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[目的]云南松Pinus yunnanensis Faranch是我国西南地区的重要造林绿化树种.近年来,云南省祥云县云南松林受到云南切梢小蠹Tomicus yunnanensis Kirkendall&Faccoli和横坑切梢小蠹Tomicus minor Hartig的共同危害.本文对两种害虫在蛀梢期的危害特性和空间分布进行了研究,以期为切梢小蠹的发生监测及防治提供依据.[方法]利用地统计学方法分析不同受害程度云南松林内两种切梢小蠹成虫蛀梢期的空间分布特性.[结果]受害程度不同的云南松林内两种切梢小蠹的危害差异显著,轻度受害林分内受害梢率为11.38％,中度受害林分内受害梢率为36.56％,而重度受害林分则达到59.7％.分析全方向的变异函数曲线图得知,蛀梢期两种切梢小蠹在不同受害云南松林中均呈聚集分布.其中,两种切梢小蠹在不同受害林分中空间依赖范围依次是:轻度受害林分>中度受害林分>重度受害林分,而局部空间连续性依次是:轻度受害林分>中度受害林分>重度受害林分.[结论]云南松林两种切梢小蠹成虫在蛀梢期的空间分布格局为聚集分布,明确两者在该时期存在聚集危害的特性,导致云南松因树梢受到聚集危害变为衰落木,从而有利于成虫蛀干危害和繁殖.本文为探究两种切梢小蠹在云南松林中的危害机制提供理论基础,也为虫害监测及防治提供参考与技术支持.“,”[Objectives] Pinus yunnanensis, which is generally regarded as a key species for the conservation of soil and water in southwest China, is heavily damaged by Tomicus yunnanensis and Tomicus minor in pine forests in Xiangyun county, Yunnan province. The characteristic damage caused by these pests during the shoot feeding period was studied in order to provide guidance and suggestions for their monitoring and prevention. [Methods] The spatial distribution of T. yunnanensis and T. minor were analyzed using geostatistical methods in three forests with different levels of damage. [Results] Damage levels caused by these species differed significantly among the three forests; only 11.38％ of shoots were damaged in lightly infested forest, 36.56％ of shoots were damaged in moderately infested forest, and 59.70％ of shoots were damaged in severely infested forest. An isotropic variogram indicated that T. yunnanensis and T. minor have an aggregated distribution in the three forests. The level of spatial dependence in the three forests could be ranked as follows: lightly infested forest > moderately infested forest>severely infested forest, and the intensity of local spatial continuity could be ranked as follows: lightly infested forest > moderately infested forest> severely infested forest. [Conclusion] Both T. yunnanensis and T. minor have aggregated distributions during the shoot feeding period. The damage to shoots caused by these aggregations can weaken Yunnan pine making it more conducive for adults to bore into the trunk and to reproduce. This study contributes to understanding the mechanism through which T. yunnanensis and T. minor damage pine trees, and provides technical guidance for their monitoring and control.