桔小实蝇实验种群对敌百虫、高效氯氰菊酯和阿维菌素的抗性增长规律

Development of resistance to trichlorophon, alphamethrin,and abamectin in laboratory populations of the oriental fruit fly,Bactrocera dorsalis (Hendel)(Diptera:Tephritidae)

桔小实蝇Bactrocera doralis（Hendel）是华南地区水果蔬菜上重要害虫,近年来暴发成灾,造成巨大的经济损失。使用化学杀虫剂是防治该虫的重要方法。在长期、频繁接触杀虫剂条件下该虫的抗药性产生、发展规律等问题值得深入研究。本文采用LC50、LC80-90两种剂量汰选成虫、幼虫,研究了桔小实蝇对敌百虫、高效氯氰菊酯和阿维菌素3种药剂的抗性增长规律。通过不接触药剂继代饲养获得了对3种杀虫剂的敏感品系,建立了毒力回归方程,明确了毒力敏感基线LC50分别为1.6024mg/L,3.0964mg/L和0.6074mg/L。不同药剂种类、不同汰选方式时桔小实蝇的抗药性发展速度是不同的。以成虫死亡率50%左右作为选择压力,桔小实蝇对敌百虫的抗性发展最快,汰选至14代抗性增长至84.6倍;其次是高效氯氰菊酯,抗性增长至27.1倍;而对阿维菌素的抗性仅上升至7.7倍。在成虫和幼虫80%~90%死亡率左右的选择压力下,桔小实蝇对高效氯氰菊酯的抗性发展最快,汰选14代后抗性增长至125.4倍;其次是敌百虫,抗性增大至49.9倍;对阿维菌素抗性增长相对较缓慢,11代后为17.9倍。在成虫80%~90%死亡率左右的选择压力下,汰选14代、14代、11代后桔小实蝇对高效氯氰菊酯、敌百虫、阿维菌素分别增大至58.7倍、37.6倍、11.9倍。对成虫、幼虫均进行汰选桔小实蝇抗药性发展更快。建立了不同汰选方式时桔小实蝇实验种群汰选代数与对3种杀虫剂的抗性程度之间的关系方程,其中高效氯氰菊酯、敌百虫处理符合韦布尔曲线模型,阿维菌素处理符合幂曲线方程。

The oriental fruit fly, Bactrocera dorsalis （Hendel） is an important pest on fruits and vegetables of southern China. It caused huge economic losses in recent years. The use of chemical pesticides have been the important means for controlling the pest. The resistance emergence and development for B. dorsalis in the long-term and frequent exposure to pesticides were worthy of in-depth study. In this study, two dosages of LC50 and LC80-90 were employed to the adult and the larva for selecting resistant strains to trichlorophon, alphamethrin and abamectin, and the growth of resistance to the three insecticides were studied. Sensitive strains to the three insecticides were obtained through continuous breeding without contact of the insecticides, and toxicity regression equation were established. The sensitive baseline toxicity LC50 of the three insecticides were 1.6024 mg/L, 3.0964 mg/L, and 0.6074 mg/L, respectively. Different resistance of B. dorsalis developed depending on different pesticide types and selection approaches. The resistance to trichlorophon was the highest in three insecticides when using 50% dose-mortality of adult population as a selected pressure, the resistance increased 84.6-fold after treatment for fourteen generations, the resistance to alphamethrin increased 27.1-fold, while the resistance to abamectin only increased 7.7-fold. When 80% -90% dose-mortality to the adults and the larvae was applied, the resistance to alphamethrin increased 125.4-fold, the resistance of trichlorophon increased 49.9-fold after fourteen generations, while the resistance to abamectin increased comparatively slowly 17.9-fold after eleven generations. When 80% -90% dose-mortality to the adults was applied, the resistance to alphamethrin, trichlorophon and abamectin increased 58.7-fold, 37.6-fold, 11.9- fold, respectively. The resistance of B. dorsalis developed the fastest in both the adults and the larvae treated with pesticides. Under different selections and based on the extent of the relationship of experimental population of B. dorsalis and three kinds of pesticides, the resistance equations were established, of which alphacypermethrin and trichlorfon treatment curves conform to Weibull model, while abamectin treatment curve conforms to the power curve equation.