ETUDE DE L’EFFET DE DEUX CHAMPIGNONS ENTOMOPATHOGENES Beauveria bassiana et Metarhizium anisopliae var acridum SUR LE COMPORTEMENT ALIMENTAIRE DE Schistocerca gregaria

Abstract

In this study we showed that the two entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae var acridum affected the weight change of 5th nymphal instar of Schistocerca gregaria (treatment by ingestion). Examination of these results also shows that the average weight gain after 9 days of treatment in nymphal of untreated batch is 0.4230 g. It is 0.159 g for those treated with B. bassiana. Against by larvae treated with M. anisopliae their weight gain is very limited, it is 0.011 g. On the initial consumption of 5th nymphal instar of S. gregaria, it starts at the first day with 0.716±0.086g for untreateds against 0.05±0.008g and 0.691±0.083g respectively in treated B. bassiana and M. anisopliae. This consumption increases and decreases over time and reaches values either above or below the initial values until reaching the final day of the ninth 0.168±0.020 g, 0.029±0.005g and 0.068±0.008 g respectively for the untreated and treated to B. bassiana and M. anisopliae. Nutritional indices of consumption and food utilization apparent digestibility (CUDa), efficiency of conversion of digested food into body matter (ECD) and efficiency of conversion of ingested food in body (CIS) are also shown been affected by the treatment with two fungi.