VIEW ARTICLE

Genetics

Inheritance of Virulence and Uredial Color and Size in Puccinia recondita tritici. G. D. Statler, Professor, Department of Plant Pathology, North Dakota State University, Fargo 58105; D. A. Jones, technician, Department of Plant Pathology, North Dakota State University, Fargo 58105. Phytopathology 71:652-655. Accepted for publication 22 November 1980. Copyright 1981 The American Phytopathological Society. DOI: 10.1094/Phyto-71-652.

Virulence, uredial length, width, area, and color, and chlorosis on wheat were recorded for each of 70 F₂ Puccinia recondita tritici cultures from a cross between cultures 70-197 and 71-112. These variables were compared to the F₁ and parents. P. recondita uredial size was normally distributed and did not fit discrete classes. Uredial length appeared to be under genetic control. Significant correlations were found between virulence and length, and virulence and area, on wheat with genotype LrEG and between virulence and pustule width, and virulence and color on wheat with Lr23. No other significant correlations existed for the variables studied. Chi-square tests did not indicate linkage between virulence, color, uredia size, or chlorosis. Uredia color was apparently controlled by a single dominant gene that was independent of genes for virulence. Single recessive genes conditioned virulence on genotypes Lr1, Lr3, Lr11, Lr17, LrEG, and experimental line 5534. The single recessive genes for virulence were inherited independently except for p³ and pEG and for p¹⁷ and pEG for which the chi-square tests indicated linkage. The possibility of intermediate infection types caused by cultures in the heterozygous condition is discussed.