Vector transmission of Banana streak virus in the screenhouse in Uganda

Although mealybug transmission of Banana streak Virus (BSV) by Planococcus citri and Saccharicoccus sacchari has been demonstrated elsewhere, these me alybugs have not been identified on bananas in Uganda and their role and th at of other agents in BSV transmission is not well documented. Insect sampl es were collected from banana farms in sites with low, moderate and high BS V infections in Uganda. Subsequently, live mealybugs and aphids were again collected and used in acquisition, retention and transmission tests, and BS V diagnosed using TAS-ELISA. Dysmicoccus brevipes (pineapple mealybug), S. sacchari (sugarcane mealybug) and Pentalonia nigronervosa (banana aphid) we re the most abundant insect species from banana fields sampled. Abundance o f D. brevipes was positively and significantly correlated with BSV incidenc e unlike that of P. nigronervosa. Transmission studies in the screenhouse s howed that mealybugs acquired BSV one day after feeding on virus sources an d approached optimum acquisition after the third day. Pineapple and sugarca ne mealybugs retained BSV up to 5 days from the day of transfer from the vi rus source. BSV was first detected in the recipient banana plants 4 wk afte r transmission using pineapple mealybug and 6 wk after inoculation using su garcane mealybug. Under screenhouse conditions, both mealybugs therefore ap pear to transmit BSV semipersistently.