Proposal and reclassification of standards for resistance studies of brown rust sugarcane

Abstract

In Cuba, the methodology used for sugarcane brown rust resistance evaluation has limited patterning, which makes it difficult to adequately handle cultivars in the intermediate categories of reaction, provided that from an agro-productive point of view they are interest. Six known reaction patterns and 11 commercial cultivars were studied. The variables, length, amount and percentage of leaf area occupied by pustules were recorded, as well as the length of the major pustule. The application and interpretation of statistical methods allowed to ratify as highly resistant PR980, resistant Ja64-11 and as susceptible My5514. The cultivars SP70-1284 (moderately resistant), C88-380 (moderately susceptible) and C323-68 (susceptible) are included as new standards. They are reclassified to C334-64 (moderately susceptible), Ja60-5 and B4362 (highly susceptible).

Keywords

• Puccinia melanocephala
• resistance
• evaluation
• diseases