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James R Hanson - One of the best experts on this subject based on the ideXlab platform.

Jacqueline A Takahashi - One of the best experts on this subject based on the ideXlab platform.

Christopher C. Mundt - One of the best experts on this subject based on the ideXlab platform.

  • Resistance Screening and Pathogenic Variability
    2016
    Co-Authors: Christopher C. Mundt
    Abstract:

    caused by the soilborne fungus Cephalosporium gramineum, results in significant yield reductions in dryland winter wheat crops of the U.S. Pacific Northwest. The development of resistant cultivars offers the best hope for disease control. Breeding for resistance is hampered by the long trial times inherent in screening adult plants, and by cultivar x environment interactions in field tests. The principal objective of this research was to develop and test a procedure for screening wheat seedlings in controlled environments for resistance t

  • identification of Cephalosporium stripe resistance quantitative trait loci in two recombinant inbred line populations of winter wheat
    Theoretical and Applied Genetics, 2015
    Co-Authors: Dolores M Vazquez, Robert S Zemetra, James C Peterson, Christopher C. Mundt
    Abstract:

    Identification of genome regions linked to Cephalosporium stripe resistance across two populations on chromosome 3BS, 4BS, 5AL, C5BL. Results were compared to a similar previous study. Cephalosporium stripe is a vascular wilt disease of winter wheat (Triticum aestivum L.) caused by the soil-borne fungus Cephalosporium gramineum Nisikado & Ikata. In the USA it is known to be a recurring disease when susceptible cultivars are grown in the wheat-growing region of Midwest and Pacific Northwest. There is no complete resistance in commercial wheat cultivars, although the use of moderately resistant cultivars reduces the disease severity and the amount of inoculum in subsequent seasons. The goal of this study was to detect and to compare chromosomal regions for resistance to Cephalosporium stripe in two winter wheat populations. Field inoculation was performed and Cephalosporium stripe severity was visually scored as percent of prematurely ripening heads (whiteheads) per plot. ‘Tubbs’/‘NSA-98-0995’ and ‘Einstein’/‘Tubbs’, each comprising a cross of a resistant and a susceptible cultivar, with population sizes of 271 and 259 F (5:6) recombinant inbred lines, respectively, were genotyped and phenotyped across four environments. In the quantitative trait loci (QTL) analysis, six and nine QTL were found, explaining in total, around 30 and 50 % of the phenotypic variation in ‘Tubbs’/‘NSA-98-0995’ and ‘Einstein’/‘Tubbs’, respectively. The QTL with the largest effect from both ‘NSA-98-0995’ and ‘Einstein’ was on chromosome 5AL.1 and linked to marker gwm291. Several QTL with smaller effects were identified in both populations on chromosomes 5AL, 6BS, and 3BS, along with other QTL identified in just one population. These results indicate that resistance to Cephalosporium stripe in both mapping populations was of a quantitative nature.

  • biology and control of Cephalosporium stripe of wheat
    Plant Pathology, 2014
    Co-Authors: Martin Quincke, T D Murray, C J Peterson, K E Sackett, Christopher C. Mundt
    Abstract:

    Cephalosporium stripe, caused by the fungus Cephalosporium gramineum, is the only known vascular wilt disease of small grain cereals. The pathogen causes characteristic striping of leaf blades and sheaths, but can also result in seedling death, stunting, and sterile seed heads (white heads). Cephalosporium stripe is a disease of autumn (fall)-sown wheat, especially in cool and wet production regions. The disease is further favoured by early sowing, reduced tillage practices, low pH soils, and by frost heaving that damages roots. Infections occur almost entirely from spores produced on surface crop debris that are washed into the soil, although a low level of seed transmission can also occur. The pathogen colonizes root epidermis and cortical cells, subsequently moves into the vascular tissue, and eventually spreads throughout the entire plant. Production of fungal toxin(s) and extracellular polysaccharides probably play an important role in pathogenesis. Cultural practices such as delayed sowing, crop rotation, destruction of crop debris, liming of soil and fertilizer management all have potential to reduce the incidence of Cephalosporium stripe. All of these cultural practices have negative economic impacts and/or increase soil erosion, and thus there is much interest in the development of resistant cultivars. There is potential for introgression of highly effective resistance from wild species into cultivated wheat. Genes for quantitatively inherited resistance can also be accumulated within cultivated wheat to attain moderate resistance. The continued use of cultivars with moderate resistance will probably be sufficient for long-term control of the disease.

  • relationship between incidence of Cephalosporium stripe and yield loss in winter wheat
    International Journal of Agronomy, 2012
    Co-Authors: Martin Quincke, C J Peterson, Christopher C. Mundt
    Abstract:

    Cephalosporium stripe (caused by Cephalosporium gramineum) can be a serious disease of winter wheat (Triticum aestivum L.) in the Pacific Northwest of the USA. Effects of Cephalosporium stripe on yield, test weight, protein, and kernel characteristics were examined using 12 winter wheat varieties in field plots inoculated and not inoculated with the pathogen. Averaged over varieties, inoculation decreased yield, test weight, kernel weight, and kernel diameter; grain protein and the standard deviations of kernel weight and kernel diameter were increased by inoculation. Grain yield of the susceptible check was reduced by as much as 41% with addition of inoculum. The most resistant and the most susceptible varieties performed similarly for yield in the two environments, while varieties with intermediate levels of resistance were sometimes inconsistent. There was a linear relationship between yield and % whiteheads (sterile heads caused by disease) in one environment and a curvilinear relation in the other.

