Biological effect for oils of tamarind seeds Tamarindus indica L. and galangal rhizomes Alpinia officinarum (Hance) in southern cowpea beetle Callosobruchus maculatus F. (Coleoptera : Bruchidae).

Abstract

Studies on the use each oils of tamarind seeds and galangal rhizomes against the southern cowpea beetle Callosobruchus maculatus F. in cowpea seeds (reddish, white, reddish-brown and black) revealed that there was significant toxic effect of all concentrations on immature stages and adult stage insect emergence. Tamarind seeds oil was more effective than galangal rhizomes oil in all treatments. The rates of productivity and first generation (F1) reduction in southern cowpea beetle for cowpea seeds for tamarind seeds oil at 2.5/20g reached 40, 30.03, 22.00 and 16.50 % , 95.08, 96.29, 96.95 and 97.00% respectively and for galangal rhizomes oil was 86.76, 79.46, 66.60 and 33.20 % and 51.64 , 61.74 , 76.91 and 69.72 % respectively at the same concentration. The developmental period was positively decreased in relation with increase of concentration of oils. All concentrations of these oils that treated cowpea seeds four didn’t affect on germinability percentages ranged 70.00-80.00% and 76.66-96.66% for tamarind seeds and galangal rhizomes oils respectively. Also significant difference found clearly in the attraction and repellency responses. The tamarind seeds oil in different concentrations showed a superior repellency effect on insect reached maximum at 2.5%, the highest average of individuals repellency reached 3.66 and 5.00 rates 36.60 and 50.00% with attractant rates 6.60 and 3.30 % as it balance rates reached -33.30 and -43.40% after15 and 30 minutes of treating, while galangal rhizomes oil showed significant attractant effect, the concentration 2.5% recorded highest rates of attractant, the average of individuals attractant reached 6.66 and 7.66% rates 66.60 and 76.60% and repellent rates 0.33 and 0.00% as it balance rates reached + 63.30 and + 68.94% after 15 and 30 minutes of treating.