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The evolution of Hessian fly from the Old World to the New World： Evidence from molecular markers

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Insect Science 2015年第6期22卷 768-784页

作者： Brandon J. Schemerhom Yan Ma Crane Charles f. Crane USDA-ARS Department of Entomology Department of Botany and Plant Pathology Purdue University West Lafayette IN 47907USA

Eighteen polymorphic microsatellite loci and 11 single-nucleotide polymor- phisms were genotyped in 1 095 individual Hessian fly specimens representing 23 popula- tions from North America, southern Europe, and southwest Asia. The genotypes were used to assess genetic diversity and interrelationship of Hessian fly populations. While phyloge- netic analysis indicates that the American populations most similar to Eurasian populations come from the east coast of the United States, genetic distance is least between （Alabama and California） and （Kazakhstan and Spain）. Allelic diversity and frequency vary across North America, but they are not correlated with distance from the historically documented point of introduction in New York City or with temperature or precipitation. Instead, the greatest allelic diversity mostly occurs in areas with Mediterranean climates. The mi- crosatellite data indicate a general deficiency for heterozygotes in Hessian fly. The North American population structure is consistent with multiple introductions, isolation by dis- tance, and human-abetted dispersal by bulk transport of puparia in infested straw or on harvesting equipment.

关键词： allele frequency Hessian fly microsatellite population structure SNP SSR

Integrating space and time: a case for phenological context in grazing studies and management

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frontiers of Agricultural Science and Engineering 2018年第1期5卷 44-56页

作者： Dawn M.BROWNING Sheri SPIEGAL Richard E.ESTELL Andres f.CIBILS Raul H.PEINETTI USDA-Agriculture Research Service New Mexico State University Department of Animal and Range Sciences New Mexico State University facultad de Agronomía Universidad Nacional de La Pampa

In water-limited landscapes, patterns in primary production are highly variable across space and *** grazing is a common agricultural practice worldwide and a concern is localized overuse of specific pasture resources that can exacerbate grass losses and soil erosion. On a research ranch in New Mexico with average annual rainfall of 217 mm, we demonstrate with a quantitative approach that annual seasons vary greatly and examine foraging patterns in Angus-Hereford(Bos taurus) cows. We define five seasonal stages based on MODIS NDVI: pre-greenup, greenup, peak green, drydown and dormant, and examine livestock movements in 2008. Daily distance traveled by cows was greater and foraging area expanded during periods with higher precipitation. A regression model including minimum NDVI, rainfall and their interaction explained 81% of the seasonal variation in distance traveled by cows(P foraging, but tended to explore smaller areas as the pasture became greener(greenup and peak green stages). Cows foraged an average of 9.7 h daily and spent more time foraging with more concentrated search patterns as pastures became *** findings suggest that phenological context can expand the capacity to compare and integrate findings, and facilitate meta-analyses of grazing studies conducted at different locations and times of year.

关键词： GPS collars Jornada Experimental Range land-surface phenology livestock movement LTAR MODIS NDVI rangeland

Ethanol Lock Therapy as additional treatment of catheter-related bloodstream infections in pediatric patients receiving home parenteral nutrition

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Open Journal of Pediatrics 2013年第4期3卷 397-402页

作者： Merel N. van Kassel Dasja Pajkrt Jim C. H. Wilde Cora f. Jonkers Merit M. Tabbers Department of Pediatric Infectious Diseases Emma’s Children’s Hospital Academic Medical Centre Amsterdam The Netherlands Department of Pediatric Surgery Emma’s Children’s Hospital Academic Medical Centre Amsterdam The Netherlands Home Parenteral Nutrition Team Emma’s Children’s Hospital Academic Medical Centre Amsterdam The Netherlands

Background: Catheter related bloodstream infections (cris) are a major cause of morbidity, mortality and prolonged hospitalization in pediatric patients with home parenteral nutrition (HPN). In recent years, new prophylactic and treatment options have been evaluated to reduce the incidence of cris and infection related catheter removals. In children, two retrospective studies have shown the efficacy of ethanol lock treatment (ELT) in reducing the incidence of cris in pediatric oncology patients. However, prospective data are missing. Our aim of the present study was to evaluate prospectively the effect of ELT on the cure and recurrence rate of cris, duration of hospitalization and antibiotic use in HPN pediatric patients. Methods: HPN children older than three months with a clinical suspicion of a CRI were included and randomised to ELT or standard flushing treatment (heparin or taurolidine). The primary outcomes were persistence and recurrence of the bacteraemia and Central Venous Access Device (CVAD) removal. Secondary outcomes included duration of antibiotic use, duration of hospitalization and side effects. Results: Data from eight HPN children experiencing 14 suspected CRI were analysed. Seven patients had proven cris by positive blood cultures. four were treated with ELT and three with their standard flushing treatment. One CRI persisted in the control group. In one single patient, bacteraemia recurred three times within 24 weeks. This patient had been enrolled in both study arms. A CVAD removal was needed in one patient because of occlusion. Conclusions: This small study showed no additional efficacy of the use of ELT on cure rate or recurrences of cris compared to standard therapy in HPN treated children. There were also no differences in duration of hospitalization, the use of antibiotics or CVAD removal between both groups.

