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Understanding temporal stability:a long-term analysis of usda ars watersheds

International Journal of Digital Earth 2021年第10期14卷 1243-1254页

作者： Evan J.Coopersmith Michael H.Cosh Patrick J.Starks David D.Bosch Chandra Holifield Collins Mark Seyfried Stan Livingston John Prueger Soil Insight LLCWashington D.C.USA usda-Agricultural Research Service Beltsville Agricultural Research CenterHydrology and Remote Sensing LaboratoryBeltsvilleUSA usda-Agricultural Research Service-Grazinglands Research Laboratory El RenoUSA usda-Agricultural Research Service-Southeast Watershed Research Laboratory TiftonUSA usda-Agricultural Research Service-Southwest Watershed Research Center TucsonUSA usda-Agricultural Research Service-Northwest Watershed Research Laboratory BoiseUSA usdaAgricultural Research Service-National Soil Erosion Research Laboratory West LafayetteUSA usda-Agricultural Research Service-National Laboratory for Agriculture and Environment AmesUSA

The *** of Agriculture’s Agricultural Research Service(usdaars)maintains seven in situ soil moisture networks throughout the continental United States,some since *** networks are crucial for understanding the spatial and temporal extent of droughts in their historical context,parameterization of hydrologic models,and local agricultural decision ***,the estimates from these networks are dependent upon their ability to provide reliable soil moisture information at a large *** is also not known how many network stations are sufficient to monitor watershed scale ***,the objectives of this research were to:(1)determine how temporally stable these networks are,including the relationships between various sensors on a year-to-year and seasonal basis,and(2)attempt to determine how many sensors are required,within a network,to approximate the full network *** data from seven in situ,it is concluded that approximately 12 soil moisture sensors are sufficient in most environments,presuming their locations are distributed to capture the hydrologic heterogeneity of the *** is possible to install a temporary network containing a suitable number of sensors for an appropriate length of time,glean stable relationships between locations,and retain these insights moving forward with fewer sensor resources.

关键词： Soil moisture temporal stability in situ networks

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Development of a PWM Precision Spraying Controller for Unmanned Aerial Vehicles

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Journal of Bionic Engineering 2010年第3期7卷 276-283页

作者： W.Clint Hoffmann Brad Fritz usda-ars College Station

This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PWMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PWM controller was tested and validated using LabVIEW8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PWM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.

关键词： PWM controller TL494 precision spraying UAV

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Mineral concentrations of chickpea and lentil cultivars and breeding lines grown in the *** Northwest

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The Crop Journal 2018年第3期6卷 253-262页

作者： George J.VANDemark Michael A.Grusak Rebecca J.Mc Gee usda-ars Grain Legume Genetics and Physiology Research Unit usda-ars Red River Valley Agricultural Research Center

Diseases and health complications caused by mineral deficiencies afflict billions of people globally. Developing pulse crops with elevated seed mineral concentrations can contribute to reducing the incidence of these deficiencies. The objectives of this study were to estimate variance components conditioning seed mineral concentrations of chickpea and lentil grown in Washington and Idaho, determine correlations between different mineral concentrations and between mineral concentrations and yield, 100-seed weight, and days to flowering, and compare seed mineral concentrations between chickpeas and lentils grown in adjacent plots. Genotype effects, although significant in chickpea and lentil for all minerals except selenium, tended to be minimal compared to location, year, and their interaction effects. In both chickpeas and lentils high positive correlations were observed between seed concentrations of phosphorus and potassium, phosphorus and zinc, and potassium and zinc. Correlations between mineral concentration and yield, and mineral concentration and days to 50% flowering were similar for chickpeas and lentils across the majority of minerals. These results may reflect similarities between the two crops in physiological processes for mineral uptake and partitioning. Lentils had higher concentrations of iron and zinc than chickpea when the two crops were grown in adjacent plots,whereas chickpeas had higher concentrations of calcium and manganese. Plant genotypes that are more efficient at obtaining minerals from growing environments will be useful as parental materials to develop improved chickpea and lentil cultivars that have good yield potential coupled with high seed mineral concentrations.

