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Migratory flight of insect pests within a year-round distribution: European corn borer as a case study

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Journal of Integrative agriculture 2018年第7期17卷 1485-1505页

作者： Thomas W.Sappington Corn Insects and Crop genetics research unit Agricultural Research ServiceUSDA

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not searching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops are long-distance migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but seasonally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resistance management. As a case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of understanding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.

关键词： migration dispersal flight movement ecology European corn borer Ostrinia nubilalis

An Adaptive Sequential Replacement Method for Variable Selection in Linear Regression Analysis

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Open Journal of Statistics 2023年第5期13卷 746-760页

作者： Jixiang Wu Johnie N. Jenkins Jack C. McCarty Jr. genetics and sustainable agriculture research unit USDA-ARS Mississippi State USA

With the rapid development of DNA technologies, high throughput genomic data have become a powerful leverage to locate desirable genetic loci associated with traits of importance in various crop species. However, current genetic association mapping analyses are focused on identifying individual QTLs. This study aimed to identify a set of QTLs or genetic markers, which can capture genetic variability for marker-assisted selection. Selecting a set with k loci that can maximize genetic variation out of high throughput genomic data is a challenging issue. In this study, we proposed an adaptive sequential replacement (ASR) method, which is considered a variant of the sequential replacement (SR) method. Through Monte Carlo simulation and comparing with four other selection methods: exhaustive, SR method, forward, and backward methods we found that the ASR method sustains consistent and repeatable results comparable to the exhaustive method with much reduced computational intensity.

关键词： Adaptive Sequential Replacement Association Mapping Exhaustive Method Global Optimal Solution Sequential Replacement Variable Selection

Evaluating the impacts of converting grain to vegetable fields on nitrate transport in the deep vadose zone of the North China Plain

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Journal of Geographical Sciences 2025年第1期 189-212页

作者： LIU Meiying MIN Leilei WU Lin ZHANG Yucui QI Yongqing WANG Shiqin LIU Binbin GENG Di SHEN Yanjun Hebei Key Laboratory of Water-Saving agriculture Key Laboratory of Agricultural Water ResourcesCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyCAS School of Advanced Agricultural Sciences University of Chinese Academy of Sciences

Nitrate （NO3-） accumulation and transport processes in the thick vadose zone affect the evolution of the groundwater NO3-content in intensive agricultural *** land-use change （ALUC）,typically accompanied by substantial alterations in nitrogen fertilizer application and irrigation practices,is an important influencing *** study evaluated the changes in NO3-accumulation and transport in the deep vadose zone （DVZ,below the root zone）,and the groundwater NO3-content associated with ALUC from grain to vegetable fields in the North China Plain （NCP）.The ALUC from grain to vegetable resulted in nitrate–nitrogen （NO3--N） accumulation in DVZ increased by 235.5 kg ha-1m-1（163.2%） in the piedmont plain and 224.9 kg ha-1m-1（102.7%） in the central plain,*** change accelerated downward transport velocity in the DVZ (from 0.81±0.47 to 0.89±0.55 m yr-1in the piedmont plain,and from 0.24±0.12 to 0.92±0.12 m yr-1in the central plain) and increased NO3-leaching *** transport velocity and leaching fluxes resulted in chemical N-fertilizer entering the aquifer in several areas in the piedmont *** impact of the agricultural activity intensity changes,accompanied by the ALUC,on groundwater quantity and quality should be considered in similar regions.

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Characterization and transcriptional analyses of cDNAs encoding three trypsin- and chymotrypsin-like proteinases in CrylAb-susceptible and CrylAb-resistant strains of sugarcane borer, Diatraea saccharalis

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Insect Science 2013年第4期20卷 485-496页

作者： Yunlong Yang Yu Cheng Zhu James Ottea Claudia Husseneder B. Rogers Leonard Craig Abel Randall Luttrell Fangneng Huang Department of Entomology Louisiana State University Agricultural Center Baton Rouge Louisiana Southern Insect Management research unit Agricultural Research Service United States Department of Agriculture Stoneville Mississippi Corn Insects and Crop genetics research unit Agricultural Research Service United States Department of Agriculture Ames Iowa USA

