Toxicological and biochemical studies of lufenuron, chlorfluazuron and chromafenozide against Pectinophora gossypiella (Saunders)

Abstract

In the present study, one day old eggs laboratory colony of Pectinophora gossypiella, were treated with estimated LC50 values of lufenuron 5%, chlorfluazuron 5% and chromafenozide 80% (3.471, 4.189 and 122.703 ppm respectively), to study their effects on percentage of hatchability and duration of subsequent larval, pupal, immature stages and longevity, fecundity and fertility of resulted adults. The obtained results clear that the percentage of hatchability of treated eggs were 49.6, 51.0 and 53.0 for the three tested compounds, respectively oppose to 97% in untreated control. The incubation period of the hatched eggs was 6.5, 4.7, 6.2 and 3.2 days at three (IGRS) and control, respectively. Also, the treatments affected the subsequent stages it caused significant effects on larval and pupal duration, weight and malformations. On the other hand, the adult stage resulted from treated eggs was highly affected by the three (IGRS). All the compounds especially chlorfluazuron 5% caused increasing in adult longevity and reduced the respective fecundity and fertility compared to control. The biochemical effects of the tested insect growth regulators as chitin synthesis inhibitor (CSI) against larvae resulted from (treated one-day old eggs) was studied. The obtained results indicated that the tested IGRS reduced the glucose, protein and carbohydrate contents. Also, the tested IGRSelicited inhibitory effect on alanine amino transferase (ALT) and aspirate amino transferase (AST).