Effect of Nimbecidine 0.03% And Bacillus thuringiensis on the second larval instar of Lemon butterfly Papilio demodocus Esper

Abstract

The experimental work was conducted during the period of February -March (2006) in the entomology laboratory of the College of Agricultural Studies Shambat, Sudan University of Science and Technology to evaluate the effect of Nimbecidine 0.03% and Bacillus thuringiensis var Kurstaki (B.T) under trade name "Agerin" against the second larval instar of lemon butterfly Papilio demodocus Esper. Results of Nimbecidine on larvae of P. demodocus were very good and caused significant mortality. The effect was dose related as mortality increased with increase in dose. On the second day there were no significant (p>0.05) difference between the recommended dose (3.6m/l) and the higher dose (4.5m/l). The mortality caused by both recommended dose (3.6m/l) and the higher dose (4.5m/l) was significantly higher than the lower dose (2.7m/l) and the control. On the third day the higher dose (4.5m/l) gave better results than the recommended dose (3.6m/l) and the lower dose (2.7m/l). Results of Bacillus thuringiensis against the second larval instars of P. demodocus showed that the doses 1.33g/l and 1.66g/l were more effective than the lower dose 0.98g/l and the control on the second day. On the third day the highest dose 1.66g/l was more effective (p<0.05) than both the recommended dose 1.33g/l and the lower dose 0.98g/l in addition to the control.

In case of the effect of the mixture of Ninbecidine and the bacteria Bacillus thuringiensis the lower doses 2.6m/l+0.98g/l gave significantly higher mortality than the control on the second and third day. The recommended dose 3.6m/l+1.33g/l gave better results than the lower dose 2.7m/l+0.98g/l and the control on the second and third days . The study showed that Nimbecidine at 4.5m/l is effective in the control of the larvae of P . demodocus. Future field trials are required to confirm these laboratory results.