Akbar W, Ottea J A, Beuzelin J M, Reagan T E, Huang F
Department of Entomology, Louisiana State University AgCenter, Baton Rouge, LA 70803, USA.
J Econ Entomol. 2008 Dec;101(6):1903-10. doi: 10.1603/0022-0493-101.6.1903.
Varying susceptibility to tebufenozide was recorded in the sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Crambidae), collected from Louisiana sugarcane locations with different selection pressures. Results from diet incorporation bioassays with tebufenozide indicated significant increases in LC50 (3.78-fold) and LC90 (7-fold) values for a colony from Duson (DU), an area with higher selection pressure, compared with a colony from Alexandria (ALEX), an area with no selection pressure. Differences were not detected in LC50 values among colonies from areas where use of tebufenozide was discontinued or rotated with other chemistries. Selections with tebufenozide of DU larvae over 12 generations resulted in a highly resistant colony (DU-R) with 27.1- and 83.3-fold increases in LC50 and LC90 values, respectively. Comparison of pupal weight, days to pupation, and emergence after exposure to an equitoxic (LC20) concentration of tebufenozide revealed a decrease in pupal weight (34 and 33% for males and females, respectively), and an increase in days to pupation (47 and 40% for males and females, respectively), and emergence (43 and 33% for males and females, respectively) for the DU-R colony compared with the parent DU colony. Fecundity of DU-R females decreased to 72 eggs per female compared with 180 (DU) and 261 (ALEX). Egg viability of the ALEX and DU colonies was 61 and 56%, respectively, whereas only 27% of eggs laid by females from the DU-R colony hatched. These results are discussed in terms of their practical implications for control of D. saccharalis in Louisiana sugarcane.
在从路易斯安那州不同甘蔗种植地采集的甘蔗螟虫，即黄螟（Diatraea saccharalis (F.)，鳞翅目：草螟科）中，记录到了对虫酰肼的易感性差异。这些种植地具有不同的选择压力。用虫酰肼进行饲料掺入生物测定的结果表明，与来自无选择压力地区亚历山大（ALEX）的群体相比，来自选择压力较高地区迪松（DU）的群体的半数致死浓度（LC50）值显著增加（3.78倍），半数致死浓度（LC90）值显著增加（7倍）。在停用虫酰肼或与其他化学药剂轮换使用的地区的群体中，未检测到LC50值存在差异。用虫酰肼对DU幼虫进行12代的选育，得到了一个高抗性群体（DU-R），其LC50和LC90值分别增加了27.1倍和83.3倍。在暴露于等毒性（LC20）浓度的虫酰肼后，对蛹重、化蛹天数和羽化情况进行比较，结果显示，与亲本DU群体相比，DU-R群体的蛹重下降（雄性和雌性分别下降34%和33%），化蛹天数增加（雄性和雌性分别增加47%和40%），羽化天数增加（雄性和雌性分别增加43%和33%）。DU-R雌性的繁殖力降至每只雌性72枚卵，而DU为180枚，ALEX为261枚。ALEX和DU群体的卵孵化率分别为61%和56%，而DU-R群体雌性所产的卵只有27%孵化。本文从这些结果对路易斯安那州甘蔗中黄螟防治的实际意义方面进行了讨论。
