Resistance of Maize Inbreds and their Hybrids to Fusarium Stalk Rot

Abstract

The resistance of 35 inbred lines and their 70 hybrids with two testers to stalk rot is described and the results of natural and artificial stalk infection are compared. A mixture of Fusarium spp. spores was used for artificial infections. The disease was scored for two years. Inbreds and hybrids differed significantly in resistance and infection types in both years. Generally, disease scores of hybrids were lower than of inbreds. No close association was found between lines and their testcross hybrids (r = -0.06 to 0.29) and between hybrids with the two testers (r = -0.04 to 0.38). The correlation coefficients of disease scores after natural and artificial infection were in inbreds and in hybrids highly significant (r = 0.45-0.87). The results suggest, that Fusarium stalk rot resistance should be tested in both inbreds and hybrids. We recommend for maize breeding, that tests with artificial infection should be followed by tests under natural infection.