The toxic effect of camphor vapour against Aphis craccivora Koch (Hemiptera: Aphididae) and some of its natural enemies

Fumigant toxicity of camphor was studied against the aphid aphis craccivora koch and three associated natural enemies, i.e. coccinella undecimpunctata l., aphelinus albipodus hayat & fatima and aphidius colemani viereck. aphis craccivora was the most tolerant one compared with all tested natural enemies as the recorded lc_50 values were 12.71, 6.33, 1.16 and 0.48 mg camphor/liter space for the above mentioned insects, respectively. subjecting newly emerged adults of a. craccivora to lc_25 of camphor vapor significantly reduced female longevity from 17.6 to 6.45 days and reduced the female daily progeny from 4.44 to 1.93 nymph / female, which resulted in a reduction in productivity as finite rate of increase decreased from 1.57 to 1.14 female / female / day. aphids that survived after subjection to lc_50 were found to have significantly higher amount of acid phosphatase and g. s-transferase than non-treated aphids. inversely, survived aphids were found to have significantly less amount of β-esterases and alkaline phosphatase than nontreated aphids; while no significant difference was found in case of α-esterases. camphor fumigant can be a candidate as a control agent against a. craccivora but with restriction because of its drawbacks on natural enemies.