Expression of Wheat Leaf Rust Resistance Gene<i>Lr34</i>in Seedlings and Adult Plants

Abstract

The expression of wheat leaf rust resistance genes Lr34, LrT3, and Lr12 was studied in seedlings of cv. Thatcher and the near-isogenic Thatcher genotypes RL6058-Lr34, line 920-Lr34, line 922-LrT3, and RL6011-Lr12 inoculated at 8 and 13 days old. Several Mexican pathotypes of Puccinia recondita f. sp. tritici were used for inoculation. Incubation was carried out at four temperature regimes (three greenhouse and one growth chamber). Gene Lr34 conferred resistance to all pathotypes, although the seedling infection types (ITs) varied among tests and ranged from slightly chlorotic flecks to 3+ (.)