were affected by soil, nematode level, and season (year-cultivar). In 1980, low initial nematode numbers (1,250) enhanced tobacco yield in Cecil clay loam, but caused slight to moderate yield losses in the other soils. Yield losses to M. incognita were generally greatest in sandy and muck soils. In 1980, regression analyses of the independent parameters Pi - clay-sand vs. yield gave an R(2) of 0.40. Examples of other coefficients of determination for yield vs. selected factors were root-necrosis index, 0.40; root-gall index, 0.18; root-gall index-cation exchange capacity (CEC), 0.34; root-necrosis index-CEC, 0.56; and root-necrosis index-sand-soil acidity-calcium, 0.62. In contrast, the R(2) for Pi alone versus yield in 1981 was 0.84. Soil also affected nematode reproduction with the greatest increases occurring in the sandy soils. In both years, low nematode numbers enhanced the synthesis of sugar in tobacco, whereas leaves from all other nematode treatments had low sugar levels. A low nicotine content was associated with nematode infection. Tobacco from sandy soils had a higher nicotine content than tobacco from clay soils.

  10. Genetic Architecture of Charcoal Rot (Macrophomina phaseolina) Resistance in Soybean Revealed Using a Diverse Panel

    USDA-ARS?s Scientific Manuscript database

    Charcoal rot disease caused by Macrophomina phaseolina is responsible for significant yield losses in soybean production. Among the methodologies available for controlling this disease, breeding for resistance is the most promising. Progress in breeding efforts has been slow due to the insufficient ...

  11. Complete sequence and diversity of a maize-associated Polerovirus in East Africa

    USDA-ARS?s Scientific Manuscript database

    Since 2011-2012, Maize lethal necrosis (MLN) has emerged in East Africa, causing massive yield loss and propelling research to identify viruses and virus populations present in maize. As expected, next generation sequencing (NGS) has revealed diverse and abundant viruses from the family Potyviridae,...

  12. Genetic analysis of genetic basis of a physiological disorder "straighthead’’ in rice (Oryza sativa L.)

    USDA-ARS?s Scientific Manuscript database

    Straighthead is a physiological disorder in rice that causes yield losses and is a serious threat to rice production worldwide. Identification of QTL conferring resistance will help develop resistant cultivars for straighthead control. We conducted linkage mapping to identify QTL involved with strai...

  13. A barley UDP-glucosyltransferase inactivates nivalenol and provides Fusarium head blight resistance in transgenic wheat

    USDA-ARS?s Scientific Manuscript database

    Fusarium Head Blight is a disease of cereal crops that causes severe yield losses and mycotoxin contamination of grain. The main causal pathogen, Fusarium graminearum, produces the trichothecene toxins deoxynivalenol or nivalenol as virulence factors. Nivalenol-producing isolates are most prevalent ...

  14. Root transformation of Glycine max with responsive promoters to nematode infection

    USDA-ARS?s Scientific Manuscript database

    The soybean cyst nematode (SCN; Heterodera glycines), an obligate parasite of plants, is the most damaging pathogen of soybean, causing $469 to $818 million in soybean yield losses annually in the United States. However, there are no soybean cultivars available that are resistant to all SCN populati...

  15. Host status of own-rooted Vitis vinifera varieties to Meloidogyne hapla

    USDA-ARS?s Scientific Manuscript database

    Plant-parasitic nematodes are microscopic soil worms that attack the roots of grape plants and cause yield loss. One of the most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards is Meloidogyne hapla, the northern root-knot nematode. The selection of plant...

  16. Effect of a combination of two rice herbicides on the cyanobacterium, Nostoc spongiaeforme

    USDA-ARS?s Scientific Manuscript database

    Cyanobacteria grow in California rice fields where they form large mats that may smoother seedlings or cause them to dislodge, resulting in yield loss. The most troublesome species is Nostoc spongiaeforme. It is very difficult to control using currently accepted methods, i.e., aerial applications of...

  17. Evidence for sexual reproduction in Venturia effusa, causal agent of pecan scab

    USDA-ARS?s Scientific Manuscript database

    Pecan scab caused by Venturia effusa is widespread across southwest USA and epidemics can result in catastrophic yield loss. Venturia effusa reproduces asexually during the active phase of the disease cycle (spring through summer) with no evidence of a sexual cycle. Yet, genetic diversity among popu...

  18. Determining yield loss caused by brown rust in production fields of sugarcane

    USDA-ARS?s Scientific Manuscript database

    Infections of Puccinia melanocephala, the causal agent of brown rust, appear on Louisiana sugarcane in the spring. Disease expression is usually limited to 2 to 3 months until temperatures exceed those favorable for spore production. The affected sugarcane is harvested 4 to 6 months after rust sympt...

  19. DIVERSITY OF PUCCINIA KUEHNII AND P. MELANOCEPHALA CAUSING RUST DISEASES ON BRAZILIAN SUGARCANE

    USDA-ARS?s Scientific Manuscript database

    Sugarcane industry in Brazil suffers yield loss due to brown rust (Puccinia melanocephala) since 1986 and orange rust (P. kuehnii) as recent as 2009. The main control measure for both diseases has been cultivar resistance. Nevertheless, recent onsets of orange rust on previously resistant cultivars ...

  20. Puccinia coronata f. sp. avenae: a threat to global oat production

    USDA-ARS?s Scientific Manuscript database

    Puccinia coronata f. sp. avenae causes crown rust disease in cultivated and wild oat. The significant yield losses inflicted by this pathogen makes crown rust the most devastating disease in the oat industry. P. coronata f. sp. avenae is a basidiomycete fungus with an obligate biotrophic lifestyle a...

  1. Managing Abiotic Factors of Compost to Increase Soilborne Disease Suppression

    ERIC Educational Resources Information Center

    Griffin, Deirdre E.

    2012-01-01

    Soilborne pathogens can devastate crops, causing economic losses for farmers due to reduced yields and expensive management practices. Fumigants and fungicides have harmful impacts on the surrounding environment and can be toxic to humans. Therefore, alternative methods of disease management are important. The disease suppressive abilities of…

  2. Status of Sugarcane yellow leaf virus and its impact in different progenies

    USDA-ARS?s Scientific Manuscript database

    Yellow leaf disease caused by Sugarcane yellow leaf virus (SCYLV) a Polerovirus is an important disease for sugarcane industries worldwide. High yield losses up to 50% were reported in susceptible varieties. Most of the commercial cultivars in Florida are infected with SCYLV; therefore, there is a ...

  3. Survey and identification of panicle blanking bacteria in Arkansas

    USDA-ARS?s Scientific Manuscript database

    Outbreaks of bacterial panicle blight (BPB) of rice in recent past years have resulted in severe yield losses in the Southern United States including Arkansas. Bacterial species, Burkholderia glumae was identified as the main causative agent among others causing BPB in rice. The symptoms of BPB inc...

  4. What lies beneath, unraveling the mysteries of Rhizoctonia and Pythium

    USDA-ARS?s Scientific Manuscript database

    Washington wheat and barley growers have long recognized that the soil-borne fungal pathogens Rhizoctonia and Pythium cause root rot, stunting and poor emergence and can chip away at yield, resulting in annual losses of 10 percent or more. Since several of these Rhizoctonia and Pythium species attac...

  5. Stemphylium leaf spot of parsley in California caused by Stemphylium vesicarium

    USDA-ARS?s Scientific Manuscript database

    From 2009 through 2011, a previously undescribed disease occurred on commercial parsley in coastal (Ventura County) California. Symptoms of the disease consisted of circular to oval, tan to brown leaf spots and resulted in loss of crop quality and hence reduced yields. A fungus was consistently isol...

  6. Compartmentalized gene regulatory network of the pathogenic fungus Fusarium graminearum

    USDA-ARS?s Scientific Manuscript database

    Head blight caused by Fusarium graminearum (Fg) is a major limiting factor of wheat production with both yield loss and mycotoxin contamination. Here we report a model for global Fg gene regulatory networks (GRNs) inferred from a large collection of transcriptomic data using a machine-learning appro...

  7. Detection of novel QTLs for foxglove aphid resistance in soybean

    USDA-ARS?s Scientific Manuscript database

    Foxglove aphid, Aulacorthum solani (Kaltenbach), is a Hemipteran insect that infected a wide variety of plants worldwide and caused serious yield losses in crops. The objective of this study was to identify the putative QTL for foxglove aphid resistance in wild soybean, PI 366121, (Glycine soja Sieb...

  8. Genome-wide association mapping of anthracnose (Collectotrichum sublineolun) resistance in U.S. sorghum association panel

    USDA-ARS?s Scientific Manuscript database

    The productivity and profitability of sorghum [Sorghum bicolor (L.) Moench] is reduced by susceptibility to fungal diseases such as anthracnose, which causes yield loss of both grain and biomass. A limited number of resistant accessions are present in temperate adapted germplasm, while resistant sou...

  9. Fungicide rotation schemes for managing Phytophthora fruit rot of watermelon across southeastern United States

    USDA-ARS?s Scientific Manuscript database

    Southeastern states produce about 50% of the watermelons in the United States (U.S.) where conditions are optimal for development of Phytophthora fruit rot prevail. Phytophthora fruit rot significantly limits watermelon production by causing serious yield losses to growers before and after harvest. ...

  10. Genotypic variability for tuber yield, biomass, and drought tolerance in Jerusalem artichoke germplasm

    USDA-ARS?s Scientific Manuscript database

    Jerusalem artichoke could be an alternative feedstock for bioenergy during times when there are shortages of other raw materials for the ethanol industry. However, insufficient water under rainfed conditions is a major cause of Jerusalem artichoke losses. Genetic variation for drought tolerance is...

  11. Variability associated with screening for common scab and verticillium wilt in potato

    USDA-ARS?s Scientific Manuscript database

    Common Scab (CS) and Verticillium Wilt (VW) are caused by the soilborne bacteria Streptomyces scabies, and fungi, Verticillium dahliae and V. albo-atrum, respectively, in potato (Solanum tuberosum). Both diseases result in biological and/or marketable yield loss and are tested in fields with high di...

  12. Iron deficiency in plants: An insight from proteomic approaches

    USDA-ARS?s Scientific Manuscript database

    Iron (Fe) deficiency chlorosis is a major nutritional disorder for crops growing in calcareous soils, and causes decreases in vegetative growth as well as marked yield and quality losses. With the advances in mass spectrometry techniques, a substantial body of knowledge has arisen on the changes in ...

  13. A threshold-based weather model for predicting stripe rust infection in winter wheat

    USDA-ARS?s Scientific Manuscript database

    Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) is a major threat in most wheat growing regions worldwide, with potential to inflict regular yield losses when environmental conditions are favorable. We propose a threshold-based disease-forecasting model using a stepwise modeling...

  14. Conditional deletion of Dicer in vascular smooth muscle cells leads to the developmental delay and embryonic mortality

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

    Pan, Yaoqian; Center for Cancer Research, University of Tennessee Health Science Center, Memphis, TN 38163; Balazs, Louisa

    2011-05-13

    Highlights: {yields} Deletion of Dicer in vascular smooth muscle cells(VSMCs) leads to embryonic mortality. {yields} Loss of Dicer in VSMCs leads to developmental delay. {yields} Loss of Dicer in VSMCs leads to hemorrhage in various organs including brain, skin and liver. {yields} Loss of Dicer in VSMCs leads to vascular wall remodeling. {yields} Loss of Dicer in VSMCs dysregulates the expression of miRNA and VSMC marker genes. -- Abstract: Dicer is a RNAase III enzyme that cleaves double stranded RNA and generates small interfering RNA (siRNA) and microRNA (miRNA). The goal of this study is to examine the role ofmore » Dicer and miRNAs in vascular smooth muscle cells (VSMCs). We deleted Dicer in VSMCs of mice, which caused a developmental delay that manifested as early as embryonic day E12.5, leading to embryonic death between E14.5 and E15.5 due to extensive hemorrhage in the liver, brain, and skin. Dicer KO embryos showed dilated blood vessels and a disarray of vascular architecture between E14.5 and E15.5. VSMC proliferation was significantly inhibited in Dicer KOs. The expression of VSMC marker genes were significantly downregulated in Dicer cKO embryos. The vascular structure of the yolk sac and embryo in Dicer KOs was lost to an extent that no blood vessels could be identified after E15.5. Expression of most miRNAs examined was compromised in VSMCs of Dicer KO. Our results indicate that Dicer is required for vascular development and regulates vascular remodeling by modulating VSMC proliferation and differentiation.« less

  15. USSR Report Agriculture No. 1399.

    DTIC Science & Technology

    1983-09-15

    from inflammation of the udder. It is easy to estimate that for an average milk yield of 2,054 kilograms, the loss for one mastitis cow is 400...important and vital one. Thus it is apparent that milk losses in the Urals caused by injury to the udders, the cow going dry and mastitis amount to...the cow from drying up and eliminate mastitis and if we maintain the cows at the required state of nourishment, then each year we should be able to

  16. Hyperspectral sensing to detect the impact of herbicide drift on cotton growth and yield

    NASA Astrophysics Data System (ADS)

    Suarez, L. A.; Apan, A.; Werth, J.

    2016-10-01

    Yield loss in crops is often associated with plant disease or external factors such as environment, water supply and nutrient availability. Improper agricultural practices can also introduce risks into the equation. Herbicide drift can be a combination of improper practices and environmental conditions which can create a potential yield loss. As traditional assessment of plant damage is often imprecise and time consuming, the ability of remote and proximal sensing techniques to monitor various bio-chemical alterations in the plant may offer a faster, non-destructive and reliable approach to predict yield loss caused by herbicide drift. This paper examines the prediction capabilities of partial least squares regression (PLS-R) models for estimating yield. Models were constructed with hyperspectral data of a cotton crop sprayed with three simulated doses of the phenoxy herbicide 2,4-D at three different growth stages. Fibre quality, photosynthesis, conductance, and two main hormones, indole acetic acid (IAA) and abscisic acid (ABA) were also analysed. Except for fibre quality and ABA, Spearman correlations have shown that these variables were highly affected by the chemical. Four PLS-R models for predicting yield were developed according to four timings of data collection: 2, 7, 14 and 28 days after the exposure (DAE). As indicated by the model performance, the analysis revealed that 7 DAE was the best time for data collection purposes (RMSEP = 2.6 and R2 = 0.88), followed by 28 DAE (RMSEP = 3.2 and R2 = 0.84). In summary, the results of this study show that it is possible to accurately predict yield after a simulated herbicide drift of 2,4-D on a cotton crop, through the analysis of hyperspectral data, thereby providing a reliable, effective and non-destructive alternative based on the internal response of the cotton leaves.

  17. Chlorhexidine Prevents Root Dentine Mineral Loss and Fracture Caused by Calcium Hydroxide over Time

    PubMed Central

    Thomaz, Érika Bárbara Abreu Fonseca; Lima, Darlon Martins; Bauer, José

    2017-01-01

    Purpose. To evaluate the mineral ion loss of root dentine after treatment with 2% chlorhexidine solution (CHX) and to compare its yield and flexural strength (fs) after exposure to calcium hydroxide [Ca(OH)2]. Materials and Methods. Dentine bars (DB) were made from 90 roots of bovine incisors and randomized into three groups: GControl: distilled/deionized water (DDW), GNaOCl: 2.5% sodium hypochlorite + 17% EDTA, and GCHX: CHX + DDW. The release of phosphate (PO4) and calcium (Ca) ions was measured by spectrophotometry. The DB were exposed to Ca(OH)2 paste for 0, 30, 90, and 180 days. DB were subjected to the three-point bending test to obtain yield and fs values. The fracture patterns were evaluated (20x). Data were analyzed using Kruskal-Wallis and Dunn's post hoc tests or one- and two-way ANOVA followed by Tukey's post hoc test (α = 0.05). Results. GCHX showed lower PO43− and Ca2+ ionic release than GNaOCl (p < 0.001). For yield and fs, GCHX > GNaOCl in all periods (p < 0.001), except for yield strength values on 90 days (p = 0.791). A larger frequency of vertical fractures was observed in GNaOCl and that of oblique fractures in GCHX (p < 0.05). Conclusions. CHX prevented PO43− and Ca2+ loss and showed a tendency to preserve the yield and fs of root dentine over time following exposure to Ca(OH)2 paste. PMID:28539937

  18. [Effects of controlled release nitrogen fertilizer application on dry matter accumulation and nitrogen balance of summer maize].

    PubMed

    Si, Dong-Xia; Cui, Zhen-Ling; Chen, Xin-Ping; Lü, Fu-Tang

    2014-06-01

    Effects of four controlled release nitrogen (N) fertilizers, including two kinds of polyester coated urea (Ncau, CRU) and phosphate (NhnP) and humic acid (NhnF) coated urea on assimilates accumulation and nitrogen balance of summer maize were investigated in a mode of one-time fertilization at the regional N recommended rate. The results showed that the N release curves of the two controlled release fertilizers CRU and Ncau matched well with the summer maize N uptake. Compared with the regional N recommendation rate, CRU could increase maize yield by 4.2% and Ncau could maintain the same yield level. CRU significantly increased the dry matter accumulation rate after anthesis of summer maize, but Ncau markedly increased the dry matter accumulated ratio before anthesis. Meanwhile, CRU could reduce the apparent N losses by 19 kg N x hm(-2) in the case of large precipitation. However, NhnF and NhnP caused the yield losses by 0.1%-8.9%, and enhanced the apparent N losses. Therefore, both CRU and Ncau with one-time fertilization could be a simplified alternative to the "total control, staging regulation" fertilization technique at the regional N recommended rate for summer maize production.

  19. Reduction in hepatic drug metabolizing CYP3A4 activities caused by P450 oxidoreductase mutations identified in patients with disordered steroid metabolism

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

    Flueck, Christa E.; Mullis, Primus E.; Pandey, Amit V., E-mail: amit@pandeylab.org

    2010-10-08

    Research highlights: {yields} Cytochrome P450 3A4 (CYP3A4), metabolizes 50% of drugs in clinical use and requires NADPH-P450 reductase (POR). {yields} Mutations in human POR cause congenital adrenal hyperplasia from diminished activities of steroid metabolizing P450s. {yields} We are reporting that mutations in POR may reduce CYP3A4 activity. {yields} POR mutants Y181D, A457H, Y459H, V492E and R616X lost 99%, while A287P, C569Y and V608F lost 60-85% CYP3A4 activity. {yields} Reduction of CYP3A4 activity may cause increased risk of drug toxicities/adverse drug reactions in patients with POR mutations. -- Abstract: Cytochrome P450 3A4 (CYP3A4), the major P450 present in human liver metabolizesmore » approximately half the drugs in clinical use and requires electrons supplied from NADPH through NADPH-P450 reductase (POR, CPR). Mutations in human POR cause a rare form of congenital adrenal hyperplasia from diminished activities of steroid metabolizing P450s. In this study we examined the effect of mutations in POR on CYP3A4 activity. We used purified preparations of wild type and mutant human POR and in vitro reconstitution with purified CYP3A4 to perform kinetic studies. We are reporting that mutations in POR identified in patients with disordered steroidogenesis/Antley-Bixler syndrome (ABS) may reduce CYP3A4 activity, potentially affecting drug metabolism in individuals carrying mutant POR alleles. POR mutants Y181D, A457H, Y459H, V492E and R616X had more than 99% loss of CYP3A4 activity, while POR mutations A287P, C569Y and V608F lost 60-85% activity. Loss of CYP3A4 activity may result in increased risk of drug toxicities and adverse drug reactions in patients with POR mutations.« less

  20. Mathematical model of sediment and solute transport along slope land in different rainfall pattern conditions

    PubMed Central

    Tao, Wanghai; Wu, Junhu; Wang, Quanjiu

    2017-01-01

    Rainfall erosion is a major cause of inducing soil degradation, and rainfall patterns have a significant influence on the process of sediment yield and nutrient loss. The mathematical models developed in this study were used to simulate the sediment and nutrient loss in surface runoff. Four rainfall patterns, each with a different rainfall intensity variation, were applied during the simulated rainfall experiments. These patterns were designated as: uniform-type, increasing-type, increasing- decreasing -type and decreasing-type. The results revealed that changes in the rainfall intensity can have an appreciable impact on the process of runoff generation, but only a slight effect on the total amount of runoff generated. Variations in the rainfall intensity in a rainfall event not only had a significant effect on the process of sediment yield and nutrient loss, but also the total amount of sediment and nutrient produced, and early high rainfall intensity may lead to the most severe erosion and nutrient loss. In this study, the calculated data concur with the measured values. The model can be used to predict the process of surface runoff, sediment transport and nutrient loss associated with different rainfall patterns. PMID:28272431

  1. Maize streak virus: an old and complex 'emerging' pathogen.

    PubMed

    Shepherd, Dionne N; Martin, Darren P; Van Der Walt, Eric; Dent, Kyle; Varsani, Arvind; Rybicki, Edward P

    2010-01-01

    Maize streak virus (MSV; Genus Mastrevirus, Family Geminiviridae) occurs throughout Africa, where it causes what is probably the most serious viral crop disease on the continent. It is obligately transmitted by as many as six leafhopper species in the Genus Cicadulina, but mainly by C. mbila Naudé and C. storeyi. In addition to maize, it can infect over 80 other species in the Family Poaceae. Whereas 11 strains of MSV are currently known, only the MSV-A strain is known to cause economically significant streak disease in maize. Severe maize streak disease (MSD) manifests as pronounced, continuous parallel chlorotic streaks on leaves, with severe stunting of the affected plant and, usuallly, a failure to produce complete cobs or seed. Natural resistance to MSV in maize, and/or maize infections caused by non-maize-adapted MSV strains, can result in narrow, interrupted streaks and no obvious yield losses. MSV epidemiology is primarily governed by environmental influences on its vector species, resulting in erratic epidemics every 3-10 years. Even in epidemic years, disease incidences can vary from a few infected plants per field, with little associated yield loss, to 100% infection rates and complete yield loss. The only virus species known to cause MSD is MSV, the type member of the Genus Mastrevirus in the Family Geminiviridae. In addition to the MSV-A strain, which causes the most severe form of streak disease in maize, 10 other MSV strains (MSV-B to MSV-K) are known to infect barley, wheat, oats, rye, sugarcane, millet and many wild, mostly annual, grass species. Seven other mastrevirus species, many with host and geographical ranges partially overlapping those of MSV, appear to infect primarily perennial grasses. MSV and all related grass mastreviruses have single-component, circular, single-stranded DNA genomes of approximately 2700 bases, encapsidated in 22 x 38-nm geminate particles comprising two incomplete T = 1 icosahedra, with 22 pentameric capsomers composed of a single 32-kDa capsid protein. Particles are generally stable in buffers of pH 4-8. In infected maize plants, streak disease initially manifests as minute, pale, circular spots on the lowest exposed portion of the youngest leaves. The only leaves that develop symptoms are those formed after infection, with older leaves remaining healthy. As the disease progresses, newer leaves emerge containing streaks up to several millimetres in length along the leaf veins, with primary veins being less affected than secondary or tertiary veins. The streaks are often fused laterally, appearing as narrow, broken, chlorotic stripes, which may extend over the entire length of severely affected leaves. Lesion colour generally varies from white to yellow, with some virus strains causing red pigmentation on maize leaves and abnormal shoot and flower bunching in grasses. Reduced photosynthesis and increased respiration usually lead to a reduction in leaf length and plant height; thus, maize plants infected at an early stage become severely stunted, producing undersized, misshapen cobs or giving no yield at all. Yield loss in susceptible maize is directly related to the time of infection: infected seedlings produce no yield or are killed, whereas plants infected at later times are proportionately less affected. Disease avoidance can be practised by only planting maize during the early season when viral inoculum loads are lowest. Leafhopper vectors can also be controlled with insecticides such as carbofuran. However, the development and use of streak-resistant cultivars is probably the most effective and economically viable means of preventing streak epidemics. Naturally occurring tolerance to MSV (meaning that, although plants become systemically infected, they do not suffer serious yield losses) has been found, which has primarily been attributed to a single gene, msv-1. However, other MSV resistance genes also exist and improved resistance has been achieved by concentrating these within individual maize genotypes. Whereas true MSV immunity (meaning that plants cannot be symptomatically infected by the virus) has been achieved in lines that include multiple small-effect resistance genes together with msv-1, it has proven difficult to transfer this immunity into commercial maize genotypes. An alternative resistance strategy using genetic engineering is currently being investigated in South Africa. http://www.mcb.uct.ac.za/MSV/mastrevirus.htm; http://www.danforthcenter.org/iltab/geminiviridae/geminiaccess/mastrevirus/Mastrevirus.htm.

  2. Techniques for Measuring Low Earth Orbital Atomic Oxygen Erosion of Polymers

    NASA Technical Reports Server (NTRS)

    deGroh, Kim K.; Banks, Bruce A.; Demko, Rikako

    2002-01-01

    Polymers such as polyimide Kapton and Teflon FEP (fluorinated ethylene propylene) are commonly used spacecraft materials due to their desirable properties such as flexibility, low density, and in the case of FEP, a low solar absorptance and high thermal emittance. Polymers on the exterior of spacecraft in the low Earth orbit (LEO) environment are exposed to energetic atomic oxygen. Atomic oxygen reaction with polymers causes erosion, which is a threat to spacecraft durability. It is therefore important to understand the atomic oxygen erosion yield (E, the volume loss per incident oxygen atom) of polymers being considered in spacecraft design. The most common technique for determining E is through mass loss measurements. For limited duration exposure experiments, such as shuttle experiments, where the atomic oxygen fluence is often so low that mass loss measurements can not produce acceptable uncertainties, recession measurements based on atomic force microscopy analyses can be used. Equally necessary to knowing the mass loss or recession depth for determining the erosion yield of polymers is the knowledge of the atomic oxygen fluence that the polymers were exposed to in space. This paper discusses the procedures and relevant issues for mass loss and recession depth measurements for passive atomic oxygen erosion yield characterization of polymers, along with techniques for active atomic oxygen fluence and erosion characterization. One active atomic oxygen erosion technique discussed is a new technique based on optical measurements. Details including the use of both semi-transparent and opaque polymers for active erosion measurement are reviewed.

  3. Impact of thermal processing on sulforaphane yield from broccoli ( Brassica oleracea L. ssp. italica).

    PubMed

    Wang, Grace C; Farnham, Mark; Jeffery, Elizabeth H

    2012-07-11

    In broccoli, sulforaphane forms when the glucosinolate glucoraphanin is hydrolyzed by the endogenous plant thiohydrolase myrosinase. A myrosinase cofactor directs hydrolysis away from the formation of bioactive sulforaphane and toward an inactive product, sulforaphane nitrile. The cofactor is more heat sensitive than myrosinase, presenting an opportunity to preferentially direct hydrolysis toward sulforaphane formation through regulation of thermal processing. Four broccoli cultivars were microwave heated, boiled, or steamed for various lengths of time. Production of nitrile during hydrolysis of unheated broccoli varied among cultivars from 91 to 52% of hydrolysis products (Pinnacle > Marathon > Patriot > Brigadier). Boiling and microwave heating caused an initial loss of nitrile, with a concomitant increase in sulforaphane, followed by loss of sulforaphane, all within 1 min. In contrast, steaming enhanced sulforaphane yield between 1.0 and 3.0 min in all but Brigadier. These data are proof of concept that steaming for 1.0-3.0 min provides less nitrile and more sulforaphane yield from a broccoli meal.

  4. Characterizing distributions of surface ozone and its impact on grain production in China, Japan and South Korea: 1990 and 2020

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoping; Mauzerall, Denise L.

    Using an integrated assessment approach, we evaluate the impact that surface O 3 in East Asia had on agricultural production in 1990 and is projected to have in 2020. We also examine the effect that emission controls and the enforcement of environmental standards could have in increasing grain production in China. We find that given projected increases in O 3 concentrations in the region, East Asian countries are presently on the cusp of substantial reductions in grain production. Our conservative estimates, based on 7- and 12-h mean (M7 or M12) exposure indices, show that due to O 3 concentrations in 1990 China, Japan and South Korea lost 1-9% of their yield of wheat, rice and corn and 23-27% of their yield of soybeans, with an associated value of 1990US 3.5, 1.2 and 0.24 billion, respectively. In 2020, assuming no change in agricultural production practices and again using M7 and M12 exposure indices, grain loss due to increased levels of O 3 pollution is projected to increase to 2-16% for wheat, rice and corn and 28-35% for soybeans; the associated economic costs are expected to increase by 82%, 33%, and 67% in 2020 over 1990 for China, Japan and South Korea, respectively. For most crops, the yield losses in 1990 based on SUM06 or W126 exposure indices are lower than yield losses estimated using M7 or M12 exposure indices in China and Japan but higher in South Korea; in 2020, the yield losses based on SUM06 or W126 exposure indices are substantially higher for all crops in all three countries. This is primarily due to the nature of the cumulative indices which weight elevated values of O 3 more heavily than lower values. Chinese compliance with its ambient O 3 standard in 1990 would have had a limited effect in reducing the grain yield loss caused by O 3 exposure, resulting in only US 0.2 billion of additional grain revenues, but in 2020 compliance could reduce the yield loss by one third and lead to an increase of US$ 2.6 (M7 or M12) -27 (SUM06) billion in grain revenues. We conclude that East Asian countries may have tremendous losses of crop yields in the near future due to projected increases in O 3 concentrations. They likely could achieve substantial increases in future agricultural production through reduction of surface O 3 concentrations and/or use of O 3 resistant crop cultivars.

  5. Progressive sensorineural hearing loss, subjective tinnitus and vertigo caused by elevated blood lipids.

    PubMed

    Pulec, J L; Pulec, M B; Mendoza, I

    1997-10-01

    The otologist frequently sees patients with progressive sensorineural hearing loss, subjective aural tinnitus and vertigo with no apparent cause. Elevated blood lipids may be a cause of inner ear malfunction on a biochemical basis. To establish the true incidence of this condition, all new patients (4,251) seen during an eight-year period were evaluated; of these, 2,332 patients had complaints of inner ear disease. All had a complete neurotologic examination, appropriate audiometric and vestibular studies and imaging, and blood tests including lipid phenotype studies. Hyperlipoproteinemia was found in 120 patients (5.1%). Most patients were found to be overweight and had additional coexisting conditions such as diabetes mellitus. Treatment with vasodilators and a 500-calorie, high-protein, low-carbohydrate diet yielded improvement of symptoms in 83% of patients within five months of initiation of treatment.

  6. Virulence variations of Puccinia striiformis f. sp. tritici isolates sexually produced on Berberis spp. under natural conditions in China

    USDA-ARS?s Scientific Manuscript database

    The stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), frequently causes significant yield losses in China, due to rapid development of new races that overcome resistance in wheat cultivars. Indirect evidence suggests that sexual reproduction occurs in the Pst population in China, but...

  7. RNA-seq analysis reveals genetic response and tolerance mechanisms to ozone exposure in soybean

    USDA-ARS?s Scientific Manuscript database

    Oxidative stress caused by ground level ozone is a major contributor to yield loss in a number of important crop plants. Soybean (Glycine max) is especially ozone sensitive, and research into its response to oxidative stress is limited. To better understand the genetic response in soybean to oxida...

  8. First report of the Soybean Cyst Nematode, Heterodera glycines, in New York

    USDA-ARS?s Scientific Manuscript database

    The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is the most damaging pathogen of soybean (Glycine max (L.) Merr.), causing more than $1 billion in yield losses annually in the United States (Koenning and Wrather 2010). The SCN distribution map updated in 2014 showed that SCN were dete...

  9. Wheat streak mosaic virus resistance in eight wheat germplasm lines

    USDA-ARS?s Scientific Manuscript database

    Wheat Streak Mosaic Virus (WSMV) disease is an important disease in wheat. Use of resistant cultivars is the most effective approach to reduce the yield losses caused by the disease. To identify new sources of resistance to WSMV, eight resistant wheat lines that were selected based on the results fr...

  10. Novel sources of leaf rust resistance in winter wheat

    USDA-ARS?s Scientific Manuscript database

    Leaf rust is one of the most widespread diseases of wheat, causing significant yield losses. More than 70 leaf rust resistance genes have been reported, but most of them have lost their effectiveness in the southern Great Plains of the USA. Thus continuous search for new sources of resistance is e...

  11. Postulation and mapping of seedling stripe rust resistance genes in Ethiopian bread wheat cultivars

    USDA-ARS?s Scientific Manuscript database

    Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide. In Ethiopia, grain yield loss in wheat cultivars ranges from 30 to 69%. The use of resistant cultivars is the most economical and environmentally friendly method of controlling ...

  12. Impact of grapevine (Vitis vinifera) varieties on reproduction of the northern root-knot nematode (Meloidogyne hapla)

    USDA-ARS?s Scientific Manuscript database

    Plant-parasitic nematodes are microscopic soil worms that attack the roots of grape plants and cause yield loss. One of the most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards is Meloidogyne hapla, the northern root-knot nematode. The selection of plant...

  13. Grain dormancy and light quality effects on germination in the model grass Brachypodium distachyon

    USDA-ARS?s Scientific Manuscript database

    Lack of seed dormancy in cereal crops such as barley and wheat is a common problem affecting farming areas around the world, causing losses in yield and quality due to pre-harvest sprouting. Control of seed dormancy has been investigated extensively using various approaches in different species incl...

  14. Assembly and annotation of the wildrice transcriptome challenged by Cochliobolus miyabeanus, the fungal brown spot pathogen

    USDA-ARS?s Scientific Manuscript database

    American wildrice (Zizania palustris) is an aquatic cereal that is harvested from natural stands and commercial paddies for its gourmet grain. Fungal brown spot (FBS), caused by Cochliobolus miyabeanus, is the most important disease that inflicts annual yield losses in this crop. The development of ...

  15. The distribution of peach scab lesions on the surface of diseased peaches

    USDA-ARS?s Scientific Manuscript database

    Peach canker (Fusicladium effusum) can cause yield loss of peach and results in rejection of fruit for fresh sale. Developing peach fruit become infected through splash dispersed inoculum. The aim of this study was to describe and quantify the distribution of lesions on the fruit surface, and prov...

  16. Cone Analysis of Southern Pines - A Guidebook

    Treesearch

    D.L. Bramlett; E.W. Belcher; G.L. DeBarr; G.D. Hertel; Robert P. Karrfalt; C.W. Lantz; T. Miller; K.D. Ware; H.O. Yates

    1977-01-01

    Southern pine tree improvement programs require an ample supply of improved seeds, but productron from southern pine seed orchards has often been disappointing. If high productron is to be malntained yields must be monitored and causes of seed losses must be identified. Techniques for determining seed efficiency were first used for red pine, Pinus resinosa...

  17. Examining the transcriptional response in wheat Fhb1 near-isogenic lines to Fusarium graminearum infection and deoxynivalenol treatment

    USDA-ARS?s Scientific Manuscript database

    Fusarium Head Blight (FHB) is a disease caused by the fungal pathogen Fusarium graminearum that affects wheat and other small grain cereals and can lead to severe yield loss and reduction in grain quality. Trichothecene mycotoxins, such as deoxynivalenol (DON), accumulate during infection and increa...

  18. Relationship between piercing-sucking insect control and internal lint and seed rot in Southeastern cotton (Gossypium hirsutum)

    USDA-ARS?s Scientific Manuscript database

    In 1999 crop consultants scouting for stink bugs (several Hemiptera spp.) in South Carolina discovered a formerly unobserved seed rot of cotton that caused yield losses ranging from 10 to 15% in certain fields. The same symptoms were subsequently reported in fields throughout the southeastern Cotto...

  19. Implements and cultivation frequency to improve in-row weed control in organic peanut production

    USDA-ARS?s Scientific Manuscript database

    Weed control in organic peanut production is difficult and costly, which limits expansion of the production system. Sweep cultivation in the row middles is effective, but weeds remain in the crop row causing yield loss. Research trials were conducted in Tifton, GA to evaluate implements and freque...

  20. Field evaluation of three sources of genetic resistance to sudden death syndrome of soybean

    USDA-ARS?s Scientific Manuscript database

    Sudden death syndrome (SDS) of soybean [Glycine max (L.) Merrill] is a disease that causes yield loss in soybean growing regions across the USA and worldwide. While several quantitative trait loci (QTL) for SDS resistance have been mapped, studies to further evaluate these QTL are limited. The objec...

  1. Isolation of nematode DNA from 100 grams of soil using Fe3O4 super paramagnetic nanoparticles

    USDA-ARS?s Scientific Manuscript database

    Soilborne plant-parasitic nematodes cause losses through yield reductions and damage to a broad range of crops worldwide. Control of plant-parasitic nematodes often relies on application of fumigants or non-fumigant nematicides without knowledge of the presence of the nematodes or population densiti...

  2. Sequence variation and recognition specificity of the avirulence gene AvrPiz-t in Magnaporthe oryzae field populations

    USDA-ARS?s Scientific Manuscript database

    Magnaporthe oryzae, the rice blast pathogen, causes significant annual yield loss of rice worldwide. Currently, the most effective disease control approach is deployment of host resistance through introduction of resistance (R) genes into elite cultivars. The function of each R gene relies on the sp...

  3. Development of a sweet cherry pepper line with resistance to the southern root-knot nematode Meloidogyne incognita

    USDA-ARS?s Scientific Manuscript database

    The southern root-knot nematode (Meloidogyne incognita) is a major pathogen of pepper (Capsicum spp.), causing significant yield losses in heavily infected plants. The N-gene confers resistance to M. incognita, and has been successfully used to mitigate nematode damage in specific pepper varieties f...

  4. Sprinkling to prevent decay in decked western hemlock logs.

    Treesearch

    Ernest Wright; A.C. Knauss; R.M. Lindgren

    1959-01-01

    Decay developing in decked western hemlock (Tsuga heterophylla) has caused considerable loss in pulp yields in the Pacific Northwest. The Oregon Pulp and Paper Co., which commonly decks hemlock logs through one summer and occasionally through two summers, cooperated with the Pacific Northwest Forest and Range Experiment Station in a study to...

  5. Stunted patches in onion bulb crops in Oregon and Washington: Etiology and yield loss

    USDA-ARS?s Scientific Manuscript database

    Onion stunting caused by Rhizoctonia spp. is an important soilborne disease in the Columbia Basin of Oregon and Washington. From 2010 to 2013, 251 isolates of Rhizoctonia or Rhizoctonia-like spp. were obtained from soil and onion plant samples collected from Oregon and Washington. Sequence analysis ...

  6. Screening of sorghum lines against long smut and grain mold pathogens

    USDA-ARS?s Scientific Manuscript database

    Long smut infection is severe in the drier regions of Africa and Asia; whereas, grain mold is the most important widespread complex disease where sorghum is grown worldwide. Both fungal diseases cause significant losses in grain yield and quality. Long smut has not yet been observed in the United ...

  7. Wheat Rusts in the United States in 2007

    USDA-ARS?s Scientific Manuscript database

    In 2007 90% of wheat stem rust races were QFC and 10% were RCRS Both races are relatively avirulent to wheat cultiars grown in the U.S. Wheat stem rust occurred in scattered locations on research plots of susceptible wheat cultivars in 2007, and did not cause yield loss. Wheat leaf rust was widespr...

  8. Efficacy of fungicide combinations, phosphoric acid, and plant extract from stinging nettle on potato late blight management and tuber yield

    USDA-ARS?s Scientific Manuscript database

    Late blight, caused by Phytophthora infestans is a major constraint to potato production. Inadequate management of the disease has often resulted in heavy losses in various production regions. We assessed the efficacy of fungicides, phosphoric acid, and stinging nettle plant extract combinations for...

  9. Calcium may help decrease rice straighthead in a silt loam soil

    USDA-ARS?s Scientific Manuscript database

    Straighthead is a physiological disease in rice which causes blanking of the panicle and can result in complete yield loss. Using the US cultivar Cocodrie and three breeding lines, 8-18, 8-9 and 12-38, we tested the effect of Calcium (Ca) application on straighthead symptoms in the greenhouse. Three...

  10. Stripe rust epidemiological regions, virulence dynamics, pathogen reproduction modes, yield losses, forecasting models, and management in the United States

    USDA-ARS?s Scientific Manuscript database

    Stripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases in the United States. Epidemiological regions were determined based on epidemic patterns, cropping systems, geographic barriers, weather patterns, and inoculum exchanges. Areas where Ps...

  11. The Role of Faculty Validation in Influencing Online Students' Intent to Persist

    ERIC Educational Resources Information Center

    Arshad-Snyder, Siti Arfah

    2017-01-01

    In higher education, students who withdraw from college before graduating face and trigger a number of undesirable consequences, such as difficulty finding professional employment, risking default on student loans, causing loss of potential revenue to academic institutions, and yielding a negative return on society's expenditures for college…

  12. Regional differences in the composition of Fusarium head blight pathogens and mycotoxins associated with wheat in Mexico

    USDA-ARS?s Scientific Manuscript database

    Fusarium Head Blight (FHB) is a destructive disease of small grain cereals and a major food safety concern. Epidemics result in substantial yield losses, reduction in crop quality, and contamination of grains with trichothecenes and other mycotoxins. A number of different fusaria can cause FHB, and ...

  13. Neonicotinoid Seed Treatments and Foliar Sprays on Sugarbeet for Control of Severe Curly Top

    USDA-ARS?s Scientific Manuscript database

    Sugarbeet production in semiarid regions is hindered by yield loss caused with Beet severe curly top virus and other closely related species vectored by the beet leafhopper. In 2010, a study was established to investigate the level of control from seed treatments and supplemental foliar insecticide...

  14. Management of curly top in sugarbeet with seed and foliar insecticides

    USDA-ARS?s Scientific Manuscript database

    Curly top in sugarbeet can result in severe yield losses and is caused by Beet severe curly top virus (BSCTV) and other closely related Curtovirus spp. which are vectored by the beet leafhopper. Neonicotinoid seed treatments (Cruiser, NipsIt, and Poncho) have been shown to be an effective supplemen...

  15. Management of curly top in sugar beet with seed and foliar insecticides

    USDA-ARS?s Scientific Manuscript database

    Curly top in sugar beet can result in severe yield losses and is caused by Beet severe curly top virus (BSCTV) and other closely related Curtovirus spp. which are vectored by the beet leafhopper. Neonicotinoid seed treatments (Cruiser, NipsIt, and Poncho) have been shown to be an effective suppleme...

  16. Heat waves imposed during early pod development in soybean (Glycine max) cause significant yield loss despite a rapid recovery from oxidative stress.

    PubMed

    Siebers, Matthew H; Yendrek, Craig R; Drag, David; Locke, Anna M; Rios Acosta, Lorena; Leakey, Andrew D B; Ainsworth, Elizabeth A; Bernacchi, Carl J; Ort, Donald R

    2015-08-01

    Heat waves already have a large impact on crops and are predicted to become more intense and more frequent in the future. In this study, heat waves were imposed on soybean using infrared heating technology in a fully open-air field experiment. Five separate heat waves were applied to field-grown soybean (Glycine max) in central Illinois, three in 2010 and two in 2011. Thirty years of historical weather data from Illinois were analyzed to determine the length and intensity of a regionally realistic heat wave resulting in experimental heat wave treatments during which day and night canopy temperatures were elevated 6 °C above ambient for 3 days. Heat waves were applied during early or late reproductive stages to determine whether and when heat waves had an impact on carbon metabolism and seed yield. By the third day of each heat wave, net photosynthesis (A), specific leaf weight (SLW), and leaf total nonstructural carbohydrate concentration (TNC) were decreased, while leaf oxidative stress was increased. However, A, SLW, TNC, and measures of oxidative stress were no different than the control ca. 12 h after the heat waves ended, indicating rapid physiological recovery from the high-temperature stress. That end of season seed yield was reduced (~10%) only when heat waves were applied during early pod developmental stages indicates the yield loss had more to do with direct impacts of the heat waves on reproductive process than on photosynthesis. Soybean was unable to mitigate yield loss after heat waves given during late reproductive stages. This study shows that short high-temperature stress events that reduce photosynthesis and increase oxidative stress resulted in significant losses to soybean production in the Midwest, U.S. The study also suggests that to mitigate heat wave-induced yield loss, soybean needs improved reproductive and photosynthetic tolerance to high but increasingly common temperatures. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  17. Comprehensive Mutation Analysis of PMS2 in a Large Cohort of Probands Suspected of Lynch Syndrome or Constitutional Mismatch Repair Deficiency Syndrome.

    PubMed

    van der Klift, Heleen M; Mensenkamp, Arjen R; Drost, Mark; Bik, Elsa C; Vos, Yvonne J; Gille, Hans J J P; Redeker, Bert E J W; Tiersma, Yvonne; Zonneveld, José B M; García, Encarna Gómez; Letteboer, Tom G W; Olderode-Berends, Maran J W; van Hest, Liselotte P; van Os, Theo A; Verhoef, Senno; Wagner, Anja; van Asperen, Christi J; Ten Broeke, Sanne W; Hes, Frederik J; de Wind, Niels; Nielsen, Maartje; Devilee, Peter; Ligtenberg, Marjolijn J L; Wijnen, Juul T; Tops, Carli M J

    2016-11-01

    Monoallelic PMS2 germline mutations cause 5%-15% of Lynch syndrome, a midlife cancer predisposition, whereas biallelic PMS2 mutations cause approximately 60% of constitutional mismatch repair deficiency (CMMRD), a rare childhood cancer syndrome. Recently improved DNA- and RNA-based strategies are applied to overcome problematic PMS2 mutation analysis due to the presence of pseudogenes and frequent gene conversion events. Here, we determined PMS2 mutation detection yield and mutation spectrum in a nationwide cohort of 396 probands. Furthermore, we studied concordance between tumor IHC/MSI (immunohistochemistry/microsatellite instability) profile and mutation carrier state. Overall, we found 52 different pathogenic PMS2 variants explaining 121 Lynch syndrome and nine CMMRD patients. In vitro mismatch repair assays suggested pathogenicity for three missense variants. Ninety-one PMS2 mutation carriers (70%) showed isolated loss of PMS2 in their tumors, for 31 (24%) no or inconclusive IHC was available, and eight carriers (6%) showed discordant IHC (presence of PMS2 or loss of both MLH1 and PMS2). Ten cases with isolated PMS2 loss (10%; 10/97) harbored MLH1 mutations. We confirmed that recently improved mutation analysis provides a high yield of PMS2 mutations in patients with isolated loss of PMS2 expression. Application of universal tumor prescreening methods will however miss some PMS2 germline mutation carriers. © 2016 WILEY PERIODICALS, INC.

  18. Accounting for the economic risk caused by variation in disease severity in fungicide dose decisions, exemplified for Mycosphaerella graminicola on winter wheat.

    PubMed

    Te Beest, D E; Paveley, N D; Shaw, M W; van den Bosch, F

    2013-07-01

    A method is presented to calculate economic optimum fungicide doses accounting for the risk aversion of growers responding to variability in disease severity between crops. Simple dose-response and disease-yield loss functions are used to estimate net disease-related costs (fungicide cost plus disease-induced yield loss) as a function of dose and untreated severity. With fairly general assumptions about the shapes of the probability distribution of disease severity and the other functions involved, we show that a choice of fungicide dose which minimizes net costs, on average, across seasons results in occasional large net costs caused by inadequate control in high disease seasons. This may be unacceptable to a grower with limited capital. A risk-averse grower can choose to reduce the size and frequency of such losses by applying a higher dose as insurance. For example, a grower may decide to accept "high-loss" years 1 year in 10 or 1 year in 20 (i.e., specifying a proportion of years in which disease severity and net costs will be above a specified level). Our analysis shows that taking into account disease severity variation and risk aversion will usually increase the dose applied by an economically rational grower. The analysis is illustrated with data on Septoria tritici leaf blotch of wheat caused by Mycosphaerella graminicola. Observations from untreated field plots at sites across England over 3 years were used to estimate the probability distribution of disease severities at mid-grain filling. In the absence of a fully reliable disease forecasting scheme, reducing the frequency of high-loss years requires substantially higher doses to be applied to all crops. Disease-resistant cultivars reduce both the optimal dose at all levels of risk and the disease-related costs at all doses.

  19. Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

    NASA Astrophysics Data System (ADS)

    Hedges, John I.; Blanchette, Robert A.; Weliky, Karen; Devol, Allan H.

    1988-11-01

    Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. This fungus increased the absolute (weight loss-corrected) yield of the vanillic acid CuO reaction product above its initial level and exponentially decreased the absolute yields of all other lignin-derived phenols. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Although two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. Wood degraded by the three brown-rot fungi exhibited porous cell walls with greatly reduced integrity. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 (12 week samples), total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.

  20. Milk losses associated with somatic cell counts by parity and stage of lactation.

    PubMed

    Gonçalves, Juliano L; Cue, Roger I; Botaro, Bruno G; Horst, José A; Valloto, Altair A; Santos, Marcos V

    2018-05-01

    The reduction of milk production caused by subclinical mastitis in dairy cows was evaluated through the regression of test-day milk yield on log-transformed somatic cell counts (LnSCC). Official test-day records (n = 1,688,054) of Holstein cows (n = 87,695) were obtained from 719 herds from January 2010 to December 2015. Editing was performed to ensure both reliability and consistency for the statistical analysis, and the final data set comprised 232,937 test-day records from 31,692 Holstein cows in 243 herds. A segmented regression was fitted to estimate the cutoff point in the LnSCC scale where milk yield started to be affected by mastitis. The statistical model used to explain daily milk yield included the effect of herd as a random effect and days in milk and LnSCC as fixed effects regressions, and analyses were performed by parity and stage of lactation. The cutoff point where milk yield starts to be affected by changes in LnSCC was estimated to be around 2.52 (the average of all estimates of approximately 12,400 cells/mL) for Holsteins cows from Brazilian herds. For first-lactation cows, milk losses per unit increase of LnSCC had estimates around 0.68 kg/d in the beginning of the lactation [5 to 19 d in milk (DIM)], 0.55 kg/d in mid-lactation (110 to 124 DIM), and 0.97 kg/d at the end of the lactation (289 to 304 DIM). For second-lactation cows, milk losses per unit increase of LnSCC had estimates around 1.47 kg/d in the beginning of the lactation (5 to 19 DIM), 1.09 kg/d in mid-lactation (110 to 124 DIM), and 2.45 kg/d at the end of the lactation (289 to 304 DIM). For third-lactation cows, milk losses per unit increase of LnSCC had estimates around 2.22 kg/d in the beginning of the lactation (5 to 19 DIM), 1.13 kg/d in mid-lactation (140 to 154 DIM), and 2.65 kg/d at the end of the lactation (289 to 304 DIM). Daily milk losses caused by increased LnSCC were dependent on parity and stage of lactation, and these factors should be considered when estimating losses associated with subclinical mastitis. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. Plants under stress by parasitic plants.

    PubMed

    Hegenauer, Volker; Körner, Max; Albert, Markus

    2017-08-01

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

  2. Comparative virulence and molecular diversity of stripe rust (Puccinia striiformis f. sp. tritici) collections from Pakistan and United States

    USDA-ARS?s Scientific Manuscript database

    Information on virulence and molecular diversity of Puccinia striiformis f. sp. tritici (Pst) is a pre-requisite for mitigating the substantial yield losses caused by the stripe rust pathogen in Pakistan, the United States and other countries of the world. This study was undertaken to analyze both v...

  3. Resistance to Phakopsora pachyrhizi in soybean PI 587905 maps to the Rpp1 locus and exhibits variable dominance associated with plant ontogeny

    USDA-ARS?s Scientific Manuscript database

    Soybean rust, caused by Phakopsora pachyrhizi Sydow, results in significant yield loss worldwide. Soybean accession PI 587905, previously identified as having resistance to P. pachyrhizi, was used to create two independent populations (F2 plants and F2-derived F3 lines) segregating for resistance. ...

  4. The spatial genetic differentiation of the legume pod borer, Maruca vitrata F. (Lepidoptera: Pyralidae) populations in West Africa

    USDA-ARS?s Scientific Manuscript database

    The legume pod borer, Maruca vitrata, is an endemic insect pest that causes significant yield loss to the cowpea crop in West Africa, and contributes to food shortages and malnutrition in native human populations. The genetic structure of Maruca vitrata was investigated among five sites from Burkin...

  5. Swine manure application effects on ammonia volatilization, forage quality, and yield in the Pre-Amazon Region of Brazil

    USDA-ARS?s Scientific Manuscript database

    The use of swine manure as a nutrient source for pastures is increasingly common in Brazil, due to its low cost. However, this practice can cause nitrogen (N) losses in agricultural soil, where ammonia volatilization may be the main drawback, generating undesirable economic and environmental consequ...

  6. MIAG12: A Triticum timopheevii-derived powdery mildew resistance gene in common wheat on chromosome 7AL

    USDA-ARS?s Scientific Manuscript database

    Wheat powdery mildew is an economically important disease in cool and humid 2 environments. Powdery mildew causes yield losses as high as 48 percent through a reduction in 3 tiller survival, kernels per head and kernel size. Race-specific host resistance is the most 4 consistent, environmentally fri...

  7. The effect of the 'Hyuuga' soybean lesion type and canopy severity on yield loss in the presence of soybean rust (Phakopsora pachyrhizi)

    USDA-ARS?s Scientific Manuscript database

    Soybean rust, caused by the fungal pathogen Phakopsora pachyrhizi, occurs in many areas of the world and is a destructive foliar disease. Susceptible soybean leaves exhibit a “TAN” reaction characterized by lesions with abundant urediniospores, while resistant reactions involve either an immune resp...

  8. Re-engineering of the Pm21 transfer from Haynaldia villosa to bread wheat by induced homoeologous recombination

    USDA-ARS?s Scientific Manuscript database

    Blumeria graminis f. sp. tritici, the cause of powdery mildew, can generate serious grain yield losses in wheat. To expand the range of resistance genes freely available to wheat breeders, a Haynaldia villosa derived resistance gene Pm21 was transferred to chromosome 6AS of wheat by homoeologous rec...

  9. Discovery of a novel stem rust resistance allele in durum wheat that exhibits differential reactions to Ug99 isolates

    USDA-ARS?s Scientific Manuscript database

    Wheat stem rust, caused by Puccinia graminis f. sp. tritici Erikss. & E. Henn, can incur yield losses on susceptible cultivars of durum wheat, Triticum turgidum ssp. durum (Desf.) Husnot. Though several durum cultivars possess the stem rust resistance gene Sr13, additional genes in durum wheat effec...

  10. Data integration and knowledge management to facilitate research on plant-pathogen interactions: case study Solanum tuberosum – Verticillium

    USDA-ARS?s Scientific Manuscript database

    Verticillium wilt is an important disease causing considerable economic losses in potato production globally. Soil and environmental conditions affect symptom expression and the effect of the disease on yield. A ten year field trial has been conducted in order to better understand the dynamics of wi...

  11. Genetic analysis of rice blast disease resistance genes using USDA rice mini-core and a mapping population

    USDA-ARS?s Scientific Manuscript database

    Rice blast disease caused by the fungal pathogen Magnaporthe oryzae (M. oryzae) is one of the most destructive diseases of cultivated rice, resulting in significant yield loss each year all over the world. Developing and utilizing blast resistant rice varieties is the most economical and effective m...

  12. A soil-plate based pipeline for assessing cereal root growth in response to polyethylene glycol (PEG)-induced water deficit stress

    USDA-ARS?s Scientific Manuscript database

    Drought is a serious problem that causes losses in crop-yield every year, but the mechanisms underlying how roots respond to water deficit are difficult to study under controlled conditions. Methods for assaying root elongation and architecture, especially for seedlings, are commonly achieved on ar...

  13. Are seed and cone pathogens causing significant losses in Pacific Northwest seed orchards?

    Treesearch

    E.E. Nelson; W.G. Thies; C.Y. Li

    1986-01-01

    Cones systematically collected in 1983 from eight Douglas-fir seed orchards in western Washington and Oregon yielded large numbers of common molds. Fungi isolated from apparently healthy, developing cones were similar to those from necrotic cones. Necrosis in cones aborted in early stages of development was apparently not associated with pathogenic fungi or bacteria....

  14. ROI on yield data analysis systems through a business process management strategy

    NASA Astrophysics Data System (ADS)

    Rehani, Manu; Strader, Nathan; Hanson, Jeff

    2005-05-01

    The overriding motivation for yield engineering is profitability. This is achieved through application of yield management. The first application is to continually reduce waste in the form of yield loss. New products, new technologies and the dynamic state of the process and equipment keep introducing new ways to cause yield loss. In response, the yield management efforts have to continually come up with new solutions to minimize it. The second application of yield engineering is to aid in accurate product pricing. This is achieved through predicting future results of the yield engineering effort. The more accurate the yield prediction, the more accurate the wafer start volume, the more accurate the wafer pricing. Another aspect of yield prediction pertains to gauging the impact of a yield problem and predicting how long that will last. The ability to predict such impacts again feeds into wafer start calculations and wafer pricing. The question then is that if the stakes on yield management are so high why is it that most yield management efforts are run like science and engineering projects and less like manufacturing? In the eighties manufacturing put the theory of constraints1 into practice and put a premium on stability and predictability in manufacturing activities, why can't the same be done for yield management activities? This line of introspection led us to define and implement a business process to manage the yield engineering activities. We analyzed the best known methods (BKM) and deployed a workflow tool to make them the standard operating procedure (SOP) for yield managment. We present a case study in deploying a Business Process Management solution for Semiconductor Yield Engineering in a high-mix ASIC environment. We will present a description of the situation prior to deployment, a window into the development process and a valuation of the benefits.

