产β-1,3-葡聚糖酶植物内生放线菌的筛选及抑菌活性研究

The Screen of Plant Endophytic Actinomycetes Producing β-1,3-Glucanase and Antifungal Activity of β-1,3-Glucanase

本研究采用透明圈法,对217株植物内生放线菌产β-1,3-葡聚糖酶进行了检测,结果表明:45.6%的菌株能够产生β-1,3-葡聚糖酶,黄瓜内生放线菌中的产酶菌株最多为38个;不同植物来源的内生放线菌中具有产β-1,3-葡聚糖酶能力的菌株比例不同,其中黄精中的产酶菌株比例最高,达到88.9%。产酶菌株粗酶液对油菜菌核病菌的抑菌活性测定结果发现,36个产酶菌株的粗酶液表现出不同程度的抑制作用,占总产酶菌株的36.4%,其中菌株gCLA4的粗酶液能够完全抑制病菌菌丝生长。对gCLA4菌株产酶条件的研究发现,培养液中茯苓粉的量为0.2%,氮源为蛋白胨,初始pH在7～8之间,且培养时间为5d时,培养液中β-1,3-葡聚糖酶活较高且抑菌活性较强。gCLA4菌株的粗酶液对13种常见植物病原菌菌丝生长均有一定的抑制效果,其中对苹果轮纹病菌的抑制作用最强。

Using of clearing zones on pachyman agar medium, there are 217 plant endophytic actinomycetes, producing β-1,3-glucanase were screened. 45.6% of the strains produced β-1,3-glucanase, in which the strains from cucumber are up to 38. The percentages of endophytic actinomycetes from different hosts produceing β-1,3-glucanases were different. The percentage of the strains in Rhizoma Polygonatum produced B-1,3-glucanases is the highest, up to 88.9%. The Inhibited effects of plant endophytic actinomycetes which produced extracellular β-1,3-glucanases on mycelium growth of Sclerotinia sclerotiorum were detected in vitro. Cucumber endophytic actinomycete gCLA4 strain was screened out from 99 isolates, which can strongly inhibit the growth of S. sclerotiorum. The optimal β-1,3-glucanases fermentation conditions of strain gCLA4 were investigated, they were pachyman 0.2%, peptone as nitrogen, pH 7-8 for 5 days. The β-1,3-glucanases of strain gCLA4 had some inhibiting efficiency on 13 plant pathogens, in which inhibiting efficiency to Botryosphaeria dothidea was the strongest.