Incidence of Brown Stripe Disease of Sugarcane in Puerto Rico

Abstract

In the recent disease survey over the Island of Puerto Rico, care was taken to record the incidence of brown stripe disease. The extent of infection observed varied with localities. At Caño Tiburones, San Sebastian, and Igualdad, varieties P.R. 980, P.R. 1028, P.R. 1018 x M. 336, and Eros were observed to be heavily affected by brown stripe. The apparent resistance and susceptibility of some 110 seedling selections from the cross combination P.R. 080 X M. 336 were recorded in the course of the survey. A study of the frequency and distribution of the brown stripe lesions on these selections indicates that the degree of resistance or susceptibility to the disease is not controlled by a single dominant factor, but seems to be polygenic in nature.