Inheritance of virulence in Puccinia recondita on six backcross lines of wheat with single genes for resistance to leaf rust

Abstract

The inheritance of virulence on six backcross lines with genes for resistance to leaf rust (P. recondita Rob. ex Desm.) was investigated using cultures obtained from selfing race 11 and, in some cases, F1 cultures of race 9 × race 11 and race 11 × race 161 and F1 and F2 cultures of race 9 × race 161. Race 11 was heterozygous for recessive genes for virulence on Thatcher*6/Kenya W1483 (Lr15), Lee FL310/6*Thatcher (Lr23), Thatcher*6/Terenzio, Thatcher*6/El Gaucho and for a dominant gene on Thatcher*6/Carina (LrB) and homozygous virulent on Thatcher*6/Exchange. On the basis of the F1 hybrid cultures, race 9 was homozygous for virulence on Lr15 and Thatcher*6/Exchange and homozygous for a virulence on Lr23 and LrB; while race 161 was homozygous for virulence on Lr15 and heterozygous for virulence on Lr23, Thatcher*6/Exchange, and possibly LrB.The rust cultures used in the present study were used in previous virulence inheritance studies on host genes Lr1, Lr2, Lr3, Lr3ka, Lr14a, Lr14b, and Lr17. Virulence on Lr3ka was linked with virulence on Thatcher*6/Terenzio (3.7 ± 1.93%) and virulence on Lr3 with virulence on Lr14a (3.9 ± 1.62%); all others were independent.