Characterization of sugarcane cultivars response to orange rust in greenhouse

Abstract

Sugarcane orange rust, caused by Puccinia kuehnii (Krüguer) Butler, is considered one of the most important diseases, due to losses in agricultural yields in susceptible commercial plantations. The objective of this work was to characterize the response of sugarcane cultivars to orange rust in green house conditions. Sugarcane plants of two months old were inoculated with spore suspension obtained from pustules on sugarcane leaves (‘C01-227’) with orange rust symptoms. Previously to inoculum preparation, P. kuehnii occurrence were confirmed by optical microscopy and polymerase chain reaction techniques. The experimental conditions used allow identify differential response between sugarcane cultivars to P. kuehnii infection. Some cultivars showed to be resistant to the fungus through interactions incompatible with a typical hypersensitive response. In other cultivars, different grades of susceptibility with significant differences in latency period of the disease was observed. Key words: Puccinia kuehnii, resistance, Saccharum spp.