title: Insecticide toxicity to oriental fruit fly Bactrocera dorsalis (Diptera: Tephritidae) is influenced by environmental factors.
abstract: In this study, we investigated the effects of environmental factors (temperature, dose, dietary source, and feeding density) on the insecticide tolerance of Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). The results indicated that the toxicities of trichlorphon and abamectin to B. dorsalis increased with an increase in temperature. At 15-35 degrees C, the toxicity of beta-cypermethrin decreased with an increase in temperature at low doses (0.82 and 1.86 mg/L), but was similar at a high dose (4.18 mg/L). These results demonstrated that the temperature coefficient of beta-cypermethrin was related to both temperature and dosage. The insecticide sensitivity of B. dorsalis reared on different dietary sources was significantly different. Trichlorphon sensitivity of B. dorsalis fed on banana was the highest with an LC50 of 1.61 mg/L, followed by on apple, carambola, semiartificial diet, pear, mango, guava, orange, and papaya. With an increasing feeding density, the sensitivity of B. dorsalis adults to trichlorphon increased, while the sensitivities of B. dorsalis adults to abamectin and beta-cypermethrin decreased. The differences between LC50 values of insects reared at densities of 10 and 13 eggs/g of semiartificial diet to trichlorphon, abamectin and beta-cypermethrin were not significant. This result suggested that representative toxicity could be obtained by using adults developed at a feeding density between 10-13 eggs/g of semiartificial diet. Adult body weight was positively correlated with the LC50 value of trichlorphon, but was negatively correlated with the toxicities of abamectin and beta-cypermethrin. These results suggested that the effects of adult body weight on the toxicity of insecticides were different among different chemicals.
authors: Laboratory of Insect Ecology, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510640, China.
authors: Yuying
authors: Y
authors: Lin
authors: Tao
authors: T
authors: Jin
authors: Ling
authors: L
authors: Zeng
authors: Yongyue
authors: Y
authors: Lu
mesh_terms: D000818:Animals; D004032:Diet; D005638:Fruit; D060434:Herbivory; D007306:Insecticides / Q000008:administration & dosage*; D007928:Lethal Dose 50; D011156:Population Density; D013696:Temperature; D033621:Tephritidae
chemical_list: D007306:Insecticides