Characteristic Damages Caused by and Preference on Three Varieties of Bananas of Pest Insect,Thrips hamaiiensis

At the banana planting stationin Zhangzhou,characteristic damages caused by the pest insect,Thrips hamaiiensis,as well as the insect's eating preference on the buds and fruit lets of 3varieties of Musa nana were studied.The results showed that the first and second instar nymphs and adults of T.hamaiiensis made the most damages to the banana plants.They rasping-sucked or oviposited on the ovary,sex flower,outer bract of the bud,and the fresh-tender part of the fruitlet on a plant.The insect populations found on 3equally divided vertical parts of the outer bract of the bud differed and ranked as the upper part>middle part>lower part.The populations on 4layers of the outer bracts ranked as the second layer>first layer>third layer>fourth layer.The numbers of damage spots on the ovaries of 3sex flowers were greater on the female flowers than the neutral or male flowers.The eating preferences of the insects on the buds and fruitlets were M.AAA Group Red green>M.AAB Group Fenjiao>M.AAA Group Giant Cavendish Williams.