Open AccessSublethal effects of imidacloprid on the performance of the bird cherry-oat aphid Rhopalosiphum padi
Author(s) -
Wenqiang Li,
Zengbin Lu,
Lili Li,
Yong Yu,
Shuanglin Dong,
Xingyuan Men,
Baohua Ye
Publication year - 2018
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0204097
Subject(s) - imidacloprid , rhopalosiphum padi , aphid , catalase , biology , toxicology , carboxylesterase , population dynamics , nymph , pest analysis , instar , aphididae , zoology , population , agronomy , horticulture , larva , antioxidant , botany , pesticide , homoptera , enzyme , fecundity , biochemistry , medicine , environmental health
The bird cherry-oat aphid, Rhopalosiphum padi (L.), is a major insect pest of cereal crops in many countries. Imidacloprid has been widely used for controlling piercing-sucking insect pests worldwide, but its sublethal effects on R . padi have not been well addressed. In this study, we investigated the sublethal effects of imidacloprid on biological parameters and five enzyme activities of R . padi . The LC 10 , LC 20 , and LC 25 of imidacloprid to adult aphids were 0.0053, 0.0329 and 0.0659 mg L -1 , respectively. These concentrations significantly decreased pre-adult survival rate, but prolonged the development duration of 1 st instar nymphs, pre-oviposition period, and adult longevity. Adult oviposition period was also extended by LC 20 . The intrinsic rate of increase ( r ), net reproductive rate ( R 0 ), and finite rate ( λ ) decreased at all three concentrations, whereas mean generation time ( T ) increased. Moreover, LC 20 and LC 25 significantly inhibited superoxide dismutase (SOD) activity, but increased catalase (CAT) activity. Acetylcholinesterase (AChE) activity also increased at LC 20 . However, cytochrome P450 enzyme and peroxidase (POD) activity did not differ between imidacloprid treatments and the control. In conclusion, the imidacloprid concentrations tested here have negative impacts on the performance of R . padi by reducing its nymphal survival, extending the development duration of some stages, decreasing the rate of population growth, and altering enzyme activities.