Control of the sugarcane borers, Diatraea saccharalis and Diatraea impersonatella (= D. flavipennella) (Lepidoptera: Crambidae), in Brazil, is based on mass release of the larval parasitoid Cotesia flavipes (Hymenoptera: Braconidae). However, this method does not prevent some pupae of these borers from completing development and recolonizing the crop. Thus, additional control is required. This study investigated the parasitoid Tetrastichus howardi (Hymenoptera: Eulophidae) to control pupae of sugarcane borers, especially D. impersonatella. Regardless of larval instar and species, no larval parasitism occurred within 24 h of exposure. Nevertheless, a longer exposure period (ca. 96 h) resulted in parasitism of older larvae. Approximately 90% of pupae of both borers were parasitized by T. howardi within 24 h of exposure, and the parasitoid produced a similar number of offspring with >90% females. The developmental time of T. howardi parasitizing D. impersonatella pupae was delayed ~2 days from that of in D. saccharalis. No-choice trails revealed that parasitoid females took longer to start probing larvae compared to pupae. Likewise, when larvae and pupae were offered simultaneously (choice test), the latter represented the first choice of about 92% T. howardi females. The elapsed time to first attack was less on pupae than on larvae, whereas the number of attacks and probing time was greater on pupae. In addition, parasitism on D. impersonatella pupae was higher than on larvae feeding on artificially infested sugarcane seedlings. These results suggest that T. howardi prefers to parasitize the pupal stage and has the potential to be used as a biological control agent to complement the control of sugarcane bores.

在巴西，对甘蔗bore虫，白粉病和黄粉虫（D. flavipennella）（鳞翅目：Crammbidae）的控制是基于幼体寄生的拟南芥（Cotesia flavipes）（膜翅目：Braconidae）进行的。但是，这种方法并不能阻止这些bore的某些some完成发育并重新定殖。因此，需要额外的控制。这项研究调查了拟寄生蜂（Tetrastichus howardi）（膜翅目：Eulophidae），以控制甘蔗bore（尤其是D. impersonatella）的p。。不论幼虫龄和种类，在接触后24小时内均未发生幼虫寄生虫。然而，较长的暴露时间（约96小时）导致年龄较大的幼虫寄生。在暴露的24小时内，约瑟氏。的大约90％的bore被霍华德氏菌（T. howardi）寄生，并且该寄生虫产生的后代数量相似，雌性> 90％。的发育时间T. howardi寄生于D. impersonatella蛹被推迟从的〜2天蔗。没有选择的线索表明，与p相比，寄生类雌性开始探测幼虫所花费的时间更长。同样，当同时提供幼虫和p（选择测试）时，后者代表约92％的第一选择T.霍华迪女性。在p上第一次发作所花费的时间少于在幼虫上，而在p上发作的次数和探测时间更长。此外，imp虫D. impersonatella pupae的寄生率高于人工感染甘蔗幼苗的幼虫。这些结果表明，霍华德氏菌更喜欢寄生化stage期，并有可能被用作生物防治剂以补充对甘蔗孔的控制。