Resistance to Magnaporthe Grisea Among Brazilian Wheat Genotypes

Abstract

Magnaporthe grisea, the causal organism of wheat head blast may induce important yield losses in wheat and barley crops in Brazil. Chemical control besides been expensive is not effective on highly susceptible varieties. Thus, the use of wheat genotypes with reasonable level of resistance associated with fungicides appears as the most effective means of control of the disease. The research carried out has the objective of evaluating the resistance of Brazilian wheat genotypes to wheat blast under controlled environment conditions. A great variability in reaction to head blast of wheat was observed among Brazilian varieties and advanced breeding lines tested. The range of head infection varied from 10 % to 86 % in average, but none among hundred varieties tested displayed high level of resistance to M. grisea. Nevertheless, some varieties and advanced breeding lines showed moderate resistance and eighteen of them displayed average infections lower than the control BR 18, a known moderately resistant variety under field condition