影响杉木种子园良种产量的主要害虫及综合治理对策

在福建省洋口林场杉木种子园中常见的害虫有２６种，隶属７目２０科。其中杉木球果麦蛾、杉木扁长蝽和杉梢小卷蛾是影响良种产量的主要害虫。杉木球果麦蛾是中国新记录种，以幼虫危害球果的苞鳞、果轴及种子，使球果变色、干枯。杉木扁长蝽的危害及炭疽菌和散斑壳菌的侵染导致球果变色。１０月受害果率达３７．２％。测定结果表明，球果虫害及变色明显影响每百球果的鲜果重、种子重、千粒重及出籽率（平均下降２６．９％—７３．７％），但对种子的发芽率及涩籽率无显著影响，并提出以摘尽球果为主的综合治理措施。

Main Injurious Insects Affecting the Fine Variety Yield or Chinese Flr Seed Orchards and Their Comprehensive Harnessing Countermeasures

In Chinese fir(Cunninghamia lanceoiata)seed orchards on Yangkou Forest Farm of Fujian Province there are 26 species of common injurious insects subordinate to 7 orders 20 fami-lies. of which Dichomoris sp.Sinorsillus piliforus and Polychrosis cunninghamiacola are the main injurious inxects affecting fine variety yield. Dichomoris sp.is a new record species in China whose larvae harm the bract,cales,fruit axes and seeds of cones to make cones change their colour and dry. The harm of S. piliforus and the infection of Gloosporium sp. and Lophodermium sp. cause cones to change their colour, The affected cone rate reaches 37.2%in October. Determination re- sults demonstrate that the cone insect harm and cone colour change evldently influence the fresh cone weight.seed welght. thousand-seed weight and seed-producing rate(reducing 26.9-73.7% on the average) per hundred cones,but have no significant effect on seed germination rate and un-developed seed rate. Some comprehensive harnessing measures taking picking all cones as the dom-inant factor are put forward.