核盘菌与灰葡萄孢菌的培养特性及对油菜致病性比较

Culture Characters of Sclerotinia scleriotiorumand Botryis cinerea as well as Their Pathogenicity to Rapeseed

通过对从中国不同地区采集到的油菜菌核盘菌(Sclerotinia sclerotiorum)和从陕西大荔采集到的灰葡萄孢菌(Botrytis cinerea)的菌核进行单菌核分离、培养、纯化,共获得22个菌株,其中核盘菌12个,灰葡萄孢10个,进一步对两种真菌的菌落扩展速度、菌落形态、菌核产量及其在PDA平板上的分布特征和各菌株对油菜致病性的强弱等进行比较研究。结果表明:在同一温度和pH下,核盘菌S的菌丝生长速度快于灰葡萄孢B;在不同培养温度或pH下,两类菌株菌落的扩展速度虽不相同,但其变化趋势却基本相同,两类菌株均在24℃和pH为5时扩展速度最快,pH为3时菌株菌丝体产量最大,在PDA平板上,菌株S和B不亲和,其分属于两个不同的亲和群,S间或B间以及各菌株自身的营养体均表现亲和;12个核盘菌株S在室内外对油菜均有较强的致病性,同时亦存在致病力的分化,其中S1的致病性强于S2,而10个灰葡萄孢菌株B在田间对油菜均不致病,仅在室内对离体叶有弱的致病性,说明灰葡萄孢目前对陕西大荔区油菜不会造成实质性的侵染与危害。

Sclerotia of Sclerotinia sclerotiorum in rapeseed collected from different regions of China and sclerotia of Botrytis cinerea from dali county of shaanxi province were isolated, cultured and puri fled to single-sclerotium. 22 strains were obtained,including 12 Sclerotinia sclerotiorurn and 10 Botryis cinerea. Then the growth speed of hyphae and the characters of colony as well as the yield of sclerotia and its distribution characters on colony and the pathogenicity of all strains to rapeseed were studied. The results indicated that the growth speed of hyphae of Sclerotinia sclerotiorum （S） was quicker than Botrytis cinerea B under the same temperature and pH;although the growth speed of hyphae was different,the trend was basically same under different temperature and pH. The growth of the two types was the quickest under 24 ℃ and pH 5, and the yield of hyphae was the highest under pH 3;in the PDA plate, S and B appeared incompatible, they belong to two groups, the vegetative between strain S and B as well as inside the same type appeared compatible; the 12 Sclerotinia sclerotiorum strains have strong pathogenicity indoor and outdoor to rapeseed and pathogenicity differentiation, a- mong them S1 was stronger then S2. The 10 Botrytis cinerea have no pathogenicity to rapeseed in thefield,only have weak pathogenicity to detached leaves in the interior. The result of the investigation in- dicated Botrytis cinerea would have no substantial infection or harm to our rapeseed at present.