  15. Atmospheric extinction in simulation tools for solar tower plants

    NASA Astrophysics Data System (ADS)

    Hanrieder, Natalie; Wilbert, Stefan; Schroedter-Homscheidt, Marion; Schnell, Franziska; Guevara, Diana Mancera; Buck, Reiner; Giuliano, Stefano; Pitz-Paal, Robert

    2017-06-01

    Atmospheric extinction causes significant radiation losses between the heliostat field and the receiver in a solar tower plants. These losses vary with site and time. State of the art is that in ray-tracing and plant optimization tools, atmospheric extinction is included by choosing between few constant standard atmospheric conditions. Even though some tools allow the consideration of site and time dependent extinction data, such data sets are nearly never available. This paper summarizes and compares the most common model equations implemented in several ray-tracing tools. There are already several methods developed and published to measure extinction on-site. An overview of the existing methods is also given here. Ray-tracing simulations of one exemplary tower plant at the Plataforma Solar de Almería (PSA) are presented to estimate the plant yield deviations between simulations using standard model equations instead of extinction time series. For PSA, the effect of atmospheric extinction accounts for losses between 1.6 and 7 %. This range is caused by considering overload dumping or not. Applying standard clear or hazy model equations instead of extinction time series lead to an underestimation of the annual plant yield at PSA. The discussion of the effect of extinction in tower plants has to include overload dumping. Situations in which overload dumping occurs are mostly connected to high radiation levels and low atmospheric extinction. Therefore it can be recommended that project developers should consider site and time dependent extinction data especially on hazy sites. A reduced uncertainty of the plant yield prediction can significantly reduce costs due to smaller risk margins for financing and EPCs. The generation of extinction data for several locations in form of representative yearly time series or geographical maps should be further elaborated.

  16. Relationship Between Crop Losses and Initial Population Densities of Meloidogyne arenaria in Winter-Grown Oriental Melon in Korea

    PubMed Central

    Kim, D.G.; Ferris, H.

    2002-01-01

    To determine the economic threshold level, oriental melon (Cucumis melo L. cv. Geumssaragi-euncheon) grafted on Shintozoa (Cucurbita maxima × Cu. moschata) was planted in plots (2 × 3 m) under a plastic film in February with a range of initial population densities (Pi) of Meloidogyne arenaria. The relationships of early, late, and total yield to Pi measured in September and January were adequately described by both linear regression and the Seinhorst damage model. Initial nematode densities in September in excess of 14 second-stage juveniles (J2)/100 cm³ soil caused losses in total yields that exceeded the economic threshold and indicate the need for fosthiazate nematicide treatment at current costs. Differences in yield-loss relationships to Pi between early- and late-season harvests enhance the resolution of the management decision and suggest approaches for optimizing returns. Determination of population levels for advisory purposes can be based on assay samples taken several months before planting, which allows time for implementation of management procedures. We introduce (i) an amendment of the economic threshold definition to reflect efficacy of the nematode management procedure under consideration, and (ii) the concept of profit limit as the nematode population at which net returns from the system will become negative. PMID:19265907

  17. 21st Century Heat Stress Projections and their Effects on US Livestock

    NASA Astrophysics Data System (ADS)

    McCabe, E.; Buzan, J. R.; Krishnan, S.; Huber, M.

    2016-12-01

    In this study we aim to determine future yield changes in the United States for livestock caused by heat stress, under the high greenhouse gas emissions scenario, representative concentration pathway 8.5 (RCP8.5). We use CMIP5 output and the Community Earth System Model Large Ensemble (CESM LENS), produced by the National Center for Atmospheric Research (NCAR). We apply the HumanIndexMod, a diagnostic heat stress package, to calculate Temperature Humidity Index for Comfort (THIC) and wet bulb temperature (Buzan et al., 2015). THIC is used to assess an animal's behavioral changes as it is subjected to discomfort. Using output from our simulations with the HumanIndexMod, we utilized the agricultural livestock model of St. Pierre et al. (2003). THIC and wet bulb temperatures are all projected by climate models to increase by the end of the century. We found that increases in THIC and heat stress are caused by both temperature and humidity increases. We show the differences for dry matter intake loss and milk loss for the Dairy Cow Model as well as other yield related variables. These variables are estimated to decrease overall production for dairy cattle, finishing hogs, poultry and various livestock. By the end of the 21st century (2071-2100), dairy cow milk production decreases by 14%, and food intake decreases by 11% compared to the beginning of the century (2005-2034). 35% less weight is gained and 19% less food is consumed by hogs the end of the century compared to the beginning of the century. We estimate and discuss resulting yield losses for the livestock industries and the implications of these losses in the United States. These results indicate that the effect of heat stress on livestock production will be highest for dairy cows, finishing hogs, and poultry.References:Buzan, J.R., K. Oleson, and M. Huber. 2015. Implementation and comparison of a suite of heat stress metrics within the Community Land Model version 4.5. Geoscien. Model Devel. 8(2): 151-170. St-Pierre, N.R., B. Cobanov, and G. Schnitkey. 2003. Economic losses from heat stress by US livestock industries. J. Dairy Sci. 86: E52-77.

  18. Interactions of viruses in Cowpea: effects on growth and yield parameters

    PubMed Central

    Kareem, KT; Taiwo, MA

    2007-01-01

    The study was carried out to investigate the effects of inoculating three cowpea cultivars: "OLO II", "OLOYIN" and IT86D-719 with three unrelated viruses: Cowpea aphid-borne mosaic virus (CABMV), genus Potyvirus, Cowpea mottle virus (CMeV), genus Carmovirus and Southern bean mosaic virus (SBMV), genus Sobemovirus singly and in mixture on growth and yield of cultivars at 10 and 30 days after planting (DAP). Generally, the growth and yield of the buffer inoculated control plants were significantly higher than those of the virus inoculated plants. Inoculation of plants at an early age of 10 DAP resulted in more severe effect than inoculations at a later stage of 30 DAP. The average values of plant height and number of leaves produced by plants inoculated 30 DAP were higher than those produced by plants inoculated 10 DAP. Most of the plants inoculated 10 DAP died and did not produce seeds. However, " OLOYIN" cultivar was most tolerant and produced reasonable yields when infected 30 DAP. The effect of single viruses on growth and yield of cultivars showed that CABMV caused more severe effects in IT86D-719, SBMV had the greatest effect on "OLO II" while CMeV induced the greatest effect on "OLOYIN". Yield was greatly reduced in double infections involving CABMV in combination with either CMeV or SBMV in "OLOYIN" and "OLO II", however, there was complete loss in yield of IT86D-719. Triple infection led to complete yield loss in all the three cultivars. PMID:17286870

  19. Assessing the mitigation potential of agricultural systems by optimization of the agricultural management: A modeling study on 8 agricultural observation sites across Europe with the process based model LandscapeDNDC

    NASA Astrophysics Data System (ADS)

    Molina Herrera, Saul; Haas, Edwin; Klatt, Steffen; Kraus, David; Kiese, Ralf; Butterbach-Bahl, Klaus

    2014-05-01

    The use of mineral nitrogen (N) fertilizers increase crop yields but cause the biggest anthropogenic source of nitrous oxide (N2O) emissions and strongly contribute to surface water eutrophication (e.g. nitrate leaching). The necessity to identify affordable strategies that improve crop production while improving ecosystem services are in continuous debate between policy decision makers and farmers. In this line, a lack commitment from farmers to enforce laws might result in the reduction of benefits. For this reason, farmers should aim to increase crop production and to reduce environmental harm by the adoption of precision climate smart agriculture tools applied to management practices for instance. In this study we present optimized strategies for 8 sites (agricultural and grassland ecosystems) with long term field observation across Europe to show the mitigation potential to reduce reactive nitrogen losses under the constrain of keeping yields at observed levels. LandscapeDNDC simulations of crop yields and associated nitrogen losses (N2O emissions and NO3 leaching) were evaluated against long term field measurements. The sites presented different management regimes including the main commodity crops (maize, wheat, barley, rape seeds, etc) and fertilization amendments (synthetic and organic fertilizers) in Europe. The simulations reproduced the observed yields, captured N2O emissions and NO3 leaching losses with high statistical presicion (r2), acurrency (ME) and agreement (RMSPEn). The mitigation potentials to reduce N losses while keeping yields at observed levels for all 8 sites were assesed by Monte Carlo optimizations of the individual underlying multi year agricultural management options (timings of planting and harvest, fertilization & manure applications and rates, residues management). In this study we present for all 8 agricultural observations sites their individual mitigation potentials to reduce N losses for multi year rotations. The conclusions for each side could result in management strategies to minimize environmental impact when such a model is used to predict best management practice on the site scale.

  20. Genotype-by-sequencing facilitates genetic mapping of a stem rust resistance locus in Aegilops umbellulata, a wild relative of cultivated wheat

    USDA-ARS?s Scientific Manuscript database

    Background: Wild relatives of wheat play a significant role in wheat improvement as a source of genetic diversity. Stem rust disease of wheat causes significant yield losses at the global level and stem rust pathogen race TTKSK (Ug99) is virulent to most previously deployed resistance genes. Therefo...

  1. Influence of a non-copper algicide on the cyanobacterium, Nostoc spongiaeforme, and the green alga, Hydrodictyon reticulatum, in field and laboratory experiments

    USDA-ARS?s Scientific Manuscript database

    Cyanobacteria grow in California rice fields where they form large mats that may smoother seedlings or cause them to dislodge, resulting in yield loss. The most troublesome species is Nostoc spongiaeforme. It is very difficult to control using currently accepted methods, i.e., aerial applications of...

  2. The impact of genotyping-by-sequencing pipelines on SNP discovery and identification of markers associated verticillium wilt resistance in autotetraploid alfalfa (sedicago sativa l.)

    USDA-ARS?s Scientific Manuscript database

    Verticillium wilt (VW) of alfalfa is a soilborne disease that causes severe yield loss in alfalfa. To identify molecular markers associated with VW resistance, an integrated framework of genome-wide association study (GWAS) with high-throughput genotyping by sequencing (GBS) was used for mapping lo...

  3. Ovipositional preference and larval performance of the banded sunflower moth (Lepidoptera: Tortricidae) and its larval parasitoids on resistant and susceptible lines of sunflower (Asterales: Asteraceae)

    USDA-ARS?s Scientific Manuscript database

    Banded sunflower moth, Cochylis hospes Walsingham, is one of the most destructive seed-feeding insect pests of sunflowers, causing significant economic yield losses in the northern Great Plains. In an attempt to understand host-plant resistance mechanisms for this pest, we field tested over several ...

  4. Identification of soybean proteins and genes differentially regulated in near isogenic lines differing in resistance to aphid infestation

    USDA-ARS?s Scientific Manuscript database

    The soybean aphid, a plant sap sucking insect, is an important soybean pest in the USA causing significant yield losses. The Rag2 gene of soybean provides resistance to soybean aphid biotypes 1 and 2. Transcriptomic and proteomic analyses were performed on near isogenic lines (NILs) with the Rag2 al...

  5. Preliminary evaluation of resistance to powdery mildew (Podosphaera xanthii) in AVRDC collections of bitter gourd (Momordica charantia L.)

    USDA-ARS?s Scientific Manuscript database

    Bitter gourd (Momordica charantia L.) is an important market vegetable in Asia, where it is also used in folk medicine to manage type 2 diabetes. Powdery mildew caused by Podosphaera xanthii is a serious fungal disease of bitter gourd and yield losses of up to 50% have been reported. After observi...

  6. Formulations of the endophytic bacterium Bacillus subtilis Tu-100 suppress Sclerotinia sclerotiorum on oilseed rape and improve plant vigor in field trials conducted at separate locations

    USDA-ARS?s Scientific Manuscript database

    Sclerotinia sclerotiorum causes serious yield losses in crops in The People’s Republic of China. Two formulations of oilseed rape seed containing the endophytic bacterium Bacillus subtilis Tu-100 were evaluated for suppression of this pathogen in field trials conducted at two independent locations....

  7. Reaction of maturity group V soybean plant introductions to Phomopsis Seed Decay in Arkansas Mississippi and Missouri 2009

    USDA-ARS?s Scientific Manuscript database

    In 2009, Soybean Phomopsis seed decay (PSD) caused over 12 million bushels of yield loss in 16 southern states. This disease severely affects soybean seed quality due to the reduction of seed viability, oil content, and alteration of seed composition, and it may also increase moldy and/or split seed...

  8. Effectiveness of kaolin clay particle film in managing Helopeltis collaris (Hemiptera: Miridae), a major pest of cacao in the Philippines

    USDA-ARS?s Scientific Manuscript database

    Helopeltis collaris Stal, commonly known as cacao mirid or capsid bug is one of the major pests of cacao in Southeast Asia. Recent survey of cacao pests in the Philippines showed that cacao mirid bug is causing significant yield loss particularly in cacao growing areas in Luzon. Kaolin is a naturall...

  9. Evaluation of spring wheat cultivars to fungicide application for control of stripe rust in 2016

    USDA-ARS?s Scientific Manuscript database

    To evaluate spring wheat cultivars grown in the U.S. Pacific Northwest to fungicide application for control of stripe rust and assess their yield loss caused by the disease, this study was conducted in a field near Pullman, WA. Spring wheat genotype ‘Avocet S’ (AvS) was used as a susceptible check, ...

  10. Whole-Genome Characterization of Prunus necrotic ringspot virus Infecting Sweet Cherry in China

    PubMed Central

    2018-01-01

    ABSTRACT Prunus necrotic ringspot virus (PNRSV) causes yield loss in most cultivated stone fruits, including sweet cherry. Using a small RNA deep-sequencing approach combined with end-genome sequence cloning, we identified the complete genomes of all three PNRSV strands from PNRSV-infected sweet cherry trees and compared them with those of two previously reported isolates. PMID:29496825

  11. Water management challenges at Mushandike irrigation scheme in Runde catchment, Zimbabwe

    NASA Astrophysics Data System (ADS)

    Malanco, Jose A.; Makurira, Hodson; Kaseke, Evans; Gumindoga, Webster

    2018-05-01

    Mushandike Irrigation Scheme, constructed in 1939, is located in Masvingo District and is one of the oldest irrigation schemes in Zimbabwe. Since 2002, the scheme has experienced severe water shortages resulting in poor crop yields. The low crop yields have led to loss of income to the smallholder farmers who constitute the irrigation scheme leading to water conflicts. The water stress at the scheme has been largely attributed to climate change and the uncontrolled expansion of the land under irrigation which is currently about 1000 ha against a design area of 613 ha. This study sought to determine the actual causes of water shortage at Mushandike Irrigation Scheme. Hydro-climatic data was analysed to establish if the Mushandike River system generates enough water to guarantee the calculated annual yield of the dam. Irrigation demands and efficiencies were compared against water availability and dam releases to establish if there is any deficit. The Spearman's Rank Correlation results of 0.196 for rainfall and 0.48 for evaporation confirmed positive but insignificant long-term changes in hydro-climatic conditions in the catchment. Water budgets established that the yield of the dam of 9.2 × 106 m3 year-1 is sufficient to support the expanded area of 1000 ha provided in-field water management efficiencies are adopted. The study concludes that water shortages currently experienced at the scheme are a result of inefficient water management (e.g. over-abstraction from the dam beyond the firm yield, adoption of inefficient irrigation methods and high channel losses in the canal system) and are not related to hydro-climatic conditions. The study also sees no value in considering inter-basin water transfer to cushion the losses being experienced at the scheme.

  12. Alumina Handling Dustiness

    NASA Astrophysics Data System (ADS)

    Authier-Martin, Monique

    Dustiness of calcined alumina is a major concern, causing undesirable working conditions and serious alumina losses. These losses occur primarily during unloading and handling or pot loading and crust breaking. The handling side of the problem is first addressed. The Perra pulvimeter constitutes a simple and reproducible tool to quantify handling dustiness and yields results in agreement with plant experience. Attempts are made to correlate dustiness with bulk properties (particle size, attrition index, …) for a large number of diverse aluminas. The characterization of the dust generated with the Perra pulvimeter is most revealing. The effect of the addition of E.S.P. dust is also reported.

  13. Aircraft Loss of Control Causal Factors and Mitigation Challenges

    NASA Technical Reports Server (NTRS)

    Jacobson, Steven R.

    2010-01-01

    Loss of control is the leading cause of jet fatalities worldwide. Aside from their frequency of occurrence, accidents resulting from loss of aircraft control seize the public s attention by yielding a large number of fatalities in a single event. In response to the rising threat to aviation safety, the NASA Aviation Safety Program has conducted a study of the loss of control problem. This study gathered four types of information pertaining to loss of control accidents: (1) statistical data; (2) individual accident reports that cite loss of control as a contributing factor; (3) previous meta-analyses of loss of control accidents; and (4) inputs solicited from aircraft manufacturers, air carriers, researchers, and other industry stakeholders. Using these information resources, the study team identified the causal factors that were cited in the greatest number of loss of control accidents, and which were emphasized most by industry stakeholders. This report describes the study approach, the key causal factors for aircraft loss of control, and recommended mitigation strategies to make near-term impacts, mid-term impacts, and Next Generation Air Transportation System impacts on the loss of control accident statistics

  14. Enhanced Ethanol Production from De-Ashed Paper Sludge by Simultaneous Saccharification and Fermentation and Simultaneous Saccharification and Co-Fermentation

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

    Kang, L.; Wang, W.; Pallapolu, V. R.

    2011-11-01

    A previous study demonstrated that paper sludges with high ash contents can be converted to ethanol by simultaneous saccharification and fermentation (SSF) or simultaneous saccharification and co-fermentation (SSCF). High ash content in the sludge, however, limited solid loading in the bioreactor, causing low product concentration. To overcome this problem, sludges were de-ashed before SSF and SSCF. Low ash content in sludges also increased the ethanol yield to the extent that the enzyme dosage required to achieve 70% yield in the fermentation process was reduced by 30%. High solid loading in SSF and SSCF decreased the ethanol yield. High agitation andmore » de-ashing of the sludges were able to restore the part of the yield loss caused by high solid loading. Substitution of the laboratory fermentation medium (peptone and yeast extract) with corn steep liquor did not bring about any adverse effects in the fermentation. Fed-batch operation of the SSCF and SSF using low-ash content sludges was effective in raising the ethanol concentration, achieving 47.8 g/L and 60.0 g/L, respectively.« less

  15. Aircraft Loss of Control Study

    NASA Technical Reports Server (NTRS)

    Jacobson, Steven R.

    2010-01-01

    Loss of control has become the leading cause of jet fatalities worldwide. Aside from their frequency of occurrence, accidents resulting from loss of aircraft control seize the public s attention by yielding large numbers of fatalities in a single event. In response to the rising threat to aviation safety, NASA's Aviation Safety Program has conducted a study of the loss of control problem. This study gathered four types of information pertaining to loss of control accidents: (1) statistical data; (2) individual accident reports that cite loss of control as a contributing factor; (3) previous meta-analyses of loss of control accidents; and (4) inputs solicited from aircraft manufacturers, air carriers, researchers, and other industry stakeholders. Using these information resources, the study team identified causal factors that were cited in the greatest number of loss of control accidents, and which were emphasized most by industry stakeholders. For each causal factor that was linked to loss of control, the team solicited ideas about what solutions are required and future research efforts that could potentially help avoid their occurrence or mitigate their consequences when they occurred in flight.

  16. A methodology for overall consequence modeling in chemical industry.

    PubMed

    Arunraj, N S; Maiti, J

    2009-09-30

    Risk assessment in chemical process industry is a very important issue for safeguarding human and the ecosystem from damages caused to them. Consequence assessment is an integral part of risk assessment. However, the commonly used consequence estimation methods involve time-consuming complex mathematical models and simple assimilation of losses without considering all the consequence factors. This lead to the deterioration of quality of estimated risk value. So, the consequence modeling has to be performed in detail considering all major losses with optimal time to improve the decisive value of risk. The losses can be broadly categorized into production loss, assets loss, human health and safety loss, and environment loss. In this paper, a conceptual framework is developed to assess the overall consequence considering all the important components of major losses. Secondly, a methodology is developed for the calculation of all the major losses, which are normalized to yield the overall consequence. Finally, as an illustration, the proposed methodology is applied to a case study plant involving benzene extraction. The case study result using the proposed consequence assessment scheme is compared with that from the existing methodologies.

  17. Control of plant virus diseases in cool-season grain legume crops.

    PubMed

    Makkouk, Khaled M; Kumari, Safaa G; van Leur, Joop A G; Jones, Roger A C

    2014-01-01

    Cool-season grain legume crops become infected with a wide range of viruses, many of which cause serious diseases and major yield losses. This review starts by discussing which viruses are important in the principal cool-season grain legume crops in different parts of the world, the losses they cause and their economic impacts in relation to control. It then describes the main types of control measures available: host resistance, phytosanitary measures, cultural measures, chemical control, and biological control. Examples are provided of successful deployment of the different types of measures to control virus epidemics in cool-season grain legume crops. Next it emphasizes the need for integrated approaches to control because single control measures used alone rarely suffice to adequately reduce virus-induced yield losses in these crops. Development of effective integrated disease management (IDM) strategies depends on an interdisciplinary team approach to (i) understand the ecological and climatic factors which lead to damaging virus epidemics and (ii) evaluate the effectiveness of individual control measures. In addition to using virus-resistant cultivars, other IDM components include sowing virus-tested seed stocks, selecting cultivars with low seed transmission rates, using diverse phytosanitary or cultural practices that minimize the virus source or reduce its spread, and using selective pesticides in an environmentally responsible way. The review finishes by briefly discussing the implications of climate change in increasing problems associated with control and the opportunities to control virus diseases more effectively through new technologies.

  18. A genome-wide association study of resistance to stripe rust (Puccinia striiformis f. sp. tritici) in a worldwide collection of hexaploid spring wheat (Triticum aestivum L.)

    USDA-ARS?s Scientific Manuscript database

    New races of Puccinia striiformis f. sp. tritici (Pst), the causal pathogen of wheat stripe rust, show high virulence to previously deployed resistance genes and are causing large yield losses worldwide. To identify new sources of resistance we performed a genome-wide association study (GWAS) using...

  19. Phenotypic and genotypic characterization of race TKTTF of Puccinia graminis f. sp. tritici that caused a wheat stem rust epidemic in southern Ethiopia in 2013-2014

    USDA-ARS?s Scientific Manuscript database

    A severe stem rust epidemic occurred in southern Ethiopia during November 2013 to January 2014 with yield losses close to 100% on the most widely grown wheat cultivar, 'Digalu'. Sixty-four stem rust samples collected from the regions were analyzed. A meteorological model for airborne spore dispersal...

  20. Dn10, a new gene conferring resistance to Russian wheat aphid biotype 2 in Iranian wheat landrace PI 682675

    USDA-ARS?s Scientific Manuscript database

    Russian wheat aphid (RWA) is a serious pest of wheat and barley that causes heavy yield losses in many countries, and RWA biotype 2 (RWA2) is virulent to most RWA resistance genes. The objective of this study was to characterize a gene for resistance to RWA2 in Iranian landrace PI 682675, a single ...

  1. Coupling Spore Traps and Quantitative PCR Assays for Detection of Cercospora sojina, the Causal Agent of Soybean Frogeye Leaf Spot

    USDA-ARS?s Scientific Manuscript database

    Frogeye leaf spot (FLS), caused by Cercospora sojina Hara, is a common disease of soybean. Significant yield losses (10–60%) have been attributed to FLS. We present a novel trapping approach using Vaseline coated slides placed at a 45° angle within a passive, wind-vane spore trap used in combination...

  2. Resistance mechanisms to toxin-mediated charcoal rot infection in maturity group III soybean: role of seed phenol lignin soflavones sugars and seed minerals in charcoal rot resistance

    USDA-ARS?s Scientific Manuscript database

    Charcoal rot is a disease caused by the fungus Macrophomina phaseolina (Tassi) Goid, and thought to infect the plants through roots by a toxin-mediated mechanism, resulting in yield loss and poor seed quality, especially under drought conditions. The mechanism by which this infection occurs is not y...

  3. Sampling techniques and detection methods for developing risk assessments for root-knot nematode (Meloidogyne incognita) on lima bean (Phaseolus lunatus) in the Mid-Atlantic region

    USDA-ARS?s Scientific Manuscript database

    Lima bean, Phaseolus lunatus, is a cornerstone crop in the Mid-Atlantic region and Meloidogyne incognita, the southern root knot nematode (RKN), causes significant yield loss. The RKN has become more pervasive as toxic nematicides have been removed from the market, and risk evaluation research is ne...

  4. Heat waves imposed during early pod development in soybean (Glycine max) cause significant yield loss despite a rapid recovery from oxidative stress

    USDA-ARS?s Scientific Manuscript database

    This study is the first field based experiment that uses IR heaters to study the effects of a regionally defined heat wave on soybean physiology and productivity. The heating technology was successful and all of the heat waves were maintained at the target temperature for the three day duration of t...

  5. Whole-Genome Characterization of Prunus necrotic ringspot virus Infecting Sweet Cherry in China.

    PubMed

    Wang, Jiawei; Zhai, Ying; Zhu, Dongzi; Liu, Weizhen; Pappu, Hanu R; Liu, Qingzhong

    2018-03-01

    Prunus necrotic ringspot virus (PNRSV) causes yield loss in most cultivated stone fruits, including sweet cherry. Using a small RNA deep-sequencing approach combined with end-genome sequence cloning, we identified the complete genomes of all three PNRSV strands from PNRSV-infected sweet cherry trees and compared them with those of two previously reported isolates. Copyright © 2018 Wang et al.

  6. Maximization of DRAM yield by control of surface charge and particle addition during high dose implantation

    NASA Astrophysics Data System (ADS)

    Horvath, J.; Moffatt, S.

    1991-04-01

    Ion implantation processing exposes semiconductor devices to an energetic ion beam in order to deposit dopant ions in shallow layers. In addition to this primary process, foreign materials are deposited as particles and surface films. The deposition of particles is a major cause of IC yield loss and becomes even more significant as device dimensions are decreased. Control of particle addition in a high-volume production environment requires procedures to limit beamline and endstation sources, control of particle transport, cleaning procedures and a well grounded preventative maintenance philosophy. Control of surface charge by optimization of the ion beam and electron shower conditions and measurement with a real-time charge sensor has been effective in improving the yield of NMOS and CMOS DRAMs. Control of surface voltages to a range between 0 and -20 V was correlated with good implant yield with PI9200 implanters for p + and n + source-drain implants.

  7. Genetic variations in ARE1 mediate grain yield by modulating nitrogen utilization in rice.

    PubMed

    Wang, Qing; Nian, Jinqiang; Xie, Xianzhi; Yu, Hong; Zhang, Jian; Bai, Jiaoteng; Dong, Guojun; Hu, Jiang; Bai, Bo; Chen, Lichao; Xie, Qingjun; Feng, Jian; Yang, Xiaolu; Peng, Juli; Chen, Fan; Qian, Qian; Li, Jiayang; Zuo, Jianru

    2018-02-21

    In crops, nitrogen directly determines productivity and biomass. However, the improvement of nitrogen utilization efficiency (NUE) is still a major challenge in modern agriculture. Here, we report the characterization of are1, a genetic suppressor of a rice fd-gogat mutant defective in nitrogen assimilation. ARE1 is a highly conserved gene, encoding a chloroplast-localized protein. Loss-of-function mutations in ARE1 cause delayed senescence and result in 10-20% grain yield increases, hence enhance NUE under nitrogen-limiting conditions. Analysis of a panel of 2155 rice varieties reveals that 18% indica and 48% aus accessions carry small insertions in the ARE1 promoter, which result in a reduction in ARE1 expression and an increase in grain yield under nitrogen-limiting conditions. We propose that ARE1 is a key mediator of NUE and represents a promising target for breeding high-yield cultivars under nitrogen-limiting condition.

  8. Soil Water Availability Modulation Over Estimated Relative Yield Losses in Wheat (Triticum aestivum L.) Due to Ozone Exposure

    PubMed Central

    De la Torre, Daniel; Sierra, Maria Jose

    2007-01-01

    The approach developed by Fuhrer in 1995 to estimate wheat yield losses induced by ozone and modulated by the soil water content (SWC) was applied to the data on Catalonian wheat yields. The aim of our work was to apply this approach and adjust it to Mediterranean environmental conditions by means of the necessary corrections. The main objective pursued was to prove the importance of soil water availability in the estimation of relative wheat yield losses as a factor that modifies the effects of tropospheric ozone on wheat, and to develop the algorithms required for the estimation of relative yield losses, adapted to the Mediterranean environmental conditions. The results show that this is an easy way to estimate relative yield losses just using meteorological data, without using ozone fluxes, which are much more difficult to calculate. Soil water availability is very important as a modulating factor of the effects of ozone on wheat; when soil water availability decreases, almost twice the amount of accumulated exposure to ozone is required to induce the same percentage of yield loss as in years when soil water availability is high. PMID:17619747

  9. North-south differences in Chinese agricultural losses due to climate-change-influenced droughts

    NASA Astrophysics Data System (ADS)

    Qiang, Zhang; Lanying, Han; Jingjing, Lin; Qingyan, Cheng

    2018-01-01

    One of the effects of global climate change is increase in the frequency and severity of drought, which strongly affects the Chinese agricultural production. In order to cope these changes more effectively, it is important to document and analyze the agricultural losses caused by drought. We collected and analyzed conventional meteorological data and agricultural statistics data, in order to outline trends in drought occurrence and decline in agricultural yield. Data were assembled for the period 1960-2010. The study pays particular attention to regional differences between northern and southern China. Our results show the drought-caused agricultural loss rates (DCALR) in China have increased by approximately 0.5% per decade in the past 50 years. The study area in this paper is for the whole of the People's Republic of China, minus the Qinghai-Tibetan Plateau; when we analyzed regional differences, we found that losses increased by approximately 0.6% per decade in northern China, close to twice the increase in southern China. Moreover, drought risks and agricultural losses are rising faster in northern China. Our results also indicate that the agriculture in northern China is more sensitive to changes in precipitation, whereas the agriculture in southern China is more sensitive to temperature changes.

  10. Conserved Genes Act as Modifiers of Invertebrate SMN Loss of Function Defects

    PubMed Central

    Chang, Howard C.; Sen, Anindya; Kalloo, Geetika; Harris, Jevede; Barsby, Tom; Walsh, Melissa B.; Satterlee, John S.; Li, Chris; Van Vactor, David; Artavanis-Tsakonas, Spyros; Hart, Anne C.

    2010-01-01

    Spinal Muscular Atrophy (SMA) is caused by diminished function of the Survival of Motor Neuron (SMN) protein, but the molecular pathways critical for SMA pathology remain elusive. We have used genetic approaches in invertebrate models to identify conserved SMN loss of function modifier genes. Drosophila melanogaster and Caenorhabditis elegans each have a single gene encoding a protein orthologous to human SMN; diminished function of these invertebrate genes causes lethality and neuromuscular defects. To find genes that modulate SMN function defects across species, two approaches were used. First, a genome-wide RNAi screen for C. elegans SMN modifier genes was undertaken, yielding four genes. Second, we tested the conservation of modifier gene function across species; genes identified in one invertebrate model were tested for function in the other invertebrate model. Drosophila orthologs of two genes, which were identified originally in C. elegans, modified Drosophila SMN loss of function defects. C. elegans orthologs of twelve genes, which were originally identified in a previous Drosophila screen, modified C. elegans SMN loss of function defects. Bioinformatic analysis of the conserved, cross-species, modifier genes suggests that conserved cellular pathways, specifically endocytosis and mRNA regulation, act as critical genetic modifiers of SMN loss of function defects across species. PMID:21124729

  11. Niclosamide inhibits leaf blight caused by Xanthomonas oryzae in rice

    PubMed Central

    Kim, Sung-Il; Song, Jong Tae; Jeong, Jin-Yong; Seo, Hak Soo

    2016-01-01

    Rice leaf blight, which is caused by the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), results in huge losses in grain yield. Here, we show that Xoo-induced rice leaf blight is effectively controlled by niclosamide, an oral antihelminthic drug and molluscicide, which also functions as an anti-tumor agent. Niclosamide directly inhibited the growth of the three Xoo strains PXO99, 10208 and K3a. Niclosamide moved long distances from the site of local application to distant rice tissues. Niclosamide also increased the levels of salicylate and induced the expression of defense-related genes such as OsPR1 and OsWRKY45, which suppressed Xoo-induced leaf wilting. Niclosamide had no detrimental effects on vegetative/reproductive growth and yield. These combined results indicate that niclosamide can be used to block bacterial leaf blight in rice with no negative side effects. PMID:26879887

  12. Phenalenone-type phytoalexins mediate resistance of banana plants (Musa spp.) to the burrowing nematode Radopholus similis.

    PubMed

    Hölscher, Dirk; Dhakshinamoorthy, Suganthagunthalam; Alexandrov, Theodore; Becker, Michael; Bretschneider, Tom; Buerkert, Andreas; Crecelius, Anna C; De Waele, Dirk; Elsen, Annemie; Heckel, David G; Heklau, Heike; Hertweck, Christian; Kai, Marco; Knop, Katrin; Krafft, Christoph; Maddula, Ravi K; Matthäus, Christian; Popp, Jürgen; Schneider, Bernd; Schubert, Ulrich S; Sikora, Richard A; Svatoš, Aleš; Swennen, Rony L

    2014-01-07

    The global yield of bananas-one of the most important food crops-is severely hampered by parasites, such as nematodes, which cause yield losses up to 75%. Plant-nematode interactions of two banana cultivars differing in susceptibility to Radopholus similis were investigated by combining the conventional and spatially resolved analytical techniques (1)H NMR spectroscopy, matrix-free UV-laser desorption/ionization mass spectrometric imaging, and Raman microspectroscopy. This innovative combination of analytical techniques was applied to isolate, identify, and locate the banana-specific type of phytoalexins, phenylphenalenones, in the R. similis-caused lesions of the plants. The striking antinematode activity of the phenylphenalenone anigorufone, its ingestion by the nematode, and its subsequent localization in lipid droplets within the nematode is reported. The importance of varying local concentrations of these specialized metabolites in infected plant tissues, their involvement in the plant's defense system, and derived strategies for improving banana resistance are highlighted.

  13. Frost trends and their estimated impact on yield in the Australian wheatbelt

    PubMed Central

    Zheng, Bangyou; Chapman, Scott C.; Christopher, Jack T.; Frederiks, Troy M.; Chenu, Karine

    2015-01-01

    Radiant spring frosts occurring during reproductive developmental stages can result in catastrophic yield loss for wheat producers. To better understand the spatial and temporal variability of frost, the occurrence and impact of frost events on rain-fed wheat production was estimated across the Australian wheatbelt for 1957–2013 using a 0.05 ° gridded weather data set. Simulated yield outcomes at 60 key locations were compared with those for virtual genotypes with different levels of frost tolerance. Over the last six decades, more frost events, later last frost day, and a significant increase in frost impact on yield were found in certain regions of the Australian wheatbelt, in particular in the South-East and West. Increasing trends in frost-related yield losses were simulated in regions where no significant trend of frost occurrence was observed, due to higher mean temperatures accelerating crop development and causing sensitive post-heading stages to occur earlier, during the frost risk period. Simulations indicated that with frost-tolerant lines the mean national yield could be improved by up to 20% through (i) reduced frost damage (~10% improvement) and (ii) the ability to use earlier sowing dates (adding a further 10% improvement). In the simulations, genotypes with an improved frost tolerance to temperatures 1 °C lower than the current 0 °C reference provided substantial benefit in most cropping regions, while greater tolerance (to 3 °C lower temperatures) brought further benefits in the East. The results indicate that breeding for improved reproductive frost tolerance should remain a priority for the Australian wheat industry, despite warming climates. PMID:25922479

  14. Dynamic evolution of resistance gene analogs in the orthologous genomic regions of powdery mildew resistance gene MlIW170 in Triticum dicoccoides and Aegilops tauschii

    USDA-ARS?s Scientific Manuscript database

    Wheat is one of the most important staple grain crops in the world. Powdery mildew disease caused by Blumeria graminis f.sp. tritici can result in significant losses in both grain yield and quality in wheat. In this study, the wheat powdery mildew resistance gene MlIW170 locus located on the short ...

  15. Discovery of a new genotype of Squash mosaic virus through deep sequencing of small RNAs and development of a qRT-PCR for broad spectrum detection

    USDA-ARS?s Scientific Manuscript database

    Squash mosaic virus (SqMV), a seed-borne virus belonging to the genus Commovirus in the family Comoviridae, could cause a serious yield loss on cucurbit crops worldwide. SqMV has a bipartite single-stranded ribonucleic acid (RNA) genome (RNA-1 and RNA-2) encapsidated separately with two capsid prote...

  16. Anomalous effects in the aluminum oxide sputtering yield

    NASA Astrophysics Data System (ADS)

    Schelfhout, R.; Strijckmans, K.; Depla, D.

    2018-04-01

    The sputtering yield of aluminum oxide during reactive magnetron sputtering has been quantified by a new and fast method. The method is based on the meticulous determination of the reactive gas consumption during reactive DC magnetron sputtering and has been deployed to determine the sputtering yield of aluminum oxide. The accuracy of the proposed method is demonstrated by comparing its results to the common weight loss method excluding secondary effects such as redeposition. Both methods exhibit a decrease in sputtering yield with increasing discharge current. This feature of the aluminum oxide sputtering yield is described for the first time. It resembles the discrepancy between published high sputtering yield values determined by low current ion beams and the low deposition rate in the poisoned mode during reactive magnetron sputtering. Moreover, the usefulness of the new method arises from its time-resolved capabilities. The evolution of the alumina sputtering yield can now be measured up to a resolution of seconds. This reveals the complex dynamical behavior of the sputtering yield. A plausible explanation of the observed anomalies seems to originate from the balance between retention and out-diffusion of implanted gas atoms, while other possible causes are commented.

  17. Impacts of biofuel cultivation on mortality and crop yields

    NASA Astrophysics Data System (ADS)

    Ashworth, K.; Wild, O.; Hewitt, C. N.

    2013-05-01

    Ground-level ozone is a priority air pollutant, causing ~ 22,000 excess deaths per year in Europe, significant reductions in crop yields and loss of biodiversity. It is produced in the troposphere through photochemical reactions involving oxides of nitrogen (NOx) and volatile organic compounds (VOCs). The biosphere is the main source of VOCs, with an estimated 1,150TgCyr-1 (~ 90% of total VOC emissions) released from vegetation globally. Isoprene (2-methyl-1,3-butadiene) is the most significant biogenic VOC in terms of mass (around 500TgCyr-1) and chemical reactivity and plays an important role in the mediation of ground-level ozone concentrations. Concerns about climate change and energy security are driving an aggressive expansion of bioenergy crop production and many of these plant species emit more isoprene than the traditional crops they are replacing. Here we quantify the increases in isoprene emission rates caused by cultivation of 72Mha of biofuel crops in Europe. We then estimate the resultant changes in ground-level ozone concentrations and the impacts on human mortality and crop yields that these could cause. Our study highlights the need to consider more than simple carbon budgets when considering the cultivation of biofuel feedstock crops for greenhouse-gas mitigation.

  18. The impact exploration of agricultural drought on winter wheat yield in the North China Plain

    NASA Astrophysics Data System (ADS)

    Yang, Jianhua; Wu, Jianjun; Han, Xinyi; Zhou, Hongkui

    2017-04-01

    Drought is one of the most serious agro-climatic disasters in the North China Plain, which has a great influence on winter wheat yield. Global warming exacerbates the drought trend of this region, so it is important to study the effect of drought on winter wheat yield. In order to assess the drought-induced winter wheat yield losses, SPEI (standardized precipitation evapotranspiration index), the widely used drought index, was selected to quantify the drought from 1981 to 2013. Additionally, the EPIC (Environmental Policy Integrated Climate) crop model was used to simulate winter wheat yield at 47 stations in this region from 1981 to 2013. We analyzed the relationship between winter wheat yield and the SPEI at different time scales in each month during the growing season. The trends of the SPEI and the trends of winter wheat yield at 47 stations over the past 32 years were compared with each other. To further quantify the effect of drought on winter wheat yield, we defined the year that SPEI varied from -0.5 to 0.5 as the normal year, and calculated the average winter wheat yield of the normal years as a reference yield, then calculated the reduction ratios of winter wheat based on the yields mentioned above in severe drought years. As a reference, we compared the results with the reduction ratios calculated from the statistical yield data. The results showed that the 9 to 12-month scales' SPEI in April, May and June had a high correlation with winter wheat yield. The trends of the SPEI and the trends of winter wheat yield over the past 32 years showed a positive correlation (p<0.01) and have similar spatial distributions. The proportion of the stations with the same change trend between the SPEI and winter wheat yield was 70%, indicating that drought was the main factor leading to a decline in winter wheat yield in this region. The reduction ratios based on the simulated yield and the reduction ratios calculated from the statistical yield data have a high positive correlation (p<0.01), which may provide a way to quantitatively evaluate the winter wheat yield losses caused by drought. Key words: drought, winter wheat yield, SPEI, EPIC, the North China Plain

  19. Mature oil palm plantations are thirstier than tropical forests

    NASA Astrophysics Data System (ADS)

    Manoli, G.; Meijide, A.; Huth, N.; Knohl, A.; Kosugi, Y.; Burlando, P.; Ghazoul, J.; Fatichi, S.

    2017-12-01

    Oil Palm (OP) is the highest yielding cash-crop in the world but, being the driver of significant tropical forest losses, it is also considered the "world's most hated crop". Despite substantial research on the impact of OP on ecosystem degradation, biodiversity losses, and carbon emissions, little is known on the ecohydrological impacts of forest conversion to OP. Here we employ numerical simulations constrained by field observations to quantify changes in ecosystem evapotranspiration (ET), infiltration/runoff, gross primary productivity (GPP) and surface temperature (Ts) due to OP establishment. Compared to pristine forests, young OP plantations decrease ET, causing an increase in Ts, but the changes become less pronounced as plantations grow. Mature plantations have a very high GPP to sustain the oil palm yield and, given relatively similar water use efficiency, they transpire more water that the forests they have replaced. Hence, the high fruit productivity of OP comes at the expense of water consumption. Our mechanistic modeling results corroborate anecdotal evidence of water scarcity issues in OP-dominated landscapes.

  20. From GCM grid cell to agricultural plot: scale issues affecting modelling of climate impact

    PubMed Central

    Baron, Christian; Sultan, Benjamin; Balme, Maud; Sarr, Benoit; Traore, Seydou; Lebel, Thierry; Janicot, Serge; Dingkuhn, Michael

    2005-01-01

    General circulation models (GCM) are increasingly capable of making relevant predictions of seasonal and long-term climate variability, thus improving prospects of predicting impact on crop yields. This is particularly important for semi-arid West Africa where climate variability and drought threaten food security. Translating GCM outputs into attainable crop yields is difficult because GCM grid boxes are of larger scale than the processes governing yield, involving partitioning of rain among runoff, evaporation, transpiration, drainage and storage at plot scale. This study analyses the bias introduced to crop simulation when climatic data is aggregated spatially or in time, resulting in loss of relevant variation. A detailed case study was conducted using historical weather data for Senegal, applied to the crop model SARRA-H (version for millet). The study was then extended to a 10°N–17° N climatic gradient and a 31 year climate sequence to evaluate yield sensitivity to the variability of solar radiation and rainfall. Finally, a down-scaling model called LGO (Lebel–Guillot–Onibon), generating local rain patterns from grid cell means, was used to restore the variability lost by aggregation. Results indicate that forcing the crop model with spatially aggregated rainfall causes yield overestimations of 10–50% in dry latitudes, but nearly none in humid zones, due to a biased fraction of rainfall available for crop transpiration. Aggregation of solar radiation data caused significant bias in wetter zones where radiation was limiting yield. Where climatic gradients are steep, these two situations can occur within the same GCM grid cell. Disaggregation of grid cell means into a pattern of virtual synoptic stations having high-resolution rainfall distribution removed much of the bias caused by aggregation and gave realistic simulations of yield. It is concluded that coupling of GCM outputs with plot level crop models can cause large systematic errors due to scale incompatibility. These errors can be avoided by transforming GCM outputs, especially rainfall, to simulate the variability found at plot level. PMID:16433096

  1. Spatial and Temporal Patterns of Biocide Action against Staphylococcus epidermidis Biofilms▿ ‡

    PubMed Central

    Davison, William M.; Pitts, Betsey; Stewart, Philip S.

    2010-01-01

    The dynamic antimicrobial action of chlorine, a quaternary ammonium compound, glutaraldehyde, and nisin within biofilm cell clusters of Staphylococcus epidermidis was investigated using time-lapse confocal scanning laser microscopy. The technique allowed for the simultaneous imaging of changes in biofilm structure and disruption of cellular membrane integrity through the loss of an unbound fluorophore loaded into bacterial cells prior to antimicrobial challenge. Each of the four antimicrobial agents produced distinct spatial and temporal patterns of fluorescence loss. The antimicrobial action of chlorine was localized around the periphery of biofilm cell clusters. Chlorine was the only antimicrobial agent that caused any biofilm removal. Treatment with the quaternary ammonium compound caused membrane permeabilization that started at the periphery of cell clusters, then migrated steadily inward. A secondary pattern superimposed on the penetration dynamic suggested a subpopulation of less-susceptible cells. These bacteria lost fluorescence much more slowly than the majority of the population. Nisin caused a rapid and uniform loss of green fluorescence from all parts of the biofilm without any removal of biofilm. Glutaraldehyde caused no biofilm removal and also no loss of membrane integrity. Measurements of biocide penetration and action time at the center of cell clusters yielded 46 min for 10 mg liter−1 chlorine, 21 min for 50 mg liter−1 chlorine, 25 min for the quaternary ammonium compound, and 4 min for nisin. These results underscore the distinction between biofilm removal and killing and reinforce the critical role of biocide reactivity in determining the rate of biofilm penetration. PMID:20457816

  2. Knowledge and Cultural Beliefs of Mothers Regarding the Risk Factors of Infant Hearing Loss and Awareness of Audiology Services

    PubMed Central

    Govender, Samantha M.; Khan, Nasim Banu

    2017-01-01

    The aim of the paper is to describe the knowledge of mothers in Durban, South Africa, regarding risk factors of hearing loss in infants and their awareness of audiology services, and to describe their cultural beliefs about the risk factors for hearing loss in infants. A descriptive survey design with quantitative methods of analysis were used. Conveniently sampled mothers (n=102) receiving postnatal care for their infants from eight provincial clinics within Durban consented to participate, yielding a response rate of 48%. A questionnaire was used to collect the data and the Cronbach α was calculated yielding a score of 0.835, indicating good internal consistency and reliability of the questionnaire. Sixty percent of the mothers were aware of risk factors, such as middle ear infections, ototoxic medication and consumption of alcohol during pregnancy. Seventy percent were unaware that NICU/mechanical ventilation for more than 5 days, prematurity, rubella and jaundice are considered risk factors for hearing loss, implying a need to create awareness amongst mothers regarding such risk factors. Sixty percent (n=62) believed that bewitchment and ancestral curses can cause hearing loss. Cultural beliefs were associated with hearing loss, therefore, health professionals need to demonstrate cultural competence when providing audiology services, especially in a culturally and linguistically diverse countries such as South Africa. Although the mothers had an average knowledge about risk factors, two thirds did not know which professional to seek help from. There is a need to create awareness amongst mothers regarding the risk factors of infant hearing loss as well as audiology services in order to facilitate early detection and intervention. There is a need for health professionals to demonstrate cultural competence when working with their patients. PMID:28890772

  3. Knowledge and Cultural Beliefs of Mothers Regarding the Risk Factors of Infant Hearing Loss and Awareness of Audiology Services.

    PubMed

    Govender, Samantha M; Khan, Nasim Banu

    2017-06-23

    The aim of the paper is to describe the knowledge of mothers in Durban, South Africa, regarding risk factors of hearing loss in infants and their awareness of audiology services, and to describe their cultural beliefs about the risk factors for hearing loss in infants. A descriptive survey design with quantitative methods of analysis were used. Conveniently sampled mothers (n=102) receiving postnatal care for their infants from eight provincial clinics within Durban consented to participate, yielding a response rate of 48%. A questionnaire was used to collect the data and the Cronbach α was calculated yielding a score of 0.835, indicating good internal consistency and reliability of the questionnaire. Sixty percent of the mothers were aware of risk factors, such as middle ear infections, ototoxic medication and consumption of alcohol during pregnancy. Seventy percent were unaware that NICU/mechanical ventilation for more than 5 days, prematurity, rubella and jaundice are considered risk factors for hearing loss, implying a need to create awareness amongst mothers regarding such risk factors. Sixty percent (n=62) believed that bewitchment and ancestral curses can cause hearing loss. Cultural beliefs were associated with hearing loss, therefore, health professionals need to demonstrate cultural competence when providing audiology services, especially in a culturally and linguistically diverse countries such as South Africa. Although the mothers had an average knowledge about risk factors, two thirds did not know which professional to seek help from. There is a need to create awareness amongst mothers regarding the risk factors of infant hearing loss as well as audiology services in order to facilitate early detection and intervention. There is a need for health professionals to demonstrate cultural competence when working with their patients.

  4. The Effect of Gas Ion Bombardment on the Secondary Electron Yield of TiN, TiCN and TiZrV Coatings For Suppressing Collective Electron Effects in Storage Rings

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

    Le Pimpec, F.; /PSI, Villigen; Kirby, R.E.

    In many accelerator storage rings running positively charged beams, ionization of residual gas and secondary electron emission (SEE) in the beam pipe will give rise to an electron cloud which can cause beam blow-up or loss of the circulating beam. A preventative measure that suppresses electron cloud formation is to ensure that the vacuum wall has a low secondary emission yield (SEY). The SEY of thin films of TiN, sputter deposited Non-Evaporable Getters and a novel TiCN alloy were measured under a variety of conditions, including the effect of re-contamination from residual gas.

  5. Heat treatment of wheat straw by immersion in hot water decreases mushroom yield in Pleurotus ostreatus.

    PubMed

    Jaramillo Mejía, Santiago; Albertó, Edgardo

    2013-01-01

    The oyster mushroom, Pleurotus ostreatus, is cultivated worldwide. It is one of the most appreciated mushrooms due to its high nutritional value. Immersion of the substrate in hot water is one of the most popular and worldwide treatment used for mushroom farmers. It is cheap and easy to implement. To compare the yields obtained during mushroom production of P. ostreatus using different pre-treatments (immersion in hot water, sterilization by steam and the use of fungicide) to determine if they influence mushroom crop. Four different treatments of substrate (wheat straw) were carried out: (i) immersion in hot water (IHW); (ii) steam sterilization; (iii) chemical; and (iv) untreated. The residual water from the IHW treatment was used to evaluate the mycelium growth and the production of P. ostreatus. Carbendazim treatment produced highest yields (BE: 106.93%) while IHW produced the lowest BE with 75.83%. Sugars, N, P, K and Ca were found in residual water of IHW treatment. The residual water increased the mycelium growth but did not increase yields. We have proved that IHW treatment of substrate reduced yields at least 20% when compared with other straw treatments such as steam, chemical or untreated wheat straw. Nutrients like sugars, proteins and minerals were found in the residual water extract which is the resultant water where the immersion treatment is carried out. The loss of these nutrients would be the cause of yield decrease. Alternative methods to the use of IHW as treatment of the substrate should be considered to reduce economical loss. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  6. Frost trends and their estimated impact on yield in the Australian wheatbelt.

    PubMed

    Zheng, Bangyou; Chapman, Scott C; Christopher, Jack T; Frederiks, Troy M; Chenu, Karine

    2015-06-01

    Radiant spring frosts occurring during reproductive developmental stages can result in catastrophic yield loss for wheat producers. To better understand the spatial and temporal variability of frost, the occurrence and impact of frost events on rain-fed wheat production was estimated across the Australian wheatbelt for 1957-2013 using a 0.05 ° gridded weather data set. Simulated yield outcomes at 60 key locations were compared with those for virtual genotypes with different levels of frost tolerance. Over the last six decades, more frost events, later last frost day, and a significant increase in frost impact on yield were found in certain regions of the Australian wheatbelt, in particular in the South-East and West. Increasing trends in frost-related yield losses were simulated in regions where no significant trend of frost occurrence was observed, due to higher mean temperatures accelerating crop development and causing sensitive post-heading stages to occur earlier, during the frost risk period. Simulations indicated that with frost-tolerant lines the mean national yield could be improved by up to 20% through (i) reduced frost damage (~10% improvement) and (ii) the ability to use earlier sowing dates (adding a further 10% improvement). In the simulations, genotypes with an improved frost tolerance to temperatures 1 °C lower than the current 0 °C reference provided substantial benefit in most cropping regions, while greater tolerance (to 3 °C lower temperatures) brought further benefits in the East. The results indicate that breeding for improved reproductive frost tolerance should remain a priority for the Australian wheat industry, despite warming climates. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  7. Pricing Weather Index Insurance Based on Artificial Controlled Experiment - A Case Study of Cold Temperature for Early Rice in Jiangxi, China

    NASA Astrophysics Data System (ADS)

    SUN, Q.; Yang, Z.

    2017-12-01

    The growth of early rice is often threated by a phenomenon known as Grain Buds Cold, a period of anomalously cold temperature that occurs during the booting and flowering stage. Therefore, quantifying the impact of weather on crop yield is a core issue in design of weather index insurance. A high yield loss will lead to an increasing premium rate. In this paper, we explored a new way to investigate the relationship between yield loss rate and cold temperature durations. A two-year artificial controlled experiment was used to build logarithm and linear yield loss model. Moreover, an information diffusion model was applied to calculate the probability of different durations which lasting for 3-20 days. The results show that pure premium rates of logarithm yield loss model had better premium rates performance than that of linear yield loss model. The premium rates of Grain Buds Cold Weather Index Insurance fluctuated between 7.085% and 10.151% in Jiangxi Province. Compared with common statistical methods, the artificial controlled experiment provides an easier and more robust way to determine the relationship between yield and single meteorological factor. Meanwhile, this experiment would be very important for some regions where were lacking in historical yield data and climate data and could help farmers cope with extreme cold weather risks under varying weather conditions.

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

    Lisitsyn, V. M.; Stepanov, S. A., E-mail: stepanovsa@tpu.ru; Yangyang, Ju

    In most promising widespread gallium nitride based LEDs emission is generated in the blue spectral region with a maximum at about 450 nm which is converted to visible light with the desired spectrum by means of phosphor. The thermal energy in the conversion is determined by the difference in the energies of excitation and emission quanta and the phosphor quantum yield. Heat losses manifest themselves as decrease in the luminous efficacy. LED heating significantly reduces its efficiency and life. In addition, while heating, the emission generation output and the efficiency of the emission conversion decrease. Therefore, the reduction of the energymore » losses caused by heating is crucial for LED development. In this paper, heat losses in phosphor-converted LEDs (hereinafter chips) during spectrum conversion are estimated. The limit values of the luminous efficacy for white LEDs are evaluated.« less

  9. Crop yield changes induced by emissions of individual climate-altering pollutants

    NASA Astrophysics Data System (ADS)

    Shindell, Drew T.

    2016-08-01

    Climate change damages agriculture, causing deteriorating food security and increased malnutrition. Many studies have examined the role of distinct physical processes, but impacts have not been previously attributed to individual pollutants. Using a simple model incorporating process-level results from detailed models, here I show that although carbon dioxide (CO2) is the largest driver of climate change, other drivers appear to dominate agricultural yield changes. I calculate that anthropogenic emissions to date have decreased global agricultural yields by 9.5 ± 3.0%, with roughly 93% stemming from non-CO2 emissions, including methane (-5.2 ± 1.7%) and halocarbons (-1.4 ± 0.4%). The differing impacts stem from atmospheric composition responses: CO2 fertilizes crops, offsetting much of the loss induced by warming; halocarbons do not fertilize; methane leads to minimal fertilization but increases surface ozone which augments warming-induced losses. By the end of the century, strong CO2 mitigation improves agricultural yields by ˜3 ± 5%. In contrast, strong methane and hydrofluorocarbon mitigation improve yields by ˜16 ± 5% and ˜5 ± 4%, respectively. These are the first quantitative analyses to include climate, CO2 and ozone simultaneously, and hence, additional studies would be valuable. Nonetheless, as policy makers have leverage over pollutant emissions rather than isolated processes, the perspective presented here may be more useful for decision making than that in the prior work upon which this study builds. The results suggest that policies should target a broad portfolio of pollutant emissions in order to optimize mitigation of societal damages.

  10. Body live weight and milk production parameters in the Majorera and Palmera goat breeds from the Canary Islands: influence of weight loss.

