【摘要】 落叶松落叶病、枯梢病、褐锈病、兴安落叶松鞘蛾、落叶松球蚜、大蚜同为落叶松冠层的主要病虫害，但各具不同的生态位．不同害虫（ 包括虫态） 、病害对落叶松冠层的作用时序均具交错出现、相互回避的现象．对生态环境亦各有不同选择，鞘蛾和球蚜大都喜于平坦、阳坡的林分，林分郁闭度０ ．８ ～０ ．５ 为宜，尤以鞘蛾更喜于林缘和林分的天窗．通过对病虫害的综合作用研究，从落叶松生长期６ 种病虫作用生命表中得知，自５ 月下旬至７ 月上旬，落叶松冠层中以害虫危害为主，自７ 月下旬病害加入，使林木受害逐渐加重．仅有３ 种害虫危害时，生命表中Ｋｘ 值为０ ．０１６ ～０ ．０１９７ ，病害加入后Ｋｘ 值增至０ ．１２４ ，９ 月７ 日Ｋｘ 值达０ ．２６ ．３ 种病害的大量失叶时间为８ 月，可连续影响３ 年生长，影响最大者为第２ 年，鞘蛾在５ 月造成大量失叶．更多还原

【Abstract】 The fungi of Mycosphaerella larici leptolepis,Botryosphaeria laricina,Triphragmiopses laricimum and insects of Coleophora dahurica,Adelges laricis,Cinara laricis are common pests on larch (Larix olgensis) . Each species possesses different ecological niche on larch crown. The effects of different insects (or developmental phases) and diseases on larch crown showed the phenomena of alternate emergence over time,inter evasion and selecting different ecological environments.The life table of 6 pests showed that the insect pests were major pests of the larch crown from late May to early July.After late July when fungi diseases invaded the needles and shoots,the larch was injured seriously.When 3 insect pests attached larch only,the Kx value in life table was 0.016～0.0197. While the diseases affected,Kx was up to 0.124,reaching 0.26 on September 7. The fungal diseases seriously defoliated larch trees in August,which could affect continuously the growth of larch for 3 years,and most seriously in second year. C.dahurica defoliated trees in May.更多还原