Inheritance of resistance to aspergillus ear rot and aflatoxin production of corn from CI2

This study determined the types and magnitude of gene action, estimated her itabilities, and predicted gain from selection for resistance to Aspergillu s ear rot and aflatoxin production in the cross of resistant corn inbred CI 2 to susceptible inbred B73 in 1998 and 1999. The warm, dry summer of 1998 favored aflatoxin production, whereas the conditions of 1999 did not. Resis tance to ear rot was mainly controlled by additive gene action. Aflatoxin v alues were analyzed by individual years (environments) because of the highl y significant generation x environment interaction. Resistance to aflatoxin production was mainly controlled by epistasis in 1998 and by additive gene action in 1999. Heritabilities for ear rot and aflatoxin production were h igher in the F-3 generation than in the BCP1-selfed generation. In 1998, Sp earman's correlation coefficients between Aspergillus ear rot ratings and a flatoxin values for the F-3 and the BCP1-selfed families were not significa nt (P > 0.05). In 1999, both were highly significant (P < 0.01), but low at 0.41 and 0.17 for the F-3 and BCP1-selfed generations, respectively. We fo und that CI2 is not an acceptable source of resistance due to lower heritab ilities and disease resistance compared to other sources of resistance.