高温对田间小菜蛾DNA损伤及4种抗药性相关酶系活性的抑制

研究了高温对福州上街菜田小菜蛾成虫4种抗药性相关酶系活性的影响。与饲养在25℃下的小菜蛾相比，33．5~C或40℃处理72h导致小菜蛾基因组DNA出现DNA凋亡特征梯度化条带。33~C饲养小菜蛾4、8、12或24h对小菜蛾成虫乙酰胆碱酯酶（AChE）和羧酸酯酶（CarE）活性无显著影响，但33℃饲养小菜蛾12或24h导致小菜蛾成虫谷胱甘肽s转移酶（GSTs）酶活性和细胞色素P450含量显著下降。36℃、24h可导致AChE活性显著下降，36℃、12h和24h可导致CarE活性显著下降，36℃、4h，8h，12h和24h可导致GST活性和细胞色素P450含量显著下降。总体上，高温对CarE、GSTs和细胞色素P450的抑制作用大于对AChE的影响，此外，3CC对AChE、CarE、GSTs酶活性和细胞色素P450含量的抑制作用大于33℃的抑制作用。

Damage of genomic DNA and the inhibition of four enzymes involved in insecticide resistance due to high temperatures in field Plutella xylostella

The effects of high temperature on acetylcholinesterase （ AChE ）, carboxyesterases （ CarE ） and glutathione S-transferase （GST） activities, as well as on cytochrome P450 content, were studied in adult PluteUa xylostella （DBM） collected from fields in Shangjie, Minhou, Fujian, China. Compared to insects reared at 25 °C, significant genomic DNA damage occurred when the adult DBM were pretreated at 33.5°C or 40° C for 72 h. Neither AChE nor Care activities were inhibited when the adults were pretreated at 33°C for 4, 8, 12 or 24 h. However, a significant inhibition of GST activity and cytochrome P450 content occurred when the adults were pretreated at 33°C for 12 and 24 h. The activities of ACHE, CarE and GST and/or eytochreme P450 content were significantly inhibited when the adults were reared at 36 °C for the following time intervals： 24 h （for ACHE} ; 12 h and 24 h （for CarE} ; and 4 h, 8 h, 12 h and 24 h （for GST and P450）. In general, AChE activity was less inhibited by high temperatures relative to CarE, GST and P450. In addition, the inhibition of ACHE, CarE and GST activities, as well as of P450 content, increased with increases in the temperature and the treatment time.