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林木害虫的发生与环境因子有着密切的关系,往往由于环境因子的变化,导致病虫害的发生和消亡。为进一步探讨牡蛎介壳虫的发生与环境因子的关系,现就多伦县国营苗圃观察果做一简要介绍。一、牡蛎介壳虫的发生与降雨的关系圃内杨树防护林,多为没有出圃的苗木长成林的。林木稠密,卫生情况不良。1972年多伦地区时逢干旱,年降雨仅为260.1毫米,因而林木长势衰弱。1973年已发现有牡蛎介壳虫,1973—1979年气候正常,给牡蛎介壳虫的蔓延创造了条件,1980—1981
The occurrence of forest pests and environmental factors are closely related, often due to changes in environmental factors, leading to the occurrence and elimination of pests and diseases. In order to further explore the relationship between the occurrence of oyster scale insects and environmental factors, a brief introduction is made on the observation fruits in the state nurseries of Duolun County. First, the occurrence of oyster scale insects and the relationship between precipitation Nursery poplar shelter, mostly no nursery seedlings grow into forests. Thick trees, poor health conditions. In 1972, when the region of Duolun was wet and the annual rainfall was only 260.1 millimeters, the forest was weak. Oyster scale insects were found in 1973 and normalized from 1973 to 1979, creating conditions for the spread of oyster scale insects, 1980-1981