SEASONAL INCIDENCE OF LIRIOMYZA-HUIDOBRENSIS (DIPTERA, AGROMYZIDAE) AND ITS PARASITOIDS ON VEGETABLES IN INDONESIA

The leaf miner Liriomyza huidobrensis (Diptera: Agromyzidae) was first reported in Java, Indonesia in 1994. Since then it has invaded the ma jor vegetable-producing regions of Java and Sumatra. Surveys indicate that this pest attacks over 20 species of vegetable, ornamental and we ed hosts. The parasitoid Hemiptarsenus varicornis (Hymenoptera: Euloph idae) was collected from L. huidobrensis-infested plant material in al l the sites, and on 19 of the 20 cultivated species surveyed. Potatoes were the most severely attacked crop and nearly 100% yield reduction was observed in some fields. The seasonal activity of the leafminer an d its parasitoids was monitored on potato, scallions, and broccoli by collecting weekly leaf samples and holding them in containers in the l aboratory until the flies or parasitoids emerged. Leafminer population s were most severe in potato, especially towards the end of the wet se ason (March 1996). Scallions and broccoli produced higher numbers of H . varicornis than leafminers.