关键词： Home Parenteral Nutrition Ethanol Lock Treatment Catheter Related Bloodstream Infections

Genomic location of Gb1, a unique gene conferring wheat resistance to greenbug biotype f

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The Crop Journal 2023年第5期11卷 1595-1599页

作者： Xiangyang Xu Genqiao Li Guihua Bai Brett fCarver Ruolin Bian Amy Bernardo JScott Armstrong USDA-ARS Wheat Peanutand Other Field Crop Research UnitStillwaterOK 74075USA USDA-ARS Hard Winter Wheat Genetics Research Unit ManhattanKS 66506USA Department of Agronomy Kansas State UniversityManhattanKS 66506USA Department of Plant and Soil Sciences Oklahoma State UniversityStillwaterOK 74078USA

Greenbug(Schizaphis graminum, Rondani) is a serious insect pest in many wheat growing regions and has been infesting cereal crops in the USA for over a century. Continuous occurrence of new greenbug biotypes makes it essential to explore all greenbug resistant sources available to manage this pest. Gb1, a recessive greenbug resistance gene in DS28A, confers resistance to several economically important greenbug biotypes and is the only gene found to be resistant to greenbug biotype f. A set of 174 f_(2:3)lines from the cross DS28A × Custer was evaluated for resistance to greenbug biotype f in 2020 and 2022. Selective genotyping of the corresponding f_(2) population using single nucleotide polymorphism(SNP) markers generated by genotyping-by-sequencing(GBS) led to the identification of a candidate genomic region for Gb1. Thus, SSR markers previously mapped in this region were used to genotype the entire f2population,and kompetitive allele specific PCR(KASP) markers were also developed from SNPs in the target ***1 was placed in the terminal region of the short arm of chromosome 1A, and its location was confirmed in a second population derived from the cross DS28A × PI 697274. The combined data analysis from the two mapping populations delimited Gb1 to a < 1 Mb interval between 13,328,200 and 14,241,426 bp on1AS.

关键词： Wheat Greenbug resistance gene Gb1 KASP markers Linkage analysis Genotyping-by-sequencing

Two haplotype-resolved genomes reveal important flower traits in bigleaf hydrangea(Hydrangea macrophylla)and insights into Asterid evolution

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Horticulture Research 2023年第12期10卷 45-57页

作者： Xingbo Wu Sheron A.Simpson Ramey C.Youngblood Xiaofen fLiu Brian E.Scheffler Timothy A.Rinehart Lisa W.Alexander Amanda M.Hulse-Kemp Department of Environmental Horticulture Tropical Research and Education CenterUniversity of FloridaHomesteadFL 33031United States Genomics and Bioinformatics Research Unit USDA-ARSRaleighNC 27695United States Genomics and Bioinformatics Research Unit USDA-ARSStonevilleMS 38776United States Institute for Genomics Biocomputing and BiotechnologyMississippi State UniversityStarkvilleMS 39762United States Crop Production and Protection USDA-ARSBeltsvilleMD 20705United States floral and Nursery Plants Research Unit U.S.National ArboretumUSDA-ARSMcMinnvilleTN 37110United States Department of Crop and Soil Sciences North Carolina State UniversityRaleighNC 27695United States

The Hydrangea genus belongs to the Hydrangeaceae family,in the Cornales order of flowering plants,which early diverged among the Asterids,and includes several species that are commonly used ornamental *** them,Hydrangea macrophylla is one of the most valuable species in the nursery trade,yet few genomic resources are available for this crop or closely related Asterid *** high-quality haplotype-resolved reference genomes of hydrangea cultivars‘Veitchii’and‘Endless Summer’[highest quality at 2.22 gigabase pairs(Gb),396 contigs,N5022.8 megabase pairs(Mb)]were assembled and scaffolded into the expected 18 *** the newly developed high-quality reference genomes along with high-quality genomes of other related flowering plants,nuclear data were found to support a single divergence point in the Asterids clade where both the Cornales and Ericales diverged from the *** mapping with an f1 hybrid population demonstrated the power of linkage mapping combined with the new genomic resources to identify the gene for inflorescence shape,CYP78A5 located on chromosome 4,and a novel gene,BAM3 located on chromosome 17,for causing double *** developed in this study will not only help to accelerate hydrangea genetic improvement but also contribute to understanding the largest group of flowering plants,the Asterids.

关键词： Hydra traits resolved