元江芒果蓟马的危害特性及其防治

芒果蓟马是危害芒果十分严重的害虫，在元江发现有黄胸蓟马、褐蓟马、红蓟马危害芒果花序及果实。花穗受害率达100％，严重影响芒果的产量和质量。1992～1994年通过对蓟马生活史及消长规律的观察，掌握了蓟马在元江以芒果为寄主，1年发生8～9代，3月底至4月初为发生高峰期，至6月上旬后数量迅速下降，危害降低的危害特性。5种不同药剂的防效试验表明用24％万灵、21％灭杀毙、15％氧化乐果、40％速扑杀1000倍药液进行防治，防效达76．2％～83．6％。大田防效达77％以上，可有效控制多种蓟马的危害，花期连续喷撒3～4次，可保证花期座果。

Harm Characteristics and the Control of Thrips in Mangifera indica in Yuanjiang

Thrips are very harmful pests of Mangifera indica. Three thrips, namely Thrips hawaiiensis, Scirtothrips mangiferae priesmer and another unidentified one have been discovered in Yuanjiang County up to now, which do great harm to inflorescence and fruit of Mangifera indica. The percentage of suffered inflorescence can even reach 100%, therefore, the yield and quality of Mangifera indica have been influenced heavily. From 1992 to 1994, through observing on life cycle, growth and decline pattern of the thrips, it has been made clear that in Yuanjiang, Mangifera indica is the host of thrips, 8～9 generations appear within one year and the end of Marchto early April is the peak. The experiment on five chemicals shows the control effect of 24% Wanlin, 21% Miesabi, 15% omethoate and 40% Supusa (Dilution factor is 1000) can reach 76.2%～83.6%, and the control effect in the field can reach over 77%. Spraying continuously the chemicals 3～4 times in flowering period can guarantee fruit setting. Spraying 1～2 times in 25 days before fruit ripping can reduce the harm to fruit.