关键词： Chickpea Lentil Mineral Nutrition Pulse

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Resistance risk assessment of six pyrethroids and acephate toward the resistant adult tarnished plant bug,Lygus lineolaris

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Insect Science 2024年第3期31卷 792-802页

作者： Yuzhe Du Shane Scheibener Yucheng Zhu Maribel Portilla Mingling Zhang usda-ars Southern Insect Management Research UnitStonevilleUSA usda-ars Pollinator Health in Southern Crop Ecosystem Research UnitStonevilleUSA

Due to rapidly developed resistance,pest management relies less on pyrethroids to control economically damaging infestations of the tarnished plant bug(TPB),Lygus lineolaris(Palisot de Beauvois)in cotton fields of ***,pyrethroid resistance remains prevalent in TPB *** study assessed the resistance levels in adult TPB to six common pyrethroids and *** TBPs were collected from wild host plants in late October after harvest in the Mississippi Delta region of the United *** on LCso values,the field-resistant TPBs displayed higher resistance to permethrin,esfenvalerate,and bifenthrin(approximately 30 fold)and moderate resistance toα-cyhalothrin,β-cyfluthrin,5-cypermethrin,and acephate(approximately 15 fold).Further investigations showed that the inhibitors of three detoxification enzyme,triphenyl phosphate(TPP),diethyl maleate(DEM),and piperonyl butoxide(PBO)had synergistic effects on permethrin,γ-cyhalothrin,and bifenthrin in resistant ***,elevated esterase,GST,and P450 activities were significantly expressed in fieldresistant ***,GST and esterase were reduced after 48 h exposure to certain pyrethroids at LCso *** synergistic and biochemical assays consistently indicated that P450 and esterase were involved in pyrethroid detoxification in *** study provides valuable information for the continued use of pyrethroids and acephate in controlling TPBs in cotton fields in the Mississippi Delta region of the United States.

关键词： cytochrome P450-monooxygenases(P450) detoxification enzyme activities esterase Lygus lineolaris pyrethroids and organophosphate resistance tarnished plant bug

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Applied and Environmental Chemistry of Animal Manure:A Review

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Pedosphere 2016年第6期26卷 779-816页

作者： Zhongqi HE Paulo H.PAGLIARI Heidi M.WALDRIP usda-ars Southern Regional Research Center Department of Soil Waterand ClimateUniversity of MinnesotaSouthwest Research and Outreach Center usda-ars Conservation and Production Research Laboratory

Animal manure consists of predominantly urine and feces, but also may contain bedding materials, dropped feed, scurf, and other farming wastes. Manure is typically applied to soils as fertilizer for agricultural production. The estimated amount of manure produced in 12 major livestock-producing countries is 9 × 10^9 Mg of manure annually. Manure is rich in plant nutrients. However, manure is also considered as an environmental pollutant when it is over-applied to cropland or following runoff into surface water. Manure can also influence global climate change via emissions of methane （CH4） and nitrous oxide （N2O）. Thus, increased and updated knowledge of applied and environmental chemistry of animal manure is needed to shed light on the research and development of animal manure utilization and minimization of its adverse environmental concerns. The advances in basic and applied studies of manure major components, organic matter, phosphorus, and nitrogen, primarily related to US livestock production are summarized in this review. Detailed focus was placed on three notable challenges for future manure research： 1） soil application of animal manure, 2） manure phytate phosphorus, and 3） manure nitrogen availability. This review may contribute to the global effort in sustainable and environmentally sound agriculture by stimulating new ideas and directions in animal manure research, and promoting application of knowledge and insight derived from manure research into improved manure management strategies.

