橡副珠蜡蚧及其寄生蜂过冷却点的测定

Determination of the supercooling point of Parasaissetia nigra and its parasitoid Metaphycus parasaissetiae

室内测定了橡副珠蜡蚧Parasaissetia nigra及其寄生蜂副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae的过冷却点和结冰点。结果表明:橡副珠蜡蚧各虫态的过冷却点和冰点以卵最低分别为-21.7℃和-16.7℃;以少量幼虫出壳期成虫的过冷却点和冰点最高,为-5.7℃和-1.8℃,各虫态过冷却点按从低到高的顺序排列为:卵<1龄若虫<3龄若虫<2龄若虫<初期成虫<褐色期成虫<初产卵期成虫<少量幼虫出壳期成虫。副珠蜡蚧阔柄跳小蜂的蛹期过冷却点均显著低于雌、雄成峰,分别为-21.3℃、-11.8℃和-9.1℃,而三者冰点差异不显著,分别为-8.4℃、-8.5℃和-10.2℃。以上结果为副珠蜡蚧阔柄跳小蜂应用提供了理论依据。

Laboratory experiments were conducted to examine the supercooling point（ SCP） and the freezing point for the Parasaissetia nigra and its parasitoid Metaphycus parasaissetiae. The results indicated that the SCP and the freezing point of egg of P. nigra Nietner were the lowest,which were- 21. 7℃ and- 16. 7℃,respectively,while the SCP and the freezing point of the hulling adult were the highest,which were- 5. 7℃ and- 1. 8℃,respectively. The sequence of SCP from low to high is egg the 1stinstar larva the 3rdinstar larva the 2ndinstar larva the initial adult the brown adult 1- 2 d after oviposit A few hulling larva. The SCP of the pupa of M. parasaissetiae was the lowest among all the developmental stages and the difference was significant,which were- 21. 3℃（ pupal stage） 、- 11. 8℃（ female adult） and- 9. 1℃（ male adult）,respectively. However,there were no significant difference among their freezing point,which were- 8. 4℃ 、- 8. 5℃ and- 10. 2℃,respectively. These results will support theoretically for application of M. parasaissetiae.