YIELD LOSS IN EAST-AFRICAN HIGHLAND BANANA (MUSA SPP., AAA-EA GROUP) CAUSED BY THE BANANA WEEVIL, COSMOPOLITES-SORDIDUS GERMAR

Yield loss in highland banana caused by the banana weevil, Cosmopolite s sordidus, was studied in field trials in Uganda. Weevils were releas ed at the base of banana mats 9 months after planting. Weevil populati ons, corm damage, plant growth and yield were assessed over four crop cycles. The effect of damage was greater on bunch weight than on plant growth and rate of development. Yield loss increased with crop cycle and ranged from 5% in the first cycle to 44% in the fourth cycle. The cumulative effect of heavy damage sustained over several crop cycles r esulted in greater reduction in bunch weight than that inflicted by si milar levels of damage in a single cycle. The data suggest that C. sor didus damage is a leading cause of highland banana decline and disappe arance in central Uganda. (C) 1998 Elsevier Science Ltd. All rights re served