Li Xuan, Leung Kelley
Department of Entomology-College of Plant Protection, Nanjing Agricultural University, Nanjing, China.
Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands.
Pest Manag Sci. 2025 Mar;81(3):1469-1477. doi: 10.1002/ps.8548. Epub 2024 Dec 23.
Intentionally impairing the fecundity of mass-reared insects has important utility in controlling pest species. Typically, sterilized individuals are competed against wild counterparts, reducing pest population size. A novel consideration is creating biocontrol agents with lower reproductive capacity that are less likely to establish permanently or admix with wild populations, which are both emerging as legal barriers. Hymenopterans have diploid females, but archetypically infertile polyploid triploid females occur for various parasitoid species. As a first test of polyploid utility for these biocontrol concerns, we assessed the species with the best characterized polyploid biology, the gregarious idiobiont Nasonia vitripennis, for triploid female host-killing ability on pupal blowfly hosts (Calliphora vomitoria).
We examined four polyploid lines: the old Whiting polyploid line (WPL) derived from a spontaneous mutation, and new polyploid lines made through RNAi knockdown of sex determination genes transformer, transformer-2 and wasp-overruler-of-masculinization. For diploid and triploid females of each polyploid line, and control diploids of the STDR and oyster lines used to maintain them, we measured lifetime number of hosts killed; lifetime number of hosts that produced at least one offspring; the percentage of the hosts killed and the percentage of hosts that produced offspring out of those offered; and lifespan. For all lines, triploids produced viable offspring in far fewer hosts than their diploid counterparts (≤70% less). Surprisingly though, they killed as many or more hosts than diploids over similar lifespans. The offspring production ability of the WPL triploid was half that of the other lines, but lines varied only slightly in the number of hosts killed (±10) among the polyploids.
The ability of reproductively impaired triploids to kill as many hosts as fertile diploids demonstrate high biocontrol utility for polyploidized females, and downstream potential for reducing ecological risk. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
有意降低大量饲养昆虫的繁殖力在控制害虫物种方面具有重要作用。通常，绝育个体与野生个体竞争，从而减少害虫种群数量。一个新的考虑因素是创造繁殖能力较低的生物防治剂，这类生物防治剂不太可能永久定殖或与野生种群混合，而这两个问题都正在成为法律障碍。膜翅目昆虫具有二倍体雌性，但各种寄生蜂物种通常会出现典型的不育多倍体三倍体雌性。作为对多倍体在这些生物防治问题上实用性的首次测试，我们评估了具有最明确多倍体生物学特征的物种——群居型静息寄生蜂丽蝇蛹集金小蜂，研究其三倍体雌性对蝇蛹寄主（反吐丽蝇）的杀寄主能力。
我们研究了四个多倍体系：源自自发突变的旧的怀廷多倍体系（WPL），以及通过RNA干扰敲除性别决定基因transformer、transformer - 2和黄蜂雄性化抑制基因而产生的新多倍体系。对于每个多倍体系的二倍体和三倍体雌性以及用于维持它们的STDR系和牡蛎系的对照二倍体，我们测量了一生杀死的寄主数量；一生产生至少一个后代的寄主数量；杀死的寄主百分比以及所提供寄主中产生后代的寄主百分比；以及寿命。对于所有品系，三倍体在比其二倍体对应个体少得多的寄主中产生可存活后代（少70% 或更多）。然而，令人惊讶的是，在相似的寿命期间，它们杀死的寄主数量与二倍体相同或更多。WPL三倍体的后代生产能力是其他品系的一半，但在多倍体中，各品系杀死的寄主数量仅略有差异（±10）。
繁殖能力受损的三倍体与可育二倍体杀死同样多寄主的能力表明，多倍体雌性具有很高的生物防治效用，并且在降低生态风险方面具有潜在的应用前景。© 2024作者。《害虫管理科学》由约翰·威利父子有限公司代表化学工业协会出版。