关键词： environmental pollutant fertilizer nitrogen availability organic matter phosphorus phytate plant nutrients

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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

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Characterization of three transcripts encoding small heat shock proteins expressed in the codling moth, Cydia pomonella （Lepidoptera： Tortricidae）

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Insect Science 2011年第5期18卷 473-483页

作者： Stephen F. Garczynski Thomas R. Unruh Christelle Guedot Lisa G. Neven usda-ars Yakima Agricultural Research Laboratory Wapato Washington USA

Codling moth is a major pest of apples and pears worldwide. Increasing knowledge of how this insect responds to environmental stress will improve field and postharvest control measures used against it. The small heat shock proteins （sHsps） play a maj or role in cellular responses to environmental stressors. A degenerate oligonucleotide primer, designed against the conserved α-crystallin domain, was used in 3＇ rapid amplification of complementary DNA （cDNA） ends reactions to amplify transcripts encoding sHsps expressed in the codling moth cell line, Cp169, subjected to heat shock. Three full-length cDNAs were cloned from Cp169 cells that contained open reading frames encoding sHsps. The cDNA for CpHsp 19.8 was 795 bp encoding 177 amino acids. The cDNA for CpHsp 19.9 was 749 bp encoding 175 amino acids. The cDNA for CpHsp22.2 was 737 bp encoding 192 amino acids. Analysis of the protein sequences of the three CpHsps indicated the presence of 83 amino acids with homology to the α-crystallin domain. For each of the CpHsps, the α-crystallin domain was surrounded by divergent N- and C-terminal regions, consistent with the conserved structural features of sHsps. Real-time polymerase chain reaction, used to determine the expression patterns of each of the sHsps in different developmental stages of codling moth revealed the presence of transcripts in all stages tested. Consistent with characteristics of other sHsps, expression of CpHsp transcripts were greatly enhanced when insects were subjected to heat shock. The results of this research can be used as a guide to study the roles of sHsps in codling moth control using various post-harvest treatments.

关键词： α-crystallin domain heat shock response qPCR

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Transcriptome analysis of sugar beet root maggot （Tetanops myopaeformis） genes modulated by the Beta vulgaris host

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Insect Science 2018年第2期25卷 222-234页

作者： Haiyan Li Ann C. Smigocki usda-ars Molecular Plant Pathology Laboratory Beltsville Maryland US

Sugar beet root maggot （SBRM, Tetanops myopaeformis von R6der） is a major but poorly understood insect pest of sugar beet （Beta vulgaris L.）. The molecular mecha- nisms underlying plant defense responses are well documented, however, little information is available about complementary mechanisms for insect adaptive responses to overcome host resistance. To date, no studies have been published on SBRM gene expression pro- filing. Suppressive subtractive hybridization （SSH） generated more than 300 SBRM ESTs differentially expressed in the interaction of the pest with a moderately resistant （F1016） and a susceptible （F1010） sugar beet line. Blast2GO v. 3.2 search indicated that over 40% of the differentially expressed genes had known functions, primarily driven by fruit fly D. melanogaster genes. Expression patterns of 18 selected EST clones were confirmed by RT-PCR analysis. Gene Ontology （GO） analysis predicted a dominance of metabolic and catalytic genes involved in the interaction of SBRM with its host. SBRM genes function- ing during development, regulation, cellular process, signaling and under stress conditions were annotated. SBRM genes that were common or unique in response to resistant or susceptible interactions with the host were identified and their possible roles in insect responses to the host are discussed.

关键词： Beta vulgaris resistant sugar beet root maggot suppressive subtractivehybridization susceptible transcriptome

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Regulation of cytokine gene expression by orosomucoid in neonatal swine adipose tissue

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Journal of Animal Science and Biotechnology 2016年第3期7卷 403-411页

作者： Timothy G.Ramsay Margo J.Stoll Le Ann Blomberg Thomas J.Caperna Animal Biosciences and Biotechnology Laboratory USDA/ARSBeltsville Agricultural Research CenterUSDABeltsvilieMD 20705USA

