A study of patient attitudes toward optometric care at the Forest Grove clinic

A study of patient attitudes toward optometric care at the Forest Grove clini

Discovery of Heterodera filipjevi in Washington and comparative virulence with H. avenae on wheat

The cereal cyst nematode Heterodera avenae suppresses wheat production in the western United States. A second species of cereal cyst nematode, H. filipjevi, was identified in eastern Oregon during 2008. This paper reports the discovery of H. filipjevi–infested fields in eastern Washington, thereby extending the known distribution of H. filipjevi in the United States. The identity of H. filipjevi was determined and confirmed by species-specific polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism (RFLP), sequencing, and cyst morphology. Soils that were collected from naturally infested fields in Washington were used to compare the virulence of H. avenae and H. filipjevi on six spring wheat cultivars under controlled-environment conditions. Noninfested soils from nearby fields were used as controls. Cultivars Ouyen and WB Rockland were resistant to H. avenae and susceptible to H. filipjevi. Cultivars Sönmez and SY Steelhead were resistant to H. filipjevi and susceptible to H. avenae. Cultivars Louise and WB 936 were susceptible to both species. The resistance of SY Steelhead to ‘H. avenae’, reported in a previous paper, is corrected as resistance to H. filipjevi due to an earlier misidentification of H. filipjevi. Management guidelines that include crop rotations and resistant cultivars are presented. Discovery of additional infestations of H. filipjevi are anticipated when DNA-based tests become used routinely in commercial diagnostic laboratories

Cereal cyst nematodes : biology and management in Pacific Northwest wheat, barley, and oat crops

Cereal cyst nematodes reduce yields of wheat, barley, and oats in the Pacific Northwest states of Idaho, Oregon, and Washington. It is estimated that these pests reduce wheat profitability in these states by at least $3.4 million annually. This publication describes the distribution, biology, damage, management, and detection of cereal cyst nematodes.Published October 2010. A more recent revision exists. Please check for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogKeywords: Pacific Northwest, Heterodera filipjevi, cereal crops, Heterodera avenae, cereal cyst nematode

Spring Barley Resistance and Tolerance to the Cereal Cyst Nematode Heterodera avenae

Heterodera avenae is a cereal cyst nematode that reduces wheat yields in the Pacific Northwest USA. Barley is also susceptible but there were no previous reports of resistance or tolerance to H. avenae in the USA. Spring barley cultivars were assayed in H. avenae-infested fields over two years. Cultivars were planted in plots treated or not treated with aldicarb. Forty-five cultivars were evaluated for the market classes of 2- and 6-row feed barleys and 2- and 6-row malt barleys. One 2-row feed barley (Lenetah) was ranked as resistant and four were tolerant or very tolerant. One 2- row malt barley (Odyssey) was very resistant and 10 were tolerant or very tolerant. Two 6-row feed and two 6-row malt barleys were tolerant or very tolerant but none were resistant. Seven feed barleys were ranked as having a balance of at least moderate resistance plus moderate tolerance; Champion, Lenetah, Xena, Idagold II, Transit, Millenium and Goldeneye. This is the first report of resistance and tolerance of barley in H. avenae-infested fields in the Pacific Northwest. Barley productivity can be improved by planting resistant plus tolerant cultivars or by using highly resistant and highly tolerant cultivars as parents in barley improvement programs

Detection of Dual Heterodera avenae Resistance plus Tolerance Traits in Spring Wheat

The cereal cyst nematode Heterodera avenae reduces wheat yield in the Pacific Northwest. Resistance and tolerance traits among spring wheat cultivars were poorly defined. Screening trials were conducted with 39 cultivars over a 2-yr period in irrigated commercial fields that were infested by H. avenae. Comparisons were made between drill strips treated or untreated with aldicarb at the time of planting. Root sampling at the time of plant anthesis indicated that cultivars differed greatly in susceptibility to H. avenae, with numbers of newly produced white H. avenae females ranging from <5 to 70/plant. Aldicarb reduced mean numbers of white females as much as 99% on the most susceptible cultivar (Glee) and increased mean grain yield as much as 77% for the least tolerant cultivar (Cataldo). Density of H. avenae eggs in untreated soil following harvest was significantly lower than the density in aldicarb-treated plots. Agronomically acceptable traits of resistance plus tolerance were identified in one cultivar of hard red spring wheat (WB-Rockland) and two cultivars of hard white spring wheat (Klasic and LCS Star) but in none of the soft white spring wheat cultivars. This is the first report of spring wheat cultivars expressing the dual traits of resistance plus tolerance to H. avenae.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The American Phytopathological Society and can be found at: https://doi.org/10.1094/PDIS-09-15-1055-R

