副珠蜡蚧阔柄跳小蜂对蓝色长盾金小蜂寄生橡副珠蜡蚧的干扰作用

为明确副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae Zhang & Huang对蓝色长盾金小蜂Scutellista caerulea Fonscolombe寄生橡副珠蜡蚧Parasaissetia nigra Nietner的干扰作用, 于室内观察了寄主不同成虫阶段(产卵前期和产卵期)?副珠蜡蚧阔柄跳小蜂接蜂数量(3?10?20头和30头)?两种蜂接蜂间隔时间(2?4?6 d和8 d)等因素对两种寄生蜂寄生率和产卵量的影响?结果表明, 寄主发育阶段对蓝色长盾金小蜂产卵量和寄生率均无显著影响?随着副珠蜡蚧阔柄跳小蜂接蜂数增加, 蓝色长盾金小蜂的产卵量有所增加, 但增加不显著?副珠蜡蚧阔柄跳小蜂接蜂数为3~30头时, 蓝色长盾金小蜂寄生率均高于副珠蜡蚧阔柄跳小蜂; 接入副珠蜡蚧阔柄跳小蜂后再接蓝色长盾金小蜂时, 两种寄生蜂接蜂间隔时间对蓝色长盾金小蜂的寄生率及产卵量影响明显, 间隔2 d时蓝色长盾金小蜂产卵量最高, 为21.3粒; 间隔4 d时, 蓝色长盾金小蜂寄生率最高, 为58.89%; 但间隔8 d时蓝色长盾金小蜂的产卵量和寄生率下降至最低?研究结果表明, 接入副珠蜡蚧阔柄跳小蜂后再接蓝色长盾金小蜂时, 间隔时间在4 d内对蓝色长盾金小蜂没有影响, 间隔时间超过4 d时对蓝色长盾金小蜂有明显干扰, 试验结果可以为合理避免这两种寄生蜂种间竞争提供依据?

Interference of the parasitism of Scutellista caerulea on Parasaissetia nigra by Metaphycus parasaissetiae

To clarify the interference on the parasitism of Scutellista caerulea Fonscolombe on Parasaissetia nigra Nietner by Metaphycus parasaissetiae Zhang & Huang, we investigated the influence of the factors, such as host developmental stage (pre-oviposition and oviposition), the number of introduced M. parasaissetiae females (3, 10, 20 and 30 individuals), and the interval time between introduction of two wasp (2, 4, 6 d and 8 d) on the parasitism rate and oviposition of the two parasitoids. The results showed that the host developmental stage had no significant effect on the fecundity and parasitism rate of S. caerulea. The fecundity of S. caerulea females increased with increasing number of M. parasaissetiae females, but the increase was not significant. When the number of introduced M. parasaissetiae was 3-30, the parasitism rate of S. caerulea was higher than that of M. parasaissetiae. The interval time between two introductions of the parasitic wasp had a significant effect on the parasitism rate and the fecundity of S. caerulea when introducing M. parasaissetiae first. The maximum number of eggs laid by S. caerulea appeared in the group with an interval time of 2 d, which was 21.3 eggs, and the parasitism rate was the highest in the group with an interval time of 4 d, which was 58.89%. However, the fecundity and parasitism rate of S. caerulea dropped to the lowest when interval time of introduction was 8 d. These results suggested that there is insignificant effect on S. caerulea when interval time shorter than 4 d between first introduction of M. parasaissetiae and then S. caerulea, but there was an obvious interference on S. caerulea when the interval time exceeded 4 d. These results can provide a basis for reasonably avoiding competition between these two parasitic wasp species.