【摘要】 1999—2002年,在浙江省南瓜上分离到76个疫病菌分离物,取典型的2个分离物作为供试菌株,根据对南瓜疫病的症状,疫病菌分离物的孢子囊、有性器官及菌落形态等特征的观察,以及生物学特性研究表明,孢囊梗不规则分枝,孢子囊顶生,近球形至不规则形,有明显的乳突,有的孢子囊则不止一个乳突,孢子囊成熟后易脱落,并带有长的孢囊柄,在水中极易释放出游动孢子。异宗配合,藏卵器球形,壁薄而平滑,柄多为棍棒形;雄器围生,卵孢子球形,黄褐色,壁厚而平滑,不满器,直径为16～26μm。该菌最适生长温度为25～30℃,最高生长温度大于35℃。该菌能利用淀粉及硝态氮,对孔雀石绿具有一定耐性,不产生厚垣孢子,人工接种能侵染番茄、辣椒、茄子、黄瓜、长瓜、南瓜等13种寄主植物。因此,将浙江南瓜疫病病原菌鉴定为PhytophthoracapsiciLeonian。更多还原

【Abstract】 Seventysix isolates of Phytophthora were isolated from diseased pumpkin in Zhejiang during 1999-2002. Comparative studies on morphological,cultural,physiological characters,pathogenicity and host range of the two of them were made. The sporangia vary in size, length/breadth 1.38-2.28,usually with single papilla, long sporangiophore, no chlamydospores produced. Heterothallic, oogonia spherical, smooth, 20.0-31.0 μm in diameter; Oospores spherical ,yellowbrown colour, 16-26 μm in diameter.The optimal temperature of the fungus for growth is 25.0-30.0℃,with high limitation >35℃,this fungus can utilize starch and NO-3-nitrogen.This fungus has a rather wide host range including 10 species(cucumber,pumpkin,calabash gourd,watermelon,muskmelon, tomato,eggplant,potato, Chinese waxgourdpeper).By comparing with the properties of various Phytophthora species, all the two isolates could be indentified as Phytophthora casici Leonian.更多还原