INHERITANCE OF LOOSE SMUT RESISTANCE: II. INHERITANCE OF RESISTANCE IN THREE BARLEY VARIETIES TO RACES 1, 2, AND 3 OF USTILAGO NUDA (JENS.) ROSTR.

Abstract

The inheritance of resistance of the barley varieties Br. 5479–754, a derivative of Jet (C.I. 967), PR28, a derivative of C.I. 4966, and Valkie (C.I. 5748) to races 1, 2 and 3 of Ustilago nuda (Jens.) Rostr. was studied. The genes for resistance in all varieties were dominant in effect. Resistance to races 2 and 3 in Br. 5479–754 was due to a single gene and resistance to race 1 to duplicate genes. A single gene in PR28 controlled resistance to all three races. Valkie proved susceptible to race 2 and had single and independent genes for resistance to each of races 1 and 3. The genes for resistance to the various smut races in each variety was independent of those in the other two.The winter barley variety C.I. 4966 is a valuable new source of immunity to U. nuda.