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雪岭云杉芽枯病是发生于乌鲁木齐市南山实习林场的一种我国新记录病害。此病在南山林场的发病率达３５．７％；从调查的树冠部位来看，上部发病率最高；从树冠方位看，东面发病率最高，北面最低。病菌以分生孢子和子囊孢子分别在云杉小枝上发病的顶芽和侧芽内越冬，病原菌可在人工培养基上生长。经鉴定，人工培养条件下的病原菌的无性态为立枯丝核菌（ＲｈｉｚｏｃｔｏｎｉａｓｏｌａｎｉＫｕｈｎ），最适生长温度为（２０±１）℃，最适光照时间为６ｈ。由病组织分离结果可知，在枯死的叶芽上还附生有交链孢（ＡｌｔｅｒｎａｔｉａＮｅｓ）、曲霉（ＡｓｐｅｒｇｉｌｕｓＭｉｃｈｗｌｉｅｘＬｉｎｋ）、小菌核菌（ＳｃｌｅｒｏｔｉｒｍＴｏｄｅｅｔＰｅｒｓｏｏｎ）３种真菌
The snowy spruce bud disease is a kind of newly recorded disease in our country which occurred in the forest farm in Nanshan, Urumqi. The disease incidence rate in Nanshan forestry field reached 35.7%. From the canopy position of investigation, the upper part incidence rate was the highest. From the canopy orientation, the highest incidence in the east and the lowest in the north. Pathogenic bacteria can grow on artificial medium with conidia and ascospores overwintering in the top bud and lateral bud, respectively, on the spruce branchlets. It was identified that under the condition of artificial cultivation, the pathogen was Rhizoctonia solani (RhioceaniasolaniKuhn). The optimum growth temperature was (20 ± 1) ℃ and the optimum illumination time was 6h. Isolation results from the diseased tissue indicate that the dead leaf buds also contain three species of fungi, Alternatia Nes, Aspergillus sichwliex Link, Sclerotire Todeet Persoon,