OBSERVATIONS ON SOME INSECTS ASSOCIATED WITH SUGARCANE IN PUERTO RICO

Abstract

Survey work in 1935-36 on sugarcane insects of Puerto Rico, especially those which may transmit mosaic disease, is described. Previous work is cited; climate, geography, and methods are outlined briefly. Aphis maidis was found to be rather abundant on tasseled corn, sparingly present on several grasses, and scarce on cane. Hysteroneura setariae was moderately abundant on some grasses, occasional on cane along the south coast, and rare on cane elsewhere. Sipha flava was widespread on cane, sometimes injurious, and small numbers occurred on grasses. Carolinaia cyperi was found in moderate numbers on a sedge. A. maidis was most numerous in the rainy season, the other three in the dry season. Mealybugs were numerous, especially on mature cane. Saccharosydne saccharivora was widespread but seldom numerous on cane. Some minor insect notes are recorded. Aphis maidis seems likely to be important in mosaic dissemination, because more abundant in areas of rapid than of slow spread. Hysteronera and Carolinaia seem less likely to be important, and the other insects named seem unlikely to be implicated at all. Some aphids not breeding on grasses may be important.