短期高温对感染Wolbachia的松毛虫赤眼蜂发育和繁殖的影响

感染了沃尔巴克氏体Wolbachia的松毛虫赤眼蜂Trichogramma dendrolimi Matsumura营孤雌产雌生殖方式,但高温可能影响这一特性。为了模拟该赤眼蜂在田间遇到短期高温后的受影响情况,研究了柞蚕卵繁殖的Wolbachia感染了Wolbachia的松毛虫赤眼蜂孤雌产雌品系,于蛹中期和蛹后期经历6h32,35,38℃高温单次冲击处理,对当代羽化出蜂率、单卵出蜂数、单卵雌蜂率、寿命4个指标和处理子代羽化出蜂率、有效繁殖个体、单卵出蜂数、单卵雌蜂率4个指标的影响。结果表明,短期高温刺激会对孤雌产雌的松毛虫赤眼蜂产生不利影响,尤其是38℃高温不利影响明显,主要表现在羽化出蜂率和单卵出蜂数两指标明显降低;高温冲击对子代蜂各指标影响不明显。2代赤眼蜂均未有雄峰出现,表明短期高温冲击不能对Wolbachia调控其宿主生殖方式的作用产生影响。

Effect of high temperature shock on Trichogramma dendrolimi infected by Wolbachia

Trichogramma dendrolimi Matsumura infected by Wolbachia has a character—thelytokous reproduction. However, high temperature may affect this character. To simulate this condition in field, a test single heat shocks (32, 35 and 38℃)for 6 hours was applied to middle stage and late stage of pupae of T. dendrolimi infected by Wolbachia. A series of data was recorded including the percentages of adult emergence rate, number of wasps per host egg, female ratio and longevity as well as the number of wasps with parasitization, percent emergence, number of wasps per host egg and female ratio in the next generation. The results showed the high temperature shocks had negative effect to both middle stage and late stage of pupae, especially at 38℃.At this temperature, emergence rate and number of wasps per host egg were remarkably reduced. The sensitive level between middle stage and late stage of pupae has no remarkable difference. For the progeny generation, all parameters as a whole seem to be little affected by the heat shock experienced in the parent generation. In the two generations wasps, there is no male emergence. This indicates that short high temperature shocks can not influence the action of Wolbachia manipulating reproduction of their hosts.