INHERITANCE OF THATCHER-TYPE RESISTANCE TO COMMON ROOT ROT IN SPRING WHEAT

Abstract
Inheritance of reaction to common root rot, caused chiefly by Cochliobolus sativus, was studied in F3 populations of wheat, Triticum aestivum, from crosses between the root-rot-resistant, hollow-stemmed varieties, Thatcher and Pembina, and the moderately root-rot-susceptible, solid-stemmed variety, CT 733. The results indicated that the resistance of Thatcher and Pembina, which appear to have the same gene complement, is controlled by a major recessive gene and one or two minor genes.No association was found between inheritance of root-rot reaction and the inheritance of stem solidness which determines resistance to the wheat stem sawfly (Cephus cinctus). Therefore, there should be no difficulty in incorporating root-rot resistance into sawfly-resistant varieties.