钩纹皮蠹不同虫态过冷却点及结冰点的测定

Supercooling points and freezing points at different stages of Dermestes ater De Geer

为初步明确钩纹皮蠹Dermestes ater De Geer不同虫态的抗寒能力,本文运用智能昆虫过冷却点测定仪及配套软件测定钩纹皮蠹幼虫、蛹和成虫的过冷却点及结冰点,比较不同虫态过冷却点和结冰点的差异,以期为钩纹皮蠹的越冬区划分、发生期预测和虫害防控等提供理论依据。结果表明,钩纹皮蠹3日龄蛹的平均过冷却点最低,为-24.31℃,1龄幼虫平均过冷却点最高,为-16.34℃,其余虫态平均过冷却点依次为老熟幼虫(-24.04℃)<5日龄蛹(-23.84℃)<1日龄蛹(-23.01℃)<7日龄蛹(-19.53℃)<7龄幼虫(-19.16℃)<5龄幼虫(-18.75℃)<3龄幼虫(-18.43℃)<成虫(-18.25℃);老熟幼虫的平均结冰点最低,为-18.41℃,5龄幼虫平均结冰点最高,为-10.84℃,其余虫态平均结冰点依次为3日龄蛹(-18.26℃)<1日龄蛹(-17.13℃)<5日龄蛹(-16.87℃)<1龄幼虫(-14.66℃)<成虫(-14.55℃)<7日龄蛹(-13.20℃)<3龄幼虫(-12.96℃)<7龄幼虫(-12.38℃)。钩纹皮蠹蛹和老熟幼虫有较强的抗寒能力,但幼虫和成虫的抗寒能力较弱。

In order to determine the cold resistance of Dermestes ater De Geer,the intelligent insect supercooling point tester and the matching software were used to measure the supercooling point and freezing point of its larvae,pupae and adults,and the differences between the supercooling point and the freezing point of different insect states were compared,so as to provide a theoretical basis for division of overwintering areas,occurrence forecast and pest control.The results showed that the 3-day-old pupa had the lowest average supercooling point(-24.31℃);the first-instar larva had the highest average supercooling point(-16.34℃),and the average supercooling points of the other insect states were as followed:mature larva(-24.04℃)<5-day-old pupa(-23.84℃)<1-day-old pupa(-23.01℃)<7-day-old pupa(-19.53℃)<the seventh-instar larva(-19.16℃)<the fifth-instar larva(-18.75℃)<the third-instar larva(-18.43℃)<adult(-18.25℃).The mature larva had the lowest average freezing point(-18.41℃);the fifth-instar larva had the highest average freezing point of-10.84℃,and the average freezing points of the other insect states were as followed:3-day-old pupa(-18.26℃)<1-day-old pupa(-17.13℃)<5-day-old pupa(-16.87℃)<the first-instar larva(-14.66℃)<adult(-14.55℃)<7-day-old pupa(-13.20℃)<the third-instar larva(-12.96℃)<the seventh-instar larva(-12.38℃).The pupae and mature larvae showed stronger cold resistance,but the cold resistance of larvae and adults were weaker.