    PubMed

    Lérias, Joana R; Hernández-Castellano, Lorenzo E; Morales-Delanuez, Antonio; Araújo, Susana S; Castro, Noemí; Argüello, Anastasio; Capote, Juan; Almeida, André M

    2013-11-01

    Seasonal weight loss (SWL), caused by poor quality pastures during the dry season, is the major limitation to animal production in the tropics. One of the ways to counter this problem is to breed animals that show tolerance to SWL. The objective of this study was to understand the effect of feed restriction in milk production and live weight (LW) evolution in two goat breeds, with different levels of adaptation to nutritional stress: the Majorera (considered to be tolerant) and the Palmera (considered to be susceptible). A total of ten animals per breed were used. Animals were divided in four groups (two for each breed): a restricted group (restricted diet) and a control group. LW and milk yield parameters were recorded through a trial that lasted 23 days in total. Overall, there were no significant differences between both restricted groups, regarding neither LW nor milk yield reductions (LW reduction 13 % and milk yield reduction of 87 % for both restricted groups). In what concerns control groups, there were no significant differences between breeds, thought there were different increments at the end of the trial for both breeds regarding LW (6 and 4 %, for Majorera and Palmera, respectively) and milk yield (28 and 8 %, respectively for Majorera and Palmera). The lack of statistically significant differences between Palmera and Majorera LW and milk yields in restricted groups may be due to the fact that the controlled trial does not replicate harsh field conditions, in which Majorera would excel, and the stress induced by those differences.

  11. Long-term variation of Surface Ozone, NO2, temperature and relative humidity on crop yield over Andhra Pradesh (AP), India

    NASA Astrophysics Data System (ADS)

    Arunachalam, M. S.; Obili, Manjula; Srimurali, M.

    2016-07-01

    Long-term variation of Surface Ozone, NO2, Temperature, Relative humidity and crop yield datasets over thirteen districts of Andhra Pradesh(AP) has been studied with the help of OMI, MODIS, AIRS, ERA-Interim re-analysis and Directorate of Economics and Statistics (DES) of AP. Inter comparison of crop yield loss estimates according to exposure metrics such as AOT40 (accumulated ozone exposure over a threshold of 40) and non-linear variation of surface temperature for twenty and eighteen varieties of two major crop growing seasons namely, kharif (April-September) and rabi (October-March), respectively has been made. Study is carried to establish a new crop-yield-exposure relationship for different crop cultivars of AP. Both ozone and temperature are showing a correlation coefficient of 0.66 and 0.87 with relative humidity; and 0.72 and 0.80 with NO2. Alleviation of high surface ozone results in high food security and improves the economy thereby reduces the induced warming of the troposphere caused by ozone. Keywords: Surface Ozone, NO2, Temperature, Relative humidity, Crop yield, AOT 40.

  12. In vitro non-enzymatic ribation reduces post-yield strain accommodation in cortical bone.

    PubMed

    Willett, Thomas L; Sutty, Sibi; Gaspar, Anne; Avery, Nick; Grynpas, Marc

    2013-02-01

    Non-enzymatic glycation (NEG) and advanced glycation endproducts (AGEs) may contribute to bone fragility in various diseases, ageing, and other conditions by modifying bone collagen and causing degraded mechanical properties. In this study, we sought to further understand how collagen modification in an in vitro non-enzymatic ribation model leads to loss of cortical bone toughness. Previous in vitro studies using non-enzymatic ribation reported loss of ductility in the cortical bone. Increased crosslinking is most commonly blamed for these changes; however, some studies report positive correlations between measures of total collagen crosslinking and work-to-fracture/toughness measurements whilst correlations between general NEG and measures of ductility are often negative. Fifteen bone beam triplets were cut from bovine metatarsi. Each provided one native non-incubated control, one incubated control and one ribated specimen. Incubation involved simulated body fluid±ribose for fourteen days at 37°C. Pentosidine and pyridinoline crosslinks were measured using HPLC. Three-point bending tests quantified mechanical properties. Fracture surfaces were examined using scanning electron microscopy. The effects of ribation on bone collagen molecular stability and intermolecular connectivity were investigated using differential scanning calorimetry and hydrothermal isometric tension testing. Ribation caused increased non-enzymatic collagen modification and pentosidine content (16mmol/mol collagen) and inferior post-yield mechanical behaviour, especially post-yield strain and flexural toughness. Fracture surfaces were smoother with less collagen fibril deformation or tearing than observed in controls. In the ribated group only, pentosidine content and thermomechanical measures of crosslinking were positively correlated with measures of strain accommodation and energy absorption before failure. Non-enzymatic ribation and the resulting modifications reduce cortical bone pseudo-plasticity through a reduced capacity for post-yield strain accommodation. However, the positive correlations we have found suggest that increased crosslinking may not provide a complete explanation for this embrittlement. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Exponential yield sensitivity to long-wavelength asymmetries in three-dimensional simulations of inertial confinement fusion capsule implosions

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

    Haines, Brian M., E-mail: bmhaines@lanl.gov

    2015-08-15

    In this paper, we perform a series of high-resolution 3D simulations of an OMEGA-type inertial confinement fusion (ICF) capsule implosion with varying levels of initial long-wavelength asymmetries in order to establish the physical energy loss mechanism for observed yield degradation due to long-wavelength asymmetries in symcap (gas-filled capsule) implosions. These simulations demonstrate that, as the magnitude of the initial asymmetries is increased, shell kinetic energy is increasingly retained in the shell instead of being converted to fuel internal energy. This is caused by the displacement of fuel mass away from and shell material into the center of the implosion duemore » to complex vortical flows seeded by the long-wavelength asymmetries. These flows are not fully turbulent, but demonstrate mode coupling through non-linear instability development during shell stagnation and late-time shock interactions with the shell interface. We quantify this effect by defining a separation lengthscale between the fuel mass and internal energy and show that this is correlated with yield degradation. The yield degradation shows an exponential sensitivity to the RMS magnitude of the long-wavelength asymmetries. This strong dependence may explain the lack of repeatability frequently observed in OMEGA ICF experiments. In contrast to previously reported mechanisms for yield degradation due to turbulent instability growth, yield degradation is not correlated with mixing between shell and fuel material. Indeed, an integrated measure of mixing decreases with increasing initial asymmetry magnitude due to delayed shock interactions caused by growth of the long-wavelength asymmetries without a corresponding delay in disassembly.« less

  14. Simulation of Nitrogen and Phosphorus Losses in Loess Landforms of Northern Iran

    NASA Astrophysics Data System (ADS)

    Kiani, F.; Behtarinejad, B.; Najafinejad, A.; Kaboli, R.

    2018-02-01

    Population growth, urban expansion and intensive agriculture and thus increased use of fertilizers aimed at increasing the production capacity cause extensive loss of nutrients such as nitrogen and phosphorus and lead to reduced quality of soil and water. Therefore, identification of nutrients in the soil and their potential are essential. The aim of this study was to evaluate the capability of the SWAT model in simulating runoff, sediment, and nitrogen and phosphorus losses in Tamer catchment. Runoff and sediment measured at Tamar gauging station were used to calibrate and validate the model. Simulated values were generally consistent with the data observed during calibration and validation period (0.6 < R 2 and 0.5 < NS). In the case of nitrogen loss, the model performed an almost good simulation (0.6 < R 2 and 0.47 < NS), but phosphorus simulation yielded better results (0.76 < R 2 and 0.66 < NS). The results showed that cultivated lands had higher loss of nitrogen and phosphorus than other types of land use. Among the various forms of nitrogen and phosphorus, the loss of organic nitrogen and nitrate and soluble phosphorus and mineral phosphorus attached to the sediments showed the greatest sensitivity to the type of land use. Results also showed that the average nutrient loss caused by erosion in this catchment, was 6.99 kg/ha for nitrogen, 0.35 kg/ha for nitrate, 1.3 kg/ha for organic phosphorus, 0.015 kg/ha for soluble phosphorus, and 0.45 kg/ha for mineral phosphorus.

  15. Defect detection and control in an analog CMOS process

    NASA Astrophysics Data System (ADS)

    Taucher, Franz; Evans, Ivor R.

    1996-09-01

    Over the last 12 months, Austria Mikro Systeme has installed an even more rigorous system of defect density measurement, monitoring and control in its facility at Unterpremstatten. To accomplish this, 2 test devices (Medusa 1 and 2) were designed which allow possible defects in all layers of the process to be located. These devices are 8 by 9 mm2 in area and contain various structures to quantify the density of defects causing continuity, bridging and inter-layer isolation failure. The devices move through the waferfab receiving all process steps with the usual handling and operator procedures, from which it is clear, that the density of defects measured is representative of that of normal production material. The wafers are tested electrically using a Keithley S450, and data analysis is done with RS1 and EXCEL. By using yield models available from the literature, the correspondence in yield estimates made in this way and actual production yields were generally within 3%. Applying this technique allows the yield loss mechanisms to be isolated and then prioritized. The chipset identified several areas within the process which required special attention. These included implant optimization to reduce gate oxide damage, defect reduction in the metal-etch process, increased leakage currents caused by implant channeling and second poly etch-control to avoid 'bridging' around poly 1 periphery. Successful actions at these points have led to a significant improvement in wafer probe yields at Austria Mikro Systeme.

  16. Wireworms’ Management: An Overview of the Existing Methods, with Particular Regards to Agriotes spp. (Coleoptera: Elateridae)

    PubMed Central

    Barsics, Fanny; Haubruge, Eric; Verheggen, François J.

    2013-01-01

    Wireworms (Coleoptera: Elateridae) are important soil dwelling pests worldwide causing yield losses in many crops. The progressive restrictions in the matter of efficient synthetic chemicals for health and environmental care brought out the need for alternative management techniques. This paper summarizes the main potential tools that have been studied up to now and that could be applied together in integrated pest management systems and suggests guidelines for future research. PMID:26466799

  17. Modeling Long-Term Corn Yield Response to Nitrogen Rate and Crop Rotation

    PubMed Central

    Puntel, Laila A.; Sawyer, John E.; Barker, Daniel W.; Dietzel, Ranae; Poffenbarger, Hanna; Castellano, Michael J.; Moore, Kenneth J.; Thorburn, Peter; Archontoulis, Sotirios V.

    2016-01-01

    Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) compare crop model-based techniques in estimating optimal N rate for corn; and (c) utilize the calibrated model to explain factors causing year to year variability in yield and optimal N. Results indicated that the model simulated well long-term crop yields response to N (relative root mean square error, RRMSE of 19.6% before and 12.3% after calibration), which provided strong evidence that important soil and crop processes were accounted for in the model. The prediction of EONR was more complex and had greater uncertainty than the prediction of crop yield (RRMSE of 44.5% before and 36.6% after calibration). For long-term site mean EONR predictions, both calibrated and uncalibrated versions can be used as the 16-year mean differences in EONR’s were within the historical N rate error range (40–50 kg N ha-1). However, for accurate year-by-year simulation of EONR the calibrated version should be used. Model analysis revealed that higher EONR values in years with above normal spring precipitation were caused by an exponential increase in N loss (denitrification and leaching) with precipitation. We concluded that long-term experimental data were valuable in testing and refining APSIM predictions. The model can be used as a tool to assist N management guidelines in the US Midwest and we identified five avenues on how the model can add value toward agronomic, economic, and environmental sustainability. PMID:27891133

  18. Modeling Long-Term Corn Yield Response to Nitrogen Rate and Crop Rotation.

    PubMed

    Puntel, Laila A; Sawyer, John E; Barker, Daniel W; Dietzel, Ranae; Poffenbarger, Hanna; Castellano, Michael J; Moore, Kenneth J; Thorburn, Peter; Archontoulis, Sotirios V

    2016-01-01

    Improved prediction of optimal N fertilizer rates for corn ( Zea mays L. ) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean ( Glycine max L. ) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha -1 ) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) compare crop model-based techniques in estimating optimal N rate for corn; and (c) utilize the calibrated model to explain factors causing year to year variability in yield and optimal N. Results indicated that the model simulated well long-term crop yields response to N (relative root mean square error, RRMSE of 19.6% before and 12.3% after calibration), which provided strong evidence that important soil and crop processes were accounted for in the model. The prediction of EONR was more complex and had greater uncertainty than the prediction of crop yield (RRMSE of 44.5% before and 36.6% after calibration). For long-term site mean EONR predictions, both calibrated and uncalibrated versions can be used as the 16-year mean differences in EONR's were within the historical N rate error range (40-50 kg N ha -1 ). However, for accurate year-by-year simulation of EONR the calibrated version should be used. Model analysis revealed that higher EONR values in years with above normal spring precipitation were caused by an exponential increase in N loss (denitrification and leaching) with precipitation. We concluded that long-term experimental data were valuable in testing and refining APSIM predictions. The model can be used as a tool to assist N management guidelines in the US Midwest and we identified five avenues on how the model can add value toward agronomic, economic, and environmental sustainability.

  19. Effects of geoengineering on crop yields

    NASA Astrophysics Data System (ADS)

    Pongratz, J.; Lobell, D. B.; Cao, L.; Caldeira, K.

    2011-12-01

    The potential of "solar radiation management" (SRM) to reduce future climate change and associated risks has been receiving significant attention in scientific and policy circles. SRM schemes aim to reduce global warming despite increasing atmospheric CO2 concentrations by diminishing the amount of solar insolation absorbed by the Earth, for example, by injecting scattering aerosols into the atmosphere. Climate models predict that SRM could fully compensate warming at the global mean in a high-CO2 world. While reduction of global warming may offset a part of the predicted negative effects of future climate change on crop yields, SRM schemes are expected to alter regional climate and to have substantial effects on climate variables other than temperature, such as precipitation. It has therefore been warned that, overall, SRM may pose a risk to food security. Assessments of benefits and risks of geoengineering are imperative, yet such assessments are only beginning to emerge; in particular, effects on global food security have not previously been assessed. Here, for the first time, we combine climate model simulations with models of crop yield responses to climate to assess large-scale changes in yields and food production under SRM. In most crop-growing regions, we find that yield losses caused by climate changes are substantially reduced under SRM as compared with a non-geoengineered doubling of atmospheric CO2. Substantial yield losses with SRM are only found for rice in high latitudes, where the limits of low temperatures are no longer alleviated. At the same time, the beneficial effect of CO2-fertilization on plant productivity remains active. Overall therefore, SRM in our models causes global crop yields to increase. We estimate the direct effects of climate and CO2 changes on crop production, and do not quantify effects of market dynamics and management changes. We note, however, that an SRM deployment would be unlikely to maintain the economic status quo, as market shares of agricultural output may change with the different spatial pattern of climate change. More importantly, geoengineering by SRM does not address a range of other detrimental consequences of climate change, such as ocean acidification, which could also affect food security via effects on marine food webs. Finally, SRM poses substantial anticipated and unanticipated risks by interfering with complex, not fully understood systems. Therefore, despite potential positive effects of SRM on crop yields, the most certain way to reduce climate risks to global food security is to reduce emissions of greenhouse gases.

  20. Assessment of crop yield losses in Punjab and Haryana using two years of continuous in-situ ozone measurements

    NASA Astrophysics Data System (ADS)

    Sinha, B.; Singh Sangwan, K.; Maurya, Y.; Kumar, V.; Sarkar, C.; Chandra, B. P.; Sinha, V.

    2015-01-01

    In this study we use a high quality dataset of in-situ ozone measurements at a suburban site called Mohali in the state of Punjab to estimate ozone related crop yield losses for wheat, rice, cotton and maize for Punjab and the neighbouring state Haryana for the years 2011-2013. We inter-compare crop yield loss estimates according to different exposure metrics such as AOT40 and M7 for the two major crop growing seasons of Kharif (June-October) and Rabi (November-April) and establish a new crop yield exposure relationship for South Asian wheat and rice cultivars. These are a factor of two more sensitive to ozone induced crop yield losses compared to their European and American counterparts. Relative yield losses based on the AOT40 metrics ranged from 27-41% for wheat, 21-26% for rice, 9-11% for maize and 47-58% for cotton. Crop production losses for wheat amounted to 20.8 million t in fiscal year 2012-2013 and 10.3 million t in fiscal year 2013-2014 for Punjab and Haryana jointly. Crop production losses for rice totalled 5.4 million t in fiscal year 2012-2013 and 3.2 million t year 2013-2014 for Punjab and Haryana jointly. The Indian National Food Security Ordinance entitles ~ 820 million of India's poor to purchase about 60 kg of rice/wheat per person annually at subsidized rates. The scheme requires 27.6 Mt of wheat and 33.6 Mt of rice per year. Mitigation of ozone related crop production losses in Punjab and Haryana alone could provide >50% of the wheat and ~10% of the rice required for the scheme. The total economic cost losses in Punjab and Haryana amounted to USD 6.5 billion in the fiscal year 2012-2013 and USD 3.7 billion in the fiscal year 2013-2014. This economic loss estimate represents a very conservative lower limit based on the minimum support price of the crop, which is lower than the actual production costs. The upper limit for ozone related crop yield losses in entire India currently amounts to 3.5-20% of India's GDP. Mitigation of high surface ozone would require relatively little investment in comparison to economic losses incurred presently. Therefore, ozone mitigation can yield massive benefits in terms of ensuring food security and boosting the economy. Co-benefits of ozone mitigation also include a decrease in the ozone related mortality, morbidity and a reduction of the ozone induced warming in the lower troposphere.

  1. Climate change impacts on coffee rust disease

    NASA Astrophysics Data System (ADS)

    Alfonsi, W. M. V.; Koga-Vicente, A.; Pinto, H. S.; Alfonsi, E. L., Sr.; Coltri, P. P.; Zullo, J., Jr.; Patricio, F. R.; Avila, A. M. H. D.; Gonçalves, R. R. D. V.

    2016-12-01

    Changes in climate conditions and in extreme weather events may affect the food security due to impacts in agricultural production. Despite several researches have been assessed the impacts of extremes in yield crops in climate change scenarios, there is the need to consider the effects in pests and diseases which increase losses in the sector. Coffee Arabica is an important commodity in world and plays a key role in Brazilian agricultural exports. Although the coffee crop has a world highlight, its yield is affected by several factors abiotic or biotic. The weather as well pests and diseases directly influence the development and coffee crop yield. These problems may cause serious damage with significant economic impacts. The coffee rust, caused by the fungus Hemileia vastarix,is among the diseases of greatest impact for the crop. The disease emerged in Brazil in the 70s and is widely spread in all producing regions of coffee in Brazil, and in the world. Regions with favorable weather conditions for the pathogen may exhibit losses ranging from 30% to 50% of the total grain production. The evaluation of extreme weather events of coffee rust disease in futures scenarios was carried out using the climatic data from CMIP5 models, data field of coffee rust disease incidence and, incubation period simulation data for Brazilian municipalities. Two Regional Climate Models were selected, Eta-HadGEM2-ES and Eta-MIROC5, and the Representative Concentration Pathways 8.5 w/m2 was adopted. The outcomes pointed out that in these scenarios the period of incubation tends to decrease affecting the coffee rust disease incidence, which tends to increase. Nevertheless, the changing in average trends tends to benefit the reproduction of the pathogen. Once the temperature threshold for the disease reaches the adverse conditions it may be unfavorable for the incidence.

  2. Pacific halibut bycatch in Pacific cod fisheries in the Bering Sea: an analysis to evaluate area-time management

    NASA Astrophysics Data System (ADS)

    Adlerstein, Sara A.; Trumble, Robert J.

    1998-03-01

    Mortality of discarded Pacific halibut bycatch from Pacific cod fisheries in the Bering Sea leads to significant losses in the halibut setline and in the Pacific cod fisheries. The commercial halibut fishery loses yield because of catch limit reductions to compensate the resource for lost spawning potential and because halibut killed as bycatch will not be available for subsequent harvest, and the cod fisheries may lose harvest if they reach a bycatch mortality limit before reaching allowed catch. In this study, significant differences in Pacific halibut bycatch rates and associated yield losses were found among months and areas of the Bering Sea in the longline and trawl fisheries for Pacific cod in 1990-1992. Bycatch rates were usually highest in late spring and early summer and in areas close to the Unimak Pass. With the exception of 1992, yield loss in the longline fishery was around 1 kg per kg of bycatch mortality, irrespective of where or when bycatch occurred. In the trawl fishery, loss of halibut yield varied from 1 to 4 kg per kg of bycatch mortality. Highest halibut net yield losses per tonne of groundfish harvest usually coincided with highest bycatch rates. When both fisheries operated in one area, trawl bycatch often imposed higher yield losses than longline bycatch, despite lower bycatch rates. Bycatch was affected by the strong 1987 halibut year class. Highest bycatch and yield loss rates occurred in the trawl fishery in 1990 and 1991 when the population was dominated by halibut age-3 and -4, and in the longline fishery in 1992 as fish reached age-5.

  3. Manure incorporation reduces environmental nitrogen loss while sustaining crop productivity in the subtropical wheat-maize rotation system: A comprehensive study of nitrogen cycling and balance

    NASA Astrophysics Data System (ADS)

    Zhou, Minghua; Zhu, Bo; Butterbach-Bahl, klaus; Brüggemann, Nicolas

    2016-04-01

    Balancing nitrogen (N) budgets of agricultural systems is essential for sustaining yields at lower environmental costs. The knowledge, however, of total N budgets of agricultural systems including all N fluxes is still rare in the literature. Here, we applied a combination of monitoring in situ N fluxes and field 15N tracer and 15N isotope dilution techniques to investigate the effects of different N fertilizers (control, synthetic fertilizer, 60% synthetic fertilizer N plus 40% pig manure N, pig manure only applied at the same N rate 280 kg N ha-1 yr-1) on N pools, cycling processes, fluxes and total N balances in a subtropical wheat-maize rotation system of China. Nitrate leaching and NH3 volatilization were main hydrological and gaseous N loss pathways, respectively. The warm and wet maize season was associated with significantly larger environmental N losses than the cooler and drier wheat season. The field 15N tracing experiment showed that the wheat system had high N retention capacity (˜50% of 15N application) but with short residence time. I.e. 90% of soil residual 15N labelled fertilizer in the wheat system were utilized by plants or lost to the environment in the subsequent maize season. Our annual total N balances of the different treatments revealed that combined synthetic and organic fertilization or manure only maintained the same level of yields and led to significantly lower N losses and higher N retention, even though larger NH3 volatilization losses were caused by manure incorporation. Thus, our study suggests that a combination of synthetic and organic N fertilizers is suitable for sustaining agricultural productivity while reducing environmental N losses through fostering interactions between the soil C and N cycle.

  4. Phosphatidylcholine synthesis is required for optimal function of Legionella pneumophila virulence determinants.

    PubMed

    Conover, Gloria M; Martinez-Morales, Fernando; Heidtman, Matthew I; Luo, Zhao-Qing; Tang, May; Chen, Cui; Geiger, Otto; Isberg, Ralph R

    2008-02-01

    The function of phosphatidylcholine (PC) in the bacterial cell envelope remains cryptic. We show here that productive interaction of the respiratory pathogen Legionella pneumophila with host cells requires bacterial PC. Synthesis of the lipid in L. pneumophila was shown to occur via either phospholipid N-methyltransferase (PmtA) or phosphatidylcholine synthase (PcsA), but the latter pathway was demonstrated to be of predominant importance. Loss of PC from the cell envelope caused lowered yields of L. pneumophila within macrophages as well as loss of high multiplicity cytotoxicity, while mutants defective in PC synthesis could be complemented either by reintroduction of PcsA or by overproduction of PmtA. The lowered yields and reduced cytotoxicity in mutants with defective PC biosynthesis were due to three related defects. First, there was a poorly functioning Dot/Icm apparatus, which delivers substrates required for intracellular growth into the cytosol of infected cells. Second, there was reduced bacterial binding to macrophages, possibly due to loss of PC or a PC derivative on the bacterium that is recognized by the host cell. Finally, strains lacking PC had low steady-state levels of flagellin protein, a deficit that had been previously associated with the phenotypes of lowered cytotoxicity and poor cellular adhesion.

  5. [Progressive noise induced hearing loss caused by hearing AIDS, a dilemma for the worker and the expert alike].

    PubMed

    Feldmann, H

    2001-12-01

    Investigating cases of noise induced hearing loss the expert is often confronted with the situation that the hearing loss is progressive although the noise exposure has been reduced to almost non-damaging levels. Other causes such as age, hereditary deafness, head injuries, blasts, internal diseases can be excluded. Hearing aids as sources of damaging noise? By consulting the protocol of the hearing-aid acoustician and by own examinations the expert should obtain the following data: loudness level that yields best discrimination score of speech; level of discomfort for tones and speech, discrimination score that is achieved under free field condition with a speech level of 65 dB, using the hearing aids. Furthermore he should explore the circumstances under which the hearing aids are used: how many hours per day, at what occasions etc.? It is likely that in using the hearing aids they are adjusted to emit an intensity level identical to the one yielding the optimal discrimination score. If this e. g. is 100 dB and the hearing aids are used for 2 hours per day this would be equivalent to an exposure to industrial noise of 94 dB (A) for 8 hours daily without ear protection. Among all individuals working under industrial noise exposure today only about 1 - 2 % having unusually vulnerable inner ears will suffer a noise induced hearing loss. On the other hand workers in industrial noise are accustomed to loud noise levels, usually have a raised threshold of discomfort and therefore are likely to adjust their hearing aids to such high intensities. The expert will have to decide whether in an individual case the industrial noise exposure or the use of the hearing aids is the dominant risk for further damage. The consequences in respect to the regulations of the workers' health insurance are discussed.

  6. Phenalenone-type phytoalexins mediate resistance of banana plants (Musa spp.) to the burrowing nematode Radopholus similis

    PubMed Central

    Hölscher, Dirk; Dhakshinamoorthy, Suganthagunthalam; Alexandrov, Theodore; Becker, Michael; Bretschneider, Tom; Buerkert, Andreas; Crecelius, Anna C.; De Waele, Dirk; Elsen, Annemie; Heckel, David G.; Heklau, Heike; Hertweck, Christian; Kai, Marco; Knop, Katrin; Krafft, Christoph; Maddula, Ravi K.; Matthäus, Christian; Popp, Jürgen; Schneider, Bernd; Schubert, Ulrich S.; Sikora, Richard A.; Svatoš, Aleš; Swennen, Rony L.

    2014-01-01

    The global yield of bananas—one of the most important food crops—is severely hampered by parasites, such as nematodes, which cause yield losses up to 75%. Plant–nematode interactions of two banana cultivars differing in susceptibility to Radopholus similis were investigated by combining the conventional and spatially resolved analytical techniques 1H NMR spectroscopy, matrix-free UV-laser desorption/ionization mass spectrometric imaging, and Raman microspectroscopy. This innovative combination of analytical techniques was applied to isolate, identify, and locate the banana-specific type of phytoalexins, phenylphenalenones, in the R. similis-caused lesions of the plants. The striking antinematode activity of the phenylphenalenone anigorufone, its ingestion by the nematode, and its subsequent localization in lipid droplets within the nematode is reported. The importance of varying local concentrations of these specialized metabolites in infected plant tissues, their involvement in the plant’s defense system, and derived strategies for improving banana resistance are highlighted. PMID:24324151

  7. Thermal removal of pyrene contamination from soil: basic studies and environmental health implications.

    PubMed Central

    Saito, H H; Bucalá, V; Howard, J B; Peters, W A

    1998-01-01

    Effects of temperature (400-1000 degrees C) and rate of heating to 550 degrees C (100, 1000, 5000 degrees C/sec) on reduction of pyrene contamination in a Superfund-related soil and on yields of volatile products (tars, CO, CO2, methane, acetylene, ethylene) have been measured. Fifty (+/- 3)-milligram thin layers (less than or equal to 150 micron) of 63- to 125-micron soil particles, neat (i.e., without exogenous chemicals), or pretreated with 4.75 wt% of pyrene, were heated for about 1 to 6 sec, under 3 psig (pounds per in.(2) gauge) of helium in a 12-liter sealed chamber. Pyrene removal, defined as the difference in weight loss of neat versus contaminated soil, was virtually immune to heating rate but increased strongly with increasing temperature, approaching 100% at about 530 degrees C. However, for pyrenepolluted soil, excess soil weight loss and modified CO yields were observed above about 500 degrees C for a 1000 degrees C/sec heating rate. These observations suggest that soil chemical reactions with pyrene or pyrene decomposition products augment soil volatilization. Consequently at elevated temperatures, the difference in weight loss protocol may overestimate polycyclic aromatic hydrocarbon (PAH) removal from soil. Increasing heating rate caused yields of CO, CO(2), and acetylene from pyrene-polluted soil to pass through maxima. Heating neat or contaminated soil resulted in at least two gaseous products of particular environmental interest:acetylene, a precursor to PAH in thermal synthesis, and CO, a toxin to human hemoglobin. Images Figure 1 Figure 2 PMID:9703498

  8. Carbon-negative biofuels from low-input high-diversity grassland biomass.

    PubMed

    Tilman, David; Hill, Jason; Lehman, Clarence

    2006-12-08

    Biofuels derived from low-input high-diversity (LIHD) mixtures of native grassland perennials can provide more usable energy, greater greenhouse gas reductions, and less agrichemical pollution per hectare than can corn grain ethanol or soybean biodiesel. High-diversity grasslands had increasingly higher bioenergy yields that were 238% greater than monoculture yields after a decade. LIHD biofuels are carbon negative because net ecosystem carbon dioxide sequestration (4.4 megagram hectare(-1) year(-1) of carbon dioxide in soil and roots) exceeds fossil carbon dioxide release during biofuel production (0.32 megagram hectare(-1) year(-1)). Moreover, LIHD biofuels can be produced on agriculturally degraded lands and thus need to neither displace food production nor cause loss of biodiversity via habitat destruction.

  9. Quaternary IPM (integrated pest management)--concept for the control of powdery mildew in sugar beets.

    PubMed

    Wolf, P F J; Verreet, A

    2008-01-01

    Powdery mildew, caused by Erysiphe betae (Vanha) Weltzien, may be assumed as an important leaf disease in sugar beet growing areas of central Europe. Although the causal agent is mainly adapted to arid climatic zones, the disease is appearing every year, where the extent of infection is mainly dependent on weather conditions and susceptibility of cultivar. The losses caused by powdery mildew seldom exceed 10% of sugar yield; moreover, losses are likely only under the condition that the epidemic onset occurs before end-August. Nevertheless, the epidemic onset varies in a wide range, as there are years with high incidence followed by growing periods without severe infection. Therefore, in order to have a flexible control of the disease, where the use of fungicides could be minimised to an essential amount, a quaternary IPM (Integrated Pest Management) -concept was developed. The development is based on epidemiological field studies (Germany, 1993-2004, n = 76) of sugar beet leaf diseases under variation of year, site and cultivar. Efficacy of fungicide treatment timing was assessed in relation to the epidemic development. Comparison of treatments comprised fungicide sprays carried out from disease initiation till later stages of the epidemic. Additionally, the assessments were performed in relation to an untreated and a healthy control--the latter was three times treated according to a treatment regime with three to four week intervals. The effect of different application timings was measured by the potential of disease and yield loss control. The quaternary concept combines the advantages of four elements in order to compensate the constraints of the single tools: The period without disease risk is determined by a so-called negative-prognosis (i). First symptoms appear in the period from mid-July till the beginning of September. If disease initiation cannot be excluded, field observations by a sample of 100 leaves are advised. The disease scores enable the appliance of action thresholds (ii). The latter are defined as early stages of the epidemic in order to optimize the efficiency of fungicide treatments. For an initial treatment a threshold of 5% infected leaves is defined. However, incidence in the height of action thresholds is not affecting an instant damage. The stage when a sugar beet is damaged effectively is rather defined by the economic damage threshold (iii). As a consequence, because exceeding of action threshold doesn't implicate immediate yield risk, loss prediction (iv) is required. The loss prediction assesses the likelihood of disease progress will exceed the economic damage threshold at harvest time. Loss risk is existent in case of action threshold exceeding till mid-August if cultivar susceptibility is low respectively end-August if susceptibility is high.

  10. Chemical Changes during Maize Tissue Aging and Its Relationship with Mediterranean Corn Borer Resistance.

    PubMed

    López-Malvar, Ana; Ordás, Bernardo; Souto, Carlos; Encina, Antonio; Malvar, Rosa A; Santiago, Rogelio

    2017-10-25

    The Mediterranean corn borer (MCB), Sesamia nonagrioides Lef, is an important pest of maize in temperate areas, causing significant stalk lodging and yield losses. The main goals of this study were to determine possible changes in chemical traits (phenols, flavonoids, anthocyanins, sugars, fibers, and lignin) during plant development after the flowering stage and to assess how those traits may differ in diverse genotypes of maize, such as MCB resistant and susceptible. Higher values for some particular traits in more mature tissues seemed to increase their effectiveness against the MCB attack. A decreased amount of borer damage in the field was recorded in the resistant inbred line and in older tissues (7.90 cm vs 31.70 cm as the mean for the stalk tunnel length). In accordance with these results, the resistant inbred line showed a higher degree of hemicellulose cross-linkage (due to ferulic and diferulic acids), higher soluble sugar content, and higher stalk strength. The use of resistant varieties and early sowings is highly recommended as an integrated approach to reduce the yield losses produced by this pest.

  11. Estimating milk yield and value losses from increased somatic cell count on US dairy farms.

    PubMed

    Hadrich, J C; Wolf, C A; Lombard, J; Dolak, T M

    2018-04-01

    Milk loss due to increased somatic cell counts (SCC) results in economic losses for dairy producers. This research uses 10 mo of consecutive dairy herd improvement data from 2013 and 2014 to estimate milk yield loss using SCC as a proxy for clinical and subclinical mastitis. A fixed effects regression was used to examine factors that affected milk yield while controlling for herd-level management. Breed, milking frequency, days in milk, seasonality, SCC, cumulative months with SCC greater than 100,000 cells/mL, lactation, and herd size were variables included in the regression analysis. The cumulative months with SCC above a threshold was included as a proxy for chronic mastitis. Milk yield loss increased as the number of test days with SCC ≥100,000 cells/mL increased. Results from the regression were used to estimate a monetary value of milk loss related to SCC as a function of cow and operation related explanatory variables for a representative dairy cow. The largest losses occurred from increased cumulative test days with a SCC ≥100,000 cells/mL, with daily losses of $1.20/cow per day in the first month to $2.06/cow per day in mo 10. Results demonstrate the importance of including the duration of months above a threshold SCC when estimating milk yield losses. Cows with chronic mastitis, measured by increased consecutive test days with SCC ≥100,000 cells/mL, resulted in higher milk losses than cows with a new infection. This provides farm managers with a method to evaluate the trade-off between treatment and culling decisions as it relates to mastitis control and early detection. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. [Body condition and metabolic stability as the basis for high milk yield and undisturbed fertility in dairy cows--a contribution for deduction of reference values].

    PubMed

    Staufenbiel, R; Arndt, G; Schröder, U; Gelfert, C C

    2004-05-01

    The target of this study was to describe the interactions between body condition and various descriptors of yield and fertility. It was aimed to identify an optimal conditional range to be used in herd management which combines high milk yield with acceptable fertility traits and general health. For this purpose, backfat thickness was measured by ultrasound at 46111 dairy cows on 78 different farms and was subsequently related to production variables. Negative energy balance is getting more intense and prolonged with increasing milk yield. However a conditional nadir below 10 mm leads to decreased milk production. To reach a high production level without an increasing incidence of health disorders, conditional nadir should not decline below 13 mm backfat thickness on herd average. Lower value only lead to negligibly higher milk yield but cause a distinctively higher risk of fertility problems and culling. High herd yields do not have to be at expense of reproduction performance and can be achieved without extreme body condition losses. An efficient herd management can offset depression in fertility, which commonly is combined with increasing milk yield. A standard curve for backfat thickness throughout lactation is suggested to be used in dairy herd management.

  13. Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields.

    PubMed

    Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M; Clifton-Brown, John; Lewandowski, Iris

    2017-01-01

    In Europe, the perennial C 4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August-March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion.

  14. Site-Specific Management of Miscanthus Genotypes for Combustion and Anaerobic Digestion: A Comparison of Energy Yields

    PubMed Central

    Kiesel, Andreas; Nunn, Christopher; Iqbal, Yasir; Van der Weijde, Tim; Wagner, Moritz; Özgüven, Mensure; Tarakanov, Ivan; Kalinina, Olena; Trindade, Luisa M.; Clifton-Brown, John; Lewandowski, Iris

    2017-01-01

    In Europe, the perennial C4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August–March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25% and a late harvest to 45% conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required to maintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion. PMID:28367151

  15. [Effects of nitrogen application level on soil nitrate accumulation and ammonia volatilization in high-yielding wheat field].

    PubMed

    Wang, Dong; Yu, Zhenwen; Yu, Wenming; Shi, Yu; Zhou, Zhongxin

    2006-09-01

    The study showed that during the period from sowing to pre-wintering, the soil nitrate in high-yielding wheat field moved down to deeper layers, and accumulated in the layers below 140 cm. An application rate of 96-168 kg N x hm(-2) increased the nitrate content in 0-60 cm soil layer and the wheat grain yield and its protein content, and decreased the proportion of apparent N loss to applied N and the ammonia volatilization loss from basal nitrogen. Applying 240 kg N x hm(-2) promoted the downward movement of soil nitrate and its accumulation in deeper layers, increased the proportion of apparent N loss to applied N and the ammonia volatilization loss from basal nitrogen, had no significant effect on the protein content of wheat grain, but decreased the grain yield. The appropriate application rate of nitrogen on high-yielding wheat field was 132-204 kg N x hm(-2).

  16. Genetics, Physiological Mechanisms and Breeding of Flood-Tolerant Rice (Oryza sativa L.).

    PubMed

    Singh, Anuradha; Septiningsih, Endang M; Balyan, Harendra S; Singh, Nagendra K; Rai, Vandna

    2017-02-01

    Flooding of rice fields is a serious problem in the river basins of South and South-East Asia where about 15 Mha of lowland rice cultivation is regularly affected. Flooding creates hypoxic conditions resulting in poor germination and seedling establishment. Flash flooding, where rice plants are completely submerged for 10-15 d during their vegetative stage, causes huge losses. Water stagnation for weeks to months also leads to substantial yield losses when large parts of rice aerial tissues are inundated. The low-yielding traditional varieties and landraces of rice adapted to these flooding conditions have been replaced by flood-sensitive high-yielding rice varieties. The 'FR13A' rice variety and the Submergence 1A (SUB1A) gene were identified for flash flooding and subsequently introgressed to high-yielding rice varieties. The challenge is to find superior alleles of the SUB1A gene, or even new genes that may confer greater tolerance to submergence. Similarly, genes have been identified in tolerant landraces of rice for their ability to survive by rapid stem elongation (SNORKEL1 and SNORKEL2) during deep-water flooding, and for anaerobic germination ability (TPP7). Research on rice genotypes and novel genes that are tolerant to prolonged water stagnation is in progress. These studies will greatly assist in devising more efficient and precise molecular breeding strategies for developing climate-resilient high-yielding rice varieties for flood-prone regions. Here we review the state of our knowledge of flooding tolerance in rice and its application in varietal improvement. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. 7 CFR 1437.10 - Notice of loss, appraisal requirements, and application for payment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the final planting date, (2) For low yield claims and allowable value loss, the earlier of: (i) 15 calendar days after the damaging weather or adverse natural occurrence, or date loss of the crop or commodity becomes apparent for low yield claims; and (ii) 15 calendar days after the normal harvest date. (b...

  18. 7 CFR 1437.10 - Notice of loss, appraisal requirements, and application for payment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the final planting date, (2) For low yield claims and allowable value loss, the earlier of: (i) 15 calendar days after the damaging weather or adverse natural occurrence, or date loss of the crop or commodity becomes apparent for low yield claims; and (ii) 15 calendar days after the normal harvest date. (b...

  19. 7 CFR 1437.10 - Notice of loss, appraisal requirements, and application for payment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the final planting date, (2) For low yield claims and allowable value loss, the earlier of: (i) 15 calendar days after the damaging weather or adverse natural occurrence, or date loss of the crop or commodity becomes apparent for low yield claims; and (ii) 15 calendar days after the normal harvest date. (b...

  20. 7 CFR 1437.10 - Notice of loss, appraisal requirements, and application for payment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the final planting date, (2) For low yield claims and allowable value loss, the earlier of: (i) 15 calendar days after the damaging weather or adverse natural occurrence, or date loss of the crop or commodity becomes apparent for low yield claims; and (ii) 15 calendar days after the normal harvest date. (b...

  1. Yield Potential of Sugar Beet – Have We Hit the Ceiling?

    PubMed Central

    Hoffmann, Christa M.; Kenter, Christine

    2018-01-01

    The yield of sugar beet has continuously increased in the past decades. The question arises, whether this progress will continue in the future. A key factor for increasing yield potential of the crop is breeding progress. It was related to a shift in assimilate partitioning in the plant toward more storage carbohydrates (sucrose), whereas structural carbohydrates (leaves, cell wall compounds) unintendedly declined. The yield potential of sugar beet was estimated at 24 t sugar ha-1. For maximum yield, sufficient growth factors have to be available and the crop has to be able to fully utilize them. In sugar beet, limitations result from the lacking coincidence of maximum irradiation rates and full canopy cover, sink strength for carbon assimilation and high water demand, which cannot be met by rainfall alone. After harvest, sugar losses during storage occur. The paper discusses options for a further increase in yield potential, like autumn sowing of sugar beet, increasing sink strength and related constraints. It is prospected that yield increase by further widening the ratio of storage and structural carbohydrates will come to its natural limit as a certain cell wall stability is necessary. New challenges caused by climate change and by prolonged processing campaigns will occur. Thus breeding for improved pathogen resistance and storage properties will be even more important for successful sugar beet production than a further increase in yield potential itself. PMID:29599787

  2. Interference and economic threshold level of little seed canary grass in wheat under different sowing times.

    PubMed

    Hussain, Saddam; Khaliq, Abdul; Matloob, Amar; Fahad, Shah; Tanveer, Asif

    2015-01-01

    Little seed canary grass (LCG) is a pernicious weed of wheat crop causing enormous yield losses. Information on the interference and economic threshold (ET) level of LCG is of prime significance to rationalize the use of herbicide for its effective management in wheat fields. The present study was conducted to quantify interference and ET density of LCG in mid-sown (20 November) and late-sown (10 December) wheat. Experiment was triplicated in randomized split-plot design with sowing dates as the main plots and LCG densities (10, 20, 30, and 40 plants m(-2)) as the subplots. Plots with two natural infestations of weeds including and excluding LCG were maintained for comparing its interference in pure stands with designated densities. A season-long weed-free treatment was also run. Results indicated that composite stand of weeds, including LCG, and density of 40 LCG plants m(-2) were more competitive with wheat, especially when crop was sown late in season. Maximum weed dry biomass was attained by composite stand of weeds including LCG followed by 40 LCG plants m(-2) under both sowing dates. Significant variations in wheat growth and yield were observed under the influence of different LCG densities as well as sowing dates. Presence of 40 LCG plants m(-2) reduced wheat yield by 28 and 34% in mid- and late-sown wheat crop, respectively. These losses were much greater than those for infestation of all weeds, excluding LCG. Linear regression model was effective in simulating wheat yield losses over a wide range of LCG densities, and the regression equations showed good fit to observed data. The ET levels of LCG were 6-7 and 2.2-3.3 plants m(-2) in mid- and late-sown wheat crop, respectively. Herbicide should be applied in cases when LCG density exceeds these levels under respective sowing dates.

  3. Signum, a new fungicide for control of leaf diseases in outdoor vegetables.

    PubMed

    Callens, D; Sarrazyn, R; Evens, W

    2005-01-01

    During three years, the new fungicide Signum, containing 6.7% pyraclostrobine + 26.7 % boscalid and developed by BASF. has been evaluated in leek, carrots and cabbages in several outdoor field experiments under practical conditions and during one year in outdoor lettuce. In leek, Phytophthora porri is one of the major leaf diseases causing lesions on differ ent places on the leaves, resulting in at least extra labour costs for trimming or even worse sometimes resulting in complete crop loss. So far, crop protection consists of repeated applications of fungicides especially during autumn and winter. Pyraclostrobin + boscalid has been evaluated in comparison with the fungicides mancozeb, mancozeb + metalaxyl-M and azoxystrobin. The progress of the disease during the growth season is discussed. For all parameters evaluated, pyraclostrobin + boscalid gave comparable or even better results than reference products. Especially during 2003, a small drop of the activity of benalaxyl against P. porri has been observed after repeated applications. In carrots, Erisiphe heraclei and Alternaria dauci are both the most common leaf diseases causing yield and quality loss. During periods of very high pressure of A. dauci, pyraclostrobin + boscalid, applied in a three weeks interval, revealed a superior activity compared with triazole references or compared with azoxystrobin. Against E. heraclei, a good control but also a clear dose response activity have been observed with pyraclostrobin + boscalid. Yield gain was approximately 30 ton /ha compared wih untreated. In Brussels sprouts, good efficacy was obtained against Mycosphaerella spp., Albugo candida and Alternaria spp. In outdoor lettuce Botrytis cinerea and Sclerotinia sclerotiorum are the most important diseases causing crop damage and reducing the quality of the heads. Pyraclostrobin + boscalid was evaluated in comparison with the standard fungicide iprodione. The plant protection was better with the new fungicide pyraclostrobin + boscalid.

  4. Assessing the environmental impacts of soil compaction in Life Cycle Assessment.

    PubMed

    Stoessel, Franziska; Sonderegger, Thomas; Bayer, Peter; Hellweg, Stefanie

    2018-07-15

    Maintaining biotic capacity is of key importance with regard to global food and biomass provision. One reason for productivity loss is soil compaction. In this paper, we use a statistical empirical model to assess long-term yield losses through soil compaction in a regionalized manner, with global coverage and for different agricultural production systems. To facilitate the application of the model, we provide an extensive dataset including crop production data (with 81 crops and corresponding production systems), related machinery application, as well as regionalized soil texture and soil moisture data. Yield loss is modeled for different levels of soil depth (0-25cm, 25-40cm and >40cm depth). This is of particular relevance since compaction in topsoil is classified as reversible in the short term (approximately four years), while recovery of subsoil layers takes much longer. We derive characterization factors quantifying the future average annual yield loss as a fraction of the current yield for 100years and applicable in Life Cycle Assessment studies of agricultural production. The results show that crops requiring enhanced machinery inputs, such as potatoes, have a major influence on soil compaction and yield losses, while differences between mechanized production systems (organic and integrated production) are small. The spatial variations of soil moisture and clay content are reflected in the results showing global hotspot regions especially susceptible to soil compaction, e.g. the South of Brazil, the Caribbean Islands, Central Africa, and the Maharashtra district of India. The impacts of soil compaction can be substantial, with highest annual yield losses in the range of 0.5% (95% percentile) due to one year of potato production (cumulated over 100y this corresponds to a one-time loss of 50% of the present yield). These modeling results demonstrate the necessity for including soil compaction effects in Life Cycle Impact Assessment. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. A double mutation in exon 6 of the [beta]-hexosaminidase [alpha] subunit in a patient with the B1 variant of Tay-Sachs disease

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

    Ainsworth, P.J.; Coulter-Mackie, M.B.

    1992-10-01

    The B1 variant form of Tay-Sachs disease is enzymologically unique in that the causative mutation(s) appear to affect the active site in the [alpha] subunit of [beta]-hexosaminidase A without altering its ability to associate with the [beta] subunit. Most previously reported B1 variant mutations were found in exon 5 within codon 178. The coding sequence of the [alpha] subunit gene of a patient with the B1 variant form was examined with a combination of reverse transcription of mRNA to cDNA, PCR, and dideoxy sequencing. A double mutation in exon 6 has been identified: a G[sub 574][yields]C transversion causing a val[submore » 192][yields]leu change and a G[sub 598][yields] A transition resulting in a val[sub 200][yields]met alteration. The amplified cDNAs were otherwise normal throughout their sequence. The 574 and 598 alterations have been confirmed by amplification directly from genomic DNA from the patient and her mother. Transient-expression studies of the two exon 6 mutations (singly or together) in COS-1 cells show that the G[sub 574][yields]C change is sufficient to cause the loss of enzyme activity. The biochemical phenotype of the 574 alteration in transfection studies is consistent with that expected for a B1 variant mutation. As such, this mutation differs from previously reported B1 variant mutations, all of which occur in exon 5. 31 refs., 2 figs., 2 tabs.« less

  6. Estimation of rice yield affected by drought and relation between rice yield and TVDI

    NASA Astrophysics Data System (ADS)

    Hongo, C.; Tamura, E.; Sigit, G.

    2016-12-01

    Impact of climate change is not only seen on food production but also on food security and sustainable development of society. Adaptation to climate change is a pressing issue throughout the world to reduce the risks along with the plans and strategies for food security and sustainable development. As a key adaptation to the climate change, agricultural insurance is expected to play an important role in stabilizing agricultural production through compensating the losses caused by the climate change. As the adaptation, the Government of Indonesia has launched agricultural insurance program for damage of rice by drought, flood and pest and disease. The Government started a pilot project in 2013 and this year the pilot project has been extended to 22 provinces. Having the above as background, we conducted research on development of new damage assessment method for rice using remote sensing data which could be used for evaluation of damage ratio caused by drought in West Java, Indonesia. For assessment of the damage ratio, estimation of rice yield is a key. As the result of our study, rice yield affected by drought in dry season could be estimated at level of 1 % significance using SPOT 7 data taken in 2015, and the validation result was 0.8t/ha. Then, the decrease ratio in rice yield about each individual paddy field was calculated using data of the estimated result and the average yield of the past 10 years. In addition, TVDI (Temperature Vegetation Dryness Index) which was calculated from Landsat8 data in heading season indicated the dryness in low yield area. The result suggests that rice yield was affected by irrigation water shortage around heading season as a result of the decreased precipitation by El Nino. Through our study, it becomes clear that the utilization of remote sensing data can be promising for assessment of the damage ratio of rice production precisely, quickly and quantitatively, and also it can be incorporated into the insurance procedures.

  7. Coupling loss characteristics of runoff-sediment-adsorbed and dissolved nitrogen and phosphorus on bare loess slope.

    PubMed

    Wu, Lei; Qiao, Shanshan; Peng, Mengling; Ma, Xiaoyi

    2018-05-01

    Soil and nutrient loss is a common natural phenomenon but it exhibits unclear understanding especially on bare loess soil with variable rainfall intensity and slope gradient, which makes it difficult to design control measures for agricultural diffuse pollution. We employ 30 artificial simulated rainfalls (six rainfall intensities and five slope gradients) to quantify the coupling loss correlation of runoff-sediment-adsorbed and dissolved nitrogen and phosphorus on bare loess slope. Here, we show that effects of rainfall intensity on runoff yield was stronger than slope gradient with prolongation of rainfall duration, and the effect of slope gradient on runoff yield reduced gradually with increased rainfall intensity. But the magnitude of initial sediment yield increased significantly from an average value of 6.98 g at 5° to 36.08 g at 25° with increased slope gradient. The main factor of sediment yield would be changed alternately with the dual increase of slope gradient and rainfall intensity. Dissolved total nitrogen (TN) and dissolved total phosphorus (TP) concentrations both showed significant fluctuations with rainfall intensity and slope gradient, and dissolved TP concentration was far less than dissolved TN. Under the double influences of rainfall intensity and slope gradient, adsorbed TN concentration accounted for 7-82% of TN loss concentration with an average of 58.6% which was the main loss form of soil nitrogen, adsorbed TP concentration accounted for 91.8-98.7% of TP loss concentration with an average of 96.6% which was also the predominant loss pathway of soil phosphorus. Nitrate nitrogen (NO 3 - -N) accounted for 14.59-73.92% of dissolved TN loss, and ammonia nitrogen (NH 4 + -N) accounted for 1.48-18.03%. NO 3 - -N was the main loss pattern of TN in runoff. Correlation between dissolved TN, runoff yield, and rainfall intensity was obvious, and a significant correlation was also found between adsorbed TP, sediment yield, and slope gradient. Our results provide the underlying insights needed to guide the control of nitrogen and phosphorus loss on loess hills.

  8. Selection of assessment methods for evaluating banana weevil Cosmopolites sordidus (Coleoptera: Curculionidae) damage on highland cooking banana (Musa spp., genome group AAA-EA).

    PubMed

    Gold, C S; Ragama, P E; Coe, R; Rukazambuga, N D T M

    2005-04-01

    Cosmopolites sordidus (Germar) is an important pest on bananas and plantains. Population build-up is slow and damage becomes increasingly important in successive crop cycles (ratoons). Yield loss results from plant loss, mat disappearance and reduced bunch size. Damage assessment requires destructive sampling and is most often done on corms of recently harvested plants. A wide range of damage assessment methods exist and there are no agreed protocols. It is critical to know what types of damage best reflect C. sordidus pest status through their relationships with yield loss. Multiple damage assessment parameters (i.e. for the corm periphery, cortex and central cylinder) were employed in two yield loss trials and a cultivar-screening trial in Uganda. Damage to the central cylinder had a greater effect on plant size and yield loss than damage to the cortex or corm periphery. In some cases, a combined assessment of damage to the central cylinder and cortex showed a better relationship with yield loss than an assessment of the central cylinder alone. Correlation, logistic and linear regression analyses showed weak to modest correlations between damage to the corm periphery and damage to the central cylinder. Thus, damage to the corm periphery is not a strong predictor of the more important damage to the central cylinder. Therefore, C. sordidus damage assessment should target the central cylinder and cortex.

  9. Optical and adhesive properties of dust deposits on solar mirrors and their effects on specular reflectivity and electrodynamic cleaning for mitigating energy-yield loss

    NASA Astrophysics Data System (ADS)

    Mazumder, Malay; Yellowhair, Julius; Stark, Jeremy; Heiling, Calvin; Hudelson, John; Hao, Fang; Gibson, Hannah; Horenstein, Mark

    2014-10-01

    Large-scale solar plants are mostly installed in semi-arid and desert areas. In those areas, dust layer buildup on solar collectors becomes a major cause for energy yield loss. Development of transparent electrodynamic screens (EDS) and their applications for self-cleaning operation of solar mirrors are presented with a primary focus on the removal dust particles smaller than 30 µm in diameter while maintaining specular reflection efficiency < 90%. An EDS consists of thin rectangular array of parallel transparent conducting electrodes deposited on a transparent dielectric surface. The electrodes are insulated from each other and are embedded within a thin transparent dielectric film. The electrodes are activated using three-phase high-voltage pulses at low current (< 1 mA/m2 ). The three-phase electric field charges the deposited particles, lifts them form the substrate by electrostatic forces and propels the dust layer off of the collector's surface by a traveling wave. The cleaning process takes less than 2 minutes; needs energy less than 1 Wh/m2 without requiring any water or manual labor. The reflection efficiency can be restored > 95% of the original clean-mirror efficiency. We briefly present (1) loss of specular reflection efficiency as a function of particle size distribution of deposited dust, and (2) the effects of the electrode design and materials used for minimizing initial loss of specular reflectivity in producing EDS-integrated solar mirrors. Optimization of EDS by using a figure of merit defined by the ratio of dust removal efficiency to the initial loss of specular reflection efficiency is discussed.

  10. Fusarium Toxins in Cereals: Occurrence, Legislation, Factors Promoting the Appearance and Their Management.

    PubMed

    Ferrigo, Davide; Raiola, Alessandro; Causin, Roberto

    2016-05-13

    Fusarium diseases of small grain cereals and maize cause significant yield losses worldwide. Fusarium infections result in reduced grain yield and contamination with mycotoxins, some of which have a notable impact on human and animal health. Regulations on maximum limits have been established in various countries to protect consumers from the harmful effects of these mycotoxins. Several factors are involved in Fusarium disease and mycotoxin occurrence and among them environmental factors and the agronomic practices have been shown to deeply affect mycotoxin contamination in the field. In the present review particular emphasis will be placed on how environmental conditions and stress factors for the crops can affect Fusarium infection and mycotoxin production, with the aim to provide useful knowledge to develop strategies to prevent mycotoxin accumulation in cereals.

  11. Photosynthesis and yield reductions from wheat stem sawfly (Hymenoptera: Cephidae): interactions with wheat solidness, water stress, and phosphorus deficiency.

    PubMed

    Delaney, Kevin J; Weaver, David K; Peterson, Robert K D

    2010-04-01

    The impact of herbivory on plants is variable and influenced by several factors. The current study examined causes of variation in the impact of larval stem mining by the wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), on spring wheat, Triticum aestivum L. We performed greenhouse experiments over 2 yr to (1) study whether biotic (hollow versus solid stemmed host wheat) and abiotic (water, phosphorus stress) factors interact with C. cinctus stem mining to influence degree of mined stem physiological (photosynthesis) and yield (grain weight) reductions; and (2) determine whether whole plant yield compensatory responses occur to offset stem-mining reductions. Flag leaf photosynthetic reduction was not detected 16-20 d after infestation, but were detected at 40-42 d and doubled from water or phosphorus stresses. Main stem grain weight decreased from 10 to 25% from stem mining, largely due to reductions in grain size, with greater reductions under low phosphorus and/or water levels. Phosphorus-deficient plants without water stress were most susceptible to C. cinctus, more than doubling the grain weight reduction due to larval feeding relative to other water and phosphorus treatments. Two solid stemmed varieties with stem mining had less grain weight loss than a hollow stemmed variety, so greater internal mechanical resistance may reduce larval stem mining and plant yield reductions. Our results emphasize the importance of sufficient water and macronutrients for plants grown in regions impacted by C. cinctus. Also, solid stemmed varieties not only reduce wheat lodging from C. cinctus, they may reduce harvested grain losses from infested stems.

  12. Fungal degradation of wood lignins: Geochemical perspectives from CuO-derived phenolic dimers and monomers

    NASA Astrophysics Data System (ADS)

    Goñi, Miguel A.; Nelson, Bryan; Blanchette, Robert A.; Hedges, John I.