  • quantitative trait loci analysis for resistance to Cephalosporium stripe a vascular wilt disease of wheat
    Theoretical and Applied Genetics, 2011
    Co-Authors: Martin Quincke, James C Peterson, Robert S Zemetra, Jennifer L Hansen, Jianli Chen, Oscar Rieralizarazu, Christopher C. Mundt
    Abstract:

    Cephalosporium stripe, caused by Cephalosporium gramineum, can cause severe loss of wheat (Triticum aestivum L.) yield and grain quality and can be an important factor limiting adoption of conservation tillage practices. Selecting for resistance to Cephalosporium stripe is problematic; however, as optimum conditions for disease do not occur annually under natural conditions, inoculum levels can be spatially heterogeneous, and little is known about the inheritance of resistance. A population of 268 recombinant inbred lines (RILs) derived from a cross between two wheat cultivars was characterized using field screening and molecular markers to investigate the inheritance of resistance to Cephalosporium stripe. Whiteheads (sterile heads caused by pathogen infection) were measured on each RIL in three field environments under artificially inoculated conditions. A linkage map for this population was created based on 204 SSR and DArT markers. A total of 36 linkage groups were resolved, representing portions of all chromosomes except for chromosome 1D, which lacked a sufficient number of polymorphic markers. Quantitative trait locus (QTL) analysis identified seven regions associated with resistance to Cephalosporium stripe, with approximately equal additive effects. Four QTL derived from the more susceptible parent (Brundage) and three came from the more resistant parent (Coda), but the cumulative, additive effect of QTL from Coda was greater than that of Brundage. Additivity of QTL effects was confirmed through regression analysis and demonstrates the advantage of accumulating multiple QTL alleles to achieve high levels of resistance.

Qipeng Yuan - One of the best experts on this subject based on the ideXlab platform.

T D Murray - One of the best experts on this subject based on the ideXlab platform.

  • biology and control of Cephalosporium stripe of wheat
    Plant Pathology, 2014
    Co-Authors: Martin Quincke, T D Murray, C J Peterson, K E Sackett, Christopher C. Mundt
    Abstract:

    Cephalosporium stripe, caused by the fungus Cephalosporium gramineum, is the only known vascular wilt disease of small grain cereals. The pathogen causes characteristic striping of leaf blades and sheaths, but can also result in seedling death, stunting, and sterile seed heads (white heads). Cephalosporium stripe is a disease of autumn (fall)-sown wheat, especially in cool and wet production regions. The disease is further favoured by early sowing, reduced tillage practices, low pH soils, and by frost heaving that damages roots. Infections occur almost entirely from spores produced on surface crop debris that are washed into the soil, although a low level of seed transmission can also occur. The pathogen colonizes root epidermis and cortical cells, subsequently moves into the vascular tissue, and eventually spreads throughout the entire plant. Production of fungal toxin(s) and extracellular polysaccharides probably play an important role in pathogenesis. Cultural practices such as delayed sowing, crop rotation, destruction of crop debris, liming of soil and fertilizer management all have potential to reduce the incidence of Cephalosporium stripe. All of these cultural practices have negative economic impacts and/or increase soil erosion, and thus there is much interest in the development of resistant cultivars. There is potential for introgression of highly effective resistance from wild species into cultivated wheat. Genes for quantitatively inherited resistance can also be accumulated within cultivated wheat to attain moderate resistance. The continued use of cultivars with moderate resistance will probably be sufficient for long-term control of the disease.

  • pcr based detection of Cephalosporium gramineum in winter wheat
    Plant Disease, 2012
    Co-Authors: K L E Klos, L M Vasquezsiller, Calzada Antonio Narro, H C Wetzel, T D Murray
    Abstract:

