Identification, Occurrence, and Distribution of Strains Sugarcane Mosaic in Puerto Rico

Abstract

Three strains of sugarcane mosaic, A, B, and D, described in Louisiana, were found to make up the bulk of the collections of the sugarcane mosaic virus in Puerto Rico. Strain B was most prevalent. It was the major strain found on B.H. 10(12), B. 34104, and M. 336. Strain D was equally abundant on B. 37161. B. 37161 showed some, resistance to mosaic in the field as compared with B. 34104. This may be due to some resistance to strain B. If B. 37161 is not kept free of mosaic, the preferred strain D may increase in it and render it more susceptible in the field. No marked geographic pattern of strain distribution was observed. Mechanical transmission of mosaic by the Sein method gave a better correlation with field reaction of varieties than did transmission by the Matz method. Strain A was most easily transmitted mechanically, while in the field strain B predominated in most varieties. Therefore, the vectors of Puerto Rico may be more efficient transmitters of strain B than of A.