Some changes in color and morphology of Anoplophora glabripennis larvae were observed when infected with Metarhizium (Metsch.) Sorokin MS01. Paraffin sections show the spores of MS01 attached to the cuticle of A. glabripennis larvae at 24h post inoculation (hpi). At 36hpi, the conidium germinated and penetrated through the cuticle. After 48h of inoculation, the endocuticle was disintegrated and the germ tubes passed through the epithelial layers into the hemocoel and multiplied, and then invaded the tissues near the penetration point, such as the fat body, muscle, tracheal tissue, malpighian tubule, alimentary canal, etc. The infected larvae were dead and most tissues and organs were infected and disintegrated with the multiplication of the mycelium for 3days. The hyphae emerged through the cuticle and formed a hyphal layer on the surface of the dead insect and the conidium emerged five days after inoculation. |