    1993-08-01

    The elemental compositions and yields of CuO-derived phenol dimers and monomers from woods degraded by different fungi under laboratory and natural conditions were compared to those from undegraded controls. In laboratory experiments, white-rot fungi caused pronounced mass losses, lowered the organic carbon content of the remnant woods, and decreased the absolute carbon-normalized yields of the major classes of lignin phenol dimers and monomers. White-rot decay induced large losses of some CuO reaction products, such as (β,1-diketone and α,l-monoketone dimers and syringyl monomers, and increased the absolute yields of individual acidic reaction products, such as dehydrodivanillic acid, vanillic acid, and 2-syringylsyringic acid. In contrast, the brown-rot fungus, Fomitopsis pinicola, was less efficient in decaying lignin, inducing lower absolute lignin phenol losses and, in some cases, increasing the organic carbon content of remnant woods. Several lignin constituents, mainly carboxyvanillyl monomers and α,2-methyl and α,5-monoketone dimers, were produced during brown-rot degradation. Similar diagenetic trends were also apparent in the five woods collected from the field, suggesting the differences between white- and brown-rot decay are still apparent after more extensive degradation in natural environments. The lignin compositions from a selected set of previously analyzed sedimentary mixtures were generally consistent with the diagenetic trends observed in both laboratory and field samples. In some cases, however, geochemical parameters such as elevated dimer/monomer and carboxyvanillyl/ vanillyl monomer ratios clearly distinguished certain sedimentary lignins. In these samples, other processes, such as extensive fungal decay, bacterial degradation, or a nonwoody vascular plant origin, could be important factors affecting lignin compositions.

  13. Genetic parameters of milk production traits in response to a short once-daily milking period in crossbred Holstein × Normande dairy cows.

    PubMed

    Charton, C; Guinard-Flament, J; Lefebvre, R; Barbey, S; Gallard, Y; Boichard, D; Larroque, H

    2018-03-01

    Despite its potential utility for predicting cows' milk yield responses to once-daily milking (ODM), the genetic basis of cow milk trait responses to ODM has been scarcely if ever described in the literature, especially for short ODM periods. This study set out to (1) estimate the genetic determinism of milk yield and composition during a 3-wk ODM period, (2) estimate the genetic determinism of milk yield responses (i.e., milk yield loss upon switching cows to ODM and milk yield recovery upon switching them back to twice-daily milking; TDM), and (3) seek predictors of milk yield responses to ODM, in particular using the first day of ODM. Our trial used 430 crossbred Holstein × Normande cows and comprised 3 successive periods: 1 wk of TDM (control), 3 wk of ODM, and 2 wk of TDM. Implementing ODM for 3 wk reduced milk yield by 27.5% on average, and after resuming TDM cows recovered on average 57% of the milk lost. Heritability estimates in the TDM control period and 3-wk ODM period were, respectively, 0.41 and 0.35 for milk yield, 0.66 and 0.61 for milk fat content, 0.60 and 0.80 for milk protein content, 0.66 and 0.36 for milk lactose content, and 0.20 and 0.15 for milk somatic cell score content. Milk yield and composition during 3-wk ODM and TDM periods were genetically close (within-trait genetic correlations between experimental periods all exceeding 0.80) but were genetically closer within the same milking frequency. Heritabilities of milk yield loss observed upon switching cows to ODM (0.39 and 0.34 for milk yield loss in kg/d and %, respectively) were moderate and similar to milk yield heritabilities. Milk yield recovery (kg/d) upon resuming TDM was a trait of high heritability (0.63). Because they are easy to measure, TDM milk yield and composition and milk yield responses on the first day of ODM were investigated as predictors of milk yield responses to a 3-wk ODM to easily detect animals that are well adapted to ODM. Twice-daily milking milk yield and composition were found to be partly genetically correlated with milk yield responses but not closely enough for practical application. With genetic correlations of 0.98 and 0.96 with 3-wk ODM milk yield losses (in kg/d and %, respectively), milk yield losses on the first day of ODM proved to be more accurate in predicting milk yield responses on longer term ODM than TDM milk yield. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  14. Economic analysis of revenue losses and control costs associated with the spotted wing drosophila, Drosophila suzukii (Matsumura), in the California raspberry industry.

    PubMed

    Farnsworth, Derek; Hamby, Kelly A; Bolda, Mark; Goodhue, Rachael E; Williams, Jeffrey C; Zalom, Frank G

    2017-06-01

    The spotted wing drosophila (SWD), Drosophila suzukii (Matsumura), is an invasive vinegar fly with a preference for infesting commercially viable berries and stone fruits. SWD infestations can reduce yields significantly, necessitating additional management activities. This analysis estimates economic losses in the California raspberry industry that have resulted from the SWD invasion. California raspberry producers experienced considerable revenue losses and management costs in the first years following SWD's invasion of North America. Conventional producers have since developed effective chemical management programs, virtually eliminating revenue losses due to SWD and reducing the cost of management to that of purchasing and applying insecticides more often. Organic raspberry producers, who do not have access to the same chemical controls, continue to confront substantial SWD-related revenue losses. These losses can be mitigated only by applying expensive insecticides registered for organic use and by performing labor-intensive field sanitation. SWD's invasion into North America has caused extensive crop losses to berry and cherry crops in California and elsewhere. Agricultural producers and researchers have responded quickly to this pest by developing management programs that significantly reduce revenue losses. Economic losses are expected to continue to fall as producers learn to manage SWD more efficiently and as new control tactics become available. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. Crop damage and livestock depredation by wildlife: a case study from Nanda Devi Biosphere Reserve, India.

    PubMed

    Rao, K S; Maikhuri, R K; Nautiyal, S; Saxena, K G

    2002-11-01

    The success of conserving biological resources in any Biosphere Reserve or protected area depends on the extent of support and positive attitudes and perceptions of local people have towards such establishments. Ignoring the dependence of the local people for their subsistence needs on resources of such areas leads to conflicts between protected area managers and the local inhabitants. Crop yield losses and livestock depredation were serious problems observed in most buffer zone villages of Nanda Devi Biosphere Reserve. In the present study 10 villages situated in the buffer zone of Nanada Devi Biosphere Reserve (1612 km2 area) in Chamoli district of Uttaranchal, India were studied during 1996-97 using a questionnaire survey of each household (419 = households; 2253 = total population in 1991; 273 ha = cultivated area). Estimates of crop yield losses were made using paired plots technique in four representative villages for each crop species. The magnitude of crop yield losses varied significantly with the distance of agricultural field from forest boundary. The total crop yield losses were high for wheat and potato in all the villages. The spatial distribution of total crop yield losses in any village indicated that they were highest in the area near to forest and least in the area near to village for all crops. Losses from areas near to forest contributed to more than 50% of total losses for each crop in all villages. However, in Lata, Peng and Tolma villages, the losses are high for kidney bean and chemmi (local variety of kidney bean) which varied between 18.5% to 30% of total losses in those villages. Potato alone represents 43.6% of total crop yield loss due to wildlife in Dronagiri village in monetary terms. Among the crops, the monetary value of yield losses are least for amaranth and highest for kidney bean. The projected total value of crop yield losses due to wildlife damage for buffer zone villages located in Garhwal Himalaya is about Rs. 538,620 (US$ 15,389). Besides food grains, horticultural crops i.e. apple, also suffered maximum damage. Major wildlife agents responsible for crop damage were wild boar, bear, porcupine, monkey, musk deer and partridge (chokor). Monkey and wild boar alone accounted for about 50% to 60% of total crop damage in the study villages. Goat and sheep are the major livestock killed by leopard. The total value of livestock losses at prevailing market rates is about Rs. 1,024,520 (US$ 29,272) in the study villages. Due to existing conservation policies and laxity in implementation of preventive measures, the problems for local inhabitants are increasing. Potential solutions discussed emphasize the need to undertake suitable and appropriate protective measures to minimize the crop losses. Change in cropping and crop composition, particularly cultivation of medicinal plants (high value low volume crops), were also suggested. Besides, fair and quick disbursement of compensation for crop loss and livestock killing need to be adopted. Local people of the buffer zone area already have a negative attitude towards park/reserve establishment due to socio-political changes inducing major economic losses and this attitude may lead to clashes and confrontations if proper ameliorative measures are not taken immediately.

  16. [Assessment on the yield loss risk of longan caused by cold damage in South China].

    PubMed

    Zhao, Jun-fang; Yu, Hui-kang

    2016-02-01

    Using daily climate variables gathered from 64 meteorological stations in South China from 1961 to 2012, recognized hazard indicators about disaster grades of cold damage for longan, and methods on agricultural meteorological disasters risk and simulation technology, the yield loss risks of longan caused by cold damage in South China during different developmental periods were assessed. The results showed that during the period of physiologic differentiation of flower bud, the disasters of longan affected by mild cold damage in South China were the most common, followed by severe cold damage and moderate cold damage. The hazards caused by cold damage under different grades varied. In particular, under mild cold damage, light disaster of longan was found in Fujian, followed by Guangdong and Hainan, and Guangxi was serious. Under moderate cold damage, light disaster of longan was found in Hainan, followed by Guangdong and Guangxi, and Fujian was serious. Under severe cold damage, light disaster of longan was found in Hainan, followed by Guangdong and Guangxi, Fujian was serious. During the period of morphologic differentiation of flower bud, the disasters of longan affected by mild cold damage in South China were the most common, followed by severe cold damage and moderate cold damage, while the disasters of longan under mild, moderate and severe cold damages within this period were similar. Specifically, light disasters of longan were all found in Hainan, followed by Guangdong, Guangxi and Fujian. During the period of dormancy, the disaster of longan affected by mild cold damage in South China was the most common, followed by severe cold damage and moderate cold damage. Under mild and severe cold damage, light disaster of longan was found in Fujian, followed by Guangdong and Hainan, and Guangxi was serious. However, under moderate cold damage, light disaster of longan was found in Hainan and Guangxi, followed by Guangdong, and Fujian was serious. At the same level of hazard, the largest risk indices of yield loss of longan during different developmental stages significantly differed. Under mild cold damage, serious disasters of longan were found in the period of physiologic differentiation of flower bud, followed by the period of morphologic differentiation of flower bud and the period of dormancy. However, under moderate and severe cold damage, serious disasters of longan were found in the period of physiologic differentiation of flower bud, followed by the period of dormancy and the period of morphologic differentiation of flower bud.

  17. Exploring the effects of nitrogen fertilization management alternatives on nitrate loss and crop yields in tile-drained fields in Illinois.

    PubMed

    Jeong, Hanseok; Bhattarai, Rabin

    2018-05-01

    It is vital to manage the excessive use of nitrogen (N) fertilizer in corn production, the single largest consumer of N fertilizer in the United States, in order to achieve more sustainable agroecosystems. This study comprehensively explored the effects of N fertilization alternatives on nitrate loss and crop yields using the Root Zone Water Quality Model (RZWQM) in tile-drained fields in central Illinois. The RZWQM was tested for the prediction of tile flow, nitrate loss, and crop yields using eight years (1993-2000) of observed data and showed satisfactory model performances from statistical and graphical evaluations. Our model simulations demonstrated the maximum return to nitrogen (MRTN) rate (193 kgha -1 ), a newly advised N recommendation by the Illinois Nutrient Loss Reduction Strategy (INLRS), can be further reduced. Nitrate loss was reduced by 10.3% and 29.8%, but corn yields decreased by 0.3% and 1.9% at 156 and 150 kgha -1 of N fertilizer rate in the study sites A and E, respectively. Although adjustment of N fertilization timing presented a further reduction in nitrate loss, there was no optimal timing to ensure nitrate loss reduction and corn productivity. For site A, 100% spring application was the most productive and 40% fall, 10% pre-plant, and 50% side dress application generated the lowest nitrate loss. For site E, the conventional N application timing was verified as the best practice in both corn production and nitrate loss reduction. Compared to surface broadcast placement, injected N fertilizer in spring increased corn yield, but may also escalate nitrate loss. This study presented the need of an adaptive N fertilizer management due to the heterogeneity in agricultural systems, and raised the importance of timing and placement of N fertilizer, as well as further reduction in fertilizer rate to devise a better in-field N management practice. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Assessment of crop yield losses in Punjab and Haryana using 2 years of continuous in situ ozone measurements

    NASA Astrophysics Data System (ADS)

    Sinha, B.; Singh Sangwan, K.; Maurya, Y.; Kumar, V.; Sarkar, C.; Chandra, B. P.; Sinha, V.

    2015-08-01

    In this study we use a high-quality data set of in situ ozone measurements at a suburban site called Mohali in the state of Punjab to estimate ozone-related crop yield losses for wheat, rice, cotton and maize for Punjab and the neighbouring state Haryana for the years 2011-2013. We intercompare crop yield loss estimates according to different exposure metrics, such as AOT40 (accumulated ozone exposure over a threshold of 40) and M7 (mean 7-hour ozone mixing ratio from 09:00 to 15:59), for the two major crop growing seasons of kharif (June-October) and rabi (November-April) and establish a new crop-yield-exposure relationship for southern Asian wheat, maize and rice cultivars. These are a factor of 2 more sensitive to ozone-induced crop yield losses compared to their European and American counterparts. Relative yield losses based on the AOT40 metrics ranged from 27 to 41 % for wheat, 21 to 26 % for rice, 3 to 5 % for maize and 47 to 58 % for cotton. Crop production losses for wheat amounted to 20.8 ± 10.4 million t in the fiscal year of 2012-2013 and 10.3 ± 4.7 million t in the fiscal year of 2013-2014 for Punjab and Haryana taken together. Crop production losses for rice totalled 5.4 ± 1.2 million t in the fiscal year of 2012-2013 and 3.2 ± 0.8 million t in the year 2013-2014 for Punjab and Haryana taken together. The Indian National Food Security Ordinance entitles ~ 820 million of India's poor to purchase about 60 kg of rice or wheat per person annually at subsidized rates. The scheme requires 27.6 Mt of wheat and 33.6 Mt of rice per year. The mitigation of ozone-related crop production losses in Punjab and Haryana alone could provide > 50 % of the wheat and ~ 10 % of the rice required for the scheme. The total economic cost losses in Punjab and Haryana amounted to USD 6.5 ± 2.2 billion in the fiscal year of 2012-2013 and USD 3.7 ± 1.2 billion in the fiscal year of 2013-2014. This economic loss estimate represents a very conservative lower limit based on the minimum support price of the crop, which is lower than the actual production costs. The upper limit for ozone-related crop yield losses in all of India currently amounts to 3.5-20 % of India's GDP. The mitigation of high surface ozone would require relatively little investment in comparison to the economic losses incurred presently. Therefore, ozone mitigation can yield massive benefits in terms of ensuring food security and boosting the economy. The co-benefits of ozone mitigation also include a decrease in the ozone-related mortality and morbidity and a reduction of the ozone-induced warming in the lower troposphere.

  19. Water deficit in field-grown Gossypium hirsutum primarily limits net photosynthesis by decreasing stomatal conductance, increasing photorespiration, and increasing the ratio of dark respiration to gross photosynthesis.

    PubMed

    Chastain, Daryl R; Snider, John L; Collins, Guy D; Perry, Calvin D; Whitaker, Jared; Byrd, Seth A

    2014-11-01

    Much effort has been expended to improve irrigation efficiency and drought tolerance of agronomic crops; however, a clear understanding of the physiological mechanisms that interact to decrease source strength and drive yield loss has not been attained. To elucidate the underlying mechanisms contributing to inhibition of net carbon assimilation under drought stress, three cultivars of Gossypium hirsutum were grown in the field under contrasting irrigation regimes during the 2012 and 2013 growing season near Camilla, Georgia, USA. Physiological measurements were conducted on three sample dates during each growing season (providing a broad range of plant water status) and included, predawn and midday leaf water potential (ΨPD and ΨMD), gross and net photosynthesis, dark respiration, photorespiration, and chlorophyll a fluorescence. End-of-season lint yield was also determined. ΨPD ranged from -0.31 to -0.95MPa, and ΨMD ranged from -1.02 to -2.67MPa, depending upon irrigation regime and sample date. G. hirsutum responded to water deficit by decreasing stomatal conductance, increasing photorespiration, and increasing the ratio of dark respiration to gross photosynthesis, thereby limiting PN and decreasing lint yield (lint yield declines observed during the 2012 growing season only). Conversely, even extreme water deficit, causing a 54% decline in PN, did not negatively affect actual quantum yield, maximum quantum yield, or photosynthetic electron transport. It is concluded that PN is primarily limited in drought-stressed G. hirsutum by decreased stomatal conductance, along with increases in respiratory and photorespiratory carbon losses, not inhibition or down-regulation of electron transport through photosystem II. It is further concluded that ΨPD is a reliable indicator of drought stress and the need for irrigation in field-grown cotton. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. Lead (Pb) Toxicity; Physio-Biochemical Mechanisms, Grain Yield, Quality, and Pb Distribution Proportions in Scented Rice.

    PubMed

    Ashraf, Umair; Kanu, Adam S; Deng, Quanquan; Mo, Zhaowen; Pan, Shenggang; Tian, Hua; Tang, Xiangru

    2017-01-01

    Lead (Pb) caused interruptions with normal plant metabolism, crop yield losses and quality issues are of great concern. This study assessed the physio-biochemical responses, yield and grain quality traits and Pb distribution proportions in three different fragrant rice cultivars i.e., Meixiangzhan-2, Xinagyaxiangzhan and Basmati-385. Plants were exposed to 400, 800, and 1,200 ppm of Pb while pots without Pb were taken as control (0 ppm). Our results showed that Pb toxicity significantly ( P < 0.05) reduced photosynthetic pigments (chlorophyll contents and carotenoids) and inducted oxidative stress with increased production of hydrogen peroxide (H 2 O 2 ), malanodialdehyde (MDA) and leaves leachates; while such effects were more apparent in Xinagyaxiangzhan than other two rice cultivars. Pb stress differentially affected the production protein, proline and soluble sugars; however the production rates were higher at heading stage (HS) than maturity stage (MS). Furthermore, Pb stress altered superoxide dismutase (SOD), peroxidases (POD), catalases (CAT) and ascorbate peroxidases (APX) activities and glutathione (GSH) and oxidized glutathione (GSSG) production in all rice cultivars at both HS and MS. All Pb levels reduced the yield and yield components of all rice cultivars; nonetheless such reductions were observed highest in Xinagyaxiangzhan (69.12%) than Meixiangzhan-2 (58.05%) and Basmati-385 (46.27%) and resulted in grain quality deterioration. Significant and positive correlations among rice yields with productive tillers/pot and grains per panicle while negative with sterility percentage were also observed. In addition, all rice cultivars readily taken up the Pb contents from soil to roots and transported upward in different proportions with maximum in roots followed by stemss, leaves, ears and grains. Higher proportions of Pb contents in above ground plant parts in Xinagyaxiangzhan possibly lead to maximum losses in this cultivar than other two cultivars; while less damage in Basmati-385 might be related to strong anti-oxidative defense system and lower proportions of Pb contents in its aerial parts.

  1. Slicing of Silicon into Sheet Material: Silicon Sheet Growth Development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project

    NASA Technical Reports Server (NTRS)

    Fleming, J. R.

    1979-01-01

    Testing of low cost low suspension power slurry vehicles is presented. Cutting oils are unlikely to work, but a mineral oil with additives should be workable. Two different abrasives were tested. A cheaper silicon carbide from Norton gave excellent results except for excessive kerf loss: the particles were too big. An abrasive treated for lubricity showed no lubricity improvement in mineral oil vehicle. The bounce fixture was tested for the first time under constant cut rate conditions (rather than constant force). Although the cut was not completed before the blades broke, the blade lifetime of thin (100 micrometer) blades was 120 times the lifetime without the fixture. The large prototype saw completed a successful run, producing 90% cutting yield (849 wafers) at 20 wafers/cm. Although inexperience with large numbers of wafers caused cleaning breakage to reduce this yield to 74%, the yield was high enough that the concept of the large saw is proven workable.

  2. U-Pb systematics of zircon and titanite from the Gardnos impact structure, Norway: Evidence for impact at 546 Ma?

    NASA Astrophysics Data System (ADS)

    Kalleson, E.; Corfu, F.; Dypvik, H.

    2009-05-01

    Zircon and titanite were investigated in impactites of the Gardnos structure, a crater formed in Sveconorwegian (ca. 1 Ga) crust, which was then overridden in the Devonian by Caledonian nappes. Observed deformation features in zircons are granular texture, planar microstructures, and likely the incorporation of organic carbon during impact causing black staining of the zircon grains. The grains were studied by scanning electron microscopy (SEM) and cathode luminescence (CL) and dated by U-Pb isotope dilution - thermo-ionization mass spectrometry (ID-TIMS). Zircon grains without impact related features have U-Pb data showing moderate discordance (5-13%) and indicating formation ages mostly in the range of 1600-1000 Ma, except detrital zircon ages as old as >2481 Ma, reflecting the diversity of target rocks in the area. Titanite with concordant ages of 995-999 Ma dates metamorphism during final juxtaposition of the Telemarkia on the Idefjorden terrane to the east. Zircon grains with demonstrated or presumed shock features yield highly discordant (14-40%) U-Pb data, with a majority of them plotting along an array with a lower intercept of about 340 Ma reflecting the influence of the Caledonian orogeny and recent Pb-loss. One zircon grain was totally reset at 379 Ma during late Caledonian metamorphism, which also caused local growth of new titanite. A specific group of zircon grains yields data with relatively high discordance for moderate U contents, and five of these analyses, including that of a grain with proven granular or aggregate texture, fit a discordia line with an upper intercept of 546 ± 5 Ma. These features are interpreted as indicating zircon break-down to an amorphous state during impact, with subsequent recrystallization into microcrystalline aggregates causing extensive to complete Pb loss. We further suggest that their crystallinity prevented Pb loss during the Caledonian orogeny, while the small subgrain size and increasing metamictisation allowed more recent disturbances. We thus interpret the 546 Ma age as the approximate time of impact.

  3. Interrelationships of somatic cell count, mastitis, and milk yield in a low somatic cell count herd.

    PubMed

    Deluyker, H A; Gay, J M; Weaver, L D

    1993-11-01

    In a high yielding low SCC herd, changes in milk yield associated with SCC and occurrence of clinical mastitis and differences in SCC with parity, clinical mastitis, and DIM were investigated. Milk yield data were obtained at every milking, and SCC was measured once every 48 h in 117 cows during the first 119 d postpartum. Effects of SCC and clinical mastitis on cumulative milk yield in the first 119 d postpartum were evaluated with least squares linear regression. Repeated measures ANOVA was used to detect changes in SCC. The SCC was highest at lactation onset, and cows with clinical mastitis had significantly higher SCC. During the 10 d prior to onset of clinical mastitis, SCC was higher in affected cows than in matched unaffected controls and surged just prior to diagnosis. During the 10-d period following a mastitis treatment, SCC differences between treated and control cows remained significant but became smaller with time and returned to the premastitis differences. Occurrence of clinical mastitis was associated with 5% milk yield loss. Cows with mean SCC > 245,000 cells/ml over the 119 d showed 6.2% yield loss compared with cows with SCC < or = 90,000 cells/ml. Cows with clinical mastitis had higher SCC prior to and following the end of treatment for mastitis than did controls. Clinical mastitis and SCC were associated with significant yield loss. Milk yield loss attributed to clinical mastitis was greater than that associated with elevated SCC (> 245,000 cells/ml) because a greater percentage of cows (26%) had clinical mastitis than elevated SCC (12.5%).

  4. Greenhouse gas emissions and stocks of soil carbon and nitrogen from a 20-year fertilised wheat-maize intercropping system: A model approach.

    PubMed

    Zhang, Xubo; Xu, Minggang; Liu, Jian; Sun, Nan; Wang, Boren; Wu, Lianhai

    2016-02-01

    Accurate modelling of agricultural management impacts on greenhouse gas emissions and the cycling of carbon and nitrogen is complicated due to interactions between various processes and the disturbance caused by field management. In this study, a process-based model, the Soil-Plant-Atmosphere Continuum System (SPACSYS), was used to simulate the effects of different fertilisation regimes on crop yields, the dynamics of soil organic carbon (SOC) and total nitrogen (SN) stocks from 1990 to 2010, and soil CO2 (2007-2010) and N2O (2007-2008) emissions based on a long-term fertilisation experiment with a winter-wheat (Triticum Aestivum L.) and summer-maize (Zea mays L.) intercropping system in Eutric Cambisol (FAO) soil in southern China. Three fertilisation treatments were 1) unfertilised (Control), 2) chemical nitrogen, phosphorus and potassium (NPK), and 3) NPK plus pig manure (NPKM). Statistical analyses indicated that the SPACSYS model can reasonably simulate the yields of wheat and maize, the evolution of SOC and SN stocks and soil CO2 and N2O emissions. The simulations showed that the NPKM treatment had the highest values of crop yields, SOC and SN stocks, and soil CO2 and N2O emissions were the lowest from the Control treatment. Furthermore, the simulated results showed that manure amendment along with chemical fertiliser applications led to both C (1017 ± 470 kg C ha(-1) yr(-1)) and N gains (91.7 ± 15.1 kg N ha(-1) yr(-1)) in the plant-soil system, while the Control treatment caused a slight loss in C and N. In conclusion, the SPACSYS model can accurately simulate the processes of C and N as affected by various fertilisation treatments in the red soil. Furthermore, application of chemical fertilisers plus manure could be a suitable management for ensuring crop yield and sustaining soil fertility in the red soil region, but the ratio of chemical fertilisers to manure should be optimized to reduce C and N losses to the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. An evaluation of benthic macroinvertebrate biomass methodology : Part 1. Laboratory analytical methods.

    PubMed

    Mason, W T; Lewis, P A; Weber, C I

    1983-03-01

    Evaluation of analytical methods employed for wet weight (live or preserved samples) of benthic macroinvertebrates reveals that centrifugation at 140 x gravity for one minute yields constant biomass estimates. Less relative centrifugal force increases chance of incomplete removal of body moisture and results in weighing error, while greater force may rupture fragile macroinvertebrates, such as mayflies. Duration of specimen exposure in ethanol, formalin, and formol (formaling-ethanol combinations) causes significant body weight loss with within 48 hr formalin and formol cause less body weight loss than ethanol. However, as all preservatives tested cause body weight loss, preservation time of samples collected for comparative purposes should be treated uniformly. Dry weight estimates of macroinvertebrates are not significantly affected by kind of preservative or duration of exposure. Constant dry weights are attained by oven drying at 103 °C at a minimum of four hours or vacuum oven drying (15 inches of mercury pressure) at 103 °C for a minimum of one hour. Although requiring more time in preparation than oven drying and inalterably changing specimen body shape, freeze drying (10 microns pressure, -55 °C, 24 hr) provides constant dry weights and is advantageous for long term sample storage by minimizing curatorial attention. Constant ash-free dry weights of macroinvertebrate samples are attained by igniting samples at 500-550 °C for a minimum of one hour with slow cooling to room temperature in desiccators before weighing.

  6. Responses of Nitrogen Utilization and Apparent Nitrogen Loss to Different Control Measures in the Wheat and Maize Rotation System

    PubMed Central

    Peng, Zhengping; Liu, Yanan; Li, Yingchun; Abawi, Yahya; Wang, Yanqun; Men, Mingxin; An-Vo, Duc-Anh

    2017-01-01

    Nitrogen (N) is an essential macronutrient for plant growth and excessive application rates can decrease crop yield and increase N loss into the environment. Field experiments were carried out to understand the effects of N fertilizers on N utilization, crop yield and net income in wheat and maize rotation system of the North China Plain (NCP). Compared to farmers’ N rate (FN), the yield of wheat and maize in reduction N rate by 21–24% based on FN (RN) was improved by 451 kg ha-1, N uptakes improved by 17 kg ha-1 and net income increased by 1671 CNY ha-1, while apparent N loss was reduced by 156 kg ha-1. The controlled-release fertilizer with a 20% reduction of RN (CRF80%), a 20% reduction of RN together with dicyandiamide (RN80%+DCD) and a 20% reduction of RN added with nano-carbon (RN80%+NC) all resulted in an improvement in crop yield and decreased the apparent N losses compared to RN. Contrasted with RN80%+NC, the total crop yield in RN80%+DCD improved by 1185 kg ha-1, N uptake enhanced by 9 kg ha-1 and net income increased by 3929 CNY ha-1, while apparent N loss was similar. Therefore, a 37–39% overall decrease in N rate compared to farmers plus the nitrification inhibitor, DCD, was effective N control measure that increased crop yields, enhanced N efficiencies, and improved economic benefits, while mitigating apparent N loss. There is considerable scope for improved N use effieincy in the intensive wheat -maize rotation of the NCP. PMID:28228772

  7. Greenland ice sheet mass balance: a review.

    PubMed

    Khan, Shfaqat A; Aschwanden, Andy; Bjørk, Anders A; Wahr, John; Kjeldsen, Kristian K; Kjær, Kurt H

    2015-04-01

    Over the past quarter of a century the Arctic has warmed more than any other region on Earth, causing a profound impact on the Greenland ice sheet (GrIS) and its contribution to the rise in global sea level. The loss of ice can be partitioned into processes related to surface mass balance and to ice discharge, which are forced by internal or external (atmospheric/oceanic/basal) fluctuations. Regardless of the measurement method, observations over the last two decades show an increase in ice loss rate, associated with speeding up of glaciers and enhanced melting. However, both ice discharge and melt-induced mass losses exhibit rapid short-term fluctuations that, when extrapolated into the future, could yield erroneous long-term trends. In this paper we review the GrIS mass loss over more than a century by combining satellite altimetry, airborne altimetry, interferometry, aerial photographs and gravimetry data sets together with modelling studies. We revisit the mass loss of different sectors and show that they manifest quite different sensitivities to atmospheric and oceanic forcing. In addition, we discuss recent progress in constructing coupled ice-ocean-atmosphere models required to project realistic future sea-level changes.

  8. Wash water solids removal system study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    During wash water purification, surfactants tend to precipitate and foul the RO membranes, causing water flux decline and loss of salt rejection. The use of 165 to 190 ppm ferric chloride and optionally 0.25 to 1.0 ppm polymeric flocculate precipitates 92 to 96 percent of the surfactant from an Olive Leaf Soap based wash water. Crossflow filtration and pressure filtration yield good soap rejection at high water flux rates. Post-treatment of the chemically pretreated and filtered wash water with activated charcoal removes the residual soap down to an undetectable level.

  9. Crop production and economic loss due to wind erosion in hot arid ecosystem of India

    NASA Astrophysics Data System (ADS)

    Santra, Priyabrata; Moharana, P. C.; Kumar, Mahesh; Soni, M. L.; Pandey, C. B.; Chaudhari, S. K.; Sikka, A. K.

    2017-10-01

    Wind erosion is a severe land degradation process in hot arid western India and affects the agricultural production system. It affects crop yield directly by damaging the crops through abrasion, burial, dust deposition etc. and indirectly by reducing soil fertility. In this study, an attempt was made to quantify the indirect impact of wind erosion process on crop production loss and associated economic loss in hot arid ecosystem of India. It has been observed that soil loss due to wind erosion varies from minimum 1.3 t ha-1 to maximum 83.3 t ha-1 as per the severity. Yield loss due to wind erosion was found maximum for groundnut (Arachis hypogea) (5-331 kg ha-1 yr-1), whereas minimum for moth bean (Vigna aconitifolia) (1-93 kg ha-1 yr-1). For pearl millet (Pennisetum glaucum), which covers a major portion of arable lands in western Rajasthan, the yield loss was found 3-195 kg ha-1 yr-1. Economic loss was found higher for groundnut and clusterbean (Cyamopsis tetragonoloba) than rest crops, which are about

  10. Flammability Parameters of Candles

    NASA Astrophysics Data System (ADS)

    Balog, Karol; Kobetičová, Hana; Štefko, Tomáš

    2017-06-01

    The paper deals with the assessment of selected fire safety characteristics of candles. Weight loss of a candle during the burning process, candle burning rate, soot index, heat release rate and yield of carbon oxides were determined. Soot index was determined according to EN 15426: 2007 - Candles - Specification for Sooting Behavior. All samples met the prescribed amount of produced soot. Weight loss, heat release rate and the yield of carbon oxides were determined for one selected sample. While yield of CO increased during the measurement, the yield of CO2 decreased by half in 40 minutes.

  11. Seasonal variations in rainfall-induced soil erosion from forest roads in a Mediterranean area

    NASA Astrophysics Data System (ADS)

    Jordán, Antonio; Zavala, Lorena M.; Gil, Juan

    2014-05-01

    1. INTRODUCTION Land use change and the development of rural and eco-tourist activities have contributed to a strong development of forest roads in Spain during recent decades. Most of forest roads cause significant hydrological and geomorphological impacts at different scales, altering the runoff-runon patterns, the direction and properties of runoff water, and subsurface water flow. Some of these effects are caused by the removal of native vegetation from backslopes (Martínez-Zavala et al., 2008), which contributes to increased soil erosion and sediment yield in areas where natural soil erosion risk is usually low (Jordán and Martínez-Zavala, 2008; Jordán-López et al., 2009). Rainfall intensity, soil moisture, slope and vegetation cover are key factors for erosion risk in forest roads (Jordán and Martínez-Zavala, 2008; Cao et al., 2013). 2. METHODS Sixty backslopes with plant cover varying between dense shrubs and bare soil were selected. Rainfall simulations (90 mm/h during 20 minutes) were performed in winter (December 2012 - January 2013) and summer (August - September 2013) to study the effect of rainstorms at the end and beginning of the rainy season. Surface runoff was collected to determine runoff rates and sediment yields. Plant cover, rock fragment cover and the area covered by biological crusts were determined at each plot. Slope was determined with a portable clinometer (all selected plots were in the range 41-76%). 3. RESULTS Although soil loss was increased in winter, when soil moisture is higher, small differences were observed at vegetation cover above 75%. Plant cover above 40% considerably reduced sediment yield and runoff flow. In contrast, differences triggered between different plots with decreasing vegetation cover. In bare areas, rock fragments and biological crusts (mosses, lichens, liverworts and fungi) caused great differences between bare areas both during summer and winter periods. REFERENCES Cao, L., Zhang, K., Dai, H., Liang, Y. 2013. Modeling interrill erosion on unpaved roads in the Loess Plateau of China, Land Degradation & Development. DOI: 10.1002/ldr.2253 Jordán, A., Martínez-Zavala, L. 2008. Soil loss and runoff rates on unpaved forest roads in southern Spain after simulated rainfall. Forest Ecology and Management 255, 913-919. DOI: 10.1016/j.foreco.2007.10.002. Jordán-López, A., Martínez-Zavala, L., Bellinfante, N. 2009. Impact of different parts of unpaved forest roads on runoff and sediment yield in a Mediterranean area. Science of the Total Environment 407, 937-944. DOI: 10.1016/j.scitotenv.2008.09.047. Martínez-Zavala, L., Jordán López, A., Bellinfante, N. 2008. Seasonal variability of runoff and soil loss on forest road backslopes under simulated rainfall. Catena 74, 73-79. DOI: 10.1016/j.catena.2008.03.006.

  12. Heat-induced phytohormone changes are associated with disrupted early reproductive development and reduced yield in rice

    PubMed Central

    Wu, Chao; Cui, Kehui; Wang, Wencheng; Li, Qian; Fahad, Shah; Hu, Qiuqian; Huang, Jianliang; Nie, Lixiao; Peng, Shaobing

    2016-01-01

    Heat stress causes morphological and physiological changes and reduces crop yield in rice (Oryza sativa). To investigate changes in phytohormones and their relationships with yield and other attributes under heat stress, four rice varieties (Nagina22, Huanghuazhan, Liangyoupeijiu, and Shanyou 63) were grown in pots and subjected to three high temperature treatments plus control in temperature-controlled greenhouses for 15 d during the early reproductive phase. Yield reductions in Nagina22, Huanghuazhan, and Liangyoupeijiu were attributed to reductions in spikelet fertility, spikelets per panicle, and grain weight. The adverse effects of high temperature were alleviated by application of exogenous 6-benzylaminopurine (6-BA) in the heat-susceptible Liangyoupeijiu. High temperature stress reduced active cytokinins, gibberellin A1 (GA1), and indole-3-acetic acid (IAA), but increased abscisic acid (ABA) and bound cytokinins in young panicles. Correlation analyses and application of exogenous 6-BA revealed that high temperature-induced cytokinin changes may regulate yield components by modulating the differentiation and degradation of branches and spikelets, panicle exsertion, pollen vigor, anther dehiscence, and grain size. Heat-tolerant Shanyou 63 displayed minor changes in phytohormones, panicle formation, and grain yield under high temperature compared with those of the other three varieties. These results suggest that phytohormone changes are closely associated with yield formation, and a small reduction or stability in phytohormone content is required to avoid large yield losses under heat stress. PMID:27713528

  13. Organic matter loss from cultivated peat soils in Sweden

    NASA Astrophysics Data System (ADS)

    Berglund, Örjan; Berglund, Kerstin

    2015-04-01

    The degradation of drained peat soils in agricultural use is an underestimated source of loss of organic matter. Oxidation (biological degradation) of agricultural peat soils causes a loss of organic matter (OM) of 11 - 22 t ha-1 y-1 causing a CO2 emission of 20 - 40 t ha-1 y-1. Together with the associated N2O emissions from mineralized N this totals in the EU to about 98.5 Mton CO2 eq per year. Peat soils are very prone to climate change and it is expected that at the end of this century these values are doubled. The degradation products pollute surface waters. Wind erosion of peat soils in arable agriculture can cause losses of 3 - 30 t ha-1 y-1 peat also causing air pollution (fine organic particles). Subsidence rates are 1 - 2 cm per year which leads to deteriorating drainage effect and make peat soils below sea or inland water levels prone to flooding. Flooding agricultural peat soils is in many cases not possible without high costs, high GHG emissions and severe water pollution. Moreover sometimes cultural and historic landscapes are lost and meadow birds areas are lost. In areas where the possibility to regulate the water table is limited the mitigation options are either to increase biomass production that can be used as bioenergy to substitute some fossil fuel, try to slow down the break-down of the peat by different amendments that inhibit microbial activity, or permanent flooding. The negative effects of wind erosion can be mitigated by reducing wind speed or different ways to protect the soil by crops or fiber sheets. In a newly started project in Sweden a typical peat soil with and without amendment of foundry sand is cropped with reed canary grass, tall fescue and timothy to investigate the yield and greenhouse gas emissions from the different crops and how the sand effect the trafficability and GHG emissions.

  14. Effects of fungal degradation on the CuO oxidation products of lignin: A controlled laboratory study

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

    Hedges, J.I.; Weliky, K.; Devol, A.H.

    1988-11-01

    Duplicate samples of birch wood were degraded for 0, 4, 8 and 12 weeks by the white-rot fungus, Phlebia tremellosus, and for 12 weeks by 6 other white-rot and brown-rot fungi. P. tremellosus caused progressive weight losses and increased the H/C and O/C of the remnant wood by preferentially degrading the lignin component of the middle lamellae. Total yields of syringyl phenols were decreased 1.5 times as fast as total vanillyl phenol yields. Within both phenol families, aldehyde precursors were degraded faster than precursors of the corresponding ketones, which were obtained in constant proportion to the total phenol yield. Althoughmore » two other white-rot fungi caused similar lignin compositional trends, a fourth white-rot species, Coriolus versicolor, simultaneously eroded all cell wall components and did not concentrate polysaccharides in the remnant wood. The brown-rot fungi also preferentially attacked syringyl structural units, but degraded all phenol precursors at a much slower rate than the white-rotters and did not produce excess vanillic acid. Degradation by P. tremellosus linearly increased the vanillic acid/vanillin ratio, (Ad/Al)v, of the remnant birch wood throughout the 12 week degradation study and exponentially decreased the absolute yields of total vanillyl phenols, total syringyl phenols and the syringyl/vanillyl phenol ratio, S/V. At the highest (Ad/Al)v of 0.50 total yields of syringyl and vanillyl phenols were decreased by 65% and 80%, respectively, with a resulting reduction of 40% in the original S/V. Many of the diagenetically related compositional trends that have been previously reported for lignins in natural environments can be explained by white-rot fungal degradation.« less

  15. Modulations of stratospheric ozone by volcanic eruptions

    NASA Technical Reports Server (NTRS)

    Blanchette, Christian; Mcconnell, John C.

    1994-01-01

    We have used a time series of aerosol surface based on the measurements of Hofmann to investigate the modulation of total column ozone caused by the perturbation to gas phase chemistry by the reaction N2O5(gas) + H2O(aero) yields 2HNO3(gas) on the surface of stratospheric aerosols. We have tested a range of values for its reaction probability, gamma = 0.02, 0.13, and 0.26 which we compared to unperturbed homogeneous chemistry. Our analysis spans a period from Jan. 1974 to Oct. 1994. The results suggest that if lower values of gamma are the norm then we would expect larger ozone losses for highly enhanced aerosol content that for larger values of gamma. The ozone layer is more sensitive to the magnitude of the reaction probability under background conditions than during volcanically active periods. For most conditions, the conversion of NO2 to HNO3 is saturated for reaction probability in the range of laboratory measurements, but is only absolutely saturated following major volcanic eruptions when the heterogeneous loss dominates the losses of N2O5. The ozone loss due to this heterogeneous reaction increases with the increasing chlorine load. Total ozone losses calculated are comparable to ozone losses reported from TOMS and Dobson data.

  16. Manganese-induced cadmium stress tolerance in rice seedlings: Coordinated action of antioxidant defense, glyoxalase system and nutrient homeostasis.

    PubMed

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    The accumulation of cadmium (Cd) alters different physiological and biochemical attributes that affect plant growth and yield. In our study, we investigated the regulatory role of supplemental manganese (Mn) on hydroponically grown rice (Oryza sativa L. cv. BRRI dhan29) seedlings under Cd-stress conditions. Exposure of 14-d-old seedlings to 0.3mM CdCl 2 for three days caused growth inhibition, chlorosis, nutrient imbalance, and higher Cd accumulation. Higher Cd uptake caused oxidative stress through lipid peroxidation, loss of plasma membrane integrity, and overproduction of reactive oxygen species (ROS) and methylglyoxal (MG). The exogenous application of 0.3mM MnSO 4 to Cd-treated seedlings partly recovered Cd-induced water loss, chlorosis, growth inhibition, and nutrient imbalance by reducing Cd uptake and its further translocation to the upper part of the plant. Supplemental Mn also reduced Cd-induced oxidative damage and lipid peroxidation by improved antioxidant defense and glyoxalase systems through enhancing ROS and MG detoxification, respectively. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  17. A mutation in the gamma actin 1 (ACTG1) gene causes autosomal dominant hearing loss (DFNA20/26)

    PubMed Central

    van Wijk, E; Krieger, E; Kemperman, M; De Leenheer, E M R; Huygen, P; Cremers, C; Cremers, F; Kremer, H

    2003-01-01

    Linkage analysis in a multigenerational family with autosomal dominant hearing loss yielded a chromosomal localisation of the underlying genetic defect in the DFNA20/26 locus at 17q25-qter. The 6-cM critical region harboured the γ-1-actin (ACTG1) gene, which was considered an attractive candidate gene because actins are important structural elements of the inner ear hair cells. In this study, a Thr278Ile mutation was identified in helix 9 of the modelled protein structure. The alteration of residue Thr278 is predicted to have a small but significant effect on the γ 1 actin structure owing to its close proximity to a methionine residue at position 313 in helix 11. Met313 has no space in the structure to move away. Moreover, the Thr278 residue is highly conserved throughout eukaryotic evolution. Using a known actin structure the mutation could be predicted to impair actin polymerisation. These findings strongly suggest that the Thr278Ile mutation in ACTG1 represents the first disease causing germline mutation in a cytoplasmic actin isoform. PMID:14684684

  18. Effects of climate and lifeform on dry matter yield (epsilon) from simulations using BIOME BGC. [ecosystem process model for vegetation biomass production using daily absorbed photosynthetically active radiation

    NASA Technical Reports Server (NTRS)

    Hunt, E. R., Jr.; Running, Steven W.

    1992-01-01

    An ecosystem process simulation model, BIOME-BGC, is used in a sensitivity analysis to determine the factors that may cause the dry matter yield (epsilon) and annual net primary production to vary for different ecosystems. At continental scales, epsilon is strongly correlated with annual precipitation. At a single location, year-to-year variation in net primary production (NPP) and epsilon is correlated with either annual precipitation or minimum air temperatures. Simulations indicate that forests have lower epsilon than grasslands. The most sensitive parameter affecting forest epsilon is the total amount of living woody biomass, which affects NPP by increasing carbon loss by maintenance respiration. A global map of woody biomass should significantly improve estimates of global NPP using remote sensing.

  19. Evaluation of late vegetative and reproductive stage soybeans for resistance to soybean aphid (Hemiptera: Aphididae).

    PubMed

    Prochaska, T J; Pierson, L M; Baldin, E L L; Hunt, T E; Heng-Moss, T M; Reese, J C

    2013-04-01

    The soybean aphid, Aphis glycines Matsumura, has become the most significant soybean [Glycine max (L.) Merrill] insect pest in the north central soybean production region of North America. The objectives of this research were to measure selected genotypes for resistance to the soybean aphid in the later vegetative and reproductive stages under field conditions, and confirm the presence of tolerance in KS4202. The results from 2007 to 2011 indicate that KS4202 can support aphid populations with minimal yield loss at levels where significant yield loss would be expected in most other genotypes. The common Nebraska cultivar, 'Asgrow 2703', appears to show signs of tolerance as well. None of the yield parameters were significantly different between the aphid infested and noninfested treatments. Based on our results, genotypes may compensate for aphid feeding in different ways. Asgrow 2703 appears to produce a similar number of seeds as its noninfested counterpart, although the seeds produced are slightly smaller. Field evaluation of tolerance in KS4202 indicated a yield loss of only 13% at 34,585-53,508 cumulative aphid-days, when 24-36% yield loss would have been expected.

  20. Major QTLs Control Resistance to Rice Hoja Blanca Virus and Its Vector Tagosodes orizicolus

    PubMed Central

    Romero, Luz E.; Lozano, Ivan; Garavito, Andrea; Carabali, Silvio J.; Triana, Monica; Villareal, Natalia; Reyes, Luis; Duque, Myriam C.; Martinez, César P.; Calvert, Lee; Lorieux, Mathias

    2013-01-01

    Rice hoja blanca (white leaf) disease can cause severe yield losses in rice in the Americas. The disease is caused by the rice hoja blanca virus (RHBV), which is transmitted by the planthopper vector Tagosodes orizicolus. Because classical breeding schemes for this disease rely on expensive, time-consuming screenings, there is a need for alternatives such as marker-aided selection. The varieties Fedearroz 2000 and Fedearroz 50, which are resistant to RHBV and to the feeding damage caused by T. orizicolus, were crossed with the susceptible line WC366 to produce segregating F2:3 populations. The F3 families were scored for their resistance level to RHBV and T. orizicolus. The F2:3 lines of both crosses were genotyped using microsatellite markers. One major QTL on the short arm of chromosome 4 was identified for resistance to RHBV in the two populations. Two major QTL on chromosomes 5 and 7 were identified for resistance to T. orizicolus in the Fd2000 × WC366 and Fd50 × WC366 crosses, respectively. This comparative study using two distinct rice populations allowed for a better understanding of how the resistance to RHBV and its vector are controlled genetically. Simple marker-aided breeding schemes based on QTL information can be designed to improve rice germplasm to reduce losses caused by this important disease. PMID:24240781

  1. Thresholds, injury, and loss relationships for thrips in Phleum pratense (Poales: Poaceae).

    PubMed

    Reisig, Dominic D; Godfrey, Larry D; Marcum, Daniel B

    2009-12-01

    Timothy (Phleum pratense L.) is an important forage crop in many Western U.S. states. Marketing of timothy hay is primarily based on esthetics, and green color is an important attribute. The objective of these studies was to determine a relationship between arthropod populations, yield, and esthetic injury in timothy. Economic injury levels (EILs) and economic thresholds were calculated based on these relationships. Thrips (Thripidae) numbers were manipulated with insecticides in small plot studies in 2006, 2007, and 2008, although tetranychid mite levels were incidentally flared by cyfluthrin in some experiments. Arthropod population densities were determined weekly, and yield and esthetic injury were measured at each harvest. Effects of arthropods on timothy were assessed using multilinear regression. Producers were also surveyed to relate economic loss from leaf color to the injury ratings for use in establishing EILs. Thrips population levels were significantly related to yield loss in only one of nine experiments. Thrips population levels were significantly related to injury once before the first annual harvest and twice before the second. Thrips were the most important pest in these experiments, and they were more often related to esthetic injury rather than yield loss. EILs and economic thresholds for thrips population levels were established using esthetic injury data. These results document the first example of a significant relationship between arthropod pest population levels and economic yield and quality losses in timothy.

  2. Quantification of ozone exposure- and stomatal uptake-yield response relationships for soybean in Northeast China.

    PubMed

    Zhang, Weiwei; Feng, Zhaozhong; Wang, Xiaoke; Liu, Xiaobing; Hu, Enzhu

    2017-12-01

    High ground-level O 3 is a new threat to agricultural production in Northeast China with the increasing ambient O 3 concentration. Little is known about its impacts on soybean production in this key agricultural region. Accumulated O 3 exposure-response and stomatal O 3 flux-response relationships were developed during two continuous growing seasons to evaluate O 3 -induced yield reduction of four typical soybean cultivars in Northeast China. Results showed that critical levels of AOT40 (accumulated hourly O 3 concentrations over a threshold of 40nmol·mol -1 ), SUM06 (sum of all hourly average O 3 concentrations over 0.06μmol·mol -1 ) and W126 (sum of O 3 concentrations weighted by a sigmoidal function) in relation to 5% reduction in relative seed yield were 4.2, 7.6 and 6.8μmol·mol -1 ·h, respectively. The effect of O 3 on plants was influenced by leaf position in canopy. An improved Jarvis stomatal conductance model including leaf (node) position fitted well with field measurements. The best linear relationship between stomatal O 3 flux and relative soybean yield was obtained when phytotoxic ozone dose was integrated over a threshold of 9.6nmol·m -2 ·s -1 (POD 9.6 ) to represent the detoxification capacity of soybean. POD 9.6 and the commonly used POD 6 in relation to 5% reduction in relative seed yield of soybean were 0.9mmol·m -2 and 1.8mmol·m -2 , respectively. O 3 concentrations above ~38nmol·mol -1 contributed to POD 9.6 and caused seed yield loss in soybean. Current annual yield loss of soybean at ambient O 3 was estimated to range between 23.4% and 30.2%. The O 3 dose-response relationships and corresponding thresholds obtained here will benefit regional O 3 risk assessment on soybean production in Northeast China. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. An Investigation of Widespread Ozone Damage to the Soybean Crop in the Upper Midwest Determined From Ground-Based and Satellite Measurements

    NASA Technical Reports Server (NTRS)

    Fishman, Jack; Creilson, John K.; Parker, Peter A.; Ainsworth, Elizabeth A.; Vining, G. Geoffrey; Szarka, John; Booker, Fitzgerald L.; Xu, Xiaojing

    2010-01-01

    Elevated concentrations of ground-level ozone (O3) are frequently measured over farmland regions in many parts of the world. While numerous experimental studies show that O3 can significantly decrease crop productivity, independent verifications of yield losses at current ambient O3 concentrations in rural locations are sparse. In this study, soybean crop yield data during a 5-year period over the Midwest of the United States were combined with ground and satellite O3 measurements to provide evidence that yield losses on the order of 10% could be estimated through the use of a multiple linear regression model. Yield loss trends based on both conventional ground-based instrumentation and satellite-derived tropospheric O3 measurements were statistically significant and were consistent with results obtained from open-top chamber experiments and an open-air experimental facility (SoyFACE, Soybean Free Air Concentration Enrichment) in central Illinois. Our analysis suggests that such losses are a relatively new phenomenon due to the increase in background tropospheric O3 levels over recent decades. Extrapolation of these findings supports previous studies that estimate the global economic loss to the farming community of more than $10 billion annually.

  4. Nitrogen rate strategies for reducing yield-scaled nitrous oxide emissions in maize

    NASA Astrophysics Data System (ADS)

    Zhao, Xu; Nafziger, Emerson D.; Pittelkow, Cameron M.

    2017-12-01

    Mitigating nitrogen (N) losses from agriculture without negatively impacting crop productivity is a pressing environmental and economic challenge. Reductions in N fertilizer rate are often highlighted as a solution, yet the degree to which crop yields and economic returns may be impacted at the field-level remains unclear, in part due to limited data availability. Farmers are risk averse and potential yield losses may limit the success of voluntary N loss mitigation protocols, thus understanding field-level yield tradeoffs is critical to inform policy development. Using a case study of soil N2O mitigation in the US Midwest, we conducted an ex-post assessment of two economic and two environmental N rate reduction strategies to identify promising practices for maintaining maize yields and economic returns while reducing N2O emissions per unit yield (i.e. yield-scaled emissions) compared to an assumed baseline N input level. Maize yield response data from 201 on-farm N rate experiments were combined with an empirical equation predicting N2O emissions as a function of N rate. Results indicate that the economic strategy aimed at maximizing returns to N (MRTN) led to moderate but consistent reductions in yield-scaled N2O emissions with small negative impacts on yield and slight increases in median returns. The economic optimum N rate strategy reduced yield-scaled N2O emissions in 75% of cases but increased them otherwise, challenging the assumption that this strategy will automatically reduce environmental impacts per unit production. Both environmental strategies, one designed to increase N recovery efficiency and one to balance N inputs with grain N removal, further reduced yield-scaled N2O emissions but were also associated with negative yield penalties and decreased returns. These results highlight the inherent tension between achieving agronomic and economic goals while reducing environmental impacts which is often overlooked in policy discussions. To enable the development of more scalable environmental N loss mitigation strategies, yield tradeoffs occurring at the critical point of adoption (i.e. the farm-level) should be considered.

  5. A comparative study of competitiveness between different genotypes of weedy rice (Oryza sativa) and cultivated rice.

    PubMed

    Dai, Lei; Dai, Weimin; Song, Xiaoling; Lu, Baorong; Qiang, Sheng

    2014-01-01

    Competition from weedy rice can cause serious yield losses to cultivated rice. However, key traits that facilitate competitiveness are still not well understood. To explore the mechanisms behind the strong growth and competitive ability, replacement series experiments were established with six genotypes of weedy rice from different regions and one cultivated rice cultivar. (1) Weedy rice from southern China had the greatest impact on growth and yield of cultivated rice throughout the entire growing season. Weedy rice from the northeast was very competitive during the early vegetative stage while the competitive effects of eastern weedy rice were more detrimental at later crop-growth stages. (2) As the proportion of weedy rice increased, plant height, tillers, above-ground biomass, and yield of cultivated rice significantly declined; the crop always being at disadvantage regardless of proportion. (3) Weedy biotypes with greater diversity as estimated by their Shannon indexes were more detrimental to the growth and yield of cultivated rice. Geographic origin (latitude) of weedy rice biotype, its mixture proportion under competition with the crop and its genetic diversity are determinant factors of the outcome of competition and the associated decline in the rice crop yield. © 2013 Society of Chemical Industry. © 2013 Society of Chemical Industry.

  6. Fewer not more leaves - Key to obtaining the needed jump in crop yield potential and water use efficiency

    NASA Astrophysics Data System (ADS)

    Srinivasan, V.; Kumar, P.; Long, S.

    2013-12-01

    Word food and feed supply needs to increase by 75% by 2050 to meet the increasing demands of our growing population. Soybean which is the world`s fourth most important crop in terms of total production at 250 million Mt/yr is a key protein source, and together with rice and wheat, are experiencing declining global yield increases year on year. At present rates of improvement, 2050 targets cannot be reached without new innovations. In this study we demonstrate an innovative approach that could provide a yield jump. While, natural selection favors individual plants to maximize leaf production to maximize light interception and shade competitors, the presence of this trait in domestic crops could be disadvantageous. In addition, rising CO2 causes increased leaf production further exacerbating the problem. Here, we show by mathematical model and field experiment that, a modern cultivar growing at the center of US soy cultivation produces too many leaves and reduction to an optimal level would increase yield. Our model results indicate that an LAI of 3.5 and 3.8 produces maximal rates of net canopy assimilation under ambient and elevated CO2 conditions respectively. However, observed peak LAI values are 6.9 and 7.5 under ambient and elevated CO2 conditions respectively. This results in a NPP loss of 30% and 20% under ambient and elevated CO2 conditions respectively. Furthermore, the optimal LAI results in a decreased transpiration of up to 30% thus increasing water use efficiency. We show that as LAI increases, the tradeoffs between diminishing day time gains in NPP, and increasing losses in respiration is responsible for this effect. By designing a more optimum canopy, we can increase NPP and this potentially translates to increased seed yield. To test this model result, we perform canopy manipulation experiments on soybean plants, where we artificially decrease LAI by periodically removing young and emerging leaves throughout the growing season (after pod onset), and measure the seed yield under ambient and elevated CO2 conditions. Our experimental results show that an LAI reduction of 0.5 results in an increased seed yield of 8.1% validating our model results. We propose that, by achieving a stronger LAI reduction, we can improve seed yields by up to 24% providing the much needed jump in yield to achieve future food security.

