Previous View
APSnet Home
Phytopathology Home


Reaction of F2 Seedlings of Several Crosses of Susceptible and Resistant Wheat Selections to Puccinia striiformis. R. E. Allan, Geneticist, Crops Research Division, ARS, USDA, Pullman, Washington 99163; L. H. Purdy, Former Plant Pathologist, Crops Research Division, ARS, USDA, Pullman, Washington 99163, Present address: Department of Plant Pathology, University of Florida, Gainesville 32601. Phytopathology 60:1368-1372. Accepted for publication 7 April 1970. DOI: 10.1094/Phyto-60-1368.

We classified F2 progeny of crosses among nine sources of wheat (Triticum aestivum) with seedling resistance (Nord, Spaldings Prolific, Holzapfel Fruh, Rouge Prolifique Barbu, Heines Kolben, Ottawa/Renacimiento, Alba, P.I. 178383, and Suwon 92/3* Omar, 63301) and two seedling-susceptible selections (Omar and Gaines) for reaction to a culture of Puccinia striiformis. We also studied certain crosses among the nine seedling resistant sources. Pre- and postinoculation temp were 15 ± 2 C. In general, crosses of resistant parents with Omar produced higher proportions of plants in the resistant classes than crosses with Gaines. Resistant × susceptible crosses demonstrated monogenic control of reaction with P.I. 178383, Spaldings Prolific, and Sel.63301, whereas digenic control prevailed with Nord, Holzapfel Fruh, and Ottawa/Renacimiento. Eight resistant × resistant crosses indicated digenic control, but the crosses Nord/Spaldings Prolific, Nord//Ottawa/Renacimiento, P.I. 178383//Ottawa/Renacimiento, Nord/Rouge Prolifique Barbu, and P.I. 178383/Alba gave trigenic reaction patterns. No suitable interpretation could be made of the reaction pattern of the Sel.63301//Ottawa/Renacimiento cross. Evidence suggests that Nord, Heines Kolben, and P.I. 178383 have in common at least one gene that governs an intermediate reaction type.