Diatraea saccharalis is a major corn borer pest. Midgut serine proteinases are essential for insect growth and development. Alteration of midgut proteinases is re- sponsible for Bt resistance development in some species. To clone midgut trypsin and chymotrypsin cDNAs and to test if the CrylAb resistance in D. saccharalis is associ- ated with changes in midgut proteinases, total midgut tryptic and chymotryptic activities, cDNA sequences, and gene expressions of three trypsin and three chymotrypsin genes were comparatively examined between Cry 1 Ab-susceptible （Cry 1 Ab- S S） and Cry 1 Ab-resistant （Cry 1 Ab-RR） strains. Full-length cDNAs encoding three trypsin- and three chymotrypsin- like proteinases were sequenced from CrylAb-SS and CrylAb-RR larvae. These cDNAs code for active forms of midgut serine proteinases with all fimctional motifs, includ- ing signal peptide, conserved His-Asp-Ser for the catalytic triad, three pairs of cysteines for disulfide bridge configurations, and conserved substrate specificity determination residues. In general, cDNA and putative protein sequences are highly similar between CrylAb-SS and CrylAb-RR strains, except for a few nucleotide and predicted amino acid substitutions, whose function need to be further clarified. Total trypsin and chymotrypsin activities were also similar between CrylAb-SS and CrylAb-RR strains. Transcriptional levels of the trypsin and chymotrypsin genes had numerical difference between Cry 1 Ab-SS and CrylAb-RR strains, but the difference was not statistically significant. Data suggest that the development of CrylAb resistance in D. saccharalis was not significantly as- sociated with these trypsins and chymotrypsins. Results clarified the role of six midgut proteinases and provided a foundation for continuing examination of potential involvement of other midgut proteinases in Bt resistance development and other important biochemical processes.

关键词： Bt cDNA chymotrypsin enzymatic activity resistance trypsin

Evaluation of Moving Grid Adjustment (MGA) Method in Field Variation Control

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Open Journal of Statistics 2024年第5期14卷 450-466页

作者： Jixiang Wu Johnie N. Jenkins Jack C. McCarty genetics and sustainable agriculture research unit USDA-ARS Mississippi State MS USA

Spatial variation is often encountered when large scale field trials are conducted which can result in biased estimation or prediction of treatment (i.e. genotype) values. An effective removal of spatial variation is needed to ensure unbiased estimation or prediction and thus increase the accuracy of field data evaluation. A moving grid adjustment (MGA) method, which was proposed by Technow, was evaluated through Monte Carlo simulation for its statistical properties regarding field spatial variation control. Our simulation results showed that the MGA method can effectively account for field spatial variation if it does exist;however, this method will not change phenotype results if field spatial variation does not exist. The MGA method was applied to a large-scale cotton field trial data set with two representative agronomic traits: lint yield (strong field spatial pattern) and lint percentage (no field spatial pattern). The results suggested that the MGA method was able to effectively separate the spatial variation including blocking effects from random error variation for lint yield while the adjusted data remained almost identical to the original phenotypic data. With application of the MGA method, the estimated variance for residuals was significantly reduced (62.2% decrease) for lint yield while more genetic variation (29.7% increase) was detected compared to the original data analysis subject to the conventional randomized complete block design analysis. On the other hand, the results were almost identical for lint percentage with and without the application of the MGA method. Therefore, the MGA method can be a useful addition to enhance data analysis when field spatial pattern exists.

关键词： Spatial Variation Linear Mixed Model Approach Experimental Design Moving Grid Adjustment Crop Trial

Anaerobic soil disinfestation:A chemical-independent approach to pre-plant control of plant pathogens

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Journal of Integrative agriculture 2015年第11期14卷 2309-2318页

作者： S L Strauss D A Kluepfel USDA-ARS Crops Pathology and genetics research unit University of California

Due to increasing regulations and restrictions, there is an urgent need to develop effective alternatives to chemical-dependent fumigation control of soilborne pests and pathogens. Anaerobic soil disinfestation （ASD） is one such alternative showing great promise for use in the control of soilborne pathogens and pests. This method involves the application of a carbon source, irrigation to field capacity, and covering the soil with a plastic tarp. While the mechanisms of ASD are not completely understood, they appear to be a combination of changes in the soil microbial community composition, production of volatile organic compounds, and the generation of lethal anaerobic conditions. The variety of materials and options for ASD application, including carbon sources, soil temperature, and plastic tarp type, influence the efficacy of pathogen sup- pression and disease control. Currently, both dry （e.g., rice bran） and liquid （e.g., ethanol） carbon sources are commonly used, but with different results depending on environmental conditions. While solarization is not an essential component of ASD, it can enhance efficacy. Understanding the mechanisms that mediate biological changes occurring in the soil during ASD will facilitate our ability to increase ASD efficacy while enhancing its commercial viability.

