我国每年森林病虫害发生面积达1.2亿亩,使林木产量减少1700万立方米,经济损失达50亿元。2000年11月20日,记者从在汉召开的全国林业杀虫微生物学术讨论会上了解到这一严峻现实。国家林业局副局长李育才在会上指出:当前我国森林病虫害非常严重,并呈加剧之势,对我国林业和生态环境建设已 In our country, the annual pest and disease occurrence area of ​​forest reaches 120 million mu, reducing the output of forest trees by 17 million cubic meters and the economic loss of 5 billion yuan. On November 20, 2000, the reporter learned from the stern national seminar on forestry insecticidal microbes held in Han China. Li Yucai, deputy director of the State Forestry Administration, pointed out at the meeting: At present, the forest pests and diseases in our country are very serious and are aggravating. For the construction of forestry and ecological environment in China