Background： Porcine adipose tissue expresses orosomucoid（ORM1） mRNA, a protein with anti-inflammatory and immunomodulatory properties. Previous research has demonstrated that porcine ORM1 can reduce insulin stimulated glucose metabolism in porcine adipose tissue in vitro. The present study was designed to examine the preweaning ontogeny of ORM1 m RNA abundance in porcine subcutaneous adipose and to determine if ORM1 can regulate m RNA abundance of inflammatory cytokines that contribute to insulin resistance in primary cultures derived from neonatal porcine subcutaneous adipose tissue. Cultures were differentiated in vitro and subsequently the adipocyte containing cultures were incubated for 24 h with 0–5000 ng porcine ORM1/m L medium. Cultures were then harvested, total RNA extracted for use in reverse transcription and the m RNA abundance of cytokine m RNA quantified by real-time ***： ORM1 m RNA abundance within neonatal adipose tissue does not change from d 1 to d 21 of age and is a very small fraction relative to liver m RNA abundance. The ORM1 m RNA level in porcine adipocytes and stromalvascular cells are similar（P 〉 0.05）. Treatment with ORM1 did not affect TNFα（tumor necrosis factor α） m RNA level（P 〉 0.05）, while interleukin 6（IL6） m RNA abundance was reduced 32 % at 1,000 ng ORM1/m L（P 〈 0.01）. However,TNFα protein content in the cell culture media was reduced by ORM1 treatment（5,000 ng/m L, P 〈 0.05）, whereas ORM1 had no detectable effect on the media content of IL6（P 〉 0.05）. The reduction of macrophage migration inhibitory factor（MIF） m RNA abundance by ORM1 was dose dependent（P 〈 0.01）. Monocyte chemotactic protein（MCP） m RNA level was reduced 27 % by 1,000 ng ORM1/m L（P 〈 0.05）.Conclusions： The data suggest that ORM1 has limited effects TNFα, IL6, MIF or MCP expression at the concentrations tested. Secondly, these cytokines do not appear to contribute to the reported insulin resistance induced by ORM1 in porcine adipose tissue in vitro as an in

关键词： Adipose Cytokines Neonate Orosomucoid Swine

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Evaluation of maize inbred lines and topcross progeny for resistance to pre-harvest aflatoxin contamination

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The Crop Journal 2019年第1期7卷 118-125页

作者： Jake C.Fountain Hamed K.Abbas Brian T.Scully Hong Li Robert D.Lee Robert C.Kemerait Baozhu Guo usda-ars Crop Protection and Management Research Unit Department of Plant Pathology University of Georgia usda-ars Biological Control of Pests Research Unit usda-ars National Horticultural Research Laboratory Shanxi Academy of Agricultural Sciences Millet Research Institute Department of Crop and Soil Sciences University of Georgia

Pre-harvest aflatoxin contamination occurs in maize following kernel colonization by Aspergillus flavus. Aflatoxin contamination resistance is a highly desired trait in maize breeding *** identification of novel sources of resistance to pre-harvest aflatoxin contamination is a major focus in germplasm screening efforts. Here, we performed a field evaluation of 64 inbred lines over two years for pre-harvest aflatoxin contamination. Topcrosses were also performed with two testers, B73 and Mo17, to generate 128 F1 hybrids which were also evaluated over two years. Hybrid performance was used to calculate both general combining ability(GCA) of the inbreds, and observed heterosis for aflatoxin resistance. Over both years of the study, aflatoxin concentrations ranged from 80 ± 47 to 17,617 ± 8816 μg kg^(-1) for inbreds, and from 58 ± 39 to 2771 ± 780 μg kg^(-1) for hybrids with significant variation between years and lines. The inbred lines CML52, CML69, CML247, GT-603, GEMS-0005, Hi63, Hp301, and M37 W showed ars of the study and less than the resistant check, Mp313 E, in at least one season. Among these, CML52, GT-603, and Hi63 also showed significant GCA with the testers in hybrid progeny. CML52, GT-603, and M37 W also showed heterotic effects of-13.64%,-12.47%, and-24.50%, respectively, with B73 resulting in reduced aflatoxin contamination. GT-603 also showed a similar heterotic effect for aflatoxin contamination,-13.11%, with Mo17 indicating that this line may serve as a versatile source of aflatoxin contamination resistance in breeding programs.

关键词： Aspergillus flavus Pre-harvest Aflatoxin Maize Topcross

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