Detection and Quantification of Pratylenchus thornei in DNA Extracted from Soil Using Real-Time PCR

The root-lesion nematode Pratylenchus (hornet is one of the most important pests restricting productivity of wheat in the Pacific Northwest (PNW). It is laborious and difficult to use microscopy to count and identify the nematodes in soils. A SYBR Green I-based real-time polymerase chain reaction (PCR) assay was developed to detect and quantify this species from DNA extracts of soil. A primer set, designed from the internal transcribed spacer region (ITSI) of rDNA, was highly specific to P. thornei and did not amplify DNA from 27 isolates of other Pratylenchus spp., other nematodes, and six fungal species present in PNW wheat fields. A standard curve relating threshold cycle and log values of nematode number was generated from artificially infested soils. The standard curve was supported by a high correlation between the numbers of P thornei added to soil and the numbers quantified using real-time PCR. Examination of 15 PNW dryland field soils and 20 greenhouse samples revealed significant positive correlations between the numbers determined by real-time PCR and by the Whitehead tray and microscopic method. Real-time PCR is a rapid, sensitive alternative to time-consuming nematode extractions, microscopic identification, and counting of P thornei from field and greenhouse soils.Keywords: root disease, Pacific Northwest, Potato cyst nematode, Root lesion nematodes, Quantitative PCR, Meloidogyne incognita, in silico analysis, Genus pratylenchus, Polymerase chain reaction, Fragment length polymorphism, Wheat, IdentificationKeywords: root disease, Pacific Northwest, Potato cyst nematode, Root lesion nematodes, Quantitative PCR, Meloidogyne incognita, in silico analysis, Genus pratylenchus, Polymerase chain reaction, Fragment length polymorphism, Wheat, Identificatio

Controlling root and crown diseases of small grain cereals [2012]

Published November 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogThis publication describes practices to manage and minimize losses from root and crown diseases of wheat and barley throughout the Pacific Northwest.Keywords: green bridge effect, wheat, seed treatment, small grain cereals, crown disease, barley, root disease, crop rotation, cereal crops, pathoge

Identification of Resistance to Pratylenchus neglectus and Pratylenchus thornei in Iranian Landrace Accessions of Wheat

The pathogenic nematodes Pratylenchus neglectus (Rensch, 1924) Filipjev and Schuurmans Stekhoven, 1941 and Pratylenchus thornei Sher and Allen, 1953 cause severe yield losses in wheat (Triticum aestivum L.). The objectives in this study were to assay a collection of Iranian landrace accessions collected from 12 provinces in Iran to identify novel sources of resistance to both species and to characterize agronomic traits critical for consideration in wheat breeding. Seventy-eight accessions were assayed for dual resistance to parasitic nematodes P. neglectus and P. thornei in controlled environment assays. Field trials conducted in Pullman, WA, and Pendleton, OR, evaluated stripe rust (Puccinia striiformis f. sp. tritici) resistance, days to heading, grain volume weight, plant height, seed protein content, seed kernel characterization, glume tenacity, and pubescence. The accessions were assayed with simple-sequence repeat (SSR), single-nucleotide polymorphism (SNP), and known vernalization markers for hierarchical cluster analysis to identify relatedness among accessions. Thirty-two accessions were identified as resistant or moderately resistant to both Pratylenchus species. Six were identified with moderate adult plant resistance to stripe rust in the field. The range of mean agronomic traits over locations was 53 to 105 cm for plant height, 46 to 84 d for post planting days to heading, and 151 to 728 kg m⁻³ for grain volume weight. The genetic cluster analysis identified three clusters based on the number of rare polymorphisms in the subset. The nematode resistance was distributed over the three clusters. The diversity within this subset could be useful for wheat breeders to integrate genetic variation and resistance to both Pratylenchus spp