Biology Commons^™

Heritability Of Latent Period Estimated From Wild-Type And Selected Populations Of Puccinia Triticina, Jeffrey Lehman

Biology and Earth Science Faculty Scholarship

Durability of partially resistant wheat cultivars to wheat leaf rust depends on the amount of genetic variation in parasitic fitness within populations of the pathogen Puccinia triticina. To assess the durability of partial resistance, selection experiments were used to explore quantitative variation in parasitic fitness of P. triticina. Fungal populations 881-WT and 882-WT were selected for shortened latent period on partially resistant cvs. CI 13277 and Sw 72469-6 for multiple generations. Fitness components were measured for wild-type and selected fungal populations. Responses to selection and selection differentials were calculated, and broad-sense, realized heritabilities for latent period were estimated for wild-type …

Relationship Among Genes Conferring Partial Resistance To Leaf Rust (Puccinia Triticina) In Wheat Lines Ci 13227 And L-574-1, Jeffrey Lehman

Biology and Earth Science Faculty Scholarship

This study describes the segregation of genes for resistance to the fungus Puccinia triticina in a cross between partially resistant wheat lines L-574-1 and CI 13227 with two and four genes for resistance, respectively. The objectives of this study were to use parental, F1, F2, and backcross populations to quantify maternal effects, degree of dominance, and transgressive segregation, and to determine whether CI 13227 and L-574- 1 share any resistance genes for long latent period or small uredinia. In two experiments conducted in the greenhouse, the uppermost leaf of adult wheat plants was inoculated prior to heading with P. triticina. …

Genetic Variation In Latent Period Among Isolates Of Puccinia Recondita F. Sp. Tritici On Partially Resistant Wheat Cultivars, Jeffrey Lehman

Biology and Earth Science Faculty Scholarship

The durability of partially resistant wheat cultivars to wheat leaf rust depends on the amount of genetic variation in parasitic fitness within populations of the pathogen Pucciniareconditaf. sp.tritici. To assess the durability ofpanialresistance, phenotypic variation inlatentperiod (a major component of parasitic fitness) was quantified and partitioned into genetic and nongenetic components for isolates of P.reconditaf. sp.triticion susceptible and partially resistant cultivars. Latent periods among isolates differed by 24 to 27% on individual partially resistant cultivars. In simulated epidemics, isolates with short latent periods caused 2 to 2.5 times more disease and overcame 13 to 35% of the

resistance of four …