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松突圆蚧危害程度的划分是以2年生枝条上松针的保存率、枝梢形状和生势作为依据,用60株平均木树干解析连年生长量验证,准确率达87.73%。对惠东、深圳等6个县(市)9个调查区60块标准地的综合调查结果:危害轻度和中等的林下植物多为草本植物群丛组、桃金娘群丛,其土层松厚肥沃;危害较严重和严重的林下植物多为芒萁群丛、马唐+芒萁群丛及山的上部,其土壤酸度大、瘠薄。林分因子中,郁闭度与危害程度呈多项式二次幂关系,郁闭度0.5～0.65的危害最轻;水汽压与郁闭度也呈多项式二次幂关系,郁闭度0.5～0.6的水汽压最低。合理的修枝间伐,控制林分郁闭度在0.5～0.65之间,可提高林木的抗虫性。
Based on the preservation rate of shoots, shoot shape and emergence potential of two-year-old shoots, the degree of damage of P. crassicarpa was verified by 60 average annual tree trunks, and the accuracy rate was 87.73%. A comprehensive survey of 60 standard plots in nine survey areas including Huidong and Shenzhen in six counties (cities) showed that most of the undergrowths harbored mild and moderate were herbaceous plant group, myrtle group, soil The layer is loose and fertile. More undergrowth and serious undergrowth are Manta group, Cang Tang + Manta group and the upper part of the mountain. The soil is acid and infertile. Among the stand factors, the degree of canopy closure and the extent of the hazard showed a polynomial second power relationship. The canopy density of 0.5-0.65 was the least harmful. The vapor pressure and canopy density also showed a polynomial second power relationship with canopy closure of 0.5-0.6 The lowest vapor pressure. Reasonable pruning thinning, canopy density control between 0.5 ~ 0.65, can improve the insect resistance of trees.