    Klos, K. L. E., Vasquez-Siller, L. M., Wetzel, H. C., III, and Murray, T. D. 2012. PCR-based detection of Cephalosporium gramineum in winter wheat. Plant Dis. 96:437-442. A polymerase chain reaction (PCR) assay was developed amplifying a 496-bp fragment of the internal transcribed spacer region of Cephalosporium gramineum genomic DNA at concentrations of 100 fg/µl. Winter wheat seed and seedlings were collected from field plots where C. gramineum was present. Seed was tested by PCR using 20-seed samples bulked for DNA extraction. Estimates of seed infection, based on isolation of the pathogen on semiselective medium and PCR, were comparable at 0.18 and 0.13% of winter wheat ‘Stephens’ (P = 0.6042), and 0.45 and 0.58% of experimental line WA7970 (P = 0.5636), respectively. PCR differentiated between plants with welldeveloped symptoms of Cephalosporium stripe and noninoculated plants. Positive PCR was obtained from 22% of asymptomatic leaf blades from inoculated plants. We found no false positives when PCR and C. gramineum isolation on a semiselective medium were performed using tissue from the same leaf. The PCR assay has potential to diagnose Cephalosporium stripe disease prior to the appearance of symptoms. Negative PCR for some samples from which C. gramineum was isolated suggests that C. gramineum may be present below the level of detection in some asymptomatic leaves. This PCR assay may be useful for investigations into C. gramineum infection of wheat. The soilborne fungus Cephalosporium gramineum Y. Nisik. & Ikata causes Cephalosporium stripe, a vascular wilt disease of wheat and other grasses. C. gramineum is a widespread pathogen in the United States and other wheat-producing countries where winter wheat is subjected to snow cover and frozen soil. Cephalosporium stripe has been reported is several U.S. states where it occurs sporadically; however, it is a widespread, chronic disease in the wheat-growing region of eastern Washington State (6,7,12). Infection of winter wheat (Triticum aestivum L.) by C. gramineum is thought to occur mainly during winter and early spring via root injury due to freeze stress and frost heaving (4,25). Crown roots appear to be the primary infection site, and the pathogen colonizes adjacent stems through the crown tissues (14,26). C. gramineum also penetrates and colonizes stems through the leaf sheath epidermis or wounds where tillers emerge (8).

  • seed transmission of Cephalosporium gramineum in winter wheat
    Plant Disease, 2006
    Co-Authors: T D Murray
    Abstract:

    Although isolation of Cephalosporium gramineum from wheat (Triticum aestivum) seed has been reported, development of Cephalosporium stripe in plants from infected seed has not been demonstrated experimentally. Winter wheat seed was collected from three experimental field plots where Cephalosporium stripe was present, and C. gramineum was isolated from the seed following surface-disinfection and incubation on a semi-selective medium. C. gramineum was isolated from 0.10 to 0.88% of seed from 11 of 12 cultivars in a field experiment at Pullman, WA, and from 0.10 to 0.30% of seed from 3 of 4 genotypes in a field experiment at Fort Hall, ID; differences among cultivars were not significant in either experiment. C. gramineum was isolated from 0.35 and 0.55% of cv. Stephens plants with no symptoms and severe symptoms, respectively, from a uniform seeding in Pullman. Seed of the four genotypes from Fort Hall and Stephens from Pullman were grown under controlled environment in a soilless potting mix with no added inoculum and in which C. gramineum was not detected. Symptoms of Cephalosporium stripe developed in 0.08 and 0.17% of Stephens and breeding line 87-00314A plants, respectively, from Fort Hall, and from 0.18 and 0.55% of Stephens plants with no symptoms and severe symptoms, respectively. Although development of Cephalosporium stripe in plants grown from seed lots harvested from diseased plants was low, infected seed can provide an important source of inoculum for introducing the pathogen and initiating epidemics in areas where the pathogen did not occur previously.

  • perennial wheat germ plasm lines resistant to eyespot Cephalosporium stripe and wheat streak mosaic
    Plant Disease, 2002
    Co-Authors: C M Cox, T D Murray, S S Jones
    Abstract:

    Cox, C. M., Murray, T. D., and Jones S. S. 2002. Perennial wheat germ plasm lines resistant to eyespot, Cephalosporium stripe, and wheat streak mosaic. Plant Dis. 86:1043-1048. A perennial wheat cropping system on the Palouse Prairie of eastern Washington may provide an alternative to the Federal Conservation Reserve Program and reduce soil erosion while providing a harvestable crop for growers. Twenty-four perennial wheat germ plasm lines resulting from crosses between wheat and wheatgrass were evaluated under controlled environment conditions for resistance to Wheat streak mosaic virus (WSMV), Cephalosporium gramineum, and Tapesia yallundae (anamorph Pseudocercosporella herpotrichoides var. herpotrichoides). Perennial wheat lines SS452, SS103, SS237, MT-2, and PI 550713 were resistant to all three pathogens. Eight lines (33%) were resistant to WSMV at 21°C and 25°C; AT3425 was resistant to WSMV at 21°C but not at 25°C. Thirteen lines (54%) were highly to moderately resistant to C. gramineum. Thirteen lines (54%) were resistant to T. yallundae in each experiment, but the reactions of four lines differed between experiments. The wheatgrasses Thinopyrum intermedium (PI 264770) and Thinopyrum ponticum (PI 206624) are reported as new sources of resistance to T. yallundae. Perennial wheat must have resistance to these diseases in order to be feasible as a crop in the Pacific Northwest.

  • characterization of an agropyron elongatum chromosome conferring resistance to Cephalosporium stripe in common wheat
    Genome, 1996
    Co-Authors: Xiwen Cai, Stephen S Jones, T D Murray
    Abstract:

    Related wheat (Triticum aestivum L.) breeding lines, PI 561033, REA 9232, REA 9257, and CI 13113 were analyzed cytogenetically to characterize the association of resistance to Cephalosporium stripe...