Varietal Reaction Arietal Reaction and Inheritance Trends of Susceptibility of Sugarcane to Rust (Puccinia melanocephala H. and P. SVD)

Abstract

A total of 452 sugarcane clones were tested for their reaction to rust by field evaluation. These included introduced, locally-developed commercial and breeding varieties, the original clones of Saccharum species, and the S. spontaneum hybrids of F₁, BC₁, and BC₂ generations. The inheritance trends of susceptibility to rust were also studied. It was found that nearly 54% of the clones tested were infected by the rust, and 15% were either susceptible or highly susceptible. In the genus Saccharum, most of S. officinarum clones were infected with the rust although the infection in most cases was mild. A clear inheritance trend of rust susceptibility was established from percent infection values of the original seedlings. These values were obtained from crosses with parental varieties having known reactions to the disease. In addition to variety, other factors affecting the incidence of the disease are discussed.