NATURE AND INHERITANCE OF LEAF RUST RESISTANCE FROM THREE WHEAT CULTIVARS

Abstract

The nature and inheritance of leaf rust resistance of cultivars Manitou, Pavon 76 and Romany against Indian races 12, 77, 77-1, 77-3, 108 and 162 was studied. Manitou carried a dominant gene effective against race 162 that is different from Lr13 already reported from this cultivar. Pavon 76 and Romany carried the genes Lrl and LrlO as well as a new dominant gene for low seedling reaction against race 108. In addition, Romany also carried a gene for low seedling reaction against race 77-1 and a new adult plant resistance gene against race 77-3. The field resistance of cultivars Manitou and Pavon 76 against race 77-1, without evident hypersensitive response was conditioned by duplicate genes and it is proposed to be durable. The resistance of Romany in field tests against race 77-1 was also due to duplicate genes but at least one of these genes is hypersensitive in nature.