稻虱红单节螯蜂寄生不同虫龄白背飞虱对二者发育表现的影响

Influence of parasitism at different host stages on the developmental performance of both the parasitoid Haplogonatopus apicalis( Hymenoptera: Dyrinidae) and its host Sogatella furcifera( Hemiptera:Delphacidae)

【目的】为了解稻虱红单节螯蜂Haplogonatopus apicalis与白背飞虱Sogatella furcifera间的互作关系,开展了稻虱红单节螯蜂在白背飞虱不同龄期寄生时,对寄主及其自身发育表现影响的研究。【方法】在室内25℃条件下,观察了被寄生的白背飞虱各龄若虫及其寄生蜂稻虱红单节螯蜂的发育表现。【结果】白背飞虱2,3,4和5龄若虫被寄生后,当龄及其后各龄的历期均显著延长;2和3龄若虫被寄生后,成虫羽化率仅分别为54.29%和60.95%,显著低于在4和5龄若虫被寄生后的成虫羽化率(分别为96.20%和100%)。稻虱红单节螯蜂寄生白背飞虱5龄若虫后的发育历期(23.77 d)显著短于寄生2龄若虫后的发育历期(27.77 d);寄生3龄若虫的成蜂羽化率最高,为56.19%;而寄生5龄若虫的羽化雄蜂比例最高,为77.12%。【结论】稻虱红单节螯蜂寄生可使白背飞虱若虫发育历期显著延长,白背飞虱2和3龄若虫是稻虱红单节螯蜂发育的适宜寄主。

[Aim]In order to understand the interaction between the parasitoid Haplogonatopus apicalis and its host white-backed planthopper（ WBPH）,Sogatella furcifera,the effects of parasitism on the developmental performance of both H. apicalis and S. furcifera were studied. [Methods]Developmental time of S. furcifera nymphs parasitized at different instars and developmental duration from egg to adult of H. apicalis in different instars of S. furcifera nymphs were observed at 25℃ in the laboratory. [Results]The developmental durations of the 2nd,the 3rd,the 4th,or the 5th instar nymphs of the host S.furcifera were significant prolonged when they were parasitized by H. apicalis wasps. When the hosts were parasitized at the 2nd and the 3rd instars,the eclosion rates of S. furcifera adults were 54. 29% and60. 95%,respectively,which were much lower than those parasitized at the 4th and the 5th instars（ 96. 20% and 100%,respectively）. The generation time of H. apicalis parasitizing on the 5th instar nymphs of the host（ 23. 77 d） was obviously shorter than that of the parasitoids parasitizing on the 2 nd instar nymphs（ 27. 77 d）. The parasitoid showed the highest eclosion rate（ 56. 19%） when the parasitism was at the 3rd instar nymphal stage of the host,and the highest male adult proportion（ 77. 12%） when the parasitism was at the 5th instar nymphal stage of the host. [Conclusion]The developmental duration of S. furcifera nymphs is obviously delayed by parasitization of H. apicalis. The2 nd and the 3rd instar nymphs of S. furcifera are the optimum host stages for H. apicalis.