Ecological studies on sweet potato leaf miner (Bedellia ferenodes) II. Studies on the population dynamics of sweet potato leaf miner and its control.
Bedellia terenodes Meyr., a pest of sweet potato, could be found throughout the year in Taiwan, but especially in the dry season (November-March). Populations reached a peak in March and were lowest in the rainy season. The summer crop suffered more damage than the autumn one. Populations were higher in the counties of Chang-Hua and Yun-Lin than elsewhere, and were found from sea level to an altitude of 1400 m. Sweet potato varieties with light-green leaves or broad leaf-blades suffered less damage than others. Other food-plants included Ipomoea aquatica, I. obscura and I. palmata. Natural enemies found were Apanteles sp. and Euborellia pallipes (Shir.). Fenitrothion (as 50% Sumithion to 1000 parts water) and methomyl (as 90% Lannate to 1800 parts water) were effective in controlling the leaf-miner.