Study on Histopathological Changes of Laphygma exigua (Hubner) Infected by Beauveria bassiana and Metarhizium anisopliae

Laphygma exigua Hubner was infected by two isolates of Metarhizium anisopliae and two isolates of Beauveria bassiana.There were some changes in color and morphology on the Laphygma exigua Hubner.The result of Paraffin sections showed that the invasion process by Beauveria bassiana were similar by Metarhizium anisopliae.But the invasion speed was different.The invasion speed of Metarhizium ansopliae was faster than Beauveria bassiana..The spore in the intestine was not bourgeon and the organization of Laphygma exigua Hubner was not change at 24h.After 48h,the spore was bourgeon on the cuticular.By 72h,the hypha could be observed in the blood and began to reproduced in hemocoele.And then,the fattiness,muscle tissue and alimentary tract carryeg on a series of pathological changes.The hypha emerged through the cuticle and formed hyphal layer on the surface of the dead insect 120h postinoculation.The hypha emerged through the cuticle when Laphygma exigua Hubner was infected by Metarhizium anisopliae 060 at 72h By 96h,the organization of Laphygma exigua Hubner by Metarhizium anisopliae 086 was destroyed entirely.