Virulence of Helminthosporium tetramera for root rot and foliar blight on wheat and rice crops and characterization by RAPD-PCR

摘要

Helminthosporium tetramera [Cochliobolus spicifer] isolates were isolated and identified from the roots of wheat and rice crops, and their aggressiveness was studied using aggressiveness analysis in the greenhouse. Isolates of H. tetramera were genetically characterized using Random Amplified Polymorphism DNA (RAPD). The investigations were based on two surveys of wheat and one survey of rice. In root aggressiveness analysis, the overall number of aggressive isolates was higher on wheat compared to rice. In the foliar aggressiveness test, the number of non-aggressive isolates was almost the same on wheat and rice varieties. RAPD was used to study the polymorphism and genetic variation within the population of H. tetramera that established to study correlation between taxonomical, aggressiveness and genetical characters. The H. tetramera tree is constructed based on the pattern of bands. This study highlighted the correlation between morphological, aggressiveness and genetic variations of H. tetramera.