, a new potential strain for controlling from China.

is one of the most serious pests of buckwheat, with its larvae mainly damaging leaves during the seedling and flowering stages. Entomogenous fungi play a crucial role as biological regulators of arthropod populations in nature. In this paper, a newly isolated strain 19GZAl-1, was identified as through the observetions of macroscopic and microscopic morphological features, and the results of rDNA- ITS sequence alignment and phylogenetic analysis. By comparing the efficacy of ten entomopathogenic fungal strains, including six strains of and four other species, against larvae, the new strain 19GZAl-1 exhibited the highest mortality rate. Mortality rates of larvae treated by spraying with the strain 19GZAl-1 increased as larval stage decreased, with first instar larvae showing the highest mortality rate of 85%. The appressorium from conidia invaded the larval body through areas with thin cuticle, such as larva pod base and internode folds, after which the hyphae grew rapidly, filling the haemocoel, and finally protruding from the integument upon melanization and decomposition of the intestinal wall cells. The results suggest that the strain 19GZAL-1 of has potential against larvae, which is significant for further study on the infection mechanism of on insects.