马铃薯甲虫自然种群抗寒能力测定

Cold hardiness of natural populations of the colorado potato beetle,Leptinotarsa decemlineata

为明确马铃薯甲虫自然种群的抗寒性,利用热敏电阻测定仪对马铃薯甲虫不同虫态过冷却点和冰点进行了测定。结果表明:不同虫态过冷却点和冰点之间存在显著性差异,其中以卵和成虫的过冷却点最低,分别为:(-13.73±0.93)℃和(-7.89±0.07)℃,显著低于其他虫态。3龄幼虫的过冷却点和冰点最高,分别为:(-6.21±0.08)℃和(-2.80±0.08)℃;过冷却点由低到高顺序为:卵<成虫<1龄幼虫<蛹<4龄幼虫<2龄幼虫<3龄幼虫;冰点由低到高的顺序为:卵<1龄幼虫<成虫<2龄幼虫<蛹<4龄幼虫<3龄幼虫;同一虫态个体间的过冷却点频次分布出现不同程度的变异,但均服从正态分布。研究结果为制定马铃薯甲虫在我国潜在分布和风险分析提供了科学依据。

The supercooling points and freezing points of the colorado potato beetle,Leptinotarsa decemlineata at all stages,were measured using a thermocouple.It showed that the supercooling points and freezing points were significantly different between adults,eggs,larvae and pupae,in which the eggs and adults had stronger cold hardness（-13.73±0.93 ℃ and-7.89±0.07 ℃） than other stages,and the differences were significant.The highest supercooling point and freezing point of the 3rd-instar larvae were-6.21±0.08 ℃ and-2.80±0.08 ℃,respectively.The sequence of supercooling points from low to high was egg,adult,the 1st-instar larva,pupa,the 4th-instar larva,the 2nd-instar larva and the 3rd-instar larva.And the sequence of freezing points from low to high was egg,the 1st-instar larva,adult,the 2nd-instar larva,pupa,the 4th-instar larva and the 3rd-instar larva.The supercooling point of L.decemlineata varied significantly among individuals,but followed a normal distribution.The results provide a scientific basis for the development of risk analysis and potential distribution of L.decemlineata.