  7. Variable Rate Application of Nematicides on Cotton Fields: A Promising Site-Specific Management Strategy

    USDA-ARS?s Scientific Manuscript database

    Cotton (Gossypium hirsutum L.) lint yield losses associated with southern root-knot nematode [Meloidogyne incognita] (RKN) parasitism have increased during the last 20 years. The hypothesis that variable rate application of nematicides can reduce yield losses and reduce the risk for under- and over-...

  8. Peanut peg strength and associated pod yield and loss by cultivar

    USDA-ARS?s Scientific Manuscript database

    Peanut (Arachis hypogaea L.) peg strength and associated pod yield and digging loss were documented for nine cultivars and two breeding genotypes across three harvest dates at two Southwest Georgia locations during 2010 and 2011. Cultivars selected were Georgia Green, Georgia Greener, Georgia-02C, G...

  9. Inhibition of Orobanche crenata seed germination and radicle growth by allelochemicals identified in cereals.

    PubMed

    Fernández-Aparicio, Mónica; Cimmino, Alessio; Evidente, Antonio; Rubiales, Diego

    2013-10-16

    Orobanche crenata is a parasitic weed that causes severe yield losses in important grain and forage legume crops. Cereals have been reported to inhibit O. crenata parasitism when grown intercropped with susceptible legumes, but the responsible metabolites have not been identified. A number of metabolites have been reported in cereals that have allelopathic properties against weeds, pests, and pathogens. We tested the effect of several allelochemicals identified in cereals on O. crenata seed germination and radicle development. We found that 2-benzoxazolinone, its derivative 6-chloroacetyl-2-benzoxazolinone, and scopoletin significantly inhibited O. crenata seed germination. Benzoxazolinones, l-tryptophan, and coumalic acid caused the stronger inhibition of radicle growth. Also, other metabolites reduced radicle length, this inhibition being dose-dependent. Only scopoletin caused cell necrotic-like darkening in the young radicles. Prospects for their application to parasitic weed management are discussed.

  10. Pretreatment of CO oxidation catalysts

    NASA Technical Reports Server (NTRS)

    Vannorman, John D.

    1988-01-01

    CO oxidation catalysts with high activity in the range of 25 C to 100 C are important for long-life, closed-cycle operation of pulsed carbon dioxide 2 lasers. A reductive pretreatment with either CO or H sub 2 was shown to significantly enhance the activity of a commerically-available platinum on tin (IV) oxide (Pt/SnO2) catalyst relative to an oxidative or inert pretreatment or no pretreatment. Pretreatment at temperatures of 175 C and above caused an initial dip in observed CO or O sub 2 loss or CO sub 2 formation in a test gas mixture of 1 percent CO and 0.5 percent O sub 2 in a He gas matrix before a steady-state yield was obtained. This dip was found to be caused by dehydration of the surface of the catalyst and was readily eliminated by humidifying the catalyst or the test gas mixture. It was also found that too much moisture resulted in a lower overall yield of CO sub 2. Under similar conditions, it is hypothesized that the effect of the humidification is to increase the concentration of OH groups on the surface of the catalyst. The effect of having high concentration of CO sub 2 in the test gas mixture upon the loss of CO and O sub 2 as well as the effect of periods of relaxation of the catalyst under non-test gas conditions was studied. The purpose of these studies was to gain an insight into the mechanism of CO oxidation on this type of catalyst.

  11. Effect of Emamectin Benzoate on Root-Knot Nematodes and Tomato Yield

    PubMed Central

    Cheng, Xingkai; Liu, Xiumei; Wang, Hongyan; Ji, Xiaoxue; Wang, Kaiyun; Wei, Min; Qiao, Kang

    2015-01-01

    Southern root-knot nematode (Meloidogyne incognita) is an obligate, sedentary endoparasite of more than 3000 plant species, that causes heavy economic losses and limit the development of protected agriculture of China. As a biological pesticide, emamectin benzoate has effectively prevented lepidopteran pests; however, its efficacy to control M. incognita remains unknown. The purpose of the present study was to test soil application of emamectin benzoate for management of M. incognita in laboratory, greenhouse and field trials. Laboratory results showed that emamectin benzoate exhibited high toxicity to M. incognita, with LC50 and LC90 values 3.59 and 18.20 mg L-1, respectively. In greenhouse tests, emamectin benzoate soil application offered good efficacy against M. incognita while maintaining excellent plant growth. In field trials, emamectin benzoate provided control efficacy against M. incognita and resulted in increased tomato yields. Compared with the untreated control, there was a 36.5% to 81.3% yield increase obtained from all treatments and the highest yield was received from the highest rate of emamectin benzoate. The results confirmed that emamectin benzoate has enormous potential for the control of M. incognita in tomato production in China. PMID:26509680

  12. Effect of Emamectin Benzoate on Root-Knot Nematodes and Tomato Yield.

    PubMed

    Cheng, Xingkai; Liu, Xiumei; Wang, Hongyan; Ji, Xiaoxue; Wang, Kaiyun; Wei, Min; Qiao, Kang

    2015-01-01

    Southern root-knot nematode (Meloidogyne incognita) is an obligate, sedentary endoparasite of more than 3000 plant species, that causes heavy economic losses and limit the development of protected agriculture of China. As a biological pesticide, emamectin benzoate has effectively prevented lepidopteran pests; however, its efficacy to control M. incognita remains unknown. The purpose of the present study was to test soil application of emamectin benzoate for management of M. incognita in laboratory, greenhouse and field trials. Laboratory results showed that emamectin benzoate exhibited high toxicity to M. incognita, with LC50 and LC90 values 3.59 and 18.20 mg L(-1), respectively. In greenhouse tests, emamectin benzoate soil application offered good efficacy against M. incognita while maintaining excellent plant growth. In field trials, emamectin benzoate provided control efficacy against M. incognita and resulted in increased tomato yields. Compared with the untreated control, there was a 36.5% to 81.3% yield increase obtained from all treatments and the highest yield was received from the highest rate of emamectin benzoate. The results confirmed that emamectin benzoate has enormous potential for the control of M. incognita in tomato production in China.

  13. Incidence and factors associated with early pregnancy losses in Simmental dairy cows.

    PubMed

    Zobel, R; Tkalčić, S; Pipal, I; Buić, V

    2011-09-01

    It has been suggested that management system, milk yield, parity, body condition score and ambient temperature can significantly influence the rate of early pregnancy loss in dairy cattle. The objectives of this study were to establish the extent and patterns of early pregnancy loss from days 32 to 86 of gestation, and to check relationships between management system, milk yield, ambient temperature (quartile), body condition score, bull and parity on the early pregnancy loss rate for Simmental dairy cattle in Croatia. Animals were housed in two dairy farms with two different management systems (pasture based-group A, n=435 and intensive-group B, n=425) with a total of 151 heifers and 709 cows. Overall pregnancy losses were recorded in 67 (7.79%) animals, with late embryonic losses in 30 (44.77%) and early fetal losses in 37 (55.23%) animals (P>0.05). Early pregnancy losses were twofold higher in group B when compared to the group A (P<0.05). More than the half of pregnancy losses were recorded during the III quartile (P<0.05). There was no significant relationship between the paternal bull and pregnancy loss rate. Low body condition score (BCS 2-3) was associated with the highest, while BCS 3.25-4 showed the lowest pregnancy loss rate (P<0.05). The pregnancy loss rate increased in parallel with parity and milk yield increase. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Soil-pit Method for Distribution and Leaching Loss of Nitrogen in Winter Wheat’s Soil, Weishan Irrigation District

    NASA Astrophysics Data System (ADS)

    Zhao, Erni; Xu, Lirong; Wang, Rongzhen

    2018-01-01

    Unreasonable application of irrigation and fertilizer will cause the waste of water and nitrogen and environmental pollution. In this paper, a series of soil-pit experiments were carried out to study the distribution and leaching loss of nitrogen in winter wheat’s soil. The results showed that NO3 - concentration at 20-80cm depth mainly responded to fertilizer application at the beginning of field experiment, but the amount of irrigation became the dominant factor with the growth of winter wheat. It is noteworthy that the distribution of NO3 - was mainly affected by the amount of fertilizer applied at the depth of 120-160cm in the whole period of growth of winter wheat. The accumulation position of NH4 + was deepened as the amount of irrigation increased, however, the maximum aggregation depth of ammonium nitrogen was no more than 80cm owing to its poor migration. It can be concluded that the influence of irrigation amount on the concentration of NH4 + in soil solution was more obvious than that of fertilizer. Compared with fertilizer, the amount of irrigation played a leading role in the utilization ratio of nitrogen and the yield of winter wheat. In summary, the best water and fertilizer treatment occurred in No.3 soil-pit, which meant that the middle amount of water and fertilizer could get higher wheat yield and less nitrogen leaching losses in the study area.

  15. 7 CFR 760.611 - Qualifying losses, eligible causes and types of loss.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... final planting date; (4) The cause of loss was due to water contained or released by any governmental... containment or release of the water; (5) The cause of loss was due to conditions or events occurring outside...) Losses caused by a failure of power supply or brownout as defined in § 760.602; (2) Losses caused by the...

  16. 7 CFR 760.611 - Qualifying losses, eligible causes and types of loss.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., where the honey production by colonies or bees was diminished, are not a qualifying loss: (1) Losses... the honey operation; (2) Losses caused by improper storage of honey; (3) Losses caused by bee feeding... bees by the participant or any other legal entity or person; (7) Losses caused by disease or pest...

  17. 7 CFR 760.611 - Qualifying losses, eligible causes and types of loss.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., where the honey production by colonies or bees was diminished, are not a qualifying loss: (1) Losses... the honey operation; (2) Losses caused by improper storage of honey; (3) Losses caused by bee feeding... bees by the participant or any other legal entity or person; (7) Losses caused by disease or pest...

  18. 7 CFR 760.611 - Qualifying losses, eligible causes and types of loss.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., where the honey production by colonies or bees was diminished, are not a qualifying loss: (1) Losses... the honey operation; (2) Losses caused by improper storage of honey; (3) Losses caused by bee feeding... bees by the participant or any other legal entity or person; (7) Losses caused by disease or pest...

  19. 7 CFR 760.611 - Qualifying losses, eligible causes and types of loss.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., where the honey production by colonies or bees was diminished, are not a qualifying loss: (1) Losses... the honey operation; (2) Losses caused by improper storage of honey; (3) Losses caused by bee feeding... bees by the participant or any other legal entity or person; (7) Losses caused by disease or pest...

  20. A modified indirect mathematical model for evaluation of ethanol production efficiency in industrial-scale continuous fermentation processes.

    PubMed

    Canseco Grellet, M A; Castagnaro, A; Dantur, K I; De Boeck, G; Ahmed, P M; Cárdenas, G J; Welin, B; Ruiz, R M

    2016-10-01

    To calculate fermentation efficiency in a continuous ethanol production process, we aimed to develop a robust mathematical method based on the analysis of metabolic by-product formation. This method is in contrast to the traditional way of calculating ethanol fermentation efficiency, where the ratio between the ethanol produced and the sugar consumed is expressed as a percentage of the theoretical conversion yield. Comparison between the two methods, at industrial scale and in sensitivity studies, showed that the indirect method was more robust and gave slightly higher fermentation efficiency values, although fermentation efficiency of the industrial process was found to be low (~75%). The traditional calculation method is simpler than the indirect method as it only requires a few chemical determinations in samples collected. However, a minor error in any measured parameter will have an important impact on the calculated efficiency. In contrast, the indirect method of calculation requires a greater number of determinations but is much more robust since an error in any parameter will only have a minor effect on the fermentation efficiency value. The application of the indirect calculation methodology in order to evaluate the real situation of the process and to reach an optimum fermentation yield for an industrial-scale ethanol production is recommended. Once a high fermentation yield has been reached the traditional method should be used to maintain the control of the process. Upon detection of lower yields in an optimized process the indirect method should be employed as it permits a more accurate diagnosis of causes of yield losses in order to correct the problem rapidly. The low fermentation efficiency obtained in this study shows an urgent need for industrial process optimization where the indirect calculation methodology will be an important tool to determine process losses. © 2016 The Society for Applied Microbiology.

  1. Assessing disease stress and modeling yield losses in alfalfa

    NASA Astrophysics Data System (ADS)

    Guan, Jie

    Alfalfa is the most important forage crop in the U.S. and worldwide. Fungal foliar diseases are believed to cause significant yield losses in alfalfa, yet, little quantitative information exists regarding the amount of crop loss. Different fungicides and application frequencies were used as tools to generate a range of foliar disease intensities in Ames and Nashua, IA. Visual disease assessments (disease incidence, disease severity, and percentage defoliation) were obtained weekly for each alfalfa growth cycle (two to three growing cycles per season). Remote sensing assessments were performed using a hand-held, multispectral radiometer to measure the amount and quality of sunlight reflected from alfalfa canopies. Factors such as incident radiation, sun angle, sensor height, and leaf wetness were all found to significantly affect the percentage reflectance of sunlight reflected from alfalfa canopies. The precision of visual and remote sensing assessment methods was quantified. Precision was defined as the intra-rater repeatability and inter-rater reliability of assessment methods. F-tests, slopes, intercepts, and coefficients of determination (R2) were used to compare assessment methods for precision. Results showed that among the three visual disease assessment methods (disease incidence, disease severity, and percentage defoliation), percentage defoliation had the highest intra-rater repeatability and inter-rater reliability. Remote sensing assessment method had better precision than the percentage defoliation assessment method based upon higher intra-rater repeatability and inter-rater reliability. Significant linear relationships between canopy reflectance (810 nm), percentage defoliation and yield were detected using linear regression and percentage reflectance (810 nm) assessments were found to have a stronger relationship with yield than percentage defoliation assessments. There were also significant linear relationships between percentage defoliation, dry weight, percentage reflectance (810 nm), and green leaf area index (GLAI). Percentage reflectance (810 nm) assessments had a stronger relationship with dry weight and green leaf area index than percentage defoliation assessments. Our research conclusively demonstrates that percentage reflectance measurements can be used to nondestructively assess green leaf area index which is a direct measure of plant health and an indirect measure of productivity. This research conclusively demonstrates that remote sensing is superior to visual assessment method to assess alfalfa stress and to model yield and GLAI in the alfalfa foliar disease pathosystem.

  2. 1-Ethynylpyrene, a suicide inhibitor of cytochrome P-450 dependent benzo(a)pyrene hydroxylase activity in liver microsomes

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

    Gan, L.S.L.; Acebo, A.L.; Alworth, W.L.

    The preparation of 1-ethynylpyrene (EP) by incubation of EP with liver microsomes in the presence of NADPH yields fluorescent products briefly. Addition of microsomes restores the original rate. The metabolism of EP is initially more rapid in microsomes from 5,6-benzoflavone- (BF) pretreated rats than in those from phenobarbital (PB) pretreated rats or controls. Ep inhibits the hydroxylation of benzo(a)pyrene (BP) by liver microsomes. Ep more effectively inhibits the oxidation of BP in liver microsomes from BF rats than from PB rats or from controls. The inhibition of BP hydroxylation activity due to EP is dependent upon NADPH and is apparentlymore » irreversible. Kinetic analyses show that the inhibition of BP hydroxylation is due to loss of the activity by a process that is first order in EP and that reaches a limiting value at infinite EP concentrations. A self-catalyzed inhibition of the cytochrome P-450 dependent BP hydroxylation may occur in the presence of EP. Incubation with EP under conditions that result in loss of BP hydroxylase activity in microsomes from BF rats and 66% of the activity from PB rats causes the loss of 6 and 12% of the cytochrome P-450, respectively. Thus the loss of P-450 content is an insensitive measure of the effect of this inhibitor upon this cytochrome P-450 dependent enzyme activity. Selectivity of the loss of P-450 due to the incubation of the different microsomal preparations with EP is observed to be different than the selectivity for loss of BP hydroxylase activity. It is proposed that the inhibition of cytochrome P-450 dependent enzymes by alkynes need not involve heme alkylation and a resulting loss of P-450 content. In vivo EP does not cause a significant change in the cytochrome P-450 content in the microsomes isolated, or result in the change in BP hydroxylation.« less

  3. Identification of proteins of altered abundance in oil palm infected with Ganoderma boninense.

    PubMed

    Al-Obaidi, Jameel R; Mohd-Yusuf, Yusmin; Razali, Nurhanani; Jayapalan, Jaime Jacqueline; Tey, Chin-Chong; Md-Noh, Normahnani; Junit, Sarni Mat; Othman, Rofina Yasmin; Hashim, Onn Haji

    2014-03-24

    Basal stem rot is a common disease that affects oil palm, causing loss of yield and finally killing the trees. The disease, caused by fungus Ganoderma boninense, devastates thousands of hectares of oil palm plantings in Southeast Asia every year. In the present study, root proteins of healthy oil palm seedlings, and those infected with G. boninense, were analyzed by 2-dimensional gel electrophoresis (2-DE). When the 2-DE profiles were analyzed for proteins, which exhibit consistent significant change of abundance upon infection with G. boninense, 21 passed our screening criteria. Subsequent analyses by mass spectrometry and database search identified caffeoyl-CoA O-methyltransferase, caffeic acid O-methyltransferase, enolase, fructokinase, cysteine synthase, malate dehydrogenase, and ATP synthase as among proteins of which abundances were markedly altered.

  4. Identification of Proteins of Altered Abundance in Oil Palm Infected with Ganoderma boninense

    PubMed Central

    Al-Obaidi, Jameel R.; Mohd-Yusuf, Yusmin; Razali, Nurhanani; Jayapalan, Jaime Jacqueline; Tey, Chin-Chong; Md-Noh, Normahnani; Junit, Sarni Mat; Othman, Rofina Yasmin; Hashim, Onn Haji

    2014-01-01

    Basal stem rot is a common disease that affects oil palm, causing loss of yield and finally killing the trees. The disease, caused by fungus Ganoderma boninense, devastates thousands of hectares of oil palm plantings in Southeast Asia every year. In the present study, root proteins of healthy oil palm seedlings, and those infected with G. boninense, were analyzed by 2-dimensional gel electrophoresis (2-DE). When the 2-DE profiles were analyzed for proteins, which exhibit consistent significant change of abundance upon infection with G. boninense, 21 passed our screening criteria. Subsequent analyses by mass spectrometry and database search identified caffeoyl-CoA O-methyltransferase, caffeic acid O-methyltransferase, enolase, fructokinase, cysteine synthase, malate dehydrogenase, and ATP synthase as among proteins of which abundances were markedly altered. PMID:24663087

  5. Infantile cobalamin deficiency with cerebral lactate accumulation and sustained choline depletion.

    PubMed

    Horstmann, M; Neumaier-Probst, E; Lukacs, Z; Steinfeld, R; Ullrich, K; Kohlschütter, A

    2003-06-01

    A remarkable, intermittent sudden-onset vigilance and movement disorder in an exclusively breast-fed infant is reported, which was caused by cobalamin depletion due to maternal vitamin B12 malabsorption. The lack of cobalamin caused a severe encephalopathy in the infant, whose brain displayed a striking loss of volume and a delay of myelination. Proton magnetic resonance spectroscopy revealed an accumulation of lactate in the gray and white matter of the brain and a sustained depletion of choline-containing compounds in the white matter, reflecting a reversible disturbance of oxidative energy metabolism in brain cells and a long-lasting hypomyelination disorder. The clinical picture in conjunction with MRI and spectroscopic data of this case study yields more insight into the functions of cobalamin in the cerebral metabolism.

  6. Effects of halving pesticide use on wheat production

    PubMed Central

    Hossard, L.; Philibert, A.; Bertrand, M.; Colnenne-David, C.; Debaeke, P.; Munier-Jolain, N.; Jeuffroy, M. H.; Richard, G.; Makowski, D.

    2014-01-01

    Pesticides pose serious threats to both human health and the environment. In Europe, farmers are encouraged to reduce their use, and in France a recent environmental policy fixed a target of halving the pesticide use by 2018. Organic and integrated cropping systems have been proposed as possible solutions for reducing pesticide use, but the effect of reducing pesticide use on crop yield remains unclear. Here we use a set of cropping system experiments to quantify the yield losses resulting from a reduction of pesticide use for winter wheat in France. Our estimated yield losses resulting from a 50% reduction in pesticide use ranged from 5 to 13% of the yield obtained with the current pesticide use. At the scale of the whole country, these losses would decrease the French wheat production by about 2 to 3 millions of tons, which represent about 15% of the French wheat export. PMID:24651597

  7. Effects of halving pesticide use on wheat production

    NASA Astrophysics Data System (ADS)

    Hossard, L.; Philibert, A.; Bertrand, M.; Colnenne-David, C.; Debaeke, P.; Munier-Jolain, N.; Jeuffroy, M. H.; Richard, G.; Makowski, D.

    2014-03-01

    Pesticides pose serious threats to both human health and the environment. In Europe, farmers are encouraged to reduce their use, and in France a recent environmental policy fixed a target of halving the pesticide use by 2018. Organic and integrated cropping systems have been proposed as possible solutions for reducing pesticide use, but the effect of reducing pesticide use on crop yield remains unclear. Here we use a set of cropping system experiments to quantify the yield losses resulting from a reduction of pesticide use for winter wheat in France. Our estimated yield losses resulting from a 50% reduction in pesticide use ranged from 5 to 13% of the yield obtained with the current pesticide use. At the scale of the whole country, these losses would decrease the French wheat production by about 2 to 3 millions of tons, which represent about 15% of the French wheat export.

  8. Effects of halving pesticide use on wheat production.

    PubMed

    Hossard, L; Philibert, A; Bertrand, M; Colnenne-David, C; Debaeke, P; Munier-Jolain, N; Jeuffroy, M H; Richard, G; Makowski, D

    2014-03-20

    Pesticides pose serious threats to both human health and the environment. In Europe, farmers are encouraged to reduce their use, and in France a recent environmental policy fixed a target of halving the pesticide use by 2018. Organic and integrated cropping systems have been proposed as possible solutions for reducing pesticide use, but the effect of reducing pesticide use on crop yield remains unclear. Here we use a set of cropping system experiments to quantify the yield losses resulting from a reduction of pesticide use for winter wheat in France. Our estimated yield losses resulting from a 50% reduction in pesticide use ranged from 5 to 13% of the yield obtained with the current pesticide use. At the scale of the whole country, these losses would decrease the French wheat production by about 2 to 3 millions of tons, which represent about 15% of the French wheat export.

  9. Rice yield in response to climate trends and drought index in the Mun River Basin, Thailand.

    PubMed

    Prabnakorn, Saowanit; Maskey, Shreedhar; Suryadi, F X; de Fraiture, Charlotte

    2018-04-15

    Rice yields in Thailand are among the lowest in Asia. In northeast Thailand where about 90% of rice cultivation is rain-fed, climate variability and change affect rice yields. Understanding climate characteristics and their impacts on the rice yield is important for establishing proper adaptation and mitigation measures to enhance productivity. In this paper, we investigate climatic conditions of the past 30years (1984-2013) and assess the impacts of the recent climate trends on rice yields in the Mun River Basin in northeast Thailand. We also analyze the relationship between rice yield and a drought indicator (Standardized Precipitation and Evapotranspiration Index, SPEI), and the impact of SPEI trends on the yield. Our results indicate that the total yield losses due to past climate trends are rather low, in the range of <50kg/ha per decade (3% of actual average yields). In general, increasing trends in minimum and maximum temperatures lead to modest yield losses. In contrast, precipitation and SPEI-1, i.e. SPEI based on one monthly data, show positive correlations with yields in all months, except in the wettest month (September). If increasing trends of temperatures during the growing season persist, a likely climate change scenario, there is high possibility that the yield losses will become more serious in future. In this paper, we show that the drought index SPEI-1 detects soil moisture deficiency and crop stress in rice better than precipitation or precipitation based indicators. Further, our results emphasize the importance of spatial and temporal resolutions in detecting climate trends and impacts on yields. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Quality of white cabbage yield and potential risk of ground water nitrogen pollution, as affected by nitrogen fertilisation and irrigation practices.

    PubMed

    Maršić, Nina Kacjan; Sturm, Martina; Zupanc, Vesna; Lojen, Sonja; Pintar, Marina

    2012-01-15

    The effect of different fertilisation (broadcast solid NPK application and fertigation with water-soluble fertiliser) and irrigation practices (sprinkler and drip irrigation) on yield, the nitrate content in cabbage (Brassica oleracea var. capitata L.) and the cabbage N uptake was detected, in order to assess the potential risk for N losses, by cultivation on sandy-loam soil. The N rate applied on the plots was 200 kg N ha(-1). The highest yield (93 t ha(-1)) and nitrate content (1256 mg kg(-1) DW) were found with treatments using broadcast fertilisation and sprinkler irrigation. On those plots the negative N balance (-30 kg N ha(-1)) was recorded, which comes mainly from the highest crop N uptake (234 kg N ha(-1)) indicating the lowest potential for N losses. In terms of yield quality and the potential risk for N losses, broadcast fertilisation combined with sprinkler irrigation proved to be the most effective combination among the tested practices under the given experimental conditions. The importance of adequate irrigation is also evident, namely in plots on which 50% drip irrigation was applied, the lowest yield was detected and according to the positive N balance, a higher potential for N losses is expected. Copyright © 2011 Society of Chemical Industry.

  11. Effects of air pollutants on Los Angeles Basin citrus

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

    Thompson, C.R.; Taylor, O.C.; Richards, B.L.

    1970-03-01

    Commercially producing lemon and navel orange trees were enclosed in plastic covered greenhouses and were given various fractions of the air pollutants occurring in the Los Angeles Basin. In some treatments nitric oxide was supplied to the trees to react with ozone but this formed nitrogen dioxide, another phytotoxicant. The study showed that the photochemical smog complex reduced the rate of water, apparent photosynthesis and yield of both lemons and navel oranges. Fluoride levels in the atmosphere were too low to cause detectable effects. Leaf drop was significantly less in lemons receiving carbon filtered air than those receiving ''ambient air''.more » A similar trend occurred in navel oranges. Fruit drop is a serious problem in navel oranges. This loss was significantly less in carbon filtered air than ambient. Yield of mature fruit is reduced in some cases by as much as 50 percent.« less

  12. Cover Crops and Fertilization Alter Nitrogen Loss in Organic and Conventional Conservation Agriculture Systems

    PubMed Central

    Shelton, Rebecca E.; Jacobsen, Krista L.; McCulley, Rebecca L.

    2018-01-01

    Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), or a mix of the two (bi-culture); (2) an organic system with a hairy vetch cover crop employing three fertilization schemes (0 N, organic N, or a fertilizer N-credit approach); and (3) a conventional system with a winter wheat cover crop and three fertilization schemes (0 N, urea N, or organic N). In the unfertilized organic system, cover crop species affected NO3-N leaching (vetch > bi-culture > wheat) and N2O-N emissions and yield during corn growth (vetch, bi-culture > wheat). Fertilization increased soil inorganic N, gaseous N loss, N leaching, and yield in the organic vetch and conventional wheat systems. Fertilizer scheme affected the magnitude of growing season N2O-N loss in the organic vetch system (organic N > fertilizer N-credit) and the timing of loss (organic N delayed N2O-N loss vs. urea) and NO3-N leaching (urea >> organic N) in the conventional wheat system, but had no effect on yield. Cover crop selection and N fertilization techniques can reduce N leaching and greenhouse gas emissions without sacrificing yield, thereby enhancing N conservation in both organic and conventional conservation agriculture systems. PMID:29403512

  13. Variation in the flowering gene SELF PRUNING 5G promotes day-neutrality and early yield in tomato.

    PubMed

    Soyk, Sebastian; Müller, Niels A; Park, Soon Ju; Schmalenbach, Inga; Jiang, Ke; Hayama, Ryosuke; Zhang, Lei; Van Eck, Joyce; Jiménez-Gómez, José M; Lippman, Zachary B

    2017-01-01

    Plants evolved so that their flowering is triggered by seasonal changes in day length. However, day-length sensitivity in crops limits their geographical range of cultivation, and thus modification of the photoperiod response was critical for their domestication. Here we show that loss of day-length-sensitive flowering in tomato was driven by the florigen paralog and flowering repressor SELF-PRUNING 5G (SP5G). SP5G expression is induced to high levels during long days in wild species, but not in cultivated tomato because of cis-regulatory variation. CRISPR/Cas9-engineered mutations in SP5G cause rapid flowering and enhance the compact determinate growth habit of field tomatoes, resulting in a quick burst of flower production that translates to an early yield. Our findings suggest that pre-existing variation in SP5G facilitated the expansion of cultivated tomato beyond its origin near the equator in South America, and they provide a compelling demonstration of the power of gene editing to rapidly improve yield traits in crop breeding.

  14. Fast-ion transport in low density L-mode plasmas at TCV using FIDA spectroscopy and the TRANSP code

    NASA Astrophysics Data System (ADS)

    Geiger, B.; Karpushov, A. N.; Duval, B. P.; Marini, C.; Sauter, O.; Andrebe, Y.; Testa, D.; Marascheck, M.; Salewski, M.; Schneider, P. A.; the TCV Team; the EUROfusion MST1 Team

    2017-11-01

    Experiments with the new neutral beam injection source of TCV have been performed with high fast-ion fractions (>20%) that exhibit a clear reduction of the loop voltage and a clear increase of the plasma pressure in on- and off-axis heating configurations. However, good quantitative agreement between the experimental data and TRANSP predictions is only found when including strong additional fast-ion losses. These losses could in part be caused by turbulence or MHD activity as, e.g. high frequency modes near the frequency of toroidicity induced Alfvén eignmodes are observed. In addition, a newly installed fast-ion D-alpha (FIDA) spectroscopy system measures strong passive radiation and, hence, indicates the presence of high background neutral densities such that charge-exchange losses are substantial. Also the active radiation measured with the FIDA diagnostic, as well as data from a neutral particle analyzer, suggest strong fast-ion losses and large neutral densities. The large neutral densities can be justified since high electron temperatures (3-4 keV), combined with low electron densities (about 2× {10}19 m-3) yield long mean free paths of the neutrals which are penetrating from the walls.

  15. A two-photon laser induced fluorescence diagnostic with improved sensitivity, localization, and measurement rate

    NASA Astrophysics Data System (ADS)

    Elliott, Drew; Scime, Earl; Short, Zachary

    2016-10-01

    A two-photon absorption laser induced fluorescence diagnostic has been developed for measuring neutrals in fusion plasmas. Implementation of this diagnostic on the HIT-SI3 spheromak has demonstrated the sensitivity of the diagnostic and shown that measurements taken over several plasma pulses are possible. These measurements yielded an unexpected loss of signal when complex collection optics were utilized. Simulations show that this loss of signal can be explained by chromatic aberrations caused by the disparate Kr and D emission. This loss of signal has been addressed with the development of a new calibration scheme involving xenon gas. The Xe calibration scheme emission occurs at 656.00 nm while the deuterium emission is 656.09 nm. This nearly identical emission allows for advanced optical techniques such as confocal collection/injection and spatial filtering to be employed without loss of signal. Spatial filtering has been demonstrated to decrease noise while improving measurement localization, while confocal collection/injection allows for probing and measuring to occur through one viewport. The Xe scheme also allows for a Doppler-free hydrogen measurement. Doppler-free measurements eliminate the need to scan the laser spectrally thus greatly increasing the rate of measurement.

  16. Quantifying Soiling Loss Directly From PV Yield

    DOE PAGES

    Deceglie, Michael G.; Micheli, Leonardo; Muller, Matthew

    2018-01-23

    Soiling of photovoltaic (PV) panels is typically quantified through the use of specialized sensors. Here, we describe and validate a method for estimating soiling loss experienced by PV systems directly from system yield without the need for precipitation data. The method, termed the stochastic rate and recovery (SRR) method, automatically detects soiling intervals in a dataset, then stochastically generates a sample of possible soiling profiles based on the observed characteristics of each interval. In this paper, we describe the method, validate it against soiling station measurements, and compare it with other PV-yield-based soiling estimation methods. The broader application of themore » SRR method will enable the fleet scale assessment of soiling loss to facilitate mitigation planning and risk assessment.« less

  17. Quantifying Soiling Loss Directly From PV Yield

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

    Deceglie, Michael G.; Micheli, Leonardo; Muller, Matthew

    Soiling of photovoltaic (PV) panels is typically quantified through the use of specialized sensors. Here, we describe and validate a method for estimating soiling loss experienced by PV systems directly from system yield without the need for precipitation data. The method, termed the stochastic rate and recovery (SRR) method, automatically detects soiling intervals in a dataset, then stochastically generates a sample of possible soiling profiles based on the observed characteristics of each interval. In this paper, we describe the method, validate it against soiling station measurements, and compare it with other PV-yield-based soiling estimation methods. The broader application of themore » SRR method will enable the fleet scale assessment of soiling loss to facilitate mitigation planning and risk assessment.« less

  18. Electric treatment for hydrophilic ink deinking.

    PubMed

    Du, Xiaotang; Hsieh, Jeffery S

    2017-09-01

    Hydrophilic inks have been widely used due to higher printing speed, competitive cost and being healthy non-organic solvents. However, they cause problems in both product quality and process runnability due to their hydrophilic surface wettability, strong negative surface charge and sub-micron size. Electric treatment was shown to be able to increase the ink sizes from 60 nm to 700 nm through electrocoagulation and electrophoresis. In addition, electric treatment assisted flotation could reduce effective residual ink concentration (ERIC) by 90 ppm, compared with only 20 ppm by traditional flotation. Furthermore, the effect of electric treatment alone on ink separation was investigated by two anode materials, graphite and stainless steel. Both of them could remove hydrophilic inks with less than 1% yield loss via electroflotation and electrophoresis. But graphite is a better material as the anode because graphite reduced ERIC by an additional 100 ppm. The yield loss of flotation following electric treatment was also lower by 17% if graphite was the anode material. The difference between the two electrode materials resulted from electrocoagulation and ink redeposition during electric treatment. An electric pretreatment-flotation-hyperwashing process was conducted to understand the deinking performance in conditions similar to a paper mill, and the ERIC was reduced from 950 ppm to less than 400 ppm.

  19. Effects of temperature changes on maize production in Mozambique

    USGS Publications Warehouse

    Harrison, L.; Michaelsen, J.; Funk, Chris; Husak, G.

    2011-01-01

    We examined intraseasonal changes in maize phenology and heat stress exposure over the 1979-2008 period, using Mozambique meteorological station data and maize growth requirements in a growing degree-day model. Identifying historical effects of warming on maize growth is particularly important in Mozambique because national food security is highly dependent on domestic food production, most of which is grown in already warm to hot environments. Warming temperatures speed plant development, shortening the length of growth periods necessary for optimum plant and grain size. This faster phenological development also alters the timing of maximum plant water demand. In hot growing environments, temperature increases during maize pollination threaten to make midseason crop failure the norm. In addition to creating a harsher thermal environment, we find that early season temperature increases have caused the maize reproductive period to start earlier, increasing the risk of heat and water stress. Declines in time to maize maturation suggest that, independent of effects to water availability, yield potential is becoming increasingly limited by warming itself. Regional variations in effects are a function of the timing and magnitude of temperature increases and growing season characteristics. Continuation of current climatic trends could induce substantial yield losses in some locations. Farmers could avoid some losses through simple changes to planting dates and maize varietal types.

  20. Biotechnological advancement in genetic improvement of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

    PubMed

    Kumar, Pankaj; Srivastava, Dinesh Kumar

    2016-07-01

    With the advent of molecular biotechnology, plant genetic engineering techniques have opened an avenue for the genetic improvement of important vegetable crops. Vegetable crop productivity and quality are seriously affected by various biotic and abiotic stresses which destabilize rural economies in many countries. Moreover, absence of proper post-harvest storage and processing facilities leads to qualitative and quantitative losses. In the past four decades, conventional breeding has significantly contributed to the improvement of vegetable yields, quality, post-harvest life, and resistance to biotic and abiotic stresses. However, there are many constraints in conventional breeding, which can only be overcome by advancements made in modern biology. Broccoli (Brassica oleracea L. var. italica) is an important vegetable crop, of the family Brassicaceae; however, various biotic and abiotic stresses cause enormous crop yield losses during the commercial cultivation of broccoli. Thus, genetic engineering can be used as a tool to add specific characteristics to existing cultivars. However, a pre-requisite for transferring genes into plants is the availability of efficient regeneration and transformation techniques. Recent advances in plant genetic engineering provide an opportunity to improve broccoli in many aspects. The goal of this review is to summarize genetic transformation studies on broccoli to draw the attention of researchers and scientists for its further genetic advancement.

  1. Deletion of nfnAB in Thermoanaerobacterium saccharolyticum and Its Effect on Metabolism

    DOE PAGES

    Lo, Jonathan; Zheng, Tianyong; Olson, Daniel G.; ...

    2015-06-29

    NfnAB catalyzes the reversible transfer of electrons from reduced ferredoxin and NADH to 2 NADP +. The NfnAB complex has been hypothesized to be the main enzyme for ferredoxin oxidization in strains of Thermoanaerobacterium saccharolyticum engineered for increased ethanol production. NfnAB complex activity was detectable in crude cell extracts of T. saccharolyticum. In this paper, activity was also detected using activity staining of native PAGE gels. The nfnAB gene was deleted in different strains of T. saccharolyticum to determine its effect on end product formation. In wild-type T. saccharolyticum, deletion of nfnAB resulted in a 46% increase in H 2more » formation but otherwise little change in other fermentation products. In two engineered strains with 80% theoretical ethanol yield, loss of nfnAB caused two different responses: in one strain, ethanol yield decreased to about 30% of the theoretical value, while another strain had no change in ethanol yield. Biochemical analysis of cell extracts showed that the ΔnfnAB strain with decreased ethanol yield had NADPH-linked alcohol dehydrogenase (ADH) activity, while the ΔnfnAB strain with unchanged ethanol yield had NADH-linked ADH activity. Deletion of nfnAB caused loss of NADPH-linked ferredoxin oxidoreductase activity in all cell extracts. Significant NADH-linked ferredoxin oxidoreductase activity was seen in all cell extracts, including those that had lost nfnAB. This suggests that there is an unidentified NADH:ferredoxin oxidoreductase (distinct from nfnAB) playing a role in ethanol formation. The NfnAB complex plays a key role in generating NADPH in a strain that had become reliant on NADPH-ADH activity. Importance: Thermophilic anaerobes that can convert biomass-derived sugars into ethanol have been investigated as candidates for biofuel formation. Many anaerobes have been genetically engineered to increase biofuel formation; however, key aspects of metabolism remain unknown and poorly understood. One example is the mechanism for ferredoxin oxidation and transfer of electrons to NAD(P) +. The electron-bifurcating enzyme complex NfnAB is known to catalyze the reversible transfer of electrons from reduced ferredoxin and NADH to 2 NADP + and is thought to play key roles linking NAD(P)(H) metabolism with ferredoxin metabolism. Finally, we report the first deletion of nfnAB and demonstrate a role for NfnAB in metabolism and ethanol formation in Thermoanaerobacterium saccharolyticum and show that this may be an important feature among other thermophilic ethanologenic anaerobes.« less

  2. Effect of N Fertilization Pattern on Rice Yield, N Use Efficiency and Fertilizer–N Fate in the Yangtze River Basin, China

    PubMed Central

    Liu, Xiaowei; Wang, Huoyan; Zhou, Jianmin; Hu, Fengqin; Zhu, Dejin; Chen, Zhaoming; Liu, Yongzhe

    2016-01-01

    High N loss and low N use efficiency (NUE), caused by high N fertilizer inputs and inappropriate fertilization patterns, have become important issues in the rice (Oryza sativa L.) growing regions of southern China. Changing current farmer fertilizer practice (FFP, 225 kg ha–1 N as three applications, 40% as basal fertilizer, 30% as tillering fertilizer and 30% as jointing fertilizer) to one—time root—zone fertilization (RZF, 225 kg ha–1 N applied once into 10 cm deep holes positioned 5 cm from the rice root as basal fertilizer) will address this problem. A two—year field experiment covering two rice growing regions was conducted to investigate the effect of urea one—time RZF on rice growth, nutrient uptake, and NUE. The highest NH4+–N content for RZF at fertilizer point at 30 d and 60 d after fertilization were 861.8 and 369.9 mg kg–1 higher than FFP, respectively. Rice yield and total N accumulation of RZF increased by 4.3–44.9% and 12.7–111.2% compared to FFP, respectively. RZF reduced fertilizer—N loss by 56.3–81.9% compared to FFP. The NUEs following RZF (mean of 65.8% for the difference method and 43.7% for the labelled method) were significantly higher than FFP (mean of 35.7% for the difference method and 14.4% for the labelled method). In conclusion, RZF maintained substantial levels of fertilizer—N in the root—zone, which led to enhanced rice biomass and N uptake during the early growth stages, increased fertilizer—N residual levels and reduced fertilizer—N loss at harvest. RZF produced a higher yield increment and showed an increased capacity to resist environmental threats than FFP in sandy soils. Therefore, adopting suitable fertilizer patterns plays a key role in enhancing agricultural benefits. PMID:27861491

  3. Therapy-induced selective loss of leukemia-initiating activity in murine adult T cell leukemia

    PubMed Central

    El Hajj, Hiba; El-Sabban, Marwan; Hasegawa, Hideki; Zaatari, Ghazi; Ablain, Julien; Saab, Shahrazad T.; Janin, Anne; Mahfouz, Rami; Nasr, Rihab; Kfoury, Youmna; Nicot, Christophe; Hermine, Olivier; Hall, William

    2010-01-01

    Chronic HTLV-I (human T cell lymphotropic virus type I) infection may cause adult T cell leukemia/lymphoma (ATL), a disease with dismal long-term prognosis. The HTLV-I transactivator, Tax, initiates ATL in transgenic mice. In this study, we demonstrate that an As2O3 and IFN-α combination, known to trigger Tax proteolysis, cures Tax-driven ATL in mice. Unexpectedly, this combination therapy abrogated initial leukemia engraftment into secondary recipients, whereas the primary tumor bulk still grew in the primary hosts, only to ultimately abate later on. This loss of initial transplantability required proteasome function. A similar regimen recently yielded unprecedented disease control in human ATL. Our demonstration that this drug combination targeting Tax stability abrogates tumor cell immortality but not short-term growth may foretell a favorable long-term efficiency of this regimen in patients. PMID:21135137

  4. Identification of Critical Erosion Prone Areas and Computation of Sediment Yield Using Remote Sensing and GIS: A Case Study on Sarada River Basin

    NASA Astrophysics Data System (ADS)

    Sundara Kumar, P.; Venkata Praveen, T.; Anjanaya Prasad, M.; Santha Rao, P.

    2018-06-01

    The two most important resources blessed by nature to the mankind are land and water. Undoubtedly, these gifts have to be conserved and maintained with unflinching efforts from every one of us for an effective environmental and ecological balance. The efforts and energy of water resources engineers and conservationists are going in this direction to conserve these precious resources of nature. The present study is an attempt to develop suitable methodology to facilitate decision makers to conserve the resources and also reflects the cause mentioned above has been presented here. The main focus of this study is to identify the critical prone areas for soil erosion and computation of sediment yield in a small basin using Universal Soil Loss Equation and Modified Universal Soil Loss Equation (MUSLE) respectively. The developed model has been applied on Sarada river basin which has a drainage area of 1252.99 km2. This river is located in Andhra Pradesh State (AP), India. The basin has been divided into micro basins for effective estimation and also for precise identification of the areas that are prone to soil erosion. Remote Sensing and Geographic Information Systems tools were used to generate and spatially organize the data that is required for soil erosion modeling. It was found that the micro basins with very severe soil erosion are consisting of hilly areas with high topographic factor and 38.01% of the study area has the rate erosion more than 20 t/ha/year and hence requires an immediate attention from the soil conservation point of view. In this study region, though there is one discharge measuring gauge station available at Anakapalli but there is no sediment yield gauging means available to compute the sediment yield. Therefore, to arrive at the suspended-sediment concentration was a challenge task. In the present study the sediment measurement has been carried out with an instrument (DH-48), sediment sampling equipment as per IS: 4890-1968, has been used. Suspended-sediment samples were collected and sediment yield was arrived at the site by using this instrument. The sediment yield was also computed using MUSLE. Data for this model study has been generated from the samples collected from 28 storm events spread over a time span of 1 year, at the outlet of the basin at Anakapalli for computation of sediment yield. The sediment yield as estimated by MUSLE model has been successfully compared with the sediment yield measured at the outlet of the basin by sediment yield measuring unit and found fairly good correlation between them. Hence the developed methodology will be useful to estimate the sediment yield in the hydrologically similar basins that are not gauged for sediment yield.

  5. Enhanced Photolysis of Nucleic Acid Monomers by Pyrophosphate in the Simulated Primitive Soup

    NASA Astrophysics Data System (ADS)

    Kongjiang, Wang; Zhifang, Chai; Xianming, Pan

    1999-05-01

    In our simulation of the photochemistry of the primitive soup, it was found that yield of chromophore loss of some nucleic acid bases, nucleosides and nucleotides [NA] undergoing ultraviolet radiation by medium pressure mercury lamp [MPML] was enhanced by pyrophosphate and triphosphate whether O2 is present or not. The yield of chromophore loss of guanosine, uracil, 5' CMP, and the derivatives of adenine and thymine was observed to rise with the increase of molar concentration of pyrophosphate in N2-saturated systems. In air-saturated samples, increase in yield of chromophore loss was observed when the concentration of pyrophosphate reaches 5×10-4 M, relative yield of chromophore loss (CLrel) coming to maximum in the range from 0.01 to 0.1 M, followed by a slight decline with the further increase of pyrophosphate concentration. The enhancement of photolysis of NA by pyrophosphate was due to the interaction between NA and pyrophosphate radicals photoionized by UV quanta of wavelength less than about 210 nm in the emission spectrum of a MPML. The relevance of this phenomenon to the origin of life has been discussed as well.

  6. Ascochyta blight of chickpea: production of phytotoxins and disease management.

    PubMed

    Shahid, Ahmad Ali; Husnain, Tayyab; Riazuddin, Sheikh

    2008-01-01

    Ascochyta blight caused by Ascochyta rabiei (Pass.) Lab., is the most devastating disease of chickpea and can occur anywhere the crop is grown. Several epidemics of blight causing complete yield losses have been reported. Despite extensive pathological and molecular studies, the nature and extent of pathogenic variability in A. rabiei have not been clearly established. Several isolates of A. rabiei were grown in liquid culture medium which secreted phytotoxic compounds of solanapyrone A, B, C and cytochalasin D. The same fungal metabolites were also recovered from extract of naturally blight stricken chickpea plants. Toxicity of purified solanapyrones as determined by cell bioassay was in the order of solanapyrone A>solanapyrone B>solanapyrone C. However, the specificity of all three compounds was dependent on the genetic identity of the chickpea cultivars. Seed treatment and foliar application of fungicides are commonly recommended for disease management, but further information on biology and survival of A. rabiei is needed to devise more effective management strategies. A short description of chickpea blight, geographical distribution, disease cycle, symptoms, losses, production of phytotoxins and disease management practices for the control of Ascochyta blight will be discussed in this review article.

  7. Mechanisms and causes of wear in tooth enamel: implications for hominin diets.

    PubMed

    Lucas, Peter W; Omar, Ridwaan; Al-Fadhalah, Khaled; Almusallam, Abdulwahab S; Henry, Amanda G; Michael, Shaji; Thai, Lidia Arockia; Watzke, Jörg; Strait, David S; Atkins, Anthony G

    2013-03-06

    The wear of teeth is a major factor limiting mammalian lifespans in the wild. One method of describing worn surfaces, dental microwear texture analysis, has proved powerful for reconstructing the diets of extinct vertebrates, but has yielded unexpected results in early hominins. In particular, although australopiths exhibit derived craniodental features interpreted as adaptations for eating hard foods, most do not exhibit microwear signals indicative of this diet. However, no experiments have yet demonstrated the fundamental mechanisms and causes of this wear. Here, we report nanowear experiments where individual dust particles, phytoliths and enamel chips were slid across a flat enamel surface. Microwear features produced were influenced strongly by interacting mechanical properties and particle geometry. Quartz dust was a rigid abrasive, capable of fracturing and removing enamel pieces. By contrast, phytoliths and enamel chips deformed during sliding, forming U-shaped grooves or flat troughs in enamel, without tissue loss. Other plant tissues seem too soft to mark enamel, acting as particle transporters. We conclude that dust has overwhelming importance as a wear agent and that dietary signals preserved in dental microwear are indirect. Nanowear studies should resolve controversies over adaptive trends in mammals like enamel thickening or hypsodonty that delay functional dental loss.

  8. Impact of water control projects on fisheries resources in Bangladesh

    NASA Astrophysics Data System (ADS)

    Mirza, Monirul Qader; Ericksen, Neil J.

    1996-07-01

    Bangladesh is a very flat delta built up by the Ganges—Brahmaputra—Meghna/Barak river systems. Because of its geographical location, floods cause huge destruction of lives and properties almost every year. Water control programs have been undertaken to enhance development through mitigating the threat of disasters. This structural approach to flood hazard has severely affected floodplain fisheries that supply the major share of protein to rural Bangladesh, as exemplified by the Chandpur Irrigation Project. Although the regulated environment of the Chandpur project has become favorable for closed-water cultured fish farming, the natural open-water fishery loss has been substantial. Results from research show that fish yields were better under preproject conditions. Under project conditions per capita fish consumption has dropped significantly, and the price of fish has risen beyond the means of the poor people, so that fish protein in the diet of poor people is gradually declining. Bangladesh is planning to expand water control facilities to the remaining flood-prone areas in the next 15 20 years. This will cause further loss of floodplain fisheries. If prices for closed-water fish remain beyond the buying power of the poor, alternative sources of cheap protein will be required.

  9. A banana NAC transcription factor (MusaSNAC1) impart drought tolerance by modulating stomatal closure and H2O2 content.

    PubMed

    Negi, Sanjana; Tak, Himanshu; Ganapathi, T R

    2018-03-01

    MusaSNAC1 function in H 2 O 2 mediated stomatal closure and promote drought tolerance by directly binding to CGT[A/G] motif in regulatory region of multiple stress-related genes. Drought is a abiotic stress-condition, causing reduced plant growth and diminished crop yield. Guard cells of the stomata control photosynthesis and transpiration by regulating CO 2 exchange and water loss, thus affecting growth and crop yield. Roles of NAC (NAM, ATAF1/2 and CUC2) protein in regulation of stress-conditions has been well documented however, their control over stomatal aperture is largely unknown. In this study we report a banana NAC protein, MusaSNAC1 which induced stomatal closure by elevating H 2 O 2 content in guard cells during drought stress. Overexpression of MusaSNAC1 in banana resulted in higher number of stomata closure causing reduced water loss and thus elevated drought-tolerance. During drought, expression of GUS (β-glucuronidase) under P MusaSNAC1 was remarkably elevated in guard cells of stomata which correlated with its function as a transcription factor regulating stomatal aperture closing. MusaSNAC1 is a transcriptional activator belonging to SNAC subgroup and its 5'-upstream region contain multiple Dof1 elements as well as stress-associated cis-elements. Moreover, MusaSNAC1 also regulate multiple stress-related genes by binding to core site of NAC-proteins CGT[A/G] in their 5'-upstream region. Results indicated an interesting mechanism of drought tolerance through stomatal closure by H 2 O 2 generation in guard cells, regulated by a NAC-protein in banana.

  10. A comprehensive transcriptome analysis of silique development and dehiscence in Arabidopsis and Brassica integrating genotypic, interspecies and developmental comparisons.

    PubMed

    Jaradat, Masrur R; Ruegger, Max; Bowling, Andrew; Butler, Holly; Cutler, Adrian J

    2014-01-01

    Asynchronous flowering of Brassica napus (canola) leads to seeds and siliques at varying stages of maturity as harvest approaches. This range of maturation can result in premature silique dehiscence (pod shattering), resulting in yield losses, which may be worsened by environmental stresses. Therefore, a goal for canola crop improvement is to reduce shattering in order to maximize yield. We performed a comprehensive transcriptome analysis on the dehiscence zone (DZ) and valve of Arabidopsis and Brassica siliques in shatter resistant and sensitive genotypes at several developmental stages. Among known Arabidopsis dehiscence genes, we confirmed that homologs of SHP1/2, FUL, ADPG1, NST1/3 and IND were associated with shattering in B. juncea and B. napus. We noted a correlation between reduced pectin degradation genes and shatter-resistance. Tension between lignified and non-lignified cells in the silique DZ plays a major role in dehiscence. Light microscopy revealed a smaller non-lignified separation layer in relatively shatter-resistant B. juncea relative to B. napus and this corresponded to increased expression of peroxidases involved in monolignol polymerization. Sustained repression of auxin biosynthesis, transport and signaling in B. juncea relative to B. napus may cause differences in dehiscence zone structure and cell wall constituents. Tension on the dehiscence zone is a consequence of shrinkage and loss of flexibility in the valves, which is caused by senescence and desiccation. Reduced shattering was generally associated with upregulation of ABA signaling and down-regulation of ethylene and jasmonate signaling, corresponding to more pronounced stress responses and reduced senescence and photosynthesis. Overall, we identified 124 cell wall related genes and 103 transcription factors potentially involved in silique dehiscence.

  11. A comprehensive transcriptome analysis of silique development and dehiscence in Arabidopsis and Brassica integrating genotypic, interspecies and developmental comparisons

    PubMed Central

    Jaradat, Masrur R; Ruegger, Max; Bowling, Andrew; Butler, Holly; Cutler, Adrian J

    2014-01-01

    Asynchronous flowering of Brassica napus (canola) leads to seeds and siliques at varying stages of maturity as harvest approaches. This range of maturation can result in premature silique dehiscence (pod shattering), resulting in yield losses, which may be worsened by environmental stresses. Therefore, a goal for canola crop improvement is to reduce shattering in order to maximize yield. We performed a comprehensive transcriptome analysis on the dehiscence zone (DZ) and valve of Arabidopsis and Brassica siliques in shatter resistant and sensitive genotypes at several developmental stages. Among known Arabidopsis dehiscence genes, we confirmed that homologs of SHP1/2, FUL, ADPG1, NST1/3 and IND were associated with shattering in B. juncea and B. napus. We noted a correlation between reduced pectin degradation genes and shatter-resistance. Tension between lignified and non-lignified cells in the silique DZ plays a major role in dehiscence. Light microscopy revealed a smaller non-lignified separation layer in relatively shatter-resistant B. juncea relative to B. napus and this corresponded to increased expression of peroxidases involved in monolignol polymerization. Sustained repression of auxin biosynthesis, transport and signaling in B. juncea relative to B. napus may cause differences in dehiscence zone structure and cell wall constituents. Tension on the dehiscence zone is a consequence of shrinkage and loss of flexibility in the valves, which is caused by senescence and desiccation. Reduced shattering was generally associated with upregulation of ABA signaling and down-regulation of ethylene and jasmonate signaling, corresponding to more pronounced stress responses and reduced senescence and photosynthesis. Overall, we identified 124 cell wall related genes and 103 transcription factors potentially involved in silique dehiscence. PMID:25523176

  12. An efficient scan diagnosis methodology according to scan failure mode for yield enhancement

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Tae; Seo, Nam-Sik; Oh, Ghil-Geun; Kim, Dae-Gue; Lee, Kyu-Taek; Choi, Chi-Young; Kim, InSoo; Min, Hyoung Bok

    2008-12-01

    Yield has always been a driving consideration during fabrication of modern semiconductor industry. Statistically, the largest portion of wafer yield loss is defective scan failure. This paper presents efficient failure analysis methods for initial yield ramp up and ongoing product with scan diagnosis. Result of our analysis shows that more than 60% of the scan failure dies fall into the category of shift mode in the very deep submicron (VDSM) devices. However, localization of scan shift mode failure is very difficult in comparison to capture mode failure because it is caused by the malfunction of scan chain. Addressing the biggest challenge, we propose the most suitable analysis method according to scan failure mode (capture / shift) for yield enhancement. In the event of capture failure mode, this paper describes the method that integrates scan diagnosis flow and backside probing technology to obtain more accurate candidates. We also describe several unique techniques, such as bulk back-grinding solution, efficient backside probing and signal analysis method. Lastly, we introduce blocked chain analysis algorithm for efficient analysis of shift failure mode. In this paper, we contribute to enhancement of the yield as a result of the combination of two methods. We confirm the failure candidates with physical failure analysis (PFA) method. The direct feedback of the defective visualization is useful to mass-produce devices in a shorter time. The experimental data on mass products show that our method produces average reduction by 13.7% in defective SCAN & SRAM-BIST failure rates and by 18.2% in wafer yield rates.

  13. Organic Biochar Based Fertilization

    NASA Astrophysics Data System (ADS)

    Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

    2017-04-01

    Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.

  14. Rooting traits of peanut genotypes with different yield responses to terminal drought

    USDA-ARS?s Scientific Manuscript database

    Drought at pod filling can severely reduce yield of peanut. Better root systems can reduce yield loss from drought. However, the relationship of root characters with yield under terminal drought is not well understood. The objective of this study was to investigate the responses of peanut genotyp...

