Seletividade fisiológica de clorantraniliprole ao parasitoide Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae)

Abstract

Chlorantraniliprole is an anthranilic diamide recommended to control the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae).Therefore we investigated its effects on Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae), a parasitoid of DBM. We used a resistant DBM population to chlorantraniliprole and values of LC1 (0.067mg/L) and LC50 (46.1mg/L) of the insecticide. Parasitoid exposure was for two generations: i) residual; ii) ingestion; iii) topical (treated parasitoid pupae); iv) parasitism on DBM larvae fed treated leaves; v) parasitism on DBM larvae treated topically. We measured parasitoid survival for treatments i-iii, whereas for treatments iv and v, we recorded parasitism and emergence rates. Results showed that there was no difference in adult survival after direct exposure to the LC1, LC50 and control by ingestion and residual with around 95% survival, and for pupa topical application was around 34% of emerged adults (P > 0.05). In the first generation via treatment iv, parasitism rate was 63.5% and parasitoid emergence was about 71%. For the second generation, an average parasitism rate of 64.7% and parasitoid emergence of 68,7% was obtained. In exposure via treatment v, parasitism rate was about 61% and parasitoid emergence was about 68%, regardless of insecticide concentration. Similarly, in the second generation, parasitism rate was about 70,5% and 60.7% for emergence of adult parasitoids. Therefore, results show that chlorantraniliprole had low impact on C. plutellae, and in areas where DBM susceptible populations need to be controlled, chlorantraniliprole could be used in combination with biological control to manage the population of this pest.