烟夜蛾滞育蛹和非滞育蛹的耐寒性

The cold tolerance of the diapause and non-diapuse pupae of Helicoverpa assulta.

对烟夜蛾Helicoverpa assultaGuen?e不同日龄滞育蛹和非滞育蛹的过冷却点和结冰点测定结果表明,在预蛹至5日龄蛹期,过冷却点和结冰点均逐渐下降。在预蛹期和3日龄蛹期,滞育蛹的过冷却点与非滞育蛹差异不显著;5日龄蛹时,滞育蛹和非滞育蛹的过冷却点分别下降至(-15.7±1.8)℃和(-13.5±1.2)℃,结冰点分别降至(-12.7±2.7)℃和(-9.5±1.3)℃,两类蛹间的差异均达极显著水平。自然越冬后,滞育蛹的存活率显著高于非滞育蛹,在土壤不同深处越冬的蛹的存活率存在差异,距土表15cm深的蛹存活率最高。

The supercooling point and freezing point were surveyed in diapause and non-diapuse pupae of Helicoverpa assulta Guenée in different developing stages. The results showed that supercooling point and freezing point decreased from pre-pupae to 5-day pupae period. During the stage of pre-pupae and 3-day pupae, there was no significant difference between the supercooling point of diapause pupae and that of non-diapuse pupae. In the stage of 5-day pupae, the supercooling points of diapause pupae and non-diapuse pupae were （ - 15.7 ± 1.8）℃and （ - 13.5 ± 1.3）℃, respectively, and the freezing points were （ - 12.7 ± 2.7）℃ and （ - 9.5 ± 1.3）℃ respectively, both of which were different. The survival rate of diapause pupae was significantly higher than that of non-diapause pupae after overwintering in the field, and survival rate of pupae varied with the depth of soil, among which the pupae in 15cm depth of soil had the highest survival rate.