浙江省红麻立枯病菌的生理特性与药剂防治研究

Physiological Characters and Pestcide Control of Rhizcotonia Fungus on Kenaf in Zhe jiang Province:

立枯病是浙江省红麻上的一种重要病害。病原菌经鉴定为多核丝核菌 Rhizoctonia solamiKuhn。菌丝融合群(hyphal anastomosis group)的初步研究表明,5个主产麻区的分离物均匀AG-4,但上虞百官和海宁长安的分离物则有属于 AG-I 的。不同地区分离物的致病力及抗药性均有所差异;对温度、酸碱度、碳源、氮源、矿质营养的反应也不完全一致,但适宜的温度一般为28～32℃,pH 为6.4～7.5,碳源为蔗糖或乳糖、莆萄糖,氮源为胨或酵母膏,矿质营养为硝酸钾。不同品种(系)间的抗病性差异不显著,但出苗率有高低。据大田药剂防治试验结果,广谱增产菌的防效较好,且有促进麻株生长的作用。

Seedling blight has caused great damage in kenaf production in Zhejiang province,which is induced by the strains or anastomosis group of Rhizcotonia solani K(?)hn.The study of hyphal anastomosis showed that the isolates from the 5 kenaf growing regions belonged to AG-4 and that the isolates from Shangyu and Haining belonged to AG-1.The results indicated that the phathogenicity to kenaf seedlings and the resistance to some fungicides of the isolates obtained from different areas varied in their responce to the temperature,pH,carbon and N sourees as well as mineral nutrition substances.The temperature at 28-32℃ with pH of.6.4-7.5 was optimum for mycelial growth and sclerotial formation.Lactose was the most suitable carbon source for the growth of the isolates from Hangzhou,while sucrose to be the best for those from Yuhang and Haining. Peptone was used as the best nitrogen source and potasium nitrate the best mineral source.Field test showd that “Zengchangjun” gave a beeter control of the disease and encouraged the growth of plants.