【摘要】 根据黄萎病菌在培养基上能形成微菌核的特性,寻找适于种子与土壤中黄萎病菌微菌核形成的培养基和相应的检查种籽和土壤带菌的方法。1.试验结果表明,棉籽饼粉酒精洋菜培养基(棉籽饼粉10克、95%酒精17毫升、键霉素100p.p.m.、洋菜7.5克、水1000毫升制成)对病菌形成微菌核的效果比 Nadakavakaren 介绍的培养基显著优越。即使对“退化”病菌,亦能促其迅速恢复形成大量微菌核的能力。2.应用上述棉籽饼粉酒精洋菜培养基对从辽阳、临汾和安阳各地黄萎病株上采收的种子进行分离,可得到肉眼可见的微菌核丛,而且具有典型的轮生分生孢子梗,纯化的病菌接种棉苗也表现典型症状。直接证明了这些棉籽确实带有黄萎病菌。用无病田采收的种子进行分离,无微菌核丛形成。3.用上述培养基进行土壤黄萎病菌的分离,也获得比其他培养基显著优越的结果,每皿可出现4—7个微菌核丛。其他培养基仅出现少量甚至完全不形成微菌核。4.上述种子和土壤黄萎病菌分离和检查方法,可试用于种子和土壤带菌的检查及有关种子和土壤消毒效果等的研究。更多还原

【Abstract】 The present paper deals with some experiments attempting to suggest an easier and morereliable method of isolation and identification of the Verticillium wilt organism especially forthe purpose of seeds and soil inspection.The results obtained are as follows:1.The cotton seed cake meal agar (cotton seed cake meal 10 g.,95% alcohol 17 ml.,Strep-tomycin 100 p.p.m,agar-agar 7.5 g.and water ad.1000 ml.) gave the best results,which wasremarkably superior to the Nadakavakaren’s alcohol agar and other media.By using the statedmedium,even a“degenerated strain”which has lost its ability of microsclerotia formation forseveral years again formed large amount of microsclerotia immediately.2.In isolations of the seed-borne Verticillium from the fuzzed cotton seed collected fromthe diseased plants of different localities,microsclerotial colonies were found macroscopically inthe above mentioned medium.After purification,the typical verticilliate conidiophores wereobserved.Typical symptoms on the cotton seedlings which were inoculated with the purifiedculture resulted.According to the number of the microsclerotial colonies formed,the per-centage of infected seeds was estimated to be about 5%.It was also found that both welldeveloped and under developed seeds of the same origin were equally infected by Verticillium.No microsclerotia formation was observed on seeds collected from the field free from Verticilliumin Peking by means of the same method.3.Soil collected from the infested field was also studied with the above mentioned medium.In each plate,4-7 tufts of microsclerotia were formed while in other media microsclerotia werescarcely produced.4.It is suggested that this method of isolation and identification of the seeds,as well asscil-borne Verticillium wilt organism is a more practical and reliable one.更多还原