关键词： anaerobic soil disinfestation biological soil disinfestation soilborne pathogens fumigation

Influence of Diazotrophic Bacteria on Antioxidant Enzymes and Some Biochemical Characteristics of Soybean Subjected to Water Stress

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Journal of Integrative agriculture 2012年第11期11卷 1828-1835页

作者： Hamed Zakikhani Mohammad RezaArdakani Farhad Rejali Majid Gholamhoseini Aydin Khodaei Joghan Aria Dolatabadian Division of sustainable agriculture Agricultural Research CenterIslamic Azad University Karaj Branch Soil and Water research Institute Agronomy Department Faculty of AgricultureTarbiat Modares University

Drought stress is an abiotic stress that imposes serious constraints on plants. The present investigation was carried out to determine the inter-relationship between some physiological attributes of soybeans affected by drought stress and pure isolates ofAzotobacter andAzospirillum. Drought stress and bacterial application increased catalase and glutathione peroxidase activity, whereas drought stress increased superoxide dismutase activity during the pod-filling stage. Abscisic acid and proline levels increased due to drought stress and bacterial application during the flowering stage, whereas total plant nitrogen was enhanced under well-watered conditions when plants were inoculated with bacteria. The close relationship between enzyme activity and drought stress with bacteria indicated that antioxidant enzymes play an important role in alleviating the detrimental effects of water stress. In addition, the enhancement of abscisic acid and proline could be positively linked with drought stress, and drought-induced abscisic acid could induce proline accumulation and the expression of antioxidant enzyme genes.

关键词： abscisic acid Azospirillum Azotobacter proline soybean water stress

Brief review on climate change and tropical peatlands

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Geoscience Frontiers 2019年第2期10卷 373-380页

作者： Lee Yit Leng Osumanu Haruna Ahmed Mohamadu Boyie Jalloh Department of Mechanical Engineering Technology Faculty of Engineering TechnologyUniversiti Malaysia PerlisKampus Uniciti Alam Department of Crop Science Faculty of Agriculture and Food SciencesUniversiti Putra Malaysia Bintulu Sarawak Campus agriculture and Environment Borneo Eco-Science Research CenterFaculty of Agriculture and Food SciencesUniversiti Putra Malaysia Bintulu Sarawak Campus Institute of Tropical agriculture and Food Security Universiti Putra Malaysia Crop Production Programme Faculty of Sustainable AgricultureUniversiti Malaysia Sabah sustainable Palm Oil research unit (SPOR) Faculty of Sustainable AgricultureUniversiti Malaysia Sabah

In 2008, the very extensive tropical peats were estimated to be about 182 million ha spanning South America, Asia and Africa. About 20.3%(36.9 million ha) of this area exist in Asia. Peats are classified based on their degree of decomposition, namely Fibrists, Hemists, Saprists and Folists. This makes them different in characteristics. The activities of microorganisms vary in different types of peat due to, for example, the sapric layer of well humified peat can provide water and food to microorganisms during heat stress. In another scenario, deeper peat is older and typically has lower levels of labile carbon to provide substrate for microbes compared to surface peat. A complete understanding of the microbial communities in different layers of peat is essential as microorganisms play major roles in peat decomposition and are important to ecosystem processes. These peats are a very important global carbon(C)store or reserve and could severely impact climate change if not managed well. Peatlands can store as much as 40 to 90 Gt C. Mis-management of peats could severely impact the environment particularly the emission of carbon into the atmosphere. For instance, clearing of peatlands using fire has been reported to release an estimated 88 t C ha^(-1) to the atmosphere. There are several factors which influence the environmental consequences of tropical peat especially in relation to climate change. The main influences are:(i) changes in temperature,(ii) changes in precipitation or rainfall,(iii) changes in atmospheric composition, and(iv) fire and haze. This paper is a brief review on these four influences in relation to climate change. It is apparent from the brief review that there is a need for continued short and long-term research to better understand tropical peats and how they affect our climate. This will hopefully provide the basis for predicting better what could happen under various scenarios.

关键词： Tropical peats Climate change Carbon Methane Decomposition Microorganisms

Adsorption of avermectins on activated carbon: Equilibrium, kinetics, and UV-shielding

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中国有色金属学会会刊：英文版 2009年第S3期19卷 845-850页

作者：顾微孙长娇刘琪崔海信 Institute of Environment and sustainable Developmentin agriculture Chinese Academy of Agricultural Sciences

The adsorption of biopesticide avermectins onto activated carbon from ethanol solution with different initial concentrations at 303.15 K was performed. The obtained equilibrium and kinetic data of the adsorption process were assayed to evaluate the adsorption potential of activated carbon for avermectins. The results show that the activated carbon is effective for the adsorption of avermectins. Moreover, the adsorption of avermectins onto activated carbon agrees with Langmuir isotherm model, while pseudo-second-order kinetics model is better fitable for such adsorption process. In addition, activated carbon can efficiently protect adsorbed avermectins from photodegradation.

关键词： activated carbon avermectins adsorption UV-shielding