Abstract Abstract: With the increasing of widely polluted environmental concerns and health risks associated with the use of synthetic chemical insecticides, research and development of mycoinsecticide have been paid much attention to. However, there are some barriers to exploit entomopathogenic fungi further because of their poor performance in field. In order to widen the acceptance of mycoinsecticide products in market, the molecular biology basis of fungal pathogenesis in insect should be elucidated to identify important virulent genes, which could be then used to improve the strain performance by genetic engineering. In this paper, molecular basis of appresorium formation, cuticle degrading and the role of toxins in fungal pathogenesis in insect were introduced. Meanwhile, the gene transferring methods and its usage in strain improvement of entomopathogenic fungi were also summarized.
