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该文系统地报道了日本松干蚧不同虫口密度等级造成的油松平均每公顷材积损失量 ,以及利用氧化乐果打孔注药法防治日本松干蚧后各虫口密度等级油松平均每公顷挽回的材积损失。通过日本松干蚧各虫口密度等级造成的经济损失与防治费用之间得失关系的分析与比较 ,得出了日本松干蚧的防治指标
This paper systematically reports the average loss per hectare of Pinus tabulaeformis from different density stages of Pinus koraiensis and the loss of volume per hectare of Pinus tabulaeformis after controlling the population of Pinus sylvestris with omethoate . Through the analysis and comparison of the relationship between the economic loss and the cost of prevention and control caused by the population density of Japanese pine scale, we got the control index