  15. Type 1 Diabetes in Young Rats Leads to Progressive Trabecular Bone Loss, Cessation of Cortical Bone Growth, and Diminished Whole Bone Strength and Fatigue Life

    PubMed Central

    Silva, Matthew J.; Brodt, Michael D.; Lynch, Michelle A.; McKenzie, Jennifer A.; Tanouye, Kristi M.; Nyman, Jeffry S.; Wang, Xiaodu

    2009-01-01

    People with diabetes have increased risk of fracture disproportionate to BMD, suggesting reduced material strength (quality). We quantified the skeletal effects of type 1 diabetes in the rat. Fischer 344 and Sprague-Dawley rats (12 wk of age) were injected with either vehicle (Control) or streptozotocin (Diabetic). Forelimbs were scanned at 0, 4, 8, and 12 wk using pQCT. Rats were killed after 12 wk. We observed progressive osteopenia in diabetic rats. Trabecular osteopenia was caused by bone loss: volumetric BMD decreased progressively with time in diabetic rats but was constant in controls. Cortical osteopenia was caused by premature arrest of cortical expansion: cortical area did not increase after 4–8 wk in diabetic rats but continued to increase in controls. Postmortem μCT showed a 60% reduction in proximal tibial trabecular BV/TV in diabetic versus control rats, whereas moments of inertia of the ulnar and femoral diaphysis were reduced ∼30%. Monotonic bending tests indicated that ulna and femora from diabetic animals were ∼25% less stiff and strong versus controls. Estimates of material properties indicated no changes in elastic modulus or ultimate stress but modest (∼10%) declines in yield stress for diabetic bone. These changes were associated with a ∼50% increase in the nonenzymatic collagen cross-link pentosidine. Last, cyclic testing showed diminished fatigue life in diabetic bones at the structural (force) level but not at the material (stress) level. In summary, type 1 diabetes, left untreated, causes trabecular bone loss and a reduction in diaphyseal growth. Diabetic bone has greatly increased nonenzymatic collagen cross-links but only modestly reduced material properties. The loss of whole bone strength under both monotonic and fatigue loading is attributed mainly to reduced bone size. PMID:19338453

  16. Role of JAK/STAT signaling in neuroepithelial stem cell maintenance and proliferation in the Drosophila optic lobe

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

    Wang, Wei; Li, Yonggang; Zhou, Liya

    2011-07-15

    Highlights: {yields} JAK/STAT activity is graded in the Drosophila optic lobe neuroepithelium. {yields} Inactivation of JAK signaling causes disintegration of the optic lobe neuroepithelium and depletion of the neuroepithelial stem cells. {yields} JAK pathway overactivation promotes neuroepithelial overgrowth. {yields} Notch signaling acts downstream of JAK/STAT to promote neuroepithelial growth and expansion. -- Abstract: During Drosophila optic lobe development, proliferation and differentiation must be tightly modulated to reach its normal size for proper functioning. The JAK/STAT pathway plays pleiotropic roles in Drosophila development and in the larval brain, has been shown to inhibit medulla neuroblast formation. In this study, we findmore » that JAK/STAT activity is required for the maintenance and proliferation of the neuroepithelial stem cells in the optic lobe. In loss-of-function JAK/STAT mutant brains, the neuroepithelial cells lose epithelial cell characters and differentiate prematurely while ectopic activation of this pathway is sufficient to induce neuroepithelial overgrowth in the optic lobe. We further show that Notch signaling acts downstream of JAK/STAT to control the maintenance and growth of the optic lobe neuroepithelium. Thus, in addition to its role in suppression of neuroblast formation, the JAK/STAT pathway is necessary and sufficient for optic lobe neuroepithelial growth.« less

  17. Irrigated mountain meadow fertilizer application timing effects on overland flow water quality.

    PubMed

    White, Shawn K; Brummer, Joe E; Leininger, Wayne C; Frasier, Gary W; Waskom, Reagan M; Bauder, Troy A

    2003-01-01

    Nonpoint-source pollution from agricultural activities is currently the leading cause of degradation of waterways in the United States. Applying best management practices to flood-irrigated mountain meadows may improve agricultural runoff and return flow water quality. Prior research has focused on fertilizer use for increased hay yields, while few studies have investigated the environmental implications of this practice. We examined the effects of fertilizer application timing on overland flow water quality from an irrigated mountain meadow near Gunnison, Colorado. Application of 40 kg phosphorus (P) and 19 kg nitrogen (N) ha(-1) using monoammonium phosphate (11-52-0, N-P-K) fertilizer to plots in the fall significantly reduced concentrations of reactive P and ammonium N in irrigation overland flow compared with early or late spring fertilization. Reactive P loading was 9 to almost 16 times greater when fertilizer was applied in the early or late spring, respectively, compared with in the fall. Ammonium N followed a similar trend with early spring loading more than 18 times greater and late spring loading more than 34 times greater than loads from fall-fertilized plots. Losses of 45% of the applied P and more than 17% of the N were measured in runoff when fertilizer was applied in the late spring. These results, coupled with those from previous studies, suggest that mountain meadow hay producers should apply fertilizer in the fall, especially P-based fertilizers, to improve hay yields, avoid economic losses from loss of applied fertilizers, and reduce the potential for impacts to water quality.

  18. In-vitro inhibiton of Pantoea ananatis by antagonistic bacteria

    NASA Astrophysics Data System (ADS)

    Karagöz, Kenan

    2017-04-01

    Like most cultivated crops, onions (Allium cepa L.) are plagued by phytopathogenic bacteria. Although bacterial diseases of onion occur sporadically, they can cause loss of yield, in the range of a few percent up to 40%. Center rot of onion caused by Pantoea ananatis is the one of the major bacterial disease. Cultural methods and copper compounds often are recommended for control of bacterial diseases, but these are insufficient and the use of some chemicals has adverse effects. For these reasons, biological control is important manner for control of plant disease. In this study; it was researched that in-vitro inhibition effect of 271bacterial strains on P. ananatis in-vitro. Commercially available streptomycin, kanamycin and tetracycline disks were used as control. In consequence; three isolates show more or less inhibitory effect against P. ananatis.

  19. Trade-off between reservoir yield and evaporation losses as a function of lake morphology in semi-arid Brazil.

    PubMed

    Campos, José N B; Lima, Iran E; Studart, Ticiana M C; Nascimento, Luiz S V

    2016-05-31

    This study investigates the relationships between yield and evaporation as a function of lake morphology in semi-arid Brazil. First, a new methodology was proposed to classify the morphology of 40 reservoirs in the Ceará State, with storage capacities ranging from approximately 5 to 4500 hm3. Then, Monte Carlo simulations were conducted to study the effect of reservoir morphology (including real and simplified conical forms) on the water storage process at different reliability levels. The reservoirs were categorized as convex (60.0%), slightly convex (27.5%) or linear (12.5%). When the conical approximation was used instead of the real lake form, a trade-off occurred between reservoir yield and evaporation losses, with different trends for the convex, slightly convex and linear reservoirs. Using the conical approximation, the water yield prediction errors reached approximately 5% of the mean annual inflow, which is negligible for large reservoirs. However, for smaller reservoirs, this error became important. Therefore, this paper presents a new procedure for correcting the yield-evaporation relationships that were obtained by assuming a conical approximation rather than the real reservoir morphology. The combination of this correction with the Regulation Triangle Diagram is useful for rapidly and objectively predicting reservoir yield and evaporation losses in semi-arid environments.

  20. Mechanisms of electron acceptor utilization: Implications for simulating anaerobic biodegradation

    USGS Publications Warehouse

    Schreiber, M.E.; Carey, G.R.; Feinstein, D.T.; Bahr, J.M.

    2004-01-01

    Simulation of biodegradation reactions within a reactive transport framework requires information on mechanisms of terminal electron acceptor processes (TEAPs). In initial modeling efforts, TEAPs were approximated as occurring sequentially, with the highest energy-yielding electron acceptors (e.g. oxygen) consumed before those that yield less energy (e.g., sulfate). Within this framework in a steady state plume, sequential electron acceptor utilization would theoretically produce methane at an organic-rich source and Fe(II) further downgradient, resulting in a limited zone of Fe(II) and methane overlap. However, contaminant plumes often display much more extensive zones of overlapping Fe(II) and methane. The extensive overlap could be caused by several abiotic and biotic processes including vertical mixing of byproducts in long-screened monitoring wells, adsorption of Fe(II) onto aquifer solids, or microscale heterogeneity in Fe(III) concentrations. Alternatively, the overlap could be due to simultaneous utilization of terminal electron acceptors. Because biodegradation rates are controlled by TEAPs, evaluating the mechanisms of electron acceptor utilization is critical for improving prediction of contaminant mass losses due to biodegradation. Using BioRedox-MT3DMS, a three-dimensional, multi-species reactive transport code, we simulated the current configurations of a BTEX plume and TEAP zones at a petroleum- contaminated field site in Wisconsin. Simulation results suggest that BTEX mass loss due to biodegradation is greatest under oxygen-reducing conditions, with smaller but similar contributions to mass loss from biodegradation under Fe(III)-reducing, sulfate-reducing, and methanogenic conditions. Results of sensitivity calculations document that BTEX losses due to biodegradation are most sensitive to the age of the plume, while the shape of the BTEX plume is most sensitive to effective porosity and rate constants for biodegradation under Fe(III)-reducing and methanogenic conditions. Using this transport model, we had limited success in simulating overlap of redox products using reasonable ranges of parameters within a strictly sequential electron acceptor utilization framework. Simulation results indicate that overlap of redox products cannot be accurately simulated using the constructed model, suggesting either that Fe(III) reduction and methanogenesis are occurring simultaneously in the source area, or that heterogeneities in Fe(III) concentration and/or mineral type cause the observed overlap. Additional field, experimental, and modeling studies will be needed to address these questions. ?? 2004 Elsevier B.V. All rights reserved.

  1. Leveraging Electron Transfer Dissociation for Site Selective Radical Generation: Applications for Peptide Epimer Analysis

    NASA Astrophysics Data System (ADS)

    Lyon, Yana A.; Beran, Gregory; Julian, Ryan R.

    2017-07-01

    Traditional electron-transfer dissociation (ETD) experiments operate through a complex combination of hydrogen abundant and hydrogen deficient fragmentation pathways, yielding c and z ions, side-chain losses, and disulfide bond scission. Herein, a novel dissociation pathway is reported, yielding homolytic cleavage of carbon-iodine bonds via electronic excitation. This observation is very similar to photodissociation experiments where homolytic cleavage of carbon-iodine bonds has been utilized previously, but ETD activation can be performed without addition of a laser to the mass spectrometer. Both loss of iodine and loss of hydrogen iodide are observed, with the abundance of the latter product being greatly enhanced for some peptides after additional collisional activation. These observations suggest a novel ETD fragmentation pathway involving temporary storage of the electron in a charge-reduced arginine side chain. Subsequent collisional activation of the peptide radical produced by loss of HI yields spectra dominated by radical-directed dissociation, which can be usefully employed for identification of peptide isomers, including epimers.

  2. An assessment of climate change impacts on maize yields in Hebei Province of China.

    PubMed

    Chen, Yongfu; Han, Xinru; Si, Wei; Wu, Zhigang; Chien, Hsiaoping; Okamoto, Katsuo

    2017-03-01

    The climate change impacts on maize yields are quantified in this paper using statistical models with panel data from 3731 farmers' observations across nine sample villages in Hebei Province of China. The marginal impacts of climate change and the simulated impacts on maize yields based on scenarios of Representative Concentration Pathways 2.6, 4.5, 6.0, and 8.5 from the global climate models of Model for Interdisciplinary Research on Climate version 5 (MIROC5) and Meteorological Research Institute Coupled General Circulation Model version 3 (MRI-CGCM3) were then calculated, analyzed, and explained. The results indicate that, first, the most important finding was that climate change impacts on maize yields were significant and a 1°C warming or a 1mm decrease in precipitation resulted in a 150.255kg or a 1.941kg loss in maize yields per hectare, respectively. Second, villages with latitudes of less than 39.832 and longitudes of more than 114.839 in Hebei province suffered losses due to warm weather. Third, the simulated impacts for the full sample are all negative based on scenarios from MIROC5, and their magnitudes are more than those of MRI-CGCM3 are. Based on scenarios in the 2050s, the biggest loss for maize yields per hectare for the full sample accounts for about one-tenth of the mean maize yield from 2004 to 2010, and all of the villages are impacted. Hence, it is important to help farms adopt an adaptation strategy to tackle the risk of loss for maize yields from climate change, and it is necessary to develop agricultural synthesis services as a public adaptation policy at the village level to interact with the adaptation strategy at the farm level. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Is Yield Increase Sufficient to Achieve Food Security in China?

    PubMed Central

    Wei, Xing; Zhang, Zhao; Shi, Peijun; Wang, Pin; Chen, Yi; Song, Xiao; Tao, Fulu

    2015-01-01

    Increasing demand for food, driven by unprecedented population growth and increasing consumption, will keep challenging food security in China. Although cereal yields have substantially improved during the last three decades, whether it will keep thriving to meet the increasing demand is not known yet. Thus, an integrated analysis on the trends of crop yield and cultivated area is essential to better understand current state of food security in China, especially on county scale. So far, yield stagnation has extensively dominated the main cereal-growing areas across China. Rice yield is facing the most severe stagnation that 53.9% counties tracked in the study have stagnated significantly, followed by maize (42.4%) and wheat (41.9%). As another important element for production sustainability, but often neglected is the planted area patterns. It has been further demonstrated that the loss in productive arable land for rice and wheat have dramatically increased the pressure on achieving food security. Not only a great deal of the planted areas have stagnated since 1980, but also collapsed. 48.4% and 54.4% of rice- and wheat-growing counties have lost their cropland areas to varying degrees. Besides, 27.6% and 35.8% of them have retrograded below the level of the 1980s. The combined influence (both loss in yield and area) has determined the crop sustainable production in China to be pessimistic for rice and wheat, and consequently no surprise to find that more than half of counties rank a lower level of production sustainability. Therefore, given the potential yield increase in wheat and maize, as well as substantial area loss of rice and wheat, the possible targeted adaptation measures for both yield and cropping area is required at county scale. Moreover, policies on food trade, alongside advocation of low calorie diets, reducing food loss and waste can help to enhance food security. PMID:25680193

  4. Protothecal enteritis as a cause of protein-losing enteropathy in a bull.

    PubMed

    Osterstock, Jason B; Mansell, Joanne L; Roussel, Allen J

    2005-11-01

    Prototheca spp are achlorophyllic saprophytic algae found in wastewater, sewage, agricultural waste, and possibly elsewhere in the environment. Infections with these organisms have been reported in cattle, humans, and dogs; affected cattle commonly develop mastitis. A 5-year-old Brahman-cross bull was evaluated because of a history of diarrhea and weight loss. The history and physical examination and clinicopathologic findings were similar to those associated with granulomatous enteritis caused by Mycobacterium avium subsp paratuberculosis (Johne's disease), which is the most common protein-losing enteropathy of cattle. However, diagnostic tests for paratuberculosis yielded negative results. Biopsy specimens from the ileum, jejunum, and ileocecal lymph node were collected for histologic examination and preparation of tissue impression smears; Prototheca-like organisms were identified. Because of the poor prognosis associated with this infection and the lack of safe and economical therapeutic agents for cattle, the owner decided to euthanatize the bull. Infection with Prototheca organisms was confirmed postmortem. As this case illustrates, protothecosis may be a cause of granulomatous enteritis in cattle.

  5. [Further reduction of nitrogen fertilizer application in paddy field under green manuring of Taihu Area, China].

    PubMed

    Zhao, Dong; Yan, Ting-mei; Qiao, Jun; Yang, Lin-zhang; Tang, Fang; Song, Yun-fei

    2015-06-01

    This study focused on the nitrogen loss via runoff, change of nitrogen in different forms in surface water in paddy field, and grain yield, through further reduction of nitrogen fertilizer application rate under green manuring without basal dressing. Results showed that with 150 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil, no basal dressing could not only sharply reduce N concentration in surface water and decrease 17.2% of N loss, but also increase 2.8% of grain yield in comparison with basal dressing. It was a worthwhile farming method that inorganic nitrogen fertilizer was not used for basal dressing but for topdressing after return of green ma- nure to soil in Taihu Area. However, the grain yield would decrease if the rate of topdressing nitro- gen was excessively reduced or increased. After all, it was feasible to realize harmonization of grain yield and environmental benefits in Taihu Area, with 133 kg · hm(-2) inorganic N fertilizer input after return of green manure to soil as well as no application of basal dressing, which could greatly reduce N fertilizer input and N loss as well as ensure rice yield.

  6. Impacts of Soil and Water Conservation Practices on Crop Yield, Run-off, Soil Loss and Nutrient Loss in Ethiopia: Review and Synthesis.

    PubMed

    Adimassu, Zenebe; Langan, Simon; Johnston, Robyn; Mekuria, Wolde; Amede, Tilahun

    2017-01-01

    Research results published regarding the impact of soil and water conservation practices in the highland areas of Ethiopia have been inconsistent and scattered. In this paper, a detailed review and synthesis is reported that was conducted to identify the impacts of soil and water conservation practices on crop yield, surface run-off, soil loss, nutrient loss, and the economic viability, as well as to discuss the implications for an integrated approach and ecosystem services. The review and synthesis showed that most physical soil and water conservation practices such as soil bunds and stone bunds were very effective in reducing run-off, soil erosion and nutrient depletion. Despite these positive impacts on these services, the impact of physical soil and water conservation practices on crop yield was negative mainly due to the reduction of effective cultivable area by soil/stone bunds. In contrast, most agronomic soil and water conservation practices increase crop yield and reduce run-off and soil losses. This implies that integrating physical soil and water conservation practices with agronomic soil and water conservation practices are essential to increase both provisioning and regulating ecosystem services. Additionally, effective use of unutilized land (the area occupied by bunds) by planting multipurpose grasses and trees on the bunds may offset the yield lost due to a reduction in planting area. If high value grasses and trees can be grown on this land, farmers can harvest fodder for animals or fuel wood, both in scarce supply in Ethiopia. Growing of these grasses and trees can also help the stability of the bunds and reduce maintenance cost. Economic feasibility analysis also showed that, soil and water conservation practices became economically more viable if physical and agronomic soil and water conservation practices are integrated.

  7. Impacts of Soil and Water Conservation Practices on Crop Yield, Run-off, Soil Loss and Nutrient Loss in Ethiopia: Review and Synthesis

    NASA Astrophysics Data System (ADS)

    Adimassu, Zenebe; Langan, Simon; Johnston, Robyn; Mekuria, Wolde; Amede, Tilahun

    2017-01-01

    Research results published regarding the impact of soil and water conservation practices in the highland areas of Ethiopia have been inconsistent and scattered. In this paper, a detailed review and synthesis is reported that was conducted to identify the impacts of soil and water conservation practices on crop yield, surface run-off, soil loss, nutrient loss, and the economic viability, as well as to discuss the implications for an integrated approach and ecosystem services. The review and synthesis showed that most physical soil and water conservation practices such as soil bunds and stone bunds were very effective in reducing run-off, soil erosion and nutrient depletion. Despite these positive impacts on these services, the impact of physical soil and water conservation practices on crop yield was negative mainly due to the reduction of effective cultivable area by soil/stone bunds. In contrast, most agronomic soil and water conservation practices increase crop yield and reduce run-off and soil losses. This implies that integrating physical soil and water conservation practices with agronomic soil and water conservation practices are essential to increase both provisioning and regulating ecosystem services. Additionally, effective use of unutilized land (the area occupied by bunds) by planting multipurpose grasses and trees on the bunds may offset the yield lost due to a reduction in planting area. If high value grasses and trees can be grown on this land, farmers can harvest fodder for animals or fuel wood, both in scarce supply in Ethiopia. Growing of these grasses and trees can also help the stability of the bunds and reduce maintenance cost. Economic feasibility analysis also showed that, soil and water conservation practices became economically more viable if physical and agronomic soil and water conservation practices are integrated.

  8. Sedimentation History of Lago Dos Bocas, Puerto Rico, 1942-2005

    USGS Publications Warehouse

    Soler-López, Luis R.

    2007-01-01

    The Lago Dos Bocas Dam, located in the municipality of Utuado in north central Puerto Rico, was constructed in 1942 for hydroelectric power generation. The reservoir had an original storage capacity of 37.50 million cubic meters and a drainage area of 440 square kilometers. In 1948, the construction of the Lago Caonillas Dam on the Rio Caonillas branch of Lago Dos Bocas reduced the natural sediment-contributing drainage area to 310 square kilometers; therefore, the Lago Caonillas Dam is considered an effective sediment trap. Sedimentation in Lago Dos Bocas reservoir has reduced the storage capacity from 37.50 million cubic meters in 1942 to 17.26 million cubic meters in 2005, which represents a storage loss of about 54 percent. The long-term annual water-storage capacity loss rate remained nearly constant at about 320,000 cubic meters per year to about 1997. The inter-survey sedimentation rate between 1997 and 1999, however, is higher than the long-term rate at about 1.09 million cubic meters per year. Between 1999 and 2005 the rate is lower than the long-term rate at about 0.13 million cubic meters per year. The Lago Dos Bocas effective sediment-contributing drainage area had an average sediment yield of about 1,400 cubic meters per square kilometer per year between 1942 and 1997. This rate increased substantially by 1999 to about 4,600 cubic meters per square kilometer per year, probably resulting from the historical magnitude floods caused by Hurricane Georges in 1998. Recent data indicate that the Lago Dos Bocas drainage area sediment yield decreased substantially to about 570 cubic meters per square kilometer per year, which is much lower than the 1942-1997 area normalized sedimentation rate of 1,235 cubic meters per square kilometer per year. The impact of Hurricane Georges on the basin sediment yield could have been the cause of this change, since the magnitude of the floods could have nearly depleted the Lago Dos Bocas drainage area of easily erodible and transportable bed sediment. This report summarizes the historical change in water-storage capacity of Lago Dos Bocas between 1942 and 2005.

  9. Impact of intermediate and high energy nuclear data on the neutronic safety parameters of MYRRHA accelerator driven system

    NASA Astrophysics Data System (ADS)

    Stankovskiy, Alexey; Çelik, Yurdunaz; Eynde, Gert Van den

    2017-09-01

    Perturbation of external neutron source can cause significant local power changes transformed into undesired safety-related events in an accelerator driven system. Therefore for the accurate design of MYRRHA sub-critical core it is important to evaluate the uncertainty of power responses caused by the uncertainties in nuclear reaction models describing the particle transport from primary proton energy down to the evaluated nuclear data table range. The calculations with a set of models resulted in quite low uncertainty on the local power caused by significant perturbation of primary neutron yield from proton interactions with lead and bismuth isotopes. The considered accidental event of prescribed proton beam shape loss causes drastic increase in local power but does not practically change the total core thermal power making this effect difficult to detect. In the same time the results demonstrate a correlation between perturbed local power responses in normal operation and misaligned beam conditions indicating that generation of covariance data for proton and neutron induced neutron multiplicities for lead and bismuth isotopes is needed to obtain reliable uncertainties for local power responses.

  10. Nitrogen losses and greenhouse gas emissions under different N and water management in a subtropical double-season rice cropping system.

    PubMed

    Liang, Kaiming; Zhong, Xuhua; Huang, Nongrong; Lampayan, Rubenito M; Liu, Yanzhuo; Pan, Junfeng; Peng, Bilin; Hu, Xiangyu; Fu, Youqiang

    2017-12-31

    Nitrogen non-point pollution and greenhouse gas (GHG) emission are major challenges in rice production. This study examined options for both economic and environmental sustainability through optimizing water and N management. Field experiments were conducted to examine the crop yields, N use efficiency (NUE), greenhouse gas emissions, N losses under different N and water management. There were four treatments: zero N input with farmer's water management (N0), farmer's N and water management (FP), optimized N management with farmer's water management (OPT N ) and optimized N management with alternate wetting and drying irrigation (OPT N +AWD). Grain yields in OPT N and OPT N +AWD treatments increased by 13.0-17.3% compared with FP. Ammonia volatilization (AV) was the primary pathway for N loss for all treatments and accounted for over 50% of the total losses. N losses mainly occurred before mid-tillering. N losses through AV, leaching and surface runoff in OPT N were reduced by 18.9-51.6% compared with FP. OPT N +AWD further reduced N losses from surface runoff and leaching by 39.1% and 6.2% in early rice season, and by 46.7% and 23.5% in late rice season, respectively, compared with OPT N . The CH 4 emissions in OPT N +AWD were 20.4-45.4% lower than in OPT N and FP. Total global warming potential of CH 4 and N 2 O was the lowest in OPT N +AWD. On-farm comparison confirmed that N loss through runoff in OPT N +AWD was reduced by over 40% as compared with FP. OPT N and OPT N +AWD significantly increased grain yield by 6.7-13.9%. These results indicated that optimizing water and N management can be a simple and effective approach for enhancing yield with reduced environmental footprints. Copyright © 2017. Published by Elsevier B.V.

  11. Effects of ageing on the hydraulics of water wells and the influence of non-Darcy flow

    NASA Astrophysics Data System (ADS)

    Houben, Georg J.; Wachenhausen, Julia; Guevara Morel, Carlos R.

    2018-04-01

    Well ageing is mostly caused by mechanical and biogeochemical clogging processes, which affect the gravel pack, screen slots and casing. Clogging deposits increase head losses due to a constriction of the hydraulically effective area. For this study, clogging is mimicked by systematically reducing the gravel pack porosity, the screen open area and the nominal inner casing diameter. Groundwater flow velocity strongly increases close to the well, inducing inertial and turbulent flow components. Therefore, gravel pack head losses were calculated using the Forchheimer-Engelund equation, in conjunction with the Kozeny-Carman equation, which relates gravel pack porosity and hydraulic conductivity. Screen losses were assessed using the Orifice equation and turbulent casing losses with the Darcy-Weisbach equation. For the settings chosen here, a dramatic increase of head losses occurs when the clogging has reduced the effective porosity in the gravel pack by 65%, the open area of the screen by ≥98%, and the casing diameter by 50%. Since the latter two conditions are rarely reached in actual wells, the clogging of the gravel pack is the decisive parameter that controls well ageing. Regular monitoring of the well yield is therefore needed, since processes in the gravel pack are difficult to track directly. Unlike the deposits on the casing and in the screen slots, obstructions in the gravel pack are much more difficult to remove.

  12. Effects of ageing on the hydraulics of water wells and the influence of non-Darcy flow

    NASA Astrophysics Data System (ADS)

    Houben, Georg J.; Wachenhausen, Julia; Guevara Morel, Carlos R.

    2018-06-01

    Well ageing is mostly caused by mechanical and biogeochemical clogging processes, which affect the gravel pack, screen slots and casing. Clogging deposits increase head losses due to a constriction of the hydraulically effective area. For this study, clogging is mimicked by systematically reducing the gravel pack porosity, the screen open area and the nominal inner casing diameter. Groundwater flow velocity strongly increases close to the well, inducing inertial and turbulent flow components. Therefore, gravel pack head losses were calculated using the Forchheimer-Engelund equation, in conjunction with the Kozeny-Carman equation, which relates gravel pack porosity and hydraulic conductivity. Screen losses were assessed using the Orifice equation and turbulent casing losses with the Darcy-Weisbach equation. For the settings chosen here, a dramatic increase of head losses occurs when the clogging has reduced the effective porosity in the gravel pack by 65%, the open area of the screen by ≥98%, and the casing diameter by 50%. Since the latter two conditions are rarely reached in actual wells, the clogging of the gravel pack is the decisive parameter that controls well ageing. Regular monitoring of the well yield is therefore needed, since processes in the gravel pack are difficult to track directly. Unlike the deposits on the casing and in the screen slots, obstructions in the gravel pack are much more difficult to remove.

  13. Chilli Anthracnose: The Epidemiology and Management.

    PubMed

    Saxena, Amrita; Raghuwanshi, Richa; Gupta, Vijai Kumar; Singh, Harikesh B

    2016-01-01

    Indian cuisine is renowned and celebrated throughout the world for its spicy treat to the tongue. The flavor and aroma of the food generated due to the use of spices creates an indelible experience. Among the commonly utilized spices to stimulate the taste buds in Indian food, whole or powdered chilli constitutes an inevitable position. Besides being a vital ingredient of of Indian food, chilli occupy an important position as an economic commodity, a major share in Indian economy. Chilli also has uncountable benefits to human health. Fresh green chilli fruits contain more Vitamin C than found in citrus fruits, while red chilli fruits have more Vitamin A content than as found in carrots. The active component of the spice, Capsaicin possesses the antioxidant, anti-mutagenic, anti-carcinogenic and immunosuppressive activities having ability to inhibit bacterial growth and platelet aggregation. Though introduced by the Portuguese in the Seventeenth century, India has been one of the major producers and exporters of this crop. During 2010-2011, India was the leading exporter and producer of chilli in the world, but recently due to a decline in chilli production, it stands at third position in terms of its production. The decline in chilli production has been attributed to the diseases linked with crop like anthracnose or fruit rot causing the major share of crop loss. The disease causes severe damage to both mature fruits in the field as well as during their storage under favorable conditions, which amplifies the loss in yield and overall production of the crop. This review gives an account of the loss in production and yield procured in chili cultivation due to anthracnose disease in Indian sub-continent, with emphasis given to the sustainable management strategies against the conventionally recommended control for the disease. Also, the review highlights the various pathogenic species of Colletotrichum spp, the causal agent of the disease, associated with the host crop in the country. The information in the review will prove of immense importance for the groups targeting the problem, for giving a collective information on various aspects of the epidemiology and management of the disease.

  14. Peripartum dynamics of Coxiella burnetii infections in intensively managed dairy goats associated with a Q fever outbreak in Australia.

    PubMed

    Muleme, Michael; Stenos, John; Vincent, Gemma; Wilks, Colin R; Devlin, Joanne M; Campbell, Angus; Cameron, Alexander; Stevenson, Mark A; Graves, Stephen; Firestone, Simon M

    2017-04-01

    Coxiella burnetii may cause reproduction disorders in pregnant animals but subclinical infection in other animals. Unrecognised disease may delay implementation of control interventions, resulting in transmission of infection to other livestock and to humans. Seroreactivity to C. burnetii phase-specific antigens, is routinely used to interpret the course of human Q fever. This approach could be similarly useful in identifying new and existing infections in livestock herds to help describe risk factors or production losses associated with the infections and the implementation of disease-control interventions. This study aimed to elucidate the dynamics of C. burnetii infections using seroreactivity to phase-specific antigens and to examine the impact of infection on milk yield in goats in an endemically-infected farm that was associated with a Q fever outbreak in Australia. Seroreactivity pre- and post-partum and milk yield were studied in 164 goats (86 nulliparous and 78 parous). Post-partum, the seroprevalence of antibodies to C. burnetti increased from 4.7% to 31.4% throughout goats' first kiddings and from 47.4% to 55.1% in goats kidding for the second or greater time. Of 123 goats that were seronegative pre-partum, 26.8% seroconverted over the three-month peri-partum period, highlighting the importance of controlling infection throughout this time. The risk of seroconversion was comparable in first or later kidders, suggesting constant risk irrespective of parity. No loss in milk production associated with seroconversion to phase 2 was observed within the first nine weeks of lactation. However, seroconversion to only phase 1 was associated with extra 0.276L of milk per day (95% Confidence Interval: 0.010, 0.543; P=0.042), which warrants further investigation to ascertain whether or not the association is causal. Further studies on seroreactivity and milk production over longer periods are required, as milk production loss caused by C. burnetti may be an additional reason to control the disease in goat herds. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Chilli Anthracnose: The Epidemiology and Management

    PubMed Central

    Saxena, Amrita; Raghuwanshi, Richa; Gupta, Vijai Kumar; Singh, Harikesh B.

    2016-01-01

    Indian cuisine is renowned and celebrated throughout the world for its spicy treat to the tongue. The flavor and aroma of the food generated due to the use of spices creates an indelible experience. Among the commonly utilized spices to stimulate the taste buds in Indian food, whole or powdered chilli constitutes an inevitable position. Besides being a vital ingredient of of Indian food, chilli occupy an important position as an economic commodity, a major share in Indian economy. Chilli also has uncountable benefits to human health. Fresh green chilli fruits contain more Vitamin C than found in citrus fruits, while red chilli fruits have more Vitamin A content than as found in carrots. The active component of the spice, Capsaicin possesses the antioxidant, anti-mutagenic, anti-carcinogenic and immunosuppressive activities having ability to inhibit bacterial growth and platelet aggregation. Though introduced by the Portuguese in the Seventeenth century, India has been one of the major producers and exporters of this crop. During 2010–2011, India was the leading exporter and producer of chilli in the world, but recently due to a decline in chilli production, it stands at third position in terms of its production. The decline in chilli production has been attributed to the diseases linked with crop like anthracnose or fruit rot causing the major share of crop loss. The disease causes severe damage to both mature fruits in the field as well as during their storage under favorable conditions, which amplifies the loss in yield and overall production of the crop. This review gives an account of the loss in production and yield procured in chili cultivation due to anthracnose disease in Indian sub-continent, with emphasis given to the sustainable management strategies against the conventionally recommended control for the disease. Also, the review highlights the various pathogenic species of Colletotrichum spp, the causal agent of the disease, associated with the host crop in the country. The information in the review will prove of immense importance for the groups targeting the problem, for giving a collective information on various aspects of the epidemiology and management of the disease. PMID:27746765

  16. Plausible rice yield losses under future climate warming.

    PubMed

    Zhao, Chuang; Piao, Shilong; Wang, Xuhui; Huang, Yao; Ciais, Philippe; Elliott, Joshua; Huang, Mengtian; Janssens, Ivan A; Li, Tao; Lian, Xu; Liu, Yongwen; Müller, Christoph; Peng, Shushi; Wang, Tao; Zeng, Zhenzhong; Peñuelas, Josep

    2016-12-19

    Rice is the staple food for more than 50% of the world's population 1-3 . Reliable prediction of changes in rice yield is thus central for maintaining global food security. This is an extraordinary challenge. Here, we compare the sensitivity of rice yield to temperature increase derived from field warming experiments and three modelling approaches: statistical models, local crop models and global gridded crop models. Field warming experiments produce a substantial rice yield loss under warming, with an average temperature sensitivity of -5.2 ± 1.4% K -1 . Local crop models give a similar sensitivity (-6.3 ± 0.4% K -1 ), but statistical and global gridded crop models both suggest less negative impacts of warming on yields (-0.8 ± 0.3% and -2.4 ± 3.7% K -1 , respectively). Using data from field warming experiments, we further propose a conditional probability approach to constrain the large range of global gridded crop model results for the future yield changes in response to warming by the end of the century (from -1.3% to -9.3% K -1 ). The constraint implies a more negative response to warming (-8.3 ± 1.4% K -1 ) and reduces the spread of the model ensemble by 33%. This yield reduction exceeds that estimated by the International Food Policy Research Institute assessment (-4.2 to -6.4% K -1 ) (ref. 4). Our study suggests that without CO 2 fertilization, effective adaptation and genetic improvement, severe rice yield losses are plausible under intensive climate warming scenarios.

  17. Postpartum body condition score and results from the first test day milk as predictors of disease, fertility, yield, and culling in commercial dairy herds.

    PubMed

    Heuer, C; Schukken, Y H; Dobbelaar, P

    1999-02-01

    The study used field data from a regular herd health service to investigate the relationships between body condition scores or first test day milk data and disease incidence, milk yield, fertility, and culling. Path model analysis with adjustment for time at risk was applied to delineate the time sequence of events. Milk fever occurred more often in fat cows, and endometritis occurred between calving and 20 d of lactation more often in thin cows. Fat cows were less likely to conceive at first service than were cows in normal condition. Fat body condition postpartum, higher first test day milk yield, and a fat to protein ratio of > 1.5 increased body condition loss. Fat or thin condition or condition loss was not related to other lactation diseases, fertility parameters, milk yield, or culling. First test day milk yield was 1.3 kg higher after milk fever and was 7.1 kg lower after displaced abomasum. Higher first test day milk yield directly increased the risk of ovarian cyst and lameness, increased 100-d milk yield, and reduced the risk of culling and indirectly decreased reproductive performance. Cows with a fat to protein ratio of > 1.5 had higher risks for ketosis, displaced abomasum, ovarian cyst, lameness, and mastitis. Those cows produced more milk but showed poor reproductive performance. Given this type of herd health data, we concluded that the first test day milk yield and the fat to protein ratio were more reliable indicators of disease, fertility, and milk yield than was body condition score or loss of body condition score.

  18. Cereal area and nitrogen use efficiency are drivers of future nitrogen fertilizer consumption.

    PubMed

    Dobermann, Achim; Cassman, Kenneth G

    2005-09-01

    At a global scale, cereal yields and fertilizer N consumption have increased in a near-linear fashion during the past 40 years and are highly correlated with one another. However, large differences exist in historical trends of N fertilizer usage and nitrogen use efficiency (NUE) among regions, countries, and crops. The reasons for these differences must be understood to estimate future N fertilizer requirements. Global nitrogen needs will depend on: (i) changes in cropped cereal area and the associated yield increases required to meet increasing cereal demand from population and income growth, and (ii) changes in NUE at the farm level. Our analysis indicates that the anticipated 38% increase in global cereal demand by 2025 can be met by a 30% increase in N use on cereals, provided that the steady decline in cereal harvest area is halted and the yield response to applied N can be increased by 20%. If losses of cereal cropping area continue at the rate of the past 20 years (-0.33% per year) and NUE cannot be increased substantially, a 60% increase in global N use on cereals would be required to meet cereal demand. Interventions to increase NUE and reduce N losses to the environment must be accomplished at the farm-or field-scale through a combination of improved technologies and carefully crafted local policies that contribute to the adoption of improved N management; uniform regional or national directives are unlikely to be effective at both sustaining yield increases and improving NUE. Examples from several countries show that increases in NUE at rates of 1% per year or more can be achieved if adequate investments are made in research and extension. Failure to arrest the decrease in cereal crop area and to improve NUE in the world's most important agricultural systems will likely cause severe damage to environmental services at local, regional, and global scales due to a large increase in reactive N load in the environment.

  19. Tripartite Interactions of Barley Yellow Dwarf Virus, Sitobion avenae and Wheat Varieties

    PubMed Central

    Liu, Xiao-Feng; Hu, Xiang-Shun; Keller, Mike A.; Zhao, Hui-Yan; Wu, Yun-Feng; Liu, Tong-Xian

    2014-01-01

    The tripartite interactions in a pathosystem involving wheat (Triticum aestivum L.), the Barley yellow dwarf virus (BYDV), and the BYDV vector aphid Sitobion avenae were studied under field conditions to determine the impact of these interactions on aphid populations, virus pathology and grain yield. Wheat varietal resistance to BYDV and aphids varied among the three wheat varieties studied over two consecutive years. The results demonstrated that (1) aphid peak number (APN) in the aphid + BYDV (viruliferous aphid) treatment was greater and occurred earlier than that in the non-viruliferous aphid treatment. The APN and the area under the curve of population dynamics (AUC) on a S. avenae-resistant variety 98-10-30 was significantly lower than on two aphid-susceptible varieties Tam200(13)G and Xiaoyan6. (2) The production of alatae (PA) was greater on the variety 98-10-30 than on the other varieties, and PA was greater in the aphid + BYDV treatment on 98-10-30 than in the non-viruliferous aphid treatment, but this trend was reversed on Tam200(13)G and Xiaoyan6. (3) The BYDV disease incidence (DIC) on the variety 98-10-30 was greater than that on the other two varieties in 2012, and the disease index (DID) on Tam200(13)G was lower than on the other varieties in the aphid + BYDV and BYDV treatments in 2012, but not in 2011 when aphid vector numbers were generally lower. (4) Yield loss in the aphid + BYDV treatment tended to be greater than that in the aphid or BYDV alone treatments across varieties and years. We suggested that aphid population development and BYDV transmission tend to promote each other under field conditions. The aphids + BYDV treatment caused greater yield reductions than non-viruliferous aphids or virus treatment. Wheat varietal resistance in 98-10-30 affects the aphid dispersal, virus transmission and wheat yield loss though inhibits aphid populations from increasing. PMID:25184214

  20. Reducing sugar production of sweet sorghum bagasse kraft pulp

    NASA Astrophysics Data System (ADS)

    Solihat, Nissa Nurfajrin; Fajriutami, Triyani; Adi, Deddy Triyono Nugroho; Fatriasari, Widya; Hermiati, Euis

    2017-01-01

    Kraft pulping of sweet sorghum bagasse (SSB) has been used for effective delignification method for cellulose production. This study was conducted to evaluate the performance pulp kraft of SSB for reducing sugar production. The study intended to investigate the effect of active alkali and sulfidity loading variation of SSB pulp kraft on reducing sugar yield per biomass. The SSB pulp was prepared after pulping using three variations of active alkali (17, 19, and 22%) and sulfidity loading (20, 22, and 24%) at 170°C for 4 h with liquor to wood ratio of 10. A total of 9 pulps were obtained from these pretreatments. Delignification pretreatment has been succesfully removed lignin and hemicellulose more than 90% and 50%, respectively. Increasing active alkali and sulfidity loading has significantly increased lignin removal caused by disruption of the cell wall structure for releasing lignin into black liquor in the cellulose extraction. The enzymatic hydrolysis of pulp was carried out with cellulase loading of 40 FPU per g substrate in the shaking incubator at 50°C and 150 rpm for 78 h. For each 24 h, the reducing sugar yield (DNS assay) has been observed. Even though the lignin and hemicellulose loss occurred along with higher active alkali loading, this condition tends to decrease its yield. The reducing sugar concentration varied between 7-8 g/L. Increasing active alkali and sulfidity was significantly decreased the reducing sugar per biomass. Pulp delignified by 17% active alkali and 20% sulfidity has demonstrated the maximum reducing sugar yield per biomass of 45.57% resulted after 72 h enzymatic hydrolysis. These results indicated that kraft pulping was success to degrade more lignin and hemicellulose content to facilitate the enzyme for breaking down the cellulose into its sugar monomer. A high loss of lignin and hemicellulose are not single factor to improve digestibility of SSB. This sugar has potential for yeast fermented into bioethanol.

  1. The combined and separate impacts of climate extremes on the current and future US rainfed maize and soybean production under elevated CO2.

    PubMed

    Jin, Zhenong; Zhuang, Qianlai; Wang, Jiali; Archontoulis, Sotirios V; Zobel, Zachary; Kotamarthi, Veerabhadra R

    2017-07-01

    Heat and drought are two emerging climatic threats to the US maize and soybean production, yet their impacts on yields are collectively determined by the magnitude of climate change and rising atmospheric CO 2 concentrations. This study quantifies the combined and separate impacts of high temperature, heat and drought stresses on the current and future US rainfed maize and soybean production and for the first time characterizes spatial shifts in the relative importance of individual stress. Crop yields are simulated using the Agricultural Production Systems Simulator (APSIM), driven by high-resolution (12 km) dynamically downscaled climate projections for 1995-2004 and 2085-2094. Results show that maize and soybean yield losses are prominent in the US Midwest by the late 21st century under both Representative Concentration Pathway (RCP) 4.5 and RCP8.5 scenarios, and the magnitude of loss highly depends on the current vulnerability and changes in climate extremes. Elevated atmospheric CO 2 partially but not completely offsets the yield gaps caused by climate extremes, and the effect is greater in soybean than in maize. Our simulations suggest that drought will continue to be the largest threat to US rainfed maize production under RCP4.5 and soybean production under both RCP scenarios, whereas high temperature and heat stress take over the dominant stress of drought on maize under RCP8.5. We also reveal that shifts in the geographic distributions of dominant stresses are characterized by the increase in concurrent stresses, especially for the US Midwest. These findings imply the importance of considering heat and drought stresses simultaneously for future agronomic adaptation and mitigation strategies, particularly for breeding programs and crop management. The modeling framework of partitioning the total effects of climate change into individual stress impacts can be applied to the study of other crops and agriculture systems. © 2017 John Wiley & Sons Ltd.

  2. Cereal area and nitrogen use efficiency are drivers of future nitrogen fertilizer consumption.

    PubMed

    Dobermann, Achim; Cassman, Kenneth G

    2005-12-01

    At a global scale, cereal yields and fertilizer N consumption have increased in a near-linear fashion during the past 40 years and are highly correlated with one another. However, large differences exist in historical trends of N fertilizer usage and nitrogen use efficiency (NUE) among regions, countries, and crops. The reasons for these differences must be understood to estimate future N fertilizer requirements. Global nitrogen needs will depend on: (i) changes in cropped cereal area and the associated yield increases required to meet increasing cereal demand from population and income growth, and (ii) changes in NUE at the farm level. Our analysis indicates that the anticipated 38% increase in global cereal demand by 2025 can be met by a 30% increase in N use on cereals, provided that the steady decline in cereal harvest area is halted and the yield response to applied N can be increased by 20%. If losses of cereal cropping area continue at the rate of the past 20 years (-0.33% per year) and NUE cannot be increased substantially, a 60% increase in global N use on cereals would be required to meet cereal demand. Interventions to increase NUE and reduce N losses to the environment must be accomplished at the farm- or field-scale through a combination of improved technologies and carefully crafted local policies that contribute to the adoption of improved N management; uniform regional or national directives are unlikey to be effective at both sustaining yield increases and improving NUE. Examples from several countries show that increases in NUE at rates of 1% per year or more can be achieved if adequate investments are made in research and extension. Failure to arrest the decrease in cereal crop area and to improve NUE in the world's most important agricultural systems will likely cause severe damage to environmental services at local, regional, and global scales due to a large increase in reactive N load in the environment.

  3. The MUC4 membrane-bound mucin regulates esophageal cancer cell proliferation and migration properties: Implication for S100A4 protein

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

    Bruyere, Emilie; Jonckheere, Nicolas; Frenois, Frederic

    2011-09-23

    Highlights: {yields} Loss of MUC4 reduces proliferation of esophageal cancer cells. {yields} MUC4 inhibition impairs migration of esophageal cancer cells but not their invasion. {yields} Loss of MUC4 significantly reduces in vivo tumor growth. {yields} Decrease of S100A4 induced by MUC4 inhibition impairs proliferation and migration. -- Abstract: MUC4 is a membrane-bound mucin known to participate in tumor progression. It has been shown that MUC4 pattern of expression is modified during esophageal carcinogenesis, with a progressive increase from metaplastic lesions to adenocarcinoma. The principal cause of development of esophageal adenocarcinoma is the gastro-esophageal reflux, and MUC4 was previously shown tomore » be upregulated by several bile acids present in reflux. In this report, our aim was thus to determine whether MUC4 plays a role in biological properties of human esophageal cancer cells. For that stable MUC4-deficient cancer cell lines (shMUC4 cells) were established using a shRNA approach. In vitro (proliferation, migration and invasion) and in vivo (tumor growth following subcutaneous xenografts in SCID mice) biological properties of shMUC4 cells were analyzed. Our results show that shMUC4 cells were less proliferative, had decreased migration properties and did not express S100A4 protein when compared with MUC4 expressing cells. Absence of MUC4 did not impair shMUC4 invasiveness. Subcutaneous xenografts showed a significant decrease in tumor size when cells did not express MUC4. Altogether, these data indicate that MUC4 plays a key role in proliferative and migrating properties of esophageal cancer cells as well as is a tumor growth promoter. MUC4 mucin appears thus as a good therapeutic target to slow-down esophageal tumor progression.« less

  4. Current ambient ozone in China has threatened the health of farmland ecosystem

    NASA Astrophysics Data System (ADS)

    Feng, Z.

    2017-12-01

    Ground-level Ozone (O3) has been one of global environmental issues as a result of rising concentration at most parts of the earth causing significant biological and economic damage to both agricultural and native species. Although the rising trends in O3 concentration have leveled off or decreased slightly in North America and Europe, the trends are increasing in developing countries such as India and China. Here, the impacts of ozone on crops in China are reviewed from studies during the last two decades. The field experimental methods include open-top chambers (OTC), free-air concentration enrichments (FACE) and chemical protectant EDU application. The experimental crops are winter wheat, rice, soybean, and oilrape. At a regional scale, yield loss in Yangtze River Delta by O3 was estimated to be 17%, 3% and 6% for wheat, rice and oil rape, respectively, and the corresponding economic losses were estimated to be 86 M US , 116 M US and 39 M US $ at the rate of 2007 (Yao et al., 2008). In four years' FACE studies, a mean 25% enhancement above the ambient O3 concentration significantly reduced the grain yield by, on average, 20% and 12% for winter wheat and rice, respectively, but there were significant differences in O3 sensitivity among the cultivars studied (Shi et al., 2009; Zhu et al., 2011). Both flux and concentration -based dose-response relationships indicated that FACE system induced larger yield loss of crops than OTCs, suggesting that O3 effects on crop yield were underestimated. Therefore, it can be inferred that food security will be seriously threatened by rising O3 concentration due to the intensive rate of urbanization in China. However, the impacts of O3 on local food crops need to be investigated more thoroughly in different parts of China, and the combined effects of elevated O3 and other factors like warming and CO2 should be considered. ReferencesFeng, Z. Z., Tang, H.Y., Uddling, J, et al. (2012). Environ Pollut, 164, 16-23. Shi, G.Y., Yang, L.X., Wang, Y.X., et al. (2009). Agr, Ecosyst Environ, 131, 178-184. Yao, F.F., Wang, X.K., Lu, F., et al. (2008). Asian J. Ecotoxicology, 189-195. Zhu, X.K., Feng, Z.Z., Sun, T.F., et al. (2011). Global Change Biol, 17, 2697-2706.

  5. Degradation Mechanisms in Blue Phosphorescent Organic Light-Emitting Devices by Exciton-Polaron Interactions: Loss in Quantum Yield versus Loss in Charge Balance.

    PubMed

    Zhang, Yingjie; Aziz, Hany

    2017-01-11

    We study the relative importance of deterioration of material quantum yield and charge balance to the electroluminescence stability of PHOLEDs, with a special emphasis on blue devices. Investigations show that the quantum yields of both host and emitter in the emission layer degrade due to exciton-polaron interactions and that the deterioration in material quantum yield plays the primary role in device degradation under operation. On the other hand, the results show that the charge balance factor is also affected by exciton-polaron interactions but only plays a secondary role in determining device stability. Finally, we show that the degradation mechanisms in blue PHOLEDs are fundamentally the same as those in green PHOLEDs. The limited stability of the blue devices is a result of faster deterioration in the quantum yield of the emitter.

  6. Evidence for a weakening strength of temperature-corn yield relation in the United States during 1980–2010

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

    Leng, Guoyong

    Temperature is known to be correlated with crop yields, causing reduction of crop yield with climate warming without adaptations or CO2 fertilization effects. The historical temperature-crop yield relation has often been used for informing future changes. This relationship, however, may change over time following alternations in other environmental factors. Results show that the strength of the relationship between the interannual variability of growing season temperature and corn yield (RGST_CY) has declined in the United States between 1980 and 2010 with a loss in the statistical significance. The regression slope which represents the anomalies in corn yield that occur in associationmore » with 1 degree temperature anomaly has decreased significantly from -6.9%/K of the first half period to -2.4%/K~-3.5%/K of the second half period. This implies that projected corn yield reduction will be overestimated by a fact of 2 in a given warming scenario, if the corn-temperature relation is derived from the earlier historical period. Changes in RGST_CY are mainly observed in Midwest Corn Belt and central High Plains, and are well reproduced by 11 process-based crop models. In Midwest rain-fed systems, the decrease of negative temperature effects coincides with an increase in water availability by precipitation. In irrigated areas where water stress is minimized, the decline of beneficial temperature effects is significantly related to the increase in extreme hot days. The results indicate that an extrapolation of historical yield response to temperature may bias the assessment of agriculture vulnerability to climate change. Efforts to reduce climate impacts on agriculture should pay attention not only to climate change, but also to changes in climate-crop yield relations. There are some caveats that should be acknowledged as the analysis is restricted to the changes in the linear relation between growing season mean temperature and corn yield for the specific study period.« less

  7. Evidence for a weakening strength of temperature-corn yield relation in the United States during 1980-2010.

    PubMed

    Leng, Guoyong

    2017-12-15

    Temperature is known to be correlated with crop yields, causing reduction of crop yield with climate warming without adaptations or CO 2 fertilization effects. The historical temperature-crop yield relation has often been used for informing future changes. This relationship, however, may change over time following alternations in other environmental factors. Results show that the strength of the relationship between the interannual variability of growing season temperature and corn yield (R GST_CY ) has declined in the United States between 1980 and 2010 with a loss in the statistical significance. The regression slope which represents the anomalies in corn yield that occur in association with 1 degree temperature anomaly has decreased significantly from -6.9%/K of the first half period to -2.4%/K--3.5%/K of the second half period. This implies that projected corn yield reduction will be overestimated by a fact of 2 in a given warming scenario, if the corn-temperature relation is derived from the earlier historical period. Changes in R GST_CY are mainly observed in Midwest Corn Belt and central High Plains, but are partly reproduced by 11 process-based crop models. In Midwest rain-fed systems, the decrease of negative temperature effects coincides with an increase in water availability by precipitation. In irrigated areas where water stress is minimized, the decline of beneficial temperature effects is significantly related to the increase in extreme hot days. The results indicate that an extrapolation of historical yield response to temperature may bias the assessment of agriculture vulnerability to climate change. Efforts to reduce climate impacts on agriculture should pay attention not only to climate change, but also to changes in climate-crop yield relations. There are some caveats that should be acknowledged as the analysis is restricted to the changes in the linear relation between growing season mean temperature and corn yield for the specific study period. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Development of a Coupled Hydrological/Sediment Yield Model for a Watershed at Regional Level

    NASA Technical Reports Server (NTRS)

    Rajbhandaril, Narayan; Crosson, William; Tsegaye, Teferi; Coleman, Tommy; Liu, Yaping; Soman, Vishwas

    1998-01-01

    Development of a hydrologic model for the study of environmental conservation requires a comprehensive understanding of individual-storm affecting hydrologic and sedimentologic processes. The hydrologic models that we are currently coupling are the Simulator for Hydrology and Energy Exchange at the Land Surface (SHEELS) and the Distributed Runoff Model (DRUM). SHEELS runs continuously to estimate surface energy fluxes and sub-surface soil water fluxes, while DRUM operates during and following precipitation events to predict surface runoff and peak flow through channel routing. The lateral re-distribution of surface water determined by DRUM is passed to SHEELS, which then adjusts soil water contents throughout the profile. The model SHEELS is well documented in Smith et al. (1993) and Laymen and Crosson (1995). The model DRUM is well documented in Vieux et al. (1990) and Vieux and Gauer (1994). The coupled hydrologic model, SHEELS/DRUM, does not simulate sedimentologic processes. The simulation of the sedimentologic process is important for environmental conservation planning and management. Therefore, we attempted to develop a conceptual frame work for coupling a sediment yield model with SHEELS/DRUM to estimate individual-storm sediment yield from a watershed at a regional level. The sediment yield model that will be used for this study is the Universal Soil Loss Equation (USLE) with some modifications to enable the model to predict individual-storm sediment yield. The predicted sediment yield does not include wind erosion and erosion caused by irrigation and snow melt. Units used for this study are those given by Foster et al. (1981) for SI units.

  9. Multistate outbreak of listeriosis caused by imported cheese and evidence of cross-contamination of other cheeses, USA, 2012.

    PubMed

    Heiman, K E; Garalde, V B; Gronostaj, M; Jackson, K A; Beam, S; Joseph, L; Saupe, A; Ricotta, E; Waechter, H; Wellman, A; Adams-Cameron, M; Ray, G; Fields, A; Chen, Y; Datta, A; Burall, L; Sabol, A; Kucerova, Z; Trees, E; Metz, M; Leblanc, P; Lance, S; Griffin, P M; Tauxe, R V; Silk, B J

    2016-10-01

    Listeria monocytogenes is a foodborne pathogen that can cause bacteraemia, meningitis, and complications during pregnancy. In July 2012, molecular subtyping identified indistinguishable L. monocytogenes isolates from six patients and two samples of different cut and repackaged cheeses. A multistate outbreak investigation was initiated. Initial analyses identified an association between eating soft cheese and outbreak-related illness (odds ratio 17·3, 95% confidence interval 2·0-825·7) but no common brand. Cheese inventory data from locations where patients bought cheese and an additional location where repackaged cheese yielded the outbreak strain were compared to identify cheeses for microbiological sampling. Intact packages of imported ricotta salata yielded the outbreak strain. Fourteen jurisdictions reported 22 cases from March-October 2012, including four deaths and a fetal loss. Six patients ultimately reported eating ricotta salata; another reported eating cheese likely cut with equipment also used for contaminated ricotta salata, and nine more reported eating other cheeses that might also have been cross-contaminated. An FDA import alert and US and international recalls followed. Epidemiology-directed microbiological testing of suspect cheeses helped identify the outbreak source. Cross-contamination of cheese highlights the importance of using validated disinfectant protocols and routine cleaning and sanitizing after cutting each block or wheel.

  10. Liquid culture production of microsclerotia and submerged conidia by Trichoderma harzianum active against damping-off disease caused by Rhizoctonia solani.

