Insecticidal activity of N,S-acetal compounds under the life cycle of Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Abstract

The need for new technologies and effective products for the control of Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae) motivated several research groups around the world to describe new synthetic protocols effectively in insect control. The objective of this research was to determine the insecticidal activity of N,S-acetal compounds synthesized using Pig Pancreas Lipase (PPL) as a biocatalyst under the life cycle of P. xylostella. N,S-acetal compounds with different groups were synthesized, being methyl grouping (TB1), fluor grouping (TB2), methoxy grouping (TB3) and hydro grouping (TB4) and evaluated on P. xylostella life cycle. The larvae that fed on the TB3 compound presented approximately 5 days of life being the shortest period among the treatments performed, while the TB4 treatment was the longest period. In relation to larval survival and pupal duration, a reduction was observed in all TB treatments.  Pupal survival decreased in TB1 and TB3. The number of couples trained for the treatments was variable, and five couples were formed for water, TB2 and TB4. TB1 and TB3 treatments were 2 and 4 couples, respectively. No difference was observed between treatments for the number of eggs produced, but there was a marked reduction in viability in TB3 and TB4, causing a reduction in the formation of new larvae. Further studies should be conducted to evaluate their toxicity over time.