【摘要】 <正> 杨树肿茎溃疡病,是一种新病害,近年来在黑龙江、吉林两省普遍发生,为害多种杨树品种,其中以小×黑(Populus simonii×nigra)、小青×黑(Populus pseudosimonii×nigra)和北京杨605(Populus pakinensis-605)受害严重。由于肿茎溃疡病,会导致育苗和造林的失败,对杨树威胁很大。为确保杨树育苗和造林成果,自1982更多还原

【Abstract】 Swollen stem canker of poplars is a new disease that has not been reported at home and abroad. It distributes widely, damages badly and is a serious threat to the poplar management. It is proved that the disease is an experance of grey leaf-spot of poplar on the stem through the cross-inoculation. The pathogen of the disease is Coryneum populinum Bresad. The pathogen penetrates the host through wounds or directly through the epidermis. The incubation period of the disease is 7—10 days and the reproduction period 17—20 days. The pathogen survives through winter by means of conidia and the conidia are washed, splashed by rain and spread by winds. The conidia can germinate at 5℃—35℃ and the optimum temperature for conidia to germinate is 25℃. Conidia germinate well in the waterdrops and few would germinate when the humidity is below 41％. The optimum pH for colony to grow is pH6. Malt is the best source of carbon and alanine is the best source of nitrogen. Vitamin H and Vitamin B have great effect on the growth of colony.From late June to early July, 75％ Bravo 500×, 50％ Bovistin 600×, 65％ Dithanen 500×, and 70％ Toosin M 600× are sprayed to control the disease and the result is satisfactory.更多还原