    PubMed

    Kobori, Nilce N; Mascarin, Gabriel M; Jackson, Mark A; Schisler, David A

    2015-04-01

    Media and culturing protocols were identified that supported the formation of submerged conidia and microsclerotia (MS) by Trichoderma harzianum Rifai strain T-22 using liquid culture fermentation. Liquid media with a higher carbon concentration (36 g L(-1)) promoted MS formation at all C:N ratios tested. Hyphae aggregated to form MS after 2 d growth and after 7 d MS were fully melanized. This is the first report of MS formation by T. harzianum or any species of Trichoderma. Furthermore, submerged conidia formation was induced by liquid culture media, but yields, desiccation tolerance, and storage stability varied with C:N ratio and carbon rate. Air-dried MS granules (<4% moisture) retained excellent shelf life under cool and unrefrigerated storage conditions with no loss in conidial production. A low-cost complex nitrogen source based on cottonseed flour effectively supported high MS yields. Amending potting mix with dried MS formulations reduced or eliminated damping-off of melon seedlings caused by Rhizoctonia solani. Together, the results provide insights into the liquid culture production, stabilization process, and bioefficacy of the hitherto unreported MS of T. harzianum as a potential biofungicide for use in integrated management programs against soilborne diseases. Copyright © 2014 The British Mycological Society. All rights reserved.

  11. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds

    PubMed Central

    Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

    2015-01-01

    The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (p < 0.001) negative association was seen between F. hepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables. PMID:26093971

  12. Laser-driven magnetized liner inertial fusion

    DOE PAGES

    Davies, J. R.

    2017-06-05

    A laser-driven, magnetized liner inertial fusion (MagLIF) experiment is designed in this paper for the OMEGA Laser System by scaling down the Z point design to provide the first experimental data on MagLIF scaling. OMEGA delivers roughly 1000× less energy than Z, so target linear dimensions are reduced by factors of ~10. Magneto-inertial fusion electrical discharge system could provide an axial magnetic field of 10 T. Two-dimensional hydrocode modeling indicates that a single OMEGA beam can preheat the fuel to a mean temperature of ~200 eV, limited by mix caused by heat flow into the wall. One-dimensional magnetohydrodynamic (MHD) modelingmore » is used to determine the pulse duration and fuel density that optimize neutron yield at a fuel convergence ratio of roughly 25 or less, matching the Z point design, for a range of shell thicknesses. A relatively thinner shell, giving a higher implosion velocity, is required to give adequate fuel heating on OMEGA compared to Z because of the increase in thermal losses in smaller targets. Two-dimensional MHD modeling of the point design gives roughly a 50% reduction in compressed density, temperature, and magnetic field from 1-D because of end losses. Finally, scaling up the OMEGA point design to the MJ laser energy available on the National Ignition Facility gives a 500-fold increase in neutron yield in 1-D modeling.« less

  13. Laser-driven magnetized liner inertial fusion

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

    Davies, J. R.

    A laser-driven, magnetized liner inertial fusion (MagLIF) experiment is designed in this paper for the OMEGA Laser System by scaling down the Z point design to provide the first experimental data on MagLIF scaling. OMEGA delivers roughly 1000× less energy than Z, so target linear dimensions are reduced by factors of ~10. Magneto-inertial fusion electrical discharge system could provide an axial magnetic field of 10 T. Two-dimensional hydrocode modeling indicates that a single OMEGA beam can preheat the fuel to a mean temperature of ~200 eV, limited by mix caused by heat flow into the wall. One-dimensional magnetohydrodynamic (MHD) modelingmore » is used to determine the pulse duration and fuel density that optimize neutron yield at a fuel convergence ratio of roughly 25 or less, matching the Z point design, for a range of shell thicknesses. A relatively thinner shell, giving a higher implosion velocity, is required to give adequate fuel heating on OMEGA compared to Z because of the increase in thermal losses in smaller targets. Two-dimensional MHD modeling of the point design gives roughly a 50% reduction in compressed density, temperature, and magnetic field from 1-D because of end losses. Finally, scaling up the OMEGA point design to the MJ laser energy available on the National Ignition Facility gives a 500-fold increase in neutron yield in 1-D modeling.« less

  14. Prospecting of popcorn hybrids for resistance to fall armyworm.

    PubMed

    Crubelati-Mulati, N C S; Scapim, C A; Albuquerque, F A; Amaral Junior, A T; Vivas, M; Rodovalho, M A

    2014-08-26

    The fall armyworm, Spodoptera frugiperda, is the pest that causes the greatest economic losses for both common corn and popcorn crops, and the use of resistant plant genotypes is an important tool for integrated pest management. The goal of the present study was to evaluate the damage caused by S. frugiperda on single-cross popcorn hybrids under field conditions with natural infestation as well as to study the effect of 11 popcorn hybrids on the S. frugiperda life cycle under laboratory conditions. A completely randomized block design with 4 replicates was used for the field experiment, and a completely randomized design with 10 replicates was used for the laboratory experiment. In the field experiment, the damage caused by fall armyworm, grain yield, and popping expansion were quantified, and a diallel analysis was performed to select the best hybrids. For the laboratory experiment, caterpillars were obtained from laboratory cultures kept on an artificial diet and were fed with leaves from the 11 hybrids. Hybrids P7.0 x P9.4, P7.1 x P9.6, P7.2.0 x P9.3, P7.4.0 x P9.1 and P7.4.1 x P9.4 exhibited negative specific combining ability for injury by fall armyworm and positive specific combining ability for yield and popping expansion. In the laboratory experiment, the hybrids influenced the mean larval stage duration, mean larval mass, final larval mass, pupal stage duration, mean pupal mass, and adult longevity.

  15. Weather based risks and insurances for agricultural production

    NASA Astrophysics Data System (ADS)

    Gobin, Anne

    2015-04-01

    Extreme weather events such as frost, drought, heat waves and rain storms can have devastating effects on cropping systems. According to both the agriculture and finance sectors, a risk assessment of extreme weather events and their impact on cropping systems is needed. The principle of return periods or frequencies of natural hazards is adopted in many countries as the basis of eligibility for the compensation of associated losses. For adequate risk management and eligibility, hazard maps for events with a 20-year return period are often used. Damages due to extreme events are strongly dependent on crop type, crop stage, soil type and soil conditions. The impact of extreme weather events particularly during the sensitive periods of the farming calendar therefore requires a modelling approach to capture the mixture of non-linear interactions between the crop, its environment and the occurrence of the meteorological event in the farming calendar. Physically based crop models such as REGCROP (Gobin, 2010) assist in understanding the links between different factors causing crop damage. Subsequent examination of the frequency, magnitude and impacts of frost, drought, heat stress and soil moisture stress in relation to the cropping season and crop sensitive stages allows for risk profiles to be confronted with yields, yield losses and insurance claims. The methodology is demonstrated for arable food crops, bio-energy crops and fruit. The perspective of rising risk-exposure is exacerbated further by limited aid received for agricultural damage, an overall reduction of direct income support to farmers and projected intensification of weather extremes with climate change. Though average yields have risen continuously due to technological advances, there is no evidence that relative tolerance to adverse weather events has improved. The research is funded by the Belgian Science Policy Organisation (Belspo) under contract nr SD/RI/03A.

  16. Numerical investigation of plasma edge transport and limiter heat fluxes in Wendelstein 7-X startup plasmas with EMC3-EIRENE

    NASA Astrophysics Data System (ADS)

    Effenberg, F.; Feng, Y.; Schmitz, O.; Frerichs, H.; Bozhenkov, S. A.; Hölbe, H.; König, R.; Krychowiak, M.; Pedersen, T. Sunn; Reiter, D.; Stephey, L.; W7-X Team

    2017-03-01

    The results of a first systematic assessment of plasma edge transport processes for the limiter startup configuration at Wendelstein 7-X are presented. This includes an investigation of transport from intrinsic and externally injected impurities and their impact on the power balance and limiter heat fluxes. The fully 3D coupled plasma fluid and kinetic neutral transport Monte Carlo code EMC3-EIRENE is used. The analysis of the magnetic topology shows that the poloidally and toroidally localized limiters cause a 3D helical scrape-off layer (SOL) consisting of magnetic flux tubes of three different connection lengths L C. The transport in the helical SOL is governed by L C as topological scale length for the parallel plasma loss channel to the limiters. A clear modulation of the plasma pressure with L C is seen. The helical flux tube topology results in counter streaming sonic plasma flows. The heterogeneous SOL plasma structure yields an uneven limiter heat load distribution with localized peaking. Assuming spatially constant anomalous transport coefficients, increasing plasma density yields a reduction of the maximum peak heat loads from 12 MWm-2 to 7.5 MWm-2 and a broadening of the deposited heat fluxes. The impact of impurities on the limiter heat loads is studied by assuming intrinsic carbon impurities eroded from the limiter surfaces with a gross chemical sputtering yield of 2 % . The resulting radiative losses account for less than 10% of the input power in the power balance with marginal impact on the limiter heat loads. It is shown that a significant mitigation of peak heat loads, 40-50%, can be achieved with controlled impurity seeding with nitrogen and neon, which is a method of particular interest for the later island divertor phase.

  17. Emergence of wheat blast in Bangladesh was caused by a South American lineage of Magnaporthe oryzae.

    PubMed

    Islam, M Tofazzal; Croll, Daniel; Gladieux, Pierre; Soanes, Darren M; Persoons, Antoine; Bhattacharjee, Pallab; Hossain, Md Shaid; Gupta, Dipali Rani; Rahman, Md Mahbubur; Mahboob, M Golam; Cook, Nicola; Salam, Moin U; Surovy, Musrat Zahan; Sancho, Vanessa Bueno; Maciel, João Leodato Nunes; NhaniJúnior, Antonio; Castroagudín, Vanina Lilián; Reges, Juliana T de Assis; Ceresini, Paulo Cezar; Ravel, Sebastien; Kellner, Ronny; Fournier, Elisabeth; Tharreau, Didier; Lebrun, Marc-Henri; McDonald, Bruce A; Stitt, Timothy; Swan, Daniel; Talbot, Nicholas J; Saunders, Diane G O; Win, Joe; Kamoun, Sophien

    2016-10-03

    In February 2016, a new fungal disease was spotted in wheat fields across eight districts in Bangladesh. The epidemic spread to an estimated 15,000 hectares, about 16 % of the cultivated wheat area in Bangladesh, with yield losses reaching up to 100 %. Within weeks of the onset of the epidemic, we performed transcriptome sequencing of symptomatic leaf samples collected directly from Bangladeshi fields. Reinoculation of seedlings with strains isolated from infected wheat grains showed wheat blast symptoms on leaves of wheat but not rice. Our phylogenomic and population genomic analyses revealed that the wheat blast outbreak in Bangladesh was most likely caused by a wheat-infecting South American lineage of the blast fungus Magnaporthe oryzae. Our findings suggest that genomic surveillance can be rapidly applied to monitor plant disease outbreaks and provide valuable information regarding the identity and origin of the infectious agent.

  18. Pyramiding transgenes for multiple resistance in rice against bacterial blight, yellow stem borer and sheath blight.

    PubMed

    Datta, K; Baisakh, N; Thet, K Maung; Tu, J; Datta, S K

    2002-12-01

    Here we describe the development of transgene-pyramided stable elite rice lines resistant to disease and insect pests by conventional crossing of two transgenic parental lines transformed independently with different genes. The Xa21 gene (resistance to bacterial blight), the Bt fusion gene (for insect resistance) and the chitinase gene (for tolerance of sheath blight) were combined in a single rice line by reciprocal crossing of two transgenic homozygous IR72 lines. F4 plant lines carrying all the genes of interest stably were identified using molecular methods. The identified lines, when exposed to infection caused by Xanthomonas oryzae pv oryzae, showed resistance to bacterial blight. Neonate larval mortality rates of yellow stem borer ( Scirpophaga incertulas) in an insect bioassay of the same identified lines were 100%. The identified line pyramided with different genes to protect against yield loss showed high tolerance of sheath blight disease caused by Rhizoctonia solani.

  19. Insights into Bacteriophage Application in Controlling Vibrio Species

    PubMed Central

    Letchumanan, Vengadesh; Chan, Kok-Gan; Pusparajah, Priyia; Saokaew, Surasak; Duangjai, Acharaporn; Goh, Bey-Hing; Ab Mutalib, Nurul-Syakima; Lee, Learn-Han

    2016-01-01

    Bacterial infections from various organisms including Vibrio sp. pose a serious hazard to humans in many forms from clinical infection to affecting the yield of agriculture and aquaculture via infection of livestock. Vibrio sp. is one of the main foodborne pathogens causing human infection and is also a common cause of losses in the aquaculture industry. Prophylactic and therapeutic usage of antibiotics has become the mainstay of managing this problem, however, this in turn led to the emergence of multidrug resistant strains of bacteria in the environment; which has raised awareness of the critical need for alternative non-antibiotic based methods of preventing and treating bacterial infections. Bacteriophages – viruses that infect and result in the death of bacteria – are currently of great interest as a highly viable alternative to antibiotics. This article provides an insight into bacteriophage application in controlling Vibrio species as well underlining the advantages and drawbacks of phage therapy. PMID:27486446

  20. Cardiovascular Assessment of Falls in Older People

    PubMed Central

    Tan, Maw Pin; Kenny, Rose Anne

    2006-01-01

    Falls in older people can be caused by underlying cardiovascular disorders, either because of balance instability in persons with background gait and balance disorders, or because of amnesia for loss of consciousness during unwitnessed syncope. Pertinent investigations include a detailed history, 12-lead electrocardiography, lying and standing blood pressure, carotid sinus massage (CSM), head-up tilt, cardiac electrophysiological tests, and ambulatory blood pressure and heart rate monitoring, which includes external and internal cardiac monitoring. The presence of structural heart disease predicts an underlying cardiac cause. Conversely, the absence of either indicates that neurally mediated etiology is likely. CSM and tilt-table testing should be considered in patients with unexplained and recurrent falls. Holter monitoring over 24 hours has a low diagnostic yield. Early use of an implantable loop recorder may be more cost-effective. A dedicated investigation unit increases the likelihood of achieving positive diagnoses and significantly reduces hospital stay and health expenditure. PMID:18047258

  1. Trichothecene resistance in wheat: Development of molecular markers for PDR-type ABC transporter genes.

    PubMed

    Mitterbauer, R; Heinrich, M; Rauscher, R; Lemmens, M; Bürstmayr, H; Adam, G

    2003-03-01

    Infection withFusarium graminearum andF. culmorum not only causes severe yield and quality losses, the most relevant concern is the contamination of cereal foods and feeds with trichothecenes (e.g. deoxynivalenol, DON). The ability to synthesize trichothecenes has been shown to be a virulence factor ofF. graminearum on wheat and, on the other hand, toxin resistance is most likely an important component of field resistance. Our hypothesis is that pleiotropic drug resistance mediated by PDR-type ABC transporter proteins (acting as membrane located drug efflux pumps) is a relevant mechanism of DON resistance not only in yeast but also in wheat. Goal of this project is the development of molecular markers for this gene family for use in marker-assisted plant breeding programs. The technical difficulties caused by the large size of the PDR-family are discussed.

  2. Comprehensive nitrogen budgets for controlled tile drainage fields in eastern ontario, Canada.

    PubMed

    Sunohara, M D; Craiovan, E; Topp, E; Gottschall, N; Drury, C F; Lapen, D R

    2014-03-01

    Excessive N loading from subsurface tile drainage has been linked to water quality degradation. Controlled tile drainage (CTD) has the potential to reduce N losses via tile drainage and boost crop yields. While CTD can reduce N loss from tile drainage, it may increase losses through other pathways. A multiple-year field-scale accounting of major N inputs and outputs during the cropping season was conducted on freely drained and controlled tile drained agricultural fields under corn ( L.)-soybean [ (L.) Merr.] production systems in eastern Ontario, Canada. Greater predicted gaseous N emissions for corn and soybean and greater observed lateral seepage N losses were observed for corn and soybean fields under CTD relative to free-draining fields. However, observed N losses from tile were significantly lower for CTD fields, in relation to freely drained fields. Changes in residual soil N were essentially equivalent between drainage treatments, while mass balance residual terms were systematically negative (slightly more so for CTD). Increases in plant N uptake associated with CTD were observed, probably resulting in higher grain yields for corn and soybean. This study illustrates the benefits of CTD in decreasing subsurface tile drainage N losses and boosting crop yields, while demonstrating the potential for CTD to increase N losses via other pathways related to gaseous emissions and groundwater seepage. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. In vitro propagation of peanut (Arachis hypogaea L.) by shoot tip culture.

    PubMed

    Ozudogru, Elif Aylin; Kaya, Ergun; Lambardi, Maurizio

    2013-01-01

    Peanut (Arachis hypogaea L.), also known as groundnut, is the most important species of Arachis genus, originating from Brazil and Peru. Peanut seeds contain high seed oil, proteins, amino acids, and vitamin E, and are consumed worldwide as edible nut, peanut butter, or candy, and peanut oil extracted from the seeds. The meal remaining after oil extraction is also used for animal feed. However, its narrow germplasm base, together with susceptibility to diseases, pathogens, and weeds, decreases yield and seed quality and causes great economic losses annually. Hence, the optimization of efficient in vitro propagation procedures would be highly effective for peanut propagation, as it would raise yield and improve seed quality and flavor. Earlier reports on traditional micropropagation methods, based on axillary bud proliferation which guarantees the multiplication of true-to-type plants, are still limited. This chapter describes a micropropagation protocol to improve multiple shoot formation from shoot-tip explants by using AgNO(3) in combination with plant growth regulators.

  4. Recombinant protein expression for structural biology in HEK 293F suspension cells: a novel and accessible approach.

    PubMed

    Portolano, Nicola; Watson, Peter J; Fairall, Louise; Millard, Christopher J; Milano, Charles P; Song, Yun; Cowley, Shaun M; Schwabe, John W R

    2014-10-16

    The expression and purification of large amounts of recombinant protein complexes is an essential requirement for structural biology studies. For over two decades, prokaryotic expression systems such as E. coli have dominated the scientific literature over costly and less efficient eukaryotic cell lines. Despite the clear advantage in terms of yields and costs of expressing recombinant proteins in bacteria, the absence of specific co-factors, chaperones and post-translational modifications may cause loss of function, mis-folding and can disrupt protein-protein interactions of certain eukaryotic multi-subunit complexes, surface receptors and secreted proteins. The use of mammalian cell expression systems can address these drawbacks since they provide a eukaryotic expression environment. However, low protein yields and high costs of such methods have until recently limited their use for structural biology. Here we describe a simple and accessible method for expressing and purifying milligram quantities of protein by performing transient transfections of suspension grown HEK (Human Embryonic Kidney) 293 F cells.

  5. The thioredoxin TRX-1 regulates adult lifespan extension induced by dietary restriction in Caenorhabditis elegans

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

    Fierro-Gonzalez, Juan Carlos; Gonzalez-Barrios, Maria; Miranda-Vizuete, Antonio, E-mail: amirviz@upo.es

    Highlights: {yields} First in vivo data for thioredoxin in dietary-restriction-(DR)-induced longevity. {yields} Thioredoxin (trx-1) loss suppresses longevity of eat-2 mutant, a genetic DR model. {yields} trx-1 overexpression extends wild-type longevity, but not that of eat-2 mutant. {yields} Longevity by dietary deprivation (DD), a non-genetic DR model, requires trx-1. {yields} trx-1 expression in ASJ neurons of aging adults is increased in response to DD. -- Abstract: Dietary restriction (DR) is the only environmental intervention known to extend adult lifespan in a wide variety of animal models. However, the genetic and cellular events that mediate the anti-aging programs induced by DR remainmore » elusive. Here, we used the nematode Caenorhabditis elegans to provide the first in vivo evidence that a thioredoxin (TRX-1) regulates adult lifespan extension induced by DR. We found that deletion of the gene trx-1 completely suppressed the lifespan extension caused by mutation of eat-2, a genetic surrogate of DR in the worm. However, trx-1 deletion only partially suppressed the long lifespan caused by mutation of the insulin-like receptor gene daf-2 or by mutation of the sensory cilia gene osm-5. A trx-1::GFP translational fusion expressed from its own promoter in ASJ neurons (Ptrx-1::trx-1::GFP) rescued the trx-1 deletion-mediated suppression of the lifespan extension caused by mutation of eat-2. This rescue was not observed when trx-1::GFP was expressed from the ges-1 promoter in the intestine. In addition, overexpression of Ptrx-1::trx-1::GFP extended lifespan in wild type, but not in eat-2 mutants. trx-1 deletion almost completely suppressed the lifespan extension induced by dietary deprivation (DD), a non-genetic, nutrient-based model of DR in the worm. Moreover, DD upregulated the expression of a trx-1 promoter-driven GFP reporter gene (Ptrx-1::GFP) in ASJ neurons of aging adults, but not that of control Pgpa-9::GFP (which is also expressed in ASJ neurons). We propose that DR activates TRX-1 in ASJ neurons during aging, which in turn triggers TRX-1-dependent mechanisms to extend adult lifespan in the worm.« less

  6. [Comparison of potential yield and resource utilization efficiency of main food crops in three provinces of Northeast China under climate change].

    PubMed

    Wang, Xiao-yu; Yang, Xiao-guang; Sun, Shuang; Xie, Wen-juan

    2015-10-01

    Based on the daily data of 65 meteorological stations from 1961 to 2010 and the crop phenology data in the potential cultivation zones of thermophilic and chimonophilous crops in Northeast China, the crop potential yields were calculated through step-by-step correction method. The spatio-temporal distribution of the crop potential yields at different levels was analyzed. And then we quantified the limitations of temperature and precipitation on the crop potential yields and compared the differences in the climatic resource utilization efficiency. The results showed that the thermal potential yields of six crops (including maize, rice, spring wheat, sorghum, millet and soybean) during the period 1961-2010 deceased from west to east. The climatic potential yields of the five crops (spring wheat not included) were higher in the south than in the north. The potential yield loss rate due to temperature limitations of the six crops presented a spatial distribution pattern and was higher in the east than in the west. Among the six main crops, the yield potential loss rate due to temperature limitation of the soybean was the highest (51%), and those of the other crops fluctuated within the range of 33%-41%. The potential yield loss rate due to water limitation had an obvious regional difference, and was high in Songnen Plain and Changbai Mountains. The potential yield loss rate of spring wheat was the highest (50%), and those of the other four rainfed crops fluctuated within the range of 8%-10%. The solar energy utilization efficiency of the six main crops ranged from 0.9% to 2.7%, in the order of maize> sorghum>rice>millet>spring wheat>soybean. The precipitation utilization efficiency of the maize, sorghum, spring wheat, millet and soybean under rainfed conditions ranged from 8 to 35 kg . hm-2 . mm-1, in the order of maize>sorghum>spring wheat>millet>soybean. In those areas with lower efficiency of solar energy utilization and precipitation utilization, such as Changbai Mountains and the south of Lesser Khingan Mountains, measures could be taken to increase the efficiency of resource utilization such as rational close-planting, selection of droughtresistant varieties, proper and timely fertilization, farming for soil water storage, optimization of crop layout and so on.

  7. Runoff, nitrogen (N) and phosphorus (P) losses from purple slope cropland soil under rating fertilization in Three Gorges Region.

    PubMed

    Bouraima, Abdel-Kabirou; He, Binghui; Tian, Taiqiang

    2016-03-01

    Soil erosion along with soil particles and nutrients losses is detrimental to crop production. We carried out a 5-year (2010 to 2014) study to characterize the soil erosion and nitrogen and phosphorus losses caused by rainfall under different fertilizer application levels in order to provide a theoretical evidence for the agricultural production and coordinate land management to improve ecological environment. The experiment took place under rotation cropping, winter wheat-summer maize, on a 15° slope purple soil in Chongqing (China) within the Three Gorges Region (TGR). Four treatments, control (CK) without fertilizer, combined manure with chemical fertilizer (T1), chemical fertilization (T2), and chemical fertilizer with increasing fertilization (T3), were designed on experimental runoff plots for a long-term observation aiming to study their effects on soil erosion and nutrients losses. The results showed that fertilization reduced surface runoff and nutrient losses as compared to CK. T1, T2, and T3, compared to CK, reduced runoff volume by 35.7, 29.6, and 16.8 %, respectively and sediment yield by 40.5, 20.9, and 49.6 %, respectively. Regression analysis results indicated that there were significant relationships between soil loss and runoff volume in all treatments. The combined manure with chemical fertilizer (T1) treatment highly reduced total nitrogen and total phosphorus losses by 41.2 and 33.33 %, respectively as compared with CK. Through this 5-year experiment, we can conclude that, on the sloping purple soil, the combined application of manure with fertilizer is beneficial for controlling runoff sediments losses and preventing soil erosion.

  8. Will weight loss cause significant dosimetric changes of target volumes and organs at risk in nasopharyngeal carcinoma treated with intensity-modulated radiation therapy?

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

    Chen, Chuanben; Fei, Zhaodong; Chen, Lisha

    This study aimed to quantify dosimetric effects of weight loss for nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). Overall, 25 patients with NPC treated with IMRT were enrolled. We simulated weight loss during IMRT on the computer. Weight loss model was based on the planning computed tomography (CT) images. The original external contour of head and neck was labeled plan 0, and its volume was regarded as pretreatment normal weight. We shrank the external contour with different margins (2, 3, and 5 mm) and generated new external contours of head and neck. The volumes of reconstructed external contoursmore » were regarded as weight during radiotherapy. After recontouring outlines, the initial treatment plan was mapped to the redefined CT scans with the same beam configurations, yielding new plans. The computer model represented a theoretical proportional weight loss of 3.4% to 13.7% during the course of IMRT. The dose delivered to the planning target volume (PTV) of primary gross tumor volume and clinical target volume significantly increased by 1.9% to 2.9% and 1.8% to 2.9% because of weight loss, respectively. The dose to the PTV of gross tumor volume of lymph nodes fluctuated from −2.0% to 1.0%. The dose to the brain stem and the spinal cord was increased (p < 0.001), whereas the dose to the parotid gland was decreased (p < 0.001). Weight loss may lead to significant dosimetric change during IMRT. Repeated scanning and replanning for patients with NPC with an obvious weight loss may be necessary.« less

  9. Control of the external photoluminescent quantum yield of emitters coupled to nanoantenna phased arrays

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

    Guo, Ke; Verschuuren, Marc A.; Lozano, Gabriel

    2015-08-21

    Optical losses in metals represent the largest limitation to the external quantum yield of emitters coupled to plasmonic antennas. These losses can be at the emission wavelength, but they can be more important at shorter wavelengths, i.e., at the excitation wavelength of the emitters, where the conductivity of metals is usually lower. We present accurate measurements of the absolute external photoluminescent quantum yield of a thin layer of emitting material deposited over a periodic nanoantenna phased array. Emission and absorptance measurements of the sample are performed using a custom-made setup including an integrating sphere and variable angle excitation. The measurementsmore » reveal a strong dependence of the external quantum yield on the angle at which the optical field excites the sample. Such behavior is attributed to the coupling between far-field illumination and near-field excitation mediated by the collective resonances supported by the array. Numerical simulations confirm that the inherent losses associated with the metal can be greatly reduced by selecting an optimum angle of illumination, which boosts the light conversion efficiency in the emitting layer. This combined experimental and numerical characterization of the emission from plasmonic arrays reveals the need to carefully design the illumination to achieve the maximum external quantum yield.« less

  10. Mitochondrial remodeling following fission inhibition by 15d-PGJ2 involves molecular changes in mitochondrial fusion protein OPA1

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

    Kar, Rekha; Department of Biochemistry, UT Health Science Center at San Antonio, San Antonio, TX 78229; Mishra, Nandita

    2010-09-03

    Research highlights: {yields} Chemical inhibition of fission protein Drp1 leads to mitochondrial fusion. {yields} Increased fusion stimulates molecular changes in mitochondrial fusion protein OPA1. {yields} Proteolysis of larger isoforms, new synthesis and ubiquitination of OPA1 occur. {yields} Loss of mitochondrial tubular rigidity and disorganization of cristae. {yields} Generation of large swollen dysfunctional mitochondria. -- Abstract: We showed earlier that 15 deoxy {Delta}{sup 12,14} prostaglandin J2 (15d-PGJ2) inactivates Drp1 and induces mitochondrial fusion . However, prolonged incubation of cells with 15d-PGJ2 resulted in remodeling of fused mitochondria into large swollen mitochondria with irregular cristae structure. While initial fusion of mitochondria bymore » 15d-PGJ2 required the presence of both outer (Mfn1 and Mfn2) and inner (OPA1) mitochondrial membrane fusion proteins, later mitochondrial changes involved increased degradation of the fusion protein OPA1 and ubiquitination of newly synthesized OPA1 along with decreased expression of Mfn1 and Mfn2, which likely contributed to the loss of tubular rigidity, disorganization of cristae, and formation of large swollen degenerated dysfunctional mitochondria. Similar to inhibition of Drp1 by 15d-PGJ2, decreased expression of fission protein Drp1 by siRNA also resulted in the loss of fusion proteins. Prevention of 15d-PGJ2 induced mitochondrial elongation by thiol antioxidants prevented not only loss of OPA1 isoforms but also its ubiquitination. These findings provide novel insights into unforeseen complexity of molecular events that modulate mitochondrial plasticity.« less

  11. Post-flowering night respiration and altered sink activity account for high night temperature-induced grain yield and quality loss in rice (Oryza sativa L.).

    PubMed

    Bahuguna, Rajeev N; Solis, Celymar A; Shi, Wanju; Jagadish, Krishna S V

    2017-01-01

    High night temperature (HNT) is a major constraint to sustaining global rice production under future climate. Physiological and biochemical mechanisms were elucidated for HNT-induced grain yield and quality loss in rice. Contrasting rice cultivars (N22, tolerant; Gharib, susceptible; IR64, high yielding with superior grain quality) were tested under control (23°C) and HNT (29°C) using unique field-based tents from panicle initiation till physiological maturity. HNT affected 1000 grain weight, grain yield, grain chalk and amylose content in Gharib and IR64. HNT increased night respiration (Rn) accounted for higher carbon losses during post-flowering phase. Gharib and IR64 recorded 16 and 9% yield reduction with a 63 and 35% increase in average post-flowering Rn under HNT, respectively. HNT altered sugar accumulation in the rachis and spikelets across the cultivars with Gharib and IR64 recording higher sugar accumulation in the rachis. HNT reduced panicle starch content in Gharib (22%) and IR64 (11%) at physiological maturity, but not in the tolerant N22. At the enzymatic level, HNT reduced sink strength with lower cell wall invertase and sucrose synthase activity in Gharib and IR64, which affected starch accumulation in the developing grain, thereby reducing grain weight and quality. Interestingly, N22 recorded lower Rn-mediated carbon losses and minimum impact on sink strength under HNT. Mechanistic responses identified will facilitate crop models to precisely estimate HNT-induced damage under future warming scenarios. © 2016 Scandinavian Plant Physiology Society.

  12. Diagnostic Yield of Computed Tomography Scan for Pediatric Hearing Loss: A Systematic Review

    PubMed Central

    Chen, Jenny X.; Kachniarz, Bart; Shin, Jennifer J.

    2015-01-01

    Background Computed tomography (CT) has been used in the assessment of pediatric hearing loss, but concern regarding radiation risk and increased utilization of magnetic resonance imaging (MRI) have prompted us toward a more quantitative and sophisticated understanding of CT’s potential diagnostic yield. Objective To perform a systematic review to analyze the diagnostic yield of CT for pediatric hearing loss, including subgroup evaluation according to impairment severity and laterality, as well as the specific findings of enlarged vestibular aqueduct and narrow cochlear nerve canal. Data Sources PubMed, EMBASE, and the Cochrane Library were assessed from the date of their inception to December 2013. In addition, manual searches of bibliographies were performed and topic experts were contacted. Review Methods Data from studies describing the use of CT in the diagnostic evaluation of pediatric patients with hearing loss of unknown etiology were evaluated, according to a priori inclusion/exclusion criteria. Two independent evaluators corroborated the extracted data. Heterogeneity was evaluated according to the I2 statistic. Results In 50 criteria-meeting studies, the overall diagnostic yield of CT ranged from 7% to 74%, with the strongest and aggregate data demonstrating a point estimate of 30%. This estimate corresponded to a number needed to image of 4 (range, 2–15). The most commonly identified findings were enlarged vestibular aqueduct and cochlear anomalies. The largest studies showed a 4% to 7% yield for narrow cochlear nerve canal. Conclusion These data, along with similar analyses of radiation risk and risks/benefits of sedated MRI, may be used to help guide the choice of diagnostic imaging. PMID:25186339

  13. 7 CFR 1437.105 - Determining payments for low yield.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Determining payments for low yield. 1437.105 Section 1437.105 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT... for low yield. (a) Except to the extent that the loss calculation provisions of other subparts apply...

  14. Impacts of 1.5 versus 2.0 °C on cereal yields in the West African Sudan Savanna

    NASA Astrophysics Data System (ADS)

    Faye, Babacar; Webber, Heidi; Naab, Jesse B.; MacCarthy, Dilys S.; Adam, Myriam; Ewert, Frank; Lamers, John P. A.; Schleussner, Carl-Friedrich; Ruane, Alex; Gessner, Ursula; Hoogenboom, Gerrit; Boote, Ken; Shelia, Vakhtang; Saeed, Fahad; Wisser, Dominik; Hadir, Sofia; Laux, Patrick; Gaiser, Thomas

    2018-03-01

    To reduce the risks of climate change, governments agreed in the Paris Agreement to limit global temperature rise to less than 2.0 °C above pre-industrial levels, with the ambition to keep warming to 1.5 °C. Charting appropriate mitigation responses requires information on the costs of mitigating versus associated damages for the two levels of warming. In this assessment, a critical consideration is the impact on crop yields and yield variability in regions currently challenged by food insecurity. The current study assessed impacts of 1.5 °C versus 2.0 °C on yields of maize, pearl millet and sorghum in the West African Sudan Savanna using two crop models that were calibrated with common varieties from experiments in the region with management reflecting a range of typical sowing windows. As sustainable intensification is promoted in the region for improving food security, simulations were conducted for both current fertilizer use and for an intensification case (fertility not limiting). With current fertilizer use, results indicated 2% units higher losses for maize and sorghum with 2.0 °C compared to 1.5 °C warming, with no change in millet yields for either scenario. In the intensification case, yield losses due to climate change were larger than with current fertilizer levels. However, despite the larger losses, yields were always two to three times higher with intensification, irrespective of the warming scenario. Though yield variability increased with intensification, there was no interaction with warming scenario. Risk and market analysis are needed to extend these results to understand implications for food security.

  15. Mechanisms and causes of wear in tooth enamel: implications for hominin diets

    PubMed Central

    Lucas, Peter W.; Omar, Ridwaan; Al-Fadhalah, Khaled; Almusallam, Abdulwahab S.; Henry, Amanda G.; Michael, Shaji; Thai, Lidia Arockia; Watzke, Jörg; Strait, David S.; Atkins, Anthony G.

    2013-01-01

    The wear of teeth is a major factor limiting mammalian lifespans in the wild. One method of describing worn surfaces, dental microwear texture analysis, has proved powerful for reconstructing the diets of extinct vertebrates, but has yielded unexpected results in early hominins. In particular, although australopiths exhibit derived craniodental features interpreted as adaptations for eating hard foods, most do not exhibit microwear signals indicative of this diet. However, no experiments have yet demonstrated the fundamental mechanisms and causes of this wear. Here, we report nanowear experiments where individual dust particles, phytoliths and enamel chips were slid across a flat enamel surface. Microwear features produced were influenced strongly by interacting mechanical properties and particle geometry. Quartz dust was a rigid abrasive, capable of fracturing and removing enamel pieces. By contrast, phytoliths and enamel chips deformed during sliding, forming U-shaped grooves or flat troughs in enamel, without tissue loss. Other plant tissues seem too soft to mark enamel, acting as particle transporters. We conclude that dust has overwhelming importance as a wear agent and that dietary signals preserved in dental microwear are indirect. Nanowear studies should resolve controversies over adaptive trends in mammals like enamel thickening or hypsodonty that delay functional dental loss. PMID:23303220

  16. Estimation of genetic parameters for heat stress, including dominance gene effects, on milk yield in Thai Holstein dairy cattle.

    PubMed

    Boonkum, Wuttigrai; Duangjinda, Monchai

    2015-03-01

    Heat stress in tropical regions is a major cause that strongly negatively affects to milk production in dairy cattle. Genetic selection for dairy heat tolerance is powerful technique to improve genetic performance. Therefore, the current study aimed to estimate genetic parameters and investigate the threshold point of heat stress for milk yield. Data included 52 701 test-day milk yield records for the first parity from 6247 Thai Holstein dairy cattle, covering the period 1990 to 2007. The random regression test day model with EM-REML was used to estimate variance components, genetic parameters and milk production loss. A decline in milk production was found when temperature and humidity index (THI) exceeded a threshold of 74, also it was associated with the high percentage of Holstein genetics. All variance component estimates increased with THI. The estimate of heritability of test-day milk yield was 0.231. Dominance variance as a proportion to additive variance (0.035) indicated that non-additive effects might not be of concern for milk genetics studies in Thai Holstein cattle. Correlations between genetic and permanent environmental effects, for regular conditions and due to heat stress, were - 0.223 and - 0.521, respectively. The heritability and genetic correlations from this study show that simultaneous selection for milk production and heat tolerance is possible. © 2014 Japanese Society of Animal Science.

  17. Bilateral sudden sensorineural hearing loss as a first symptom of infective endocarditis: two case reports.

    PubMed

    Chroni, M; Prappa, E; Kokkevi, I

    2018-04-01

    Septic emboli are an unusual cause of sudden sensorineural hearing loss, for which few reports exist in the literature. This paper presents two cases of sudden sensorineural hearing loss, initially considered as idiopathic, but which were caused by septic emboli. Hearing loss in these cases was bilateral, sequential and total. The first patient had mild fever one week prior to their presentation with sudden sensorineural hearing loss; the other patient had no additional symptoms at presentation. These patients were later diagnosed with infective endocarditis, at two and seven months following the sudden sensorineural hearing loss respectively, showing that septic emboli had been the cause of sudden sensorineural hearing loss. Septic emboli should be considered as a possible cause of sudden sensorineural hearing loss in cases of total hearing loss. This form of hearing loss should prompt the otolaryngologist to further investigate for infective endocarditis.

  18. Reassessment of the potential economic impact of cattle parasites in Brazil.

    PubMed

    Grisi, Laerte; Leite, Romário Cerqueira; Martins, João Ricardo de Souza; Barros, Antonio Thadeu Medeiros de; Andreotti, Renato; Cançado, Paulo Henrique Duarte; León, Adalberto Angel Pérez de; Pereira, Jairo Barros; Villela, Humberto Silva

    2014-01-01

    The profitability of livestock activities can be diminished significantly by the effects of parasites. Economic losses caused by cattle parasites in Brazil were estimated on an annual basis, considering the total number of animals at risk and the potential detrimental effects of parasitism on cattle productivity. Estimates in U.S. dollars (USD) were based on reported yield losses among untreated animals and reflected some of the effects of parasitic diseases. Relevant parasites that affect cattle productivity in Brazil, and their economic impact in USD billions include: gastrointestinal nematodes - $7.11; cattle tick (Rhipicephalus (Boophilus) microplus) - $3.24; horn fly (Haematobia irritans) - $2.56; cattle grub (Dermatobia hominis) - $0.38; New World screwworm fly (Cochliomyia hominivorax) - $0.34; and stable fly (Stomoxys calcitrans) - $0.34. The combined annual economic loss due to internal and external parasites of cattle in Brazil considered here was estimated to be at least USD 13.96 billion. These findings are discussed in the context of methodologies and research that are required in order to improve the accuracy of these economic impact assessments. This information needs to be taken into consideration when developing sustainable policies for mitigating the impact of parasitism on the profitability of Brazilian cattle producers.

  19. Maize Lethal Necrosis (MLN), an Emerging Threat to Maize-Based Food Security in Sub-Saharan Africa.

    PubMed

    Mahuku, George; Lockhart, Benham E; Wanjala, Bramwel; Jones, Mark W; Kimunye, Janet Njeri; Stewart, Lucy R; Cassone, Bryan J; Sevgan, Subramanian; Nyasani, Johnson O; Kusia, Elizabeth; Kumar, P Lava; Niblett, C L; Kiggundu, Andrew; Asea, Godfrey; Pappu, Hanu R; Wangai, Anne; Prasanna, Boddupalli M; Redinbaugh, Margaret G

    2015-07-01

    In sub-Saharan Africa, maize is a staple food and key determinant of food security for smallholder farming communities. Pest and disease outbreaks are key constraints to maize productivity. In September 2011, a serious disease outbreak, later diagnosed as maize lethal necrosis (MLN), was reported on maize in Kenya. The disease has since been confirmed in Rwanda and the Democratic Republic of Congo, and similar symptoms have been reported in Tanzania, Uganda, South Sudan, and Ethiopia. In 2012, yield losses of up to 90% resulted in an estimated grain loss of 126,000 metric tons valued at $52 million in Kenya alone. In eastern Africa, MLN was found to result from coinfection of maize with Maize chlorotic mottle virus (MCMV) and Sugarcane mosaic virus (SCMV), although MCMV alone appears to cause significant crop losses. We summarize here the results of collaborative research undertaken to understand the biology and epidemiology of MLN in East Africa and to develop disease management strategies, including identification of MLN-tolerant maize germplasm. We discuss recent progress, identify major issues requiring further research, and discuss the possible next steps for effective management of MLN.

  20. A new urease-inhibiting formulation decreases ammonia volatilization and improves maize nitrogen utilization in North China Plain

    PubMed Central

    Li, Qianqian; Cui, Xiaoqing; Liu, Xuejun; Roelcke, Marco; Pasda, Gregor; Zerulla, Wolfram; Wissemeier, Alexander H.; Chen, Xinping; Goulding, Keith; Zhang, Fusuo

    2017-01-01

    Overuse of urea, low nitrogen (N) utilization, and large N losses are common in maize production in North China Plain (NCP). To solve these problems, we conducted two field experiments at Shangzhuang and Quzhou in NCP to test the ability of a newly developed urease inhibitor product Limus® to decrease NH3 volatilization from urea applied to maize. Grain yield, apparent N recovery efficiency (REN) and N balance when using urea applied with or without Limus were also measured over two maize growing seasons. Cumulative NH3 loss in the two weeks following urea application without Limus ranged from 9–108 kg N ha−1, while Limus addition significantly decreased NH3 loss by a mean of 84%. Urea with Limus did not significantly increase maize yields (P < 0.05) compared with urea alone. However, a significant 11–17% improvement in REN with Limus was observed at QZ. The use of urea-N plus Limus would permit a reduction in N applications of 55–60% compared to farmers’ practice and/or further 20% N saving compared with optimized urea-N rate (150 kg N ha−1, based on N requirement by target yield of 7.5 t ha−1), and would achieve the same maize yields but with significantly decreased NH3 loss and increased N utilization. PMID:28272451

  1. A new urease-inhibiting formulation decreases ammonia volatilization and improves maize nitrogen utilization in North China Plain

    NASA Astrophysics Data System (ADS)

    Li, Qianqian; Cui, Xiaoqing; Liu, Xuejun; Roelcke, Marco; Pasda, Gregor; Zerulla, Wolfram; Wissemeier, Alexander H.; Chen, Xinping; Goulding, Keith; Zhang, Fusuo

    2017-03-01

    Overuse of urea, low nitrogen (N) utilization, and large N losses are common in maize production in North China Plain (NCP). To solve these problems, we conducted two field experiments at Shangzhuang and Quzhou in NCP to test the ability of a newly developed urease inhibitor product Limus® to decrease NH3 volatilization from urea applied to maize. Grain yield, apparent N recovery efficiency (REN) and N balance when using urea applied with or without Limus were also measured over two maize growing seasons. Cumulative NH3 loss in the two weeks following urea application without Limus ranged from 9-108 kg N ha-1, while Limus addition significantly decreased NH3 loss by a mean of 84%. Urea with Limus did not significantly increase maize yields (P < 0.05) compared with urea alone. However, a significant 11-17% improvement in REN with Limus was observed at QZ. The use of urea-N plus Limus would permit a reduction in N applications of 55-60% compared to farmers’ practice and/or further 20% N saving compared with optimized urea-N rate (150 kg N ha-1, based on N requirement by target yield of 7.5 t ha-1), and would achieve the same maize yields but with significantly decreased NH3 loss and increased N utilization.

  2. Barley yellow dwarf virus Infection Leads to Higher Chemical Defense Signals and Lower Electrophysiological Reactions in Susceptible Compared to Tolerant Barley Genotypes.

    PubMed

    Paulmann, Maria K; Kunert, Grit; Zimmermann, Matthias R; Theis, Nina; Ludwig, Anatoli; Meichsner, Doreen; Oelmüller, Ralf; Gershenzon, Jonathan; Habekuss, Antje; Ordon, Frank; Furch, Alexandra C U; Will, Torsten

    2018-01-01

    Barley yellow dwarf virus (BYDV) is a phloem limited virus that is persistently transmitted by aphids. Due to huge yield losses in agriculture, the virus is of high economic relevance. Since the control of the virus itself is not possible, tolerant barley genotypes are considered as the most effective approach to avoid yield losses. Although several genes and quantitative trait loci are known and used in barley breeding for virus tolerance, little is known about molecular and physiological backgrounds of this trait. Therefore, we compared the anatomy and early defense responses of a virus susceptible to those of a virus-tolerant cultivar. One of the very early defense responses is the transmission of electrophysiological reactions. Electrophysiological reactions to BYDV infection might differ between susceptible and tolerant cultivars, since BYDV causes disintegration of sieve elements in susceptible cultivars. The structure of vascular bundles, xylem vessels and sieve elements was examined using microscopy. All three were significantly decreased in size in infected susceptible plants where the virus causes disintegration of sieve elements. This could be associated with an uncontrolled ion exchange between the sieve-element lumen and apoplast. Further, a reduced electrophysiological isolation would negatively affect the propagation of electrophysiological reactions. To test the influence of BYDV infection on electrophysiological reactions, electropotential waves (EPWs) induced by leaf-tip burning were recorded using aphids as bioelectrodes. EPWs in infected susceptible plants disappeared already after 10 cm in contrast to those in healthy susceptible or infected tolerant or healthy tolerant plants. Another early plant defense reaction is an increase in reactive oxygen species (ROS). Using a fluorescent dye, we found a significant increase in ROS content in infected susceptible plants but not in infected tolerant plants. Similar results were found for the phytohormones abscisic acid and three jasmonates. Salicylic acid levels were generally higher after BYDV infection compared to uninfected plants. Heat stimulation caused an increase in jasmonates. By shedding light on the plant defense mechanisms against BYDV, this study, provides further knowledge for breeding virus tolerant plants.

  3. Barley yellow dwarf virus Infection Leads to Higher Chemical Defense Signals and Lower Electrophysiological Reactions in Susceptible Compared to Tolerant Barley Genotypes

    PubMed Central

    Paulmann, Maria K.; Kunert, Grit; Zimmermann, Matthias R.; Theis, Nina; Ludwig, Anatoli; Meichsner, Doreen; Oelmüller, Ralf; Gershenzon, Jonathan; Habekuss, Antje; Ordon, Frank; Furch, Alexandra C. U.; Will, Torsten

    2018-01-01

    Barley yellow dwarf virus (BYDV) is a phloem limited virus that is persistently transmitted by aphids. Due to huge yield losses in agriculture, the virus is of high economic relevance. Since the control of the virus itself is not possible, tolerant barley genotypes are considered as the most effective approach to avoid yield losses. Although several genes and quantitative trait loci are known and used in barley breeding for virus tolerance, little is known about molecular and physiological backgrounds of this trait. Therefore, we compared the anatomy and early defense responses of a virus susceptible to those of a virus-tolerant cultivar. One of the very early defense responses is the transmission of electrophysiological reactions. Electrophysiological reactions to BYDV infection might differ between susceptible and tolerant cultivars, since BYDV causes disintegration of sieve elements in susceptible cultivars. The structure of vascular bundles, xylem vessels and sieve elements was examined using microscopy. All three were significantly decreased in size in infected susceptible plants where the virus causes disintegration of sieve elements. This could be associated with an uncontrolled ion exchange between the sieve-element lumen and apoplast. Further, a reduced electrophysiological isolation would negatively affect the propagation of electrophysiological reactions. To test the influence of BYDV infection on electrophysiological reactions, electropotential waves (EPWs) induced by leaf-tip burning were recorded using aphids as bioelectrodes. EPWs in infected susceptible plants disappeared already after 10 cm in contrast to those in healthy susceptible or infected tolerant or healthy tolerant plants. Another early plant defense reaction is an increase in reactive oxygen species (ROS). Using a fluorescent dye, we found a significant increase in ROS content in infected susceptible plants but not in infected tolerant plants. Similar results were found for the phytohormones abscisic acid and three jasmonates. Salicylic acid levels were generally higher after BYDV infection compared to uninfected plants. Heat stimulation caused an increase in jasmonates. By shedding light on the plant defense mechanisms against BYDV, this study, provides further knowledge for breeding virus tolerant plants. PMID:29563918

  4. Field Performance versus Standard Test Condition Efficiency of Tandem Solar Cells and the Singular Case of Perovskites/Silicon Devices.

    PubMed

    Dupré, Olivier; Niesen, Bjoern; De Wolf, Stefaan; Ballif, Christophe

    2018-01-18

    Multijunction cells may offer a cost-effective route to boost the efficiency of industrial photovoltaics. For any technology to be deployed in the field, its performance under actual operating conditions is extremely important. In this perspective, we evaluate the impact of spectrum, light intensity, and module temperature variations on the efficiency of tandem devices with crystalline silicon bottom cells with a particular focus on perovskite top cells. We consider devices with different efficiencies and calculate their energy yields using field data from Denver. We find that annual losses due to differences between operating conditions and standard test conditions are similar for single-junction and four-terminal tandem devices. The additional loss for the two-terminal tandem configuration caused by current mismatch reduces its performance ratio by only 1.7% when an optimal top cell bandgap is used. Additionally, the unusual bandgap temperature dependence of perovskites is shown to have a positive, compensating effect on current mismatch.

  5. Black leaf streak disease affects starch metabolism in banana fruit.

    PubMed

    Saraiva, Lorenzo de Amorim; Castelan, Florence Polegato; Shitakubo, Renata; Hassimotto, Neuza Mariko Aymoto; Purgatto, Eduardo; Chillet, Marc; Cordenunsi, Beatriz Rosana

    2013-06-12

    Black leaf streak disease (BLSD), also known as black sigatoka, represents the main foliar disease in Brazilian banana plantations. In addition to photosynthetic leaf area losses and yield losses, this disease causes an alteration in the pre- and postharvest behavior of the fruit. The aim of this work was to investigate the starch metabolism of fruits during fruit ripening from plants infected with BLSD by evaluating carbohydrate content (i.e., starch, soluble sugars, oligosaccharides, amylose), phenolic compound content, phytohormones, enzymatic activities (i.e., starch phosphorylases, α- and β-amylase), and starch granules. The results indicated that the starch metabolism in banana fruit ripening is affected by BLSD infection. Fruit from infested plots contained unusual amounts of soluble sugars in the green stage and smaller starch granules and showed a different pattern of superficial degradation. Enzymatic activities linked to starch degradation were also altered by the disease. Moreover, the levels of indole-acetic acid and phenolic compounds indicated an advanced fruit physiological age for fruits from infested plots.

  6. Histopathological changes in rat pancreas after fasting and cassava feeding.

    PubMed

    Geldof, A A; Becking, J L; de Vries, C D; van der Veen, E A

    1992-01-01

    Histopathological changes in rat pancreas were induced by cyclic periods of experimental malnutrition or by cassava (manioc) feeding for 11 weeks. Decline of body weight was correlated with decrease in testicular fat pad weight as a measure of body fat stores. A marked decrease in pancreatic weight in the cassava-fed group was correlated with shrinkage of acinar structures and degenerative features in exocrine pancreas. In the malnutrition group vacuolisation and loss of tissue architecture were observed in some parts of the organ. No signs of ductal obstruction as a tentative cause of pancreatic pathology after malnutrition could be detected. Loss of islets tissue was occasionally seen in degenerative areas. It is concluded that histopathological changes in exocrine pancreas result from malnutrition and cassava feeding differentially and precede ultimate degenerative processes of pancreas endocrine tissue. Tropical malnutrition type diabetes and low protein related diabetes may in their etiology be different entities, but may coincide in practice and aggravate each other to yield severe and irreversible morbidity.

  7. Native yeasts for alternative utilization of overripe mango pulp for ethanol production.

    PubMed

    Buenrostro-Figueroa, Juan; Tafolla-Arellano, Julio C; Flores-Gallegos, Adriana C; Rodríguez-Herrera, Raúl; De la Garza-Toledo, Heliodoro; Aguilar, Cristóbal N

    2017-11-18

    Mango fruits (Mangifera indica L.) are highly perishable, causing postharvest losses and producing agroindustrial waste. In the present work, native yeasts were used to evaluate ethanol production in overripe mango pulp. The two isolated strains showed similar sequences in the 18S rDNA region corresponding to Kluyveromyces marxianus, being different to the data reported in the NCBI database. Values of up to 5% ethanol (w/v) were obtained at the end of fermentation, showing a productivity of 4g/l/day, a yield of up to 49% of ethanol and a process efficiency of 80%. These results represent a viable option for using the surplus production and all the fruits that have suffered mechanical injury that are not marketable and are considered as agroindustrial waste, thus achieving greater income and less postharvest losses. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. 7 CFR 760.637 - Determination of production.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....637 Determination of production. (a) Except for value loss crops, production for the purposes of this... production, including RMA and NAP loss records and yields for insured and noninsured crops. (c) The... production from all harvests. (d) Crop production losses occurring in tropical regions, as defined in part...

  9. 7 CFR 760.637 - Determination of production.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....637 Determination of production. (a) Except for value loss crops, production for the purposes of this... production, including RMA and NAP loss records and yields for insured and noninsured crops. (c) The... production from all harvests. (d) Crop production losses occurring in tropical regions, as defined in part...

  10. 7 CFR 760.637 - Determination of production.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....637 Determination of production. (a) Except for value loss crops, production for the purposes of this... production, including RMA and NAP loss records and yields for insured and noninsured crops. (c) The... production from all harvests. (d) Crop production losses occurring in tropical regions, as defined in part...

  11. 7 CFR 760.637 - Determination of production.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....637 Determination of production. (a) Except for value loss crops, production for the purposes of this... production, including RMA and NAP loss records and yields for insured and noninsured crops. (c) The... production from all harvests. (d) Crop production losses occurring in tropical regions, as defined in part...

  12. 7 CFR 760.637 - Determination of production.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....637 Determination of production. (a) Except for value loss crops, production for the purposes of this... production, including RMA and NAP loss records and yields for insured and noninsured crops. (c) The... production from all harvests. (d) Crop production losses occurring in tropical regions, as defined in part...

  13. Closing the Yield Gap of Sugar Beet in the Netherlands-A Joint Effort.

    PubMed

    Hanse, Bram; Tijink, Frans G J; Maassen, Jurgen; van Swaaij, Noud

    2018-01-01

    The reform of the European Union's sugar regime caused potential decreasing beet prices. Therefore, the Speeding Up Sugar Yield (SUSY) project was initiated. At the start, a 3 × 15 target was formulated: in 2015 the national average sugar yield in the Netherlands equals 15 t/ha (60% of the sugar beet potential) and the total variable costs 15 euro/t sugar beet, aspiring a saving on total variable costs and a strong increase in sugar yield. Based on their average sugar yield in 2000-2004, 26 pairs of "type top" (high yielding) and "type average" (average yielding) growers were selected from all sugar beet growing regions in the Netherlands. On the fields of those farmers, all measures of sugar beet cultivation were investigated, including cost calculation and recording phytopathological, agronomical and soil characteristics in 2006 and 2007. Although there was no significant difference in total variable costs, the "type top" growers yielded significantly 20% more sugar in each year compared to the "type average" growers. Therefore, the most profitable strategy for the growers is maximizing sugar yield and optimizing costs. The difference in sugar yield between growers could be explained by pests and diseases (50%), weed control (30%), soil structure (25%) and sowing date (14%), all interacting with each other. The SUSY-project revealed the effect of the grower's management on sugar yield. As a follow up for the SUSY-project, a growers' guide "Suikerbietsignalen" was published, Best Practice study groups of growers were formed and trainings and workshops were given and field days organized. Further, the benchmarking and feedback on the crop management recordings and the extension on variety choice, sowing performance, foliar fungi control and harvest losses were intensified. On the research part, a resistance breaking strain of the Beet Necrotic Yellow Vein Virus (BNYVV) and a new foliar fungus, Stemphylium beticola , were identified and options for control were tested, and implemented in growers practices. The joint efforts of sugar industry, sugar beet research and growers resulted in a raise in sugar yield from 10.6 t/ha in 2002-2006 to 13.8 t/ha in 2012-2016.

  14. Seasonal temperatures have more influence than nitrogen fertilizer rates on cucumber yield and nitrogen uptake in a double cropping system.

    PubMed

    Guo, Ruiying; Li, Xiaolin; Christie, Peter; Chen, Qing; Zhang, Fusuo

    2008-02-01

    Two-year greenhouse cucumber experiments were conducted to investigate seasonal effects on fruit yield, dry matter allocation, and N uptake in a double-cropping system with different fertilizer management. Seasonal effects were much greater than fertilizer effects, and winter-spring (WS) cucumber attained higher fruit yields and N uptake than autumn-winter (AW) cucumber due to lower cumulative air temperatures during fruit maturation in the AW season. Fertilizer N application and apparent N loss under recommended N management (Nmr) decreased by 40-78% and 33-48% without yield loss compared to conventional N management (Nmt) over four growing seasons. However, there were no seasonal differences in N recommendations, taking into consideration seasonal differences in crop N demand, critical nutrient supply in the root zone and N mineralization rate.

  15. Defense-related proteins involved in sugarcane responses to biotic stress

    PubMed Central

    Souza, Thais P.; Dias, Renata O.; Silva-Filho, Marcio C.

    2017-01-01

    Abstract Sugarcane is one of the most important agricultural crops in the world. However, pathogen infection and herbivore attack cause constant losses in yield. Plants respond to pathogen infection by inducing the expression of several protein types, such as glucanases, chitinases, thaumatins, peptidase inhibitors, defensins, catalases and glycoproteins. Proteins induced by pathogenesis are directly or indirectly involved in plant defense, leading to pathogen death or inducing other plant defense responses. Several of these proteins are induced in sugarcane by different pathogens or insects and have antifungal or insecticidal activity. In this review, defense-related proteins in sugarcane are described, with their putative mechanisms of action, pathogen targets and biotechnological perspectives. PMID:28222203

  16. Efficiency trial of 80% thiophanate-methyl and 72% streptomycin against konjac bacterial soft rot

    NASA Astrophysics Data System (ADS)

    Lin, Tianxing; Gong, Mingfu; Guan, Qinlan; Tan, Chunyan

    2018-04-01

    Amorphophallus konjac soft rot can cause severe yield losses, and the effects agent to prevent the disease had not been found currently in production. In this dissertation, inhibition on konjac soft rot bacteria of seven agricultural fungicides, as benzene ring yl ether, methyl thiophanate, streptomycin sulfate, methane frost hymexazol, bismerthiazol WP, gray mold and Dyson Mn-Zn, was determined by antagonistic petri dish method. The results indicated that: the tested fungicide s had certain inhibition on konjac soft rot bacteria, and the inhibitory effect of different fungicides was significant difference. 80% thiophanate-methyl and 72% streptomycin sulfate had a good inhibitory effect on konjac soft rot disease bacteria.

  17. Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

    PubMed

    Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

    2009-01-01

    Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

  18. The grain drain. Ozone effects on historical maize and soybean yields

    USDA-ARS?s Scientific Manuscript database

    Numerous controlled experiments find that elevated ground-level ozone concentrations ([O3]) damage crops and reduce yield. There have been no estimates of the actual field yield losses in the USA from [O3], even though such estimates would be valuable for projections of future food production and fo...

  19. Rooting traits of peanut genotypes with different yield response to terminal drought

    USDA-ARS?s Scientific Manuscript database

    Drought at pod filling and maturity stages can severely reduce yield of peanut. Better root systems can reduce yield loss from drought. The goal of this study was to investigate the responses to terminal drought of peanut genotypes for root dry weight and root length density. A field experiment was ...

  20. Detecting temporal change in watershed nutrient yields

    Treesearch

    James D. Wickham; Timothy G. Wade; Kurt H. Riitters

    2008-01-01

    Meta-analyses reveal that nutrient yields tend to be higher for watersheds dominated by anthropogenic uses (e.g., urban, agriculture) and lower for watersheds dominated by natural vegetation. One implication of this pattern is that loss of natural vegetation will produce increases in watershed nutrient yields. Yet, the same meta-analyses also reveal that, absent land-...

  1. Detecting Temporal Change in Watershed Nutrient Yields

    Treesearch

    James D. Wickham; Timothy G. Wade; Kurt H. Riitters

    2008-01-01

    Meta-analyses reveal that nutrient yields tend to be higher for watersheds dominated by anthropogenic uses (e.g., urban, agriculture) and lower for watersheds dominated by natural vegetation. One implication of this pattern is that loss of natural vegetation will produce increases in watershed nutrient yields. Yet, the same meta-analyses also reveal that, absent land-...

  2. The impact of tropospheric ozone pollution on trial plot winter wheat yields in Great Britain - an econometric approach.

    PubMed

    Kaliakatsou, Evridiki; Bell, J Nigel B; Thirtle, Colin; Rose, Daniel; Power, Sally A

    2010-05-01

    Numerous experiments have demonstrated reductions in the yields of cereal crops due to tropospheric O(3), with losses of up to 25%. However, the only British econometric study on O(3) impacts on winter wheat yields, found that a 10% increase in AOT40 would decrease yields by only 0.23%. An attempt is made here to reconcile these observations by developing AOT40 maps for Great Britain and matching levels with a large number of standardised trial plot wheat yields from many sites over a 13-year period. Panel estimates (repeated measures on the same plots with time) show a 0.54% decrease in yields and it is hypothesised that plant breeders may have inadvertently selected for O(3) tolerance in wheat. Some support for this is provided by fumigations of cultivars of differing introduction dates. A case is made for the use of econometric as well as experimental studies in prediction of air pollution induced crop loss. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. Stage-specific, Nonlinear Surface Ozone Damage to Rice Production in China

    NASA Astrophysics Data System (ADS)

    Carter, Colin A.; Cui, Xiaomeng; Ding, Aijun; Ghanem, Dalia; Jiang, Fei; Yi, Fujin; Zhong, Funing

    2017-03-01

    China is one of the most heavily polluted nations and is also the largest agricultural producer. There are relatively few studies measuring the effects of pollution on crop yields in China, and most are based on experiments or simulation methods. We use observational data to study the impact of increased air pollution (surface ozone) on rice yields in Southeast China. We examine nonlinearities in the relationship between rice yields and ozone concentrations and find that an additional day with a maximum ozone concentration greater than 120 ppb is associated with a yield loss of 1.12% ± 0.83% relative to a day with maximum ozone concentration less than 60 ppb. We find that increases in mean ozone concentrations, SUM60, and AOT40 during panicle formation are associated with statistically significant yield losses, whereas such increases before and after panicle formation are not. We conclude that heightened surface ozone levels will potentially lead to reductions in rice yields that are large enough to have implications for the global rice market.

  4. Co-pyrolysis characteristics of sawdust and coal blend in TGA and a fixed bed reactor.

    PubMed

    Park, Dong Kyoo; Kim, Sang Done; Lee, See Hoon; Lee, Jae Goo

    2010-08-01

    Co-pyrolysis characteristics of sawdust and coal blend were determined in TGA and a fixed bed reactor. The yield and conversion of co-pyrolysis of sawdust and coal blend based on volatile matters are higher than those of the sum of sawdust and coal individually. Form TGA experiments, weight loss rate of sawdust and coal blend increases above 400 degrees C and additional weight loss was observed at 700 degrees C. In a fixed bed at isothermal condition, the synergy to produce more volatiles is appeared at 500-700 degrees C, and the maximum synergy exhibits with a sawdust blending ratio of 0.6 at 600 degrees C. The gas product yields remarkably increase at lower temperature range by reducing tar yield. The CO yield increases up to 26% at 400 degrees C and CH(4) yield increases up to 62% at 600 degrees C compared with the calculated value from the additive model. (c) 2010 Elsevier Ltd. All rights reserved.

  5. Olive anthracnose: a yield- and oil quality-degrading disease caused by several species of Colletotrichum that differ in virulence, host preference and geographical distribution.

    PubMed

    Talhinhas, Pedro; Loureiro, Andreia; Oliveira, Helena

    2018-03-08

    Olive anthracnose causes fruit rot leading to its drop or mummification, resulting in yield losses and the degradation of oil quality. The disease is caused by diverse species of Colletotrichum, mostly clustering in the C. acutatum species complex. Colletotrichum nymphaeae and C. godetiae are the prevalent species in the Northern Hemisphere, whereas C. acutatum sensu stricto is the most frequent species in the Southern Hemisphere, although it is recently and quickly emerging in the Northern Hemisphere. The disease has been reported from all continents, but it attains higher incidence and severity in the west of the Mediterranean Basin, where it is endemic in traditional orchards of susceptible cultivars. The pathogens are able to survive on vegetative organs. On the fruit surface, infections remain quiescent until fruit maturity, when typical anthracnose symptoms develop. Under severe epidemics, defoliation and death of branches can also occur. Pathogen species differ in virulence, although this depends on the cultivar. The selection of resistant cultivars depends strongly on pathogen diversity and environmental conditions, posing added difficulties to breeding efforts. Chemical disease control is normally achieved with copper-based fungicides, although this may be insufficient under highly favourable disease conditions and causes concern because of the presence of fungicide residues in the oil. In areas in which the incidence is high, farmers tend to anticipate harvest, with consequences in yield and oil characteristics. Olive production systems, harvest and post-harvest processing have experienced profound changes in recent years, namely new training systems using specific cultivars, new harvest and processing techniques and new organoleptic market requests. Changes are also occurring in both the geographical distribution of pathogen populations and the taxonomic framework. In addition, stricter rules concerning pesticide use are likely to have a strong impact on control strategies. A detailed knowledge of pathogen diversity, population dynamics and host-pathogen interactions is basal for the deployment of durable and effective disease control strategies, whether based on resistance breeding, agronomic practices or biological or chemical control. © 2018 BSPP AND JOHN WILEY & SONS LTD.

  6. Osteoporosis affects both post-yield microdamage accumulation and plasticity degradation in vertebra of ovariectomized rats

    NASA Astrophysics Data System (ADS)

    Li, Siwei; Niu, Guodong; Dong, Neil X.; Wang, Xiaodu; Liu, Zhongjun; Song, Chunli; Leng, Huijie

    2017-04-01

    Estrogen withdrawal in postmenopausal women increases bone loss and bone fragility in the vertebra. Bone loss with osteoporosis not only reduces bone mineral density (BMD), but actually alters bone quality, which can be comprehensively represented by bone post-yield behaviors. This study aimed to provide some information as to how osteoporosis induced by estrogen depletion could influence the evolution of post-yield microdamage accumulation and plastic deformation in vertebral bodies. This study also tried to reveal the part of the mechanisms of how estrogen deficiency-induced osteoporosis would increase the bone fracture risk. A rat bilateral ovariectomy (OVX) model was used to induce osteoporosis. Progressive cyclic compression loading was developed for vertebra testing to elucidate the post-yield behaviors. BMD, bone volume fraction, stiffness degradation, and plastic deformation evolution were compared among rats raised for 5 weeks (ovx5w and sham5w groups) and 35 weeks (ovx35w and sham35w groups) after sham surgery and OVX. The results showed that a higher bone loss in vertebral bodies corresponded to lower stiffness and higher plastic deformation. Thus, osteoporosis could increase the vertebral fracture risk probably through microdamage accumulation and plastic deforming degradation.

  7. Non-equilbrium dynamics of ecosystem processes in a changing world

    NASA Astrophysics Data System (ADS)

    Reid, Joseph Pignatello

    The relatively mild and stable climate of the last 10,000 years betrays a history of environmental variability and rapid changes. Humans have recently accelerated global environmental change, ushering in the Anthropocene. Meeting accelerating demands for food, energy, and goods and services has accelerated species extinctions, shows of reactive nitrogen and phosphorus, and warming of the atmosphere. I address the over- arching question of how ecosystems will respond to changing and variable environments through several focused studies. Each study examines an ecosystem response to ex- pected environmental changes in the future. To address how the changing environment affects the sizes and turnover rates of slowly and quickly cycling soil carbon pools, I analyzed the responses of grassland soils to simulated species diversity loss, increased deposition of nitrogen and increased atmospheric CO2. I used a soil respiration experiment to fit models of soil carbon pool turnover to respired carbon dioxide. Species diversity, nitrogen deposition and atmospheric CO2 had no effect on the total soil carbon after 8 years of treatments. Although total soil carbon did not change, the rates of cycling in the fast and slow pools changed in response to elevated CO2 and diversity loss treatments. Nitrogen treatments increased the size of the slowly cycling carbon pool. Precipitation variability has increased around most of the world since the industrial revolution. I used plant mesocosms in a greenhouse experiment to manipulate rainfall variability and mycorrhizal associations. I hypothesized that 1) rewetting events re- sult in higher nitrogen uxes from dry soils than moist soils, 2) a repeated pattern of events caused by low-frequency simulated rainfall results in higher nitrogen uxes and 3) the better ability of ectomycorrhizal fungi relative to arbuscular mycorrhizal fungi to decompose and assimilate organic nitrogen reduces leaching losses of nitrogen caused by both rewetting events and patterns of repeated events. In response to individual rewetting events, drier soils released more nitrate and total nitrogen than wetter soils. Ectomycorrhizal treatments slightly reduced the effect of antecedent soil moisture on total nitrogen and nitrate losses from rewetting events. This supports my hypotheses iii that drier soils release more nitrogen after rainfall events and that ectomycorrhizal asso- ciations can reduce nitrogen losses associated with soil rewetting events. However, only ammonium increased in proportion to the variance in rainfall quantity and mycorrhizal treatments had no effect, largely refuting my hypothesis that soils would release more nitrogen when exposed to higher variability patterns of rainfall. The current pressures that humans place on the environment are only expected to increase as populations and incomes continue to climb. The more than 9 billion peo- ple expected on the planet by 2050 require food, energy, shelter and other goods and services. Historically, producing those benefits has resulted in environmental damage, especially nitrogen pollution through agricultural fertilizers, atmospheric nitrogen de- position and human waste. I developed a model to test the effectiveness of various technologies and strategies to reduce the environmental harms associated with meeting the needs of human well-being. I tested the effects of increased crop yields through genetic gains, increased nutrient efficiency in agricultural systems, reduced meat con- sumption, reduced food waste and improved wastewater treatment on nitrogen yield. The tested levers were mildly effective at reducing nitrogen yield from the baseline busi- ness as usual (BAU) scenario, but still resulted in at least 15% greater nitrogen yield than the present. Applied in combination, in the 'Super Ag' scenario, the levers out performed the sum of their contributions when applied singly. Some levers were more effective in some places than others. Taken together, these results suggest that there is no one solution, and that solutions will be most effective when developed for local conditions and applied in combination.

  8. Reductions in India's crop yield due to ozone

    NASA Astrophysics Data System (ADS)

    Ghude, Sachin D.; Jena, Chinmay; Chate, D. M.; Beig, G.; Pfister, G. G.; Kumar, Rajesh; Ramanathan, V.

    2014-08-01

    This bottom-up modeling study, supported by emission inventories and crop production, simulates ozone on local to regional scales. It quantifies, for the first time, potential impact of ozone on district-wise cotton, soybeans, rice, and wheat crops in India for the first decade of the 21st century. Wheat is the most impacted crop with losses of 3.5 ± 0.8 million tons (Mt), followed by rice at 2.1 ± 0.8 Mt, with the losses concentrated in central and north India. On the national scale, this loss is about 9.2% of the cereals required every year (61.2 Mt) under the provision of the recently implemented National Food Security Bill (in 2013) by the Government of India. The nationally aggregated yield loss is sufficient to feed about 94 million people living below poverty line in India.

  9. Epidemiological features and financial loss due to clinically diagnosed Haemorrhagic Septicemia in bovines in Karnataka, India.

    PubMed

    Govindaraj, G; Krishnamoorthy, P; Nethrayini, K R; Shalini, R; Rahman, H

    2017-09-01

    The epidemiological features and financial losses due to Haemorrhagic Septicemia (HS) in bovines were studied in Karnataka state using the primary data collected from 133 clinically diagnosed HS affected farms. The various losses due to HS and the Benefit- Cost of the vaccination programme in cattle and water buffaloes were studied using mathematical models. The number of HS outbreaks were higher during the year 2002 and peaked during 2005 and thereafter declined due to targeted vaccination against HS. The morbidity and mortality risks were lower in large farms than medium and small farms, and lower in indigenous cattle compared to high yielding crossbred cattle and water buffaloes. The disease occurrence was more in in-milk animals causing serious economic loss to the farmers. Most outbreaks were observed during monsoon season, though the disease was prevalent throughout the year. The mean milk loss per animal was $2, $11 and $50 in indigenous cattle, water buffaloes and crossbred cattle, respectively. In the case of draught animals, the average effective draught power was unavailable for 1.2days/outbreak resulting in a loss of $5 per affected oxen. The treatment and extra labor expenses incurred per animal were $24 and $7, respectively. The average loss per animal due to mortality loss was $275, $284 and $415 in case of indigenous cattle, water buffaloes and crossbred cattle, respectively. The projected loss for the state of Karnataka were $23.89, $17.92 and $11.95 million under high, medium and low HS incidence scenarios, respectively. The Benefit Cost Analysis (BCA) of the vaccination against HS has been estimated at 5.97:1, 4.48:1 and 2.98:1 under high, medium and low incidence scenarios, respectively. The results highlight the important epidemiological features and financial losses to the affected households and the state of Karnataka. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. A contemporary decennial global sample of changing agricultural field sizes

    NASA Astrophysics Data System (ADS)

    White, E.; Roy, D. P.

    2011-12-01

    In the last several hundred years agriculture has caused significant human induced Land Cover Land Use Change (LCLUC) with dramatic cropland expansion and a marked increase in agricultural productivity. The size of agricultural fields is a fundamental description of rural landscapes and provides an insight into the drivers of rural LCLUC. Increasing field sizes cause a subsequent decrease in the number of fields and therefore decreased landscape spatial complexity with impacts on biodiversity, habitat, soil erosion, plant-pollinator interactions, diffusion of disease pathogens and pests, and loss or degradation in buffers to nutrient, herbicide and pesticide flows. In this study, globally distributed locations with significant contemporary field size change were selected guided by a global map of agricultural yield and literature review and were selected to be representative of different driving forces of field size change (associated with technological innovation, socio-economic conditions, government policy, historic patterns of land cover land use, and environmental setting). Seasonal Landsat data acquired on a decadal basis (for 1980, 1990, 2000 and 2010) were used to extract field boundaries and the temporal changes in field size quantified and their causes discussed.

  11. Electron impact fragmentation of thymine: partial ionization cross sections for positive fragments

    NASA Astrophysics Data System (ADS)

    van der Burgt, Peter J. M.; Mahon, Francis; Barrett, Gerard; Gradziel, Marcin L.

    2014-06-01

    We have measured mass spectra for positive ions for low-energy electron impact on thymine using a reflectron time-of-flight mass spectrometer. Using computer controlled data acquisition, mass spectra have been acquired for electron impact energies up to 100 eV in steps of 0.5 eV. Ion yield curves for most of the fragment ions have been determined by fitting groups of adjacent peaks in the mass spectra with sequences of normalized Gaussians. The ion yield curves have been normalized by comparing the sum of the ion yields to the average of calculated total ionization cross sections. Appearance energies have been determined. The nearly equal appearance energies of 83 u and 55 u observed in the present work strongly indicate that near threshold the 55 u ion is formed directly by the breakage of two bonds in the ring, rather than from a successive loss of HNCO and CO from the parent ion. Likewise 54 u is not formed by CO loss from 82 u. The appearance energies are in a number of cases consistent with the loss of one or more hydrogen atoms from a heavier fragment, but 70 u is not formed by hydrogen loss from 71 u.

  12. Recent climate and air pollution impacts on Indian agriculture.

    PubMed

    Burney, Jennifer; Ramanathan, V

    2014-11-18

    Recent research on the agricultural impacts of climate change has primarily focused on the roles of temperature and precipitation. These studies show that India has already been negatively affected by recent climate trends. However, anthropogenic climate changes are a result of both global emissions of long-lived greenhouse gases (LLGHGs) and other short-lived climate pollutants (SLCPs). Two potent SLCPs, tropospheric ozone and black carbon, have direct effects on crop yields beyond their indirect effects through climate; emissions of black carbon and ozone precursors have risen dramatically in India over the past three decades. Here, to our knowledge for the first time, we present results of the combined effects of climate change and the direct effects of SLCPs on wheat and rice yields in India from 1980 to 2010. Our statistical model suggests that, averaged over India, yields in 2010 were up to 36% lower for wheat than they otherwise would have been, absent climate and pollutant emissions trends, with some densely populated states experiencing 50% relative yield losses. [Our point estimates for rice (-20%) are similarly large, but not statistically significant.] Upper-bound estimates suggest that an overwhelming fraction (90%) of these losses is due to the direct effects of SLCPs. Gains from addressing regional air pollution could thus counter expected future yield losses resulting from direct climate change effects of LLGHGs.

  13. Recent climate and air pollution impacts on Indian agriculture

    PubMed Central

    Burney, Jennifer; Ramanathan, V.

    2014-01-01

    Recent research on the agricultural impacts of climate change has primarily focused on the roles of temperature and precipitation. These studies show that India has already been negatively affected by recent climate trends. However, anthropogenic climate changes are a result of both global emissions of long-lived greenhouse gases (LLGHGs) and other short-lived climate pollutants (SLCPs). Two potent SLCPs, tropospheric ozone and black carbon, have direct effects on crop yields beyond their indirect effects through climate; emissions of black carbon and ozone precursors have risen dramatically in India over the past three decades. Here, to our knowledge for the first time, we present results of the combined effects of climate change and the direct effects of SLCPs on wheat and rice yields in India from 1980 to 2010. Our statistical model suggests that, averaged over India, yields in 2010 were up to 36% lower for wheat than they otherwise would have been, absent climate and pollutant emissions trends, with some densely populated states experiencing 50% relative yield losses. [Our point estimates for rice (−20%) are similarly large, but not statistically significant.] Upper-bound estimates suggest that an overwhelming fraction (90%) of these losses is due to the direct effects of SLCPs. Gains from addressing regional air pollution could thus counter expected future yield losses resulting from direct climate change effects of LLGHGs. PMID:25368149

  14. Post-heading heat stress and yield impact in winter wheat of China.

    PubMed

    Liu, Bing; Liu, Leilei; Tian, Liying; Cao, Weixing; Zhu, Yan; Asseng, Senthold

    2014-02-01

    Wheat is sensitive to high temperatures, but the spatial and temporal variability of high temperature and its impact on yield are often not known. An analysis of historical climate and yield data was undertaken to characterize the spatial and temporal variability of heat stress between heading and maturity and its impact on wheat grain yield in China. Several heat stress indices were developed to quantify heat intensity, frequency, and duration between heading and maturity based on measured maximum temperature records of the last 50 years from 166 stations in the main wheat-growing region of China. Surprisingly, heat stress between heading and maturity was more severe in the generally cooler northern wheat-growing regions than the generally warmer southern regions of China, because of the delayed time of heading with low temperatures during the earlier growing season and the exposure of the post-heading phase into the warmer part of the year. Heat stress between heading and maturity has increased in the last decades in most of the main winter wheat production areas of China, but the rate was higher in the south than in the north. The correlation between measured grain yields and post-heading heat stress and average temperature were statistically significant in the entire wheat-producing region, and explained about 29% of the observed spatial and temporal yield variability. A heat stress index considering the duration and intensity of heat between heading and maturity was required to describe the correlation of heat stress and yield variability. Because heat stress is a major cause of yield loss and the number of heat events is projected to increase in the future, quantifying the future impact of heat stress on wheat production and developing appropriate adaptation and mitigation strategies are critical for developing food security policies in China and elsewhere. © 2013 John Wiley & Sons Ltd.

  15. Negative effects of climate warming on maize yield are reversed by the changing of sowing date and cultivar selection in Northeast China.

    PubMed

    Liu, Zhijuan; Hubbard, Kenneth G; Lin, Xiaomao; Yang, Xiaoguang

    2013-11-01

    Northeast China (NEC) accounts for about 30% of the nation's maize production in China. In the past three decades, maize yields in NEC have increased under changes in climate, cultivar selection and crop management. It is important to investigate the contribution of these changing factors to the historical yield increases to improve our understanding of how we can ensure increased yields in the future. In this study, we use phenology observations at six sites from 1981 to 2007 to detect trends in sowing dates and length of maize growing period, and then combine these observations with in situ temperature data to determine the trends of thermal time in the maize growing period, as a measure of changes in maize cultivars. The area in the vicinity of these six sites accounts for 30% of NEC's total maize production. The agricultural production systems simulator, APSIM-Maize model, was used to separate the impacts of changes in climate, sowing dates and thermal time requirements on maize phenology and yields. In NEC, sowing dates trended earlier in four of six sites and maturity dates trended later by 4-21 days. Therefore, the period from sowing to maturity ranged from 2 to 38 days longer in 2007 than it was in 1981. Our results indicate that climate trends alone would have led to a negative impact on maize. However, results from the adaptation assessments indicate that earlier sowing dates increased yields by up to 4%, and adoption of longer season cultivars caused a substantial increase in yield ranging from 13% to 38% over the past 27 years. Therefore, earlier sowing dates and introduction of cultivars with higher thermal time requirements in NEC have overcome the negative effects of climate change and turned what would have otherwise been a loss into a significant increase in maize yield. © 2013 John Wiley & Sons Ltd.

  16. Waterlogging effects on growth and yield components in late-planted soybean.

    PubMed

    Linkemer, G; Board, J E; Musgrave, M E

    1998-01-01

    A major agronomic problem in the southeastern USA is low yield of late-planted soybean [Glycine max (L.) Merr.]. This problem is aggravated by the adverse effect of waterlogging on crop growth. Our objectives were to identify soybean growth stages sensitive to waterlogging; identify yield components and physiological parameters explaining yield losses induced by waterlogging; and determine the extent of yield losses induced by waterlogging under natural field conditions. Greenhouse and field studies were conducted during 1993 and 1994 near Baton Rouge, LA, (30 degrees N Lat) on a Commerce silt loam. Waterlogging tolerance was assessed in cultivar Centennial (Maturity Group VI) at three vegetative and five reproductive growth stages by maintaining the water level at the soil surface in a greenhouse study. Using the same cultivar, we evaluated the effect of drainage in the field for late-planted soybean. Rain episodes determined the timing of waterlogging; redox potential and oxygen concentration of the soil were used to quantify the intensity of waterlogging stress. Results of the greenhouse study indicated that the early vegetative period (V2) and the early reproductive stages (R1, R3, and R5) were most sensitive to waterlogging. Three to 5 cm of rain per day falling on poorly drained soil was sufficient to reduce crop growth rate, resulting in a yield decline from 2453 to 1550 kg ha-1. Yield loss in both field and greenhouse studies was induced primarily by decreased pod production resulting from fewer pods per reproductive node. In conclusion, waterlogging was determined to be an important stress for late-planted soybean in high rainfall areas such as the Gulf Coast Region.

  17. Reducing insecticide use in broad-acre grains production: an Australian study.

    PubMed

    Macfadyen, Sarina; Hardie, Darryl C; Fagan, Laura; Stefanova, Katia; Perry, Kym D; DeGraaf, Helen E; Holloway, Joanne; Spafford, Helen; Umina, Paul A

    2014-01-01

    Prophylactic use of broad-spectrum insecticides is a common feature of broad-acre grains production systems around the world. Efforts to reduce pesticide use in these systems have the potential to deliver environmental benefits to large areas of agricultural land. However, research and extension initiatives aimed at decoupling pest management decisions from the simple act of applying a cheap insecticide have languished. This places farmers in a vulnerable position of high reliance on a few products that may lose their efficacy due to pests developing resistance, or be lost from use due to regulatory changes. The first step towards developing Integrated Pest Management (IPM) strategies involves an increased efficiency of pesticide inputs. Especially challenging is an understanding of when and where an insecticide application can be withheld without risking yield loss. Here, we quantify the effect of different pest management strategies on the abundance of pest and beneficial arthropods, crop damage and yield, across five sites that span the diversity of contexts in which grains crops are grown in southern Australia. Our results show that while greater insecticide use did reduce the abundance of many pests, this was not coupled with higher yields. Feeding damage by arthropod pests was seen in plots with lower insecticide use but this did not translate into yield losses. For canola, we found that plots that used insecticide seed treatments were most likely to deliver a yield benefit; however other insecticides appear to be unnecessary and economically costly. When considering wheat, none of the insecticide inputs provided an economically justifiable yield gain. These results indicate that there are opportunities for Australian grain growers to reduce insecticide inputs without risking yield loss in some seasons. We see this as the critical first step towards developing IPM practices that will be widely adopted across intensive production systems.

  18. Overexpression of an Arabidopsis thaliana galactinol synthase gene improves drought tolerance in transgenic rice and increased grain yield in the field.

    PubMed

    Selvaraj, Michael Gomez; Ishizaki, Takuma; Valencia, Milton; Ogawa, Satoshi; Dedicova, Beata; Ogata, Takuya; Yoshiwara, Kyouko; Maruyama, Kyonoshin; Kusano, Miyako; Saito, Kazuki; Takahashi, Fuminori; Shinozaki, Kazuo; Nakashima, Kazuo; Ishitani, Manabu

    2017-11-01

    Drought stress has often caused significant decreases in crop production which could be associated with global warming. Enhancing drought tolerance without a grain yield penalty has been a great challenge in crop improvement. Here, we report the Arabidopsis thaliana galactinol synthase 2 gene (AtGolS2) was able to confer drought tolerance and increase grain yield in two different rice (Oryza sativa) genotypes under dry field conditions. The developed transgenic lines expressing AtGolS2 under the control of the constitutive maize ubiquitin promoter (Ubi:AtGolS2) also had higher levels of galactinol than the non-transgenic control. The increased grain yield of the transgenic rice under drought conditions was related to a higher number of panicles, grain fertility and biomass. Extensive confined field trials using Ubi:AtGolS2 transgenic lines in Curinga, tropical japonica and NERICA4, interspecific hybrid across two different seasons and environments revealed the verified lines have the proven field drought tolerance of the Ubi:AtGolS2 transgenic rice. The amended drought tolerance was associated with higher relative water content of leaves, higher photosynthesis activity, lesser reduction in plant growth and faster recovering ability. Collectively, our results provide strong evidence that AtGolS2 is a useful biotechnological tool to reduce grain yield losses in rice beyond genetic differences under field drought stress. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  19. Components of a Rice-Oilseed Rape Production System Augmented with Trichoderma sp. Tri-1 Control Sclerotinia sclerotiorum on Oilseed Rape.

    PubMed

    Hu, Xiaojia; Roberts, Daniel P; Xie, Lihua; Maul, Jude E; Yu, Changbing; Li, Yinshui; Zhang, Yinbo; Qin, Lu; Liao, Xing

    2015-10-01

    Sclerotinia sclerotiorum causes serious yield losses on many crops throughout the world. A multicomponent treatment that consisted of the residual rice straw remaining after rice harvest and Trichoderma sp. Tri-1 (Tri-1) formulated with the oilseed rape seedcake fertilizer was used in field soil infested with S. sclerotiorum. This treatment resulted in oilseed rape seed yield that was significantly greater than the nontreated control or when the fungicide carbendizem was used in the presence of this pathogen in field trials. Yield data suggested that the rice straw, oilseed rape seedcake, and Tri-1 components of this treatment all contributed incrementally. Similar treatment results were obtained regarding reduction in disease incidence. Slight improvements in yield and disease incidence were detected when this multicomponent treatment was combined with a fungicide spray. Inhibition of sclerotial germination by this multicomponent treatment trended greater than the nontreated control at 90, 120, and 150 days in field studies but was not significantly different from this control. This multicomponent treatment resulted in increased yield relative to the nontreated control in the absence of pathogen in a greenhouse pot study, while the straw alone and the straw plus oilseed rape seedcake treatments did not; suggesting that Tri-1 was capable of promoting growth. Experiments reported here indicate that a treatment containing components of a rice-oilseed rape production system augmented with Tri-1 can control S. sclerotiorum on oilseed rape, be used in integrated strategies containing fungicide sprays for control of this pathogen, and promote plant growth.

  20. Low acid hydrothermal fractionation of Giant Miscanthus for production of xylose-rich hydrolysate and furfural.

    PubMed

    Kim, Tae Hyun; Ryu, Hyun Jin; Oh, Kyeong Keun

    2016-10-01

    Low acid hydrothermal (LAH) fractionation was developed for the effective recovery of hemicellulosic sugar (mainly xylose) from Miscanthus sacchariflorus Goedae-Uksae 1 (M. GU-1). The xylose yield was maximized at 74.75% when the M. GU-1 was fractionated at 180°C and 0.3wt.% of sulfuric acid for 10min. At this condition, the hemicellulose (mainly xylan) degradation was 86.41%. The difference between xylan degradation and xylose recovery yield, i.e., xylan loss, was 11.66%, as indicated by the formation of decomposed products. The furfural, the value added biochemical product, was also obtained by 0.42g/L at this condition, which was 53.82% of furfural production yield based on the xylan loss. After then, the furfural production continued to increase to a maximum concentration of 1.87g/L, at which point the xylan loss corresponded to 25.87%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Risk assessment of drought disaster in typical area of corn cultivation in China

    NASA Astrophysics Data System (ADS)

    Zhang, Qi; Zhang, Jiquan; Wang, Chunyi

    2017-05-01

    This study assesses the risk of corn drought disaster in China under current climate conditions and builds a predictable relationship between drought disaster risk and yield losses. Two regions, Jilin and Henan, have been selected to represent two typical areas of corn cultivation. Risk is assessed from the aspects of hazard and vulnerability. Hazard presented as drought frequency and intensity. The sensitivity of corn to droughts that happened in different corn-growing stages and regional irrigation ability are used to reflect vulnerability. The results show that drought hazard and sensitivity in Jilin are much more serious than Henan, and irrigation ability is better in Henan. As a result, the drought disaster risk in Jilin is high; corn faces severe drought stress. The average corn yield loss rates during 1978-2010 in Jilin and Henan were 9.94 and 6.91 %, respectively. The correlation between corn yield losses and drought disaster risk is significant ( r = 0.711). The results can help to guide future agriculture planning and drought adaptation polices.

  2. Pyrolysis of tyre powder using microwave thermogravimetric analysis: Effect of microwave power.

    PubMed

    Song, Zhanlong; Yang, Yaqing; Zhou, Long; Zhao, Xiqiang; Wang, Wenlong; Mao, Yanpeng; Ma, Chunyuan

    2017-02-01

    The pyrolytic characteristics of tyre powder treated under different microwave powers (300, 500, and 700 W) were studied via microwave thermogravimetric analysis. The product yields at different power levels were studied, along with comparative analysis of microwave pyrolysis and conventional pyrolysis. The feedstock underwent preheating, intense pyrolysis, and final pyrolysis in sequence. The main and secondary weight loss peaks observed during the intense pyrolysis stage were attributed to the decomposition of natural rubbers and synthetic rubbers, respectively. The total mass loss rates, bulk temperatures, and maximum temperatures were distinctively higher at higher powers. However, the maximum mass loss rate (0.005 s -1 ), the highest yields of liquid product (53%), and the minimum yields of residual solid samples (43.83%) were obtained at 500 W. Compared with conventional pyrolysis, microwave pyrolysis exhibited significantly different behaviour with faster reaction rates, which can decrease the decomposition temperatures of both natural and synthetic rubber by approximately 110 °C-140 °C.

  3. Separating heat stress from moisture stress: analyzing yield response to high temperature in irrigated maize

    NASA Astrophysics Data System (ADS)

    Carter, Elizabeth K.; Melkonian, Jeff; Riha, Susan J.; Shaw, Stephen B.

    2016-09-01

    Several recent studies have indicated that high air temperatures are limiting maize (Zea mays L.) yields in the US Corn Belt and project significant yield losses with expected increases in growing season temperatures. Further work has suggested that high air temperatures are indicative of high evaporative demand, and that decreases in maize yields which correlate to high temperatures and vapor pressure deficits (VPD) likely reflect underlying soil moisture limitations. It remains unclear whether direct high temperature impacts on yields, independent of moisture stress, can be observed under current temperature regimes. Given that projected high temperature and moisture may not co-vary the same way as they have historically, quantitative analyzes of direct temperature impacts are critical for accurate yield projections and targeted mitigation strategies under shifting temperature regimes. To evaluate yield response to above optimum temperatures independent of soil moisture stress, we analyzed climate impacts on irrigated maize yields obtained from the National Corn Growers Association (NCGA) corn yield contests for Nebraska, Kansas and Missouri. In irrigated maize, we found no evidence of a direct negative impact on yield by daytime air temperature, calculated canopy temperature, or VPD when analyzed seasonally. Solar radiation was the primary yield-limiting climate variable. Our analyses suggested that elevated night temperature impacted yield by increasing rates of phenological development. High temperatures during grain-fill significantly interacted with yields, but this effect was often beneficial and included evidence of acquired thermo-tolerance. Furthermore, genetics and management—information uniquely available in the NCGA contest data—explained more yield variability than climate, and significantly modified crop response to climate. Thermo-acclimation, improved genetics and changes to management practices have the potential to partially or completely offset temperature-related yield losses in irrigated maize.

  4. Ensiling of seaweed for a seaweed biofuel industry.

    PubMed

    Herrmann, Christiane; FitzGerald, Jamie; O'Shea, Richard; Xia, Ao; O'Kiely, Pádraig; Murphy, Jerry D

    2015-11-01

    Effective biogas production from seaweed necessitates harvest at times of peak quality of biomass and low-loss preservation for year-around supply. Ensiling of five seaweed species and storage up to 90days was investigated as a method to preserve the methane yield potential. Adequate acidification by natural lactic acid fermentation was difficult due to low rapidly fermentable carbohydrate contents, high buffering capacities and low initial numbers of lactic acid bacteria. Nevertheless, products of silage fermentation increased methane yields by up to 28% and compensated for volatile solid losses during ensiling. Preservation of the original methane yield potential was achieved for four of five seaweed species, provided that silage effluent is collected and utilised. 10-28% of the ensiled biomass was released as effluent with methane yields of 218-423LNkg(-1) VS. If further optimised, ensiling represents an effective method of preservation crucial for an efficient seaweed biofuel industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Phenotypic effects of subclinical paratuberculosis (Johne's disease) in dairy cattle.

    PubMed

    Pritchard, Tracey C; Coffey, Mike P; Bond, Karen S; Hutchings, Mike R; Wall, Eileen

    2017-01-01

    The effect of subclinical paratuberculosis (or Johne's disease) risk status on performance, health, and fertility was studied in 58,096 UK Holstein-Friesian cows with 156,837 lactations across lactations 1 to 3. Low-, medium-, and high-risk group categories were allocated to cows determined by a minimum of 4 ELISA milk tests taken at any time during their lactating life. Lactation curves of daily milk, protein, and fat yields and protein and fat percentage, together with log e -transformed somatic cell count, were estimated using a random regression model to quantify differences between risk groups. The effect of subclinical paratuberculosis risk groups on fertility, lactation-average somatic cell count, and mastitis were analyzed using linear regression fitting risk group as a fixed effect. Milk yield losses associated with high-risk cows compared with low-risk cows in lactations 1, 2, and 3 for mean daily yield were 0.34, 1.05, and 1.61kg; likewise, accumulated 305-d yields were 103, 316, and 485kg, respectively. The total loss was 904kg over the first 3 lactations. Protein and fat yield losses associated with high-risk cows were significant, but primarily a feature of decreasing milk yield. Similar trends were observed for both test-day and lactation-average somatic cell count measures with higher somatic cell counts from medium- and high-risk cows compared with low-risk cows, and differences were in almost all cases significant. Likewise, mastitis incidence was significantly higher in high-risk cows compared with low-risk cows in lactations 2 and 3. Whereas the few significant differences between risk groups among fertility traits were inconsistent with no clear trend. These results are expected to be conservative, as some animals that were considered negative may become positive after the timeframe of this study, particularly if the animal was tested when relatively young. However, the magnitude of milk yield losses together with higher somatic cell counts and an increase in mastitis incidence should motivate farmers to implement the appropriate control measures to reduce the spread of the disease. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Characterization and antagonistic properties of Streptomyces strains isolated from Saharan soils, and evaluation of their ability to control seedling blight of barley caused by Fusarium culmorum.

    PubMed

    Yekkour, A; Sabaou, N; Zitouni, A; Errakhi, R; Mathieu, F; Lebrihi, A

    2012-12-01

    During a screening for potential plant disease control actinomycetes, a total of 133 strains were isolated from Saharan soil samples of seven Algerian regions by dilution technique on chitin-vitamins agar medium. Screening for antagonistic properties using streak assay method showed that 25% of isolates demonstrated strong activities against a wide range of plant pathogenic fungi. Due to their strong anti-Fusarium activities, six of these isolates were selected and subsequently related to Streptomyces species by polyphasic analysis. These isolates were evaluated for their biocontrol ability against Fusarium culmorum, a serious pathogenic fungus of cereals crops related to damping-off and seedling blight resulting in yield loss. Barley seeds were chosen as cereal plant model. Surface bacterized seeds with TW3, RI3 and TW2 strains expressed the highest performances and permit to reduce significantly both the disease occurrence on seedlings (62-76%) and the extent of seedling blight symptoms (over than 95%). However, a negative effect on plant establishment was observed for RI3 treatment. The genus Fusarium is considered to be one of the most problematic phytopathogenic fungi for crop culture worldwide. Inside this genus, F. culmorum is the aetiological agent of seedling blight in various monocotyledonous plants such as barley and cause extensive yield and quality losses in humid and semi-humid regions. Biological control may be a successful alternative to chemical control, particularly with the controversy surrounding the use of the fungicides and the limited obtained results to control F. culmorum. This study highlights the effectiveness of some antagonistic Streptomyces isolated from Algerian Saharan soils to control F. culmorum by the reduction in disease occurrence and disease severity suggesting their use on microbial biocontrol formulation against soilborne diseases. © 2012 The Society for Applied Microbiology.

  7. A Growth and Yield Model for Thinned Stands of Yellow-Poplar

    Treesearch

    Bruce R. Knoebel; Harold E. Burkhart; Donald E. Beck

    1986-01-01

    Simultaneous growth and yield equations were developed for predicting basal area growth and cubic-foot volume growth and yield in thinned stands of yellow-poplar. A joint loss function involving both volume and basal area was used to estimate the coefficients in the system of equations. The estimates obtained were analytically compatible, invariant for projection...

  8. Peanut peg strength and post harvest pod scavenging for full phenotypic yield over digging date and variety

    USDA-ARS?s Scientific Manuscript database

    New peanut cultivars are available with very high yield potential and high levels of disease resistance. With rising input costs and shrinking return margins, all efforts must be made to harvest the full yield produced. Peanut crops are susceptible to high levels of pod loss during digging from a ...

  9. Lumber value loss associated with tapping sugar maples for sap production

    Treesearch

    Paul E. Sendak; Neil K. Huyler; Lawrence D. Garrett

    1982-01-01

    Tapping sugar maples for sap production yields an annual income, but there is a loss in timber quality if the tree is cut for factory lumber products. We estimate an average loss per tree of $2.87 based on a sample of 90 trees in Vermont that were formerly tapped.

  10. Do Plot Scale Studies Yield Useful Data When Assessing Field Scale Practices?

    USDA-ARS?s Scientific Manuscript database

    Plot scale data has been used to develop models used to assess field and watershed scale nutrient losses. The objective of this study was to determine if phosphorus (P) loss results from plot scale rainfall simulation studies are “directionally correct” when compared to field scale P losses. Two fie...

  11. The stochastic resonance for the incidence function model of metapopulation

    NASA Astrophysics Data System (ADS)

    Li, Jiang-Cheng; Dong, Zhi-Wei; Zhou, Ruo-Wei; Li, Yun-Xian; Qian, Zhen-Wei

    2017-06-01

    A stochastic model with endogenous and exogenous periodicities is proposed in this paper on the basis of metapopulation dynamics to model the crop yield losses due to pests and diseases. The rationale is that crop yield losses occur because the physiology of the growing crop is negatively affected by pests and diseases in a dynamic way over time as crop both grows and develops. Metapopulation dynamics can thus be used to model the resultant crop yield losses. The stochastic metapopulation process is described by using the Simplified Incidence Function model (IFM). Compared to the original IFMs, endogenous and exogenous periodicities are considered in the proposed model to handle the cyclical patterns observed in pest infestations, diseases epidemics, and exogenous affecting factors such as temperature and rainfalls. Agricultural loss data in China are used to fit the proposed model. Experimental results demonstrate that: (1) Model with endogenous and exogenous periodicities is a better fit; (2) When the internal system fluctuations and external environmental fluctuations are negatively correlated, EIL or the cost of loss is monotonically increasing; when the internal system fluctuations and external environmental fluctuations are positively correlated, an outbreak of pests and diseases might occur; (3) If the internal system fluctuations and external environmental fluctuations are positively correlated, an optimal patch size can be identified which will greatly weaken the effects of external environmental influence and hence inhibit pest infestations and disease epidemics.

  12. Drought Induced Changes in Growth, Osmolyte Accumulation and Antioxidant Metabolism of Three Maize Hybrids

    PubMed Central

    Anjum, Shakeel A.; Ashraf, Umair; Tanveer, Mohsin; Khan, Imran; Hussain, Saddam; Shahzad, Babar; Zohaib, Ali; Abbas, Farhat; Saleem, Muhammad F.; Ali, Iftikhar; Wang, Long C.

    2017-01-01

    Consequences of drought stress in crop production systems are perhaps more deleterious than other abiotic stresses under changing climatic scenarios. Regulations of physio-biochemical responses of plants under drought stress can be used as markers for drought stress tolerance in selection and breeding. The present study was conducted to appraise the performance of three different maize hybrids (Dong Dan 80, Wan Dan 13, and Run Nong 35) under well-watered, low, moderate and SD conditions maintained at 100, 80, 60, and 40% of field capacity, respectively. Compared with well-watered conditions, drought stress caused oxidative stress by excessive production of reactive oxygen species (ROS) which led to reduced growth and yield formation in all maize hybrids; nevertheless, negative effects of drought stress were more prominent in Run Nong 35. Drought-induced osmolyte accumulation and strong enzymatic and non-enzymatic defense systems prevented the severe damage in Dong Dan 80. Overall performance of all maize hybrids under drought stress was recorded as: Dong Dan 80 > Wan Dan 13 > Run Nong 35 with 6.39, 7.35, and 16.55% yield reductions. Consequently, these biochemical traits and differential physiological responses might be helpful to develop drought tolerance genotypes that can withstand water-deficit conditions with minimum yield losses. PMID:28220130

  13. Loss of photosynthetic efficiency in the shade. An Achilles heel for the dense modern stands of our most productive C4 crops?

    PubMed Central

    Pignon, Charles P.; Jaiswal, Deepak; McGrath, Justin M.

    2017-01-01

    Abstract The wild progenitors of major C4 crops grew as individuals subjected to little shading. Today they are grown in dense stands where most leaves are shaded. Do they maintain photosynthetic efficiency in these low light conditions produced by modern cultivation? The apparent maximum quantum yield of CO2 assimilation (ΦCO2max,app), a key determinant of light-limited photosynthesis, has not been systematically studied in field stands of C4 crops. ΦCO2max,app was derived from the initial slope of the response of leaf CO2 uptake (A) to photon flux (Q). Leaf fractional light absorptance (α) was measured to determine the absolute maximum quantum yield of CO2 assimilation on an absorbed light basis (ΦCO2max,abs). Light response curves were determined on sun and shade leaves of 49 field plants of Miscanthus × giganteus and Zea mays following canopy closure. ΦCO2max,app and ΦCO2max,abs declined significantly by 15–27% (P<0.05) with canopy depth. Experimentally, leaf age was shown unlikely to cause this loss. Modeling canopy CO2 assimilation over diurnal courses suggested that the observed decline in ΦCO2max,app with canopy depth costs 10% of potential carbon gain. Overcoming this limitation could substantially increase the productivity of major C4 crops. PMID:28110277

  14. The drought risk of maize in the farming-pastoral ecotone in Northern China based on physical vulnerability assessment

    NASA Astrophysics Data System (ADS)

    Wang, Zhiqiang; Jiang, Jingyi; Ma, Qing

    2016-12-01

    Climate change is affecting every aspect of human activities, especially the agriculture. In China, extreme drought events caused by climate change have posed a great threat to food safety. In this work we aimed to study the drought risk of maize in the farming-pastoral ecotone in Northern China based on physical vulnerability assessment. The physical vulnerability curve was constructed from the relationship between drought hazard intensity index and yield loss rate. The risk assessment of agricultural drought was conducted from the drought hazard intensity index and physical vulnerability curve. The probability distribution of drought hazard intensity index decreased from south-west to north-east and increased from south-east to north-west along the rainfall isoline. The physical vulnerability curve had a reduction effect in three parts of the farming-pastoral ecotone in Northern China, which helped to reduce drought hazard vulnerability on spring maize. The risk of yield loss ratio calculated based on physical vulnerability curve was lower compared with the drought hazard intensity index, which suggested that the capacity of spring maize to resist and adapt to drought is increasing. In conclusion, the farming-pastoral ecotone in Northern China is greatly sensitive to climate change and has a high probability of severe drought hazard. Risk assessment of physical vulnerability can help better understand the physical vulnerability to agricultural drought and can also promote measurements to adapt to climate change.

  15. SPATIAL HETEROGENEITY OF PHOTOSYNTHETIC ACTIVITY WITHIN DISEASED CORALS FROM THE GREAT BARRIER REEF(1).

    PubMed

    Roff, George; Ulstrup, Karin E; Fine, Maoz; Ralph, Peter J; Hoegh-Guldberg, Ove

    2008-04-01

    Morphological diagnosis and descriptions of seven disease-like syndromes affecting scleractinian corals were characterized from the southern Great Barrier Reef (GBR). Chl a fluorescence of PSII was measured using an Imaging-PAM (pulse amplitude modulated) fluorometer, enabling visualization of the two-dimensional variability in the photophysiology of endosymbiotic dinoflagellates (zooxanthellae) by measuring rapid light curves. Three of four syndromes associated with active tissue loss (type a) were spatially homogenous (white syndrome, brown band, and skeletal eroding band), with no impact on the photochemical function of zooxanthellae populations at or behind the lesion borders. However, a decline in maximum quantum yield (Fv /Fm ) and elevated levels of maximum nonphotochemical quenching (NPQmax ) occurred in visually healthy tissue of black band disease adjacent to the lesion borders, possibly due to hypoxic conditions caused by the black band cyanobacterial mat. Two out of three syndromes associated with pathological change of intact tissue with no active tissue loss (type b) showed variable photophysiological responses (neoplasia and pigmentation response). Only the bleached foci associated with white patch syndrome appeared to impact primarily on the symbiotic dinoflagellates, as evidenced by declines in minimum fluorescence (F0 ) and maximum quantum yield (Fv /Fm ), with no indication of degeneration in the host tissues. Our results suggest that for the majority of coral syndromes from the GBR, pathogenesis occurs in the host tissue, while the impact on the zooxanthellae populations residing in affected corals is minimal. © 2008 Phycological Society of America.

  16. Visual loss in Takayasu Arteritis - Look Beyond the Eye.

    PubMed

    Peter, Jayanthi; Joseph, George; Mathew, Vivek; Peter, John Victor

    2014-08-01

    Patients with Takayasu arteritis often present with reduced vision related either to the disease per se or due to complications of therapy. We report a patient with Takayasu arteritis who developed acute onset bilateral visual loss 6wks following percutaneous revascularization of occluded aortic arch branches. No ocular cause for the visual loss was evident. The reason for visual loss in this patient was an extraocular cause. Ocular and extraocular causes of visual loss in Takayasu arteritis are discussed.

  17. The judged seriousness of an environmental loss is a matter of what caused it

    Treesearch

    Thomas C. Brown; George L. Peterson; R. Marc Brodersen; Valerie Ford; Paul A. Bell

    2005-01-01

    Environmental losses, each described along with its cause, were judged for seriousness. Four types of cause were studied: illegal behavior, carelessness, economic and population growth, and natural events. Identical environmental losses (e.g., of a herd of elk or a large stand of trees) were considered most serious when caused by illegal behavior or carelessness, and...

  18. In vivo phosphoproteome characterization reveals key starch granule-binding phosphoproteins involved in wheat water-deficit response.

    PubMed

    Chen, Guan-Xing; Zhen, Shou-Min; Liu, Yan-Lin; Yan, Xing; Zhang, Ming; Yan, Yue-Ming

    2017-10-23

    Drought stress during grain development causes significant yield loss in cereal production. The phosphorylated modification of starch granule-binding proteins (SGBPs) is an important mechanism regulating wheat starch biosynthesis. In this study, we performed the first proteomics and phosphoproteomics analyses of SGBPs in elite Chinese bread wheat (Triticum aestivum L.) cultivar Jingdong 17 under well-watered and water-stress conditions. Water stress treatment caused significant reductions in spike grain numbers and weight, total starch and amylopectin content, and grain yield. Two-dimensional gel electrophoresis revealed that the quantity of SGBPs was reduced significantly by water-deficit treatment. Phosphoproteome characterization of SGBPs under water-deficit treatment demonstrated a reduced level of phosphorylation of main starch synthesis enzymes, particularly for granule-bound starch synthase (GBSS I), starch synthase II-a (SS II-a), and starch synthase III (SS III). Specifically, the Ser34 site of the GBSSI protein, the Tyr358 site of SS II-a, and the Ser837 site of SS III-a exhibited significant less phosphorylation under water-deficit treatment than well-watered treatment. Furthermore, the expression levels of several key genes related with starch biosynthesis detected by qRT-PCR were decreased significantly at 15 days post-anthesis under water-deficit treatment. Immunolocalization showed a clear movement of GBSS I from the periphery to the interior of starch granules during grain development, under both water-deficit and well-watered conditions. Our results demonstrated that the reduction in gene expression or transcription level, protein expression and phosphorylation levels of starch biosynthesis related enzymes under water-deficit conditions is responsible for the significant decrease in total starch content and grain yield.

  19. Satellite-based studies of maize yield spatial variations and their causes in China

    NASA Astrophysics Data System (ADS)

    Zhao, Y.

    2013-12-01

    Maize production in China has been expanding significantly in the past two decades, but yield has become relatively stagnant in the past few years, and needs to be improved to meet increasing demand. Multiple studies found that the gap between potential and actual yield of maize is as large as 40% to 60% of yield potential. Although a few major causes of yield gap have been qualitatively identified with surveys, there has not been spatial analysis aimed at quantifying relative importance of specific biophysical and socio-economic causes, information which would be useful for targeting interventions. This study analyzes the causes of yield variation at field and village level in Quzhou county of North China Plain (NCP). We combine remote sensing and crop modeling to estimate yields in 2009-2012, and identify fields that are consistently high or low yielding. To establish the relationship between yield and potential factors, we gather data on those factors through a household survey. We select targeted survey fields such that not only both extremes of yield distribution but also all soil texture categories in the county is covered. Our survey assesses management and biophysical factors as well as social factors such as farmers' access to agronomic knowledge, which is approximated by distance to the closest demonstration plot or 'Science and technology backyard'. Our survey covers 10 townships, 53 villages and 180 fields. Three to ten farmers are surveyed depending on the amount of variation present among sub pixels of each field. According to survey results, we extract the amount of variation within as well as between villages and or soil type. The higher within village or within field variation, the higher importance of management factors. Factors such as soil type and access to knowledge are more represented by between village variation. Through regression and analysis of variance, we gain more quantitative and thorough understanding of causes to yield variation at village scale, which further explains the gap between average and highest achieved yield.

  20. Effect of Integrated Water-Nutrient Management Strategies on Soil Erosion Mediated Nutrient Loss and Crop Productivity in Cabo Verde Drylands

    PubMed Central

    Baptista, Isaurinda; Ritsema, Coen; Geissen, Violette

    2015-01-01

    Soil erosion, runoff and related nutrient losses are a big risk for soil fertility in Cabo Verde drylands. In 2012, field trials were conducted in two agro-ecological zones to evaluate the effects of selected techniques of soil-water management combined with organic amendments (T1: compost/manure + soil surfactant; T2: compost/animal or green manure + pigeon-pea hedges + soil surfactant; T3: compost/animal or green manure + mulch + pigeon-pea hedges) on nitrogen (N) and phosphorus (P) losses in eroded soil and runoff and on crop yields. Three treatments and one control (traditional practice) were tested in field plots at three sites with a local maize variety and two types of beans. Runoff and eroded soil were collected after each erosive rain, quantified, and analysed for NO3-N and PO4-P concentrations. In all treatments runoff had higher concentrations of NO3-N (2.20-4.83 mg L-1) than of PO4-P (0.02-0.07 mg L-1), and the eroded soil had higher content of PO4-P (5.27-18.8 mg g-1) than of NO3-N (1.30-8.51 mg g-1). The control had significantly higher losses of both NO3-N (5.4, 4.4 and 19 kg ha-1) and PO4-P (0.2, 0.1 and 0.4 kg ha-1) than the other treatments. T3 reduced soil loss, runoff and nutrient losses to nearly a 100% while T1 and T2 reduced those losses from 43 to 88%. The losses of NO3-N and PO4-P were highly correlated with the amounts of runoff and eroded soil. Nutrient losses from the applied amendments were low (5.7% maximum), but the losses in the control could indicate long-term nutrient depletion in the soil (19 and 0.4 kg ha-1 of NO3-N and PO4-P, respectively). T1-T3 did not consistently increase crop yield or biomass in all three sites, but T1 increased both crop yield and biomass. We conclude that T3 (combining crop-residue mulch with organic amendment and runoff hedges) is the best treatment for steep slope areas but, the pigeon-pea hedges need to be managed for higher maize yield. T1 (combining organic amendment with soil surfactant) could be a better choice for flatter areas with deeper soils. PMID:26230549

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