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通过定时定位观察云南松松纵坑切梢小蠹危害程度与云南松经济损失之间的关系，经统计分析，确定松纵坑切梢小蠹的防治指标为：平均虫孔数０．１８９虫孔／株，林木平均枯死率０．５２％，平均株枯梢率４．７４％，有虫株率５．１４％。确定昆明地区方旺林场的经济阈值为０．２１５１虫孔／株；并制订了适合于基层林区的多个动态经济阈值。当虫孔密度达到０．３３３８×ＣＣ÷（Ｙ×ＥＣ×Ｐ），对应的林木平均枯死率为０．３８９＋０．３６６７×ＣＣ÷（Ｙ×ＥＣ×Ｐ）、平均株枯梢率为５．５３９８＋１．１３０１×ＣＣ÷（Ｙ×ＥＣ×Ｐ）、平均有虫株率为１．６３＋１４．４８２１×ＣＣ÷（Ｙ×ＥＣ×Ｐ）时，防治投入与挽回经济损失相等，应进行防治。
The relationship between the degree of damage and the economic loss of Pinus yunnanensis in Pinus yunnanensis was observed by timed positioning. The statistical analysis showed that the control indexes of Pinus sylvestris were 0.189 Holes / strains, the average mortality of trees 0.52%, the average rate of 4.74% shoot blight, the rate of 5.14% of the worm. The economic threshold of Fangwang Forest Farm in Kunming was determined to be 0.2151 insect hole per plant, and a number of dynamic economic thresholds suitable for grassland forest areas were formulated. When the wormhole density reached 0.3338 × CC × (Y × EC × P), the average mortality rate of trees was 0.389 + 0.3667 × CC × (Y × EC × P). 5398 + 1.1301 × CC ÷ (Y × EC × P), the average strain rate is 1.63 + 14.4821 × CC ÷ (Y × EC × P).