生防長枝木霉菌培養特性及形態學與系統發育學鑒定1)

池玉杰　　　　　　　伊洪偉

(東北林業大學，哈爾濱，150040)　　　　(重慶市農業科學院果樹研究所)

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生防長枝木霉菌培養特性及形態學與系統發育學鑒定1)

池玉杰伊洪偉

(東北林業大學，哈爾濱，150040)(重慶市農業科學院果樹研究所)

采用宏觀觀察法和顯微鏡鏡檢的方法，在PDA和MEA培養基上對1株自我采集的具有生防價值的木霉菌株T05進行了培養特性和形態學研究。結果表明：該菌株在PDA平板培養基上生長較快，產分生孢子較早且多，也能產生厚垣孢子；在MEA上能產生分生孢子，但不產生厚垣孢子。該菌株產孢簇為松散羊毛狀到緊實的皰狀結構；分生孢子梗具有較簡單的分枝系統，通常呈直角的1～2次分枝，單生或有時成對。瓶梗不規則地在側面分布，時常單生，安瓿形或柱形，基部常縮縊但不明顯；分生孢子單細胞、長方形到橢圓形、綠色、光滑，大小為(2.0～3.0)μm×(2.0～6.0)μm。根據這些形態特征將菌株T05鑒定為長枝木霉(Trichodermalongibrachiatum)。在此基礎上，對T05的rDNA轉錄間區序列ITS和翻譯延伸因子基因tef1-α的第5內含子序列進行了擴增、測序。系統發育學的研究表明，該菌株的ITS序列和tef1-α的第5內含子序列與長枝木霉的多個菌株都具有最大的相似性，因此屬于長枝木霉。

長枝木霉；培養特性；形態學；rDNA的轉錄間區序列；翻譯延伸因子1-α亞基蛋白基因

We studied the cultural characteristics and morphology ofTrichodermastrain T05 on PDA and MEA media by using the method of macroscopical observation and microscopic examination. T05 grew fast on PDA plate, produced conidia early and much, and also produced chlamydospores, whereas, only produced conidia but not chlamydospores on MEA. The conidiophone tufts of T05 were from incompact floccose to compact bleb configuration. The conidiophones were with a simple branching system