Toxic and biochemical effects for certain natural compounds on the peach fruit fly, Bactrocera zonata (Diptera, Tephritidae)

Abstract

The Peach Fruit Fly (PFF), Bactrocera zonata (Saunders) is a serious pest of horticulture of crops in Egypt. The present study aimed to evaluate toxicity of the biopolymer Chitosan (Chitosanl) and its derivatives, viz., Chitosan2 (N-(2-nitrobenzyl)), Chitosan3 (N-(2-chloro, 6-fluorobenzyl)), Chitosan4 (N-(4-propylbenzyl)), Chitosan5 (N-(3,4-methelynedioxybenzyl)) as well as the bio-pesticide, Bio-fly under laboratory conditions. Also, the effect of the tested compounds on AChE and ATPase activities of both male and female flies of the PFF was assessed. Results showed that Bio-fly was the most toxic compound against both female and male flies of PFF (LC50 = 2408 and 2049 and 1333 and 1145 mg L-1 after 24 and 48 h of treatment, respectively). Among Chitosans, Chitosan2 and Chitosan4 were the most potent compounds against female and male flies after 24 and 48 h, respectively. The respective LC50 values were 4993 and 4817 and 6115 and 51775 mg L-1. AChE and ATPase activities were significantly reduced whether for female or male flies at 48 h post-treatment. Bio-fly exhibited the highest inhibition of AChE activity, whereas Chitosans gave the highest inhibition of ATPase activity. Chitosan2 and Chitosan4 could be incorporated in the integrated management programs of the PFF.