西花蓟马在低温下的生长发育和繁殖研究

为探明低温对西花蓟马[Frankliniellaoccidentalis(Pergande)]生长发育和繁殖的影响，全面了解西花蓟马的生活习性，为其综合防治提供依据。将西花蓟马分别置于5℃、10℃低温培养箱中，每天观察记录2种环境温度下西花蓟马的生长发育和繁殖情况。研究表明，5℃下西花蓟马不能完成生活史，卵不能正常孵化；1龄若虫可以发育到2龄，但2龄若虫不能继续发育至蛹；蛹能够发育至成虫但成虫不能产卵；10℃下西花蓟马能够完成生活史，但是发育历期显著延长。上述结果表明，低温导致西花蓟马的发育速度减慢，后代数量骤减，但西花蓟马转移至室温环境后，能够恢复正常生长，说明其具有很强的低温耐受性，防治中应充分注意西花蓟马的这一低温耐受特性，在早春温度回升和其种群数量开始上升时及时进行防治。

Development and Reproduction of Frankliniella occidentalis (Pergande) Under Conditions of Low Temperatures

In order to explore the influence of low temperature on the development and reproduction of Frankliniella occidentalis (Pergande), and to have a full knowledge of the pest in the work of IPM, F. occidentalis were reared under 5℃ and 10℃ respectively in the incubator and their development and reproduction were investigated and recorded. The results showed that F. occidentalis could not complete a life cycle at 5℃. The eggs could not be hatched, the first instar nymphs were able to develop into the second instars but unable to develop into pupae. The pupae could develop into adults but the adults could not lay eggs. When being placed under the condition of 10℃ , the thrips could complete a life cycle but showed a significant prolonged developmental time compared with that under 25℃. The results indicated that the low temperature resulted in delayed development and decreased fecundity of F. occidentalis. However, the thrips could return to normal growth when transferred from low temperature to room temperature, indicating that F. Occidentalis has strong tolerence to low temperature. In the control of this pest, it is necessary to pay attention to its tolerence to low temperature, and measures should be taken to prevent the burst of F. occidentalis when the temperture and the population begin to increase during the early spring.