α−三联噻吩对舞毒蛾幼虫的杀虫活性和生理生化影响

Insecticidal activity and physiological and biochemical effects ofα-terthienyl on Lymantria dispar larvae

为探究α−三联噻吩(α−terthienyl,α−T)对舞毒蛾Lymantria dispar 3龄幼虫的杀虫活性和生理生化影响,利用饲料混药法、分光光度法和HE染色法,分别测定α−T处理对舞毒蛾3龄幼虫的毒力及对幼虫生长发育、营养物质含量、抗氧化酶活性、中肠组织的影响。结果表明:α−T对舞毒蛾3龄幼虫处理72 h有良好的毒杀活性,亚致死浓度(LC20)和致死中浓度(LC_(50))分别为20.37,178.13μg/mL;LC20和LC_(50)的α−T处理舞毒蛾3龄幼虫72 h能够显著降低其体质量增长量,降低体内可溶性蛋白、碳水化合物、海藻糖、脂质的含量;LC_(50)的α−T对舞毒蛾幼虫中肠过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性具有显著的抑制作用,能够损伤幼虫中肠组织,产生显著的病理变化。α−T能够通过降低舞毒蛾幼虫营养物质含量、抑制抗氧化酶活性、损伤中肠组织,从而抑制舞毒蛾幼虫的生长发育,产生毒性。

In order to explore the insecticidal activity and the physiological and biochemical effects ofα−terthienyl(α−T)on the third instar larvae of Lymantria dispar,the toxicity ofα−T treatment on the third instar larvae of L.dispar and its effects on larval growth and development,nutrient contents,antioxidant enzyme activity,and midgut tissue were determined by the feed mixing method,spectrophotometry and HE staining method.The results showed thatα−T had good insecticidal activity against the third instar larvae of L.dispar 72 h after treatment,and the sublethal concentration(LC20)and median lethal concentration(LC_(50))were 20.37,178.13μg/mL,respectively.Treatment ofα−T with LC20 and LC_(50)concentrations for 72 h significantly decreased the body mass gain of the third instar larvae.The contents of soluble protein,carbohydrate,trehalose and lipids in the body were decreased.LC_(50)concentration ofα−T significantly inhibited the activities of catalase(CAT),superoxide dismutase(SOD)and peroxidase(POD)of the midgut of L.dispar larvae,and damaged the midgut tissue of larvae,resulting in significant pathological changes.α−T can inhibit the growth and development of L.dispar larvae by reducing the content of nutrients,inhibiting the activity of antioxidant enzymes,and damaging midgut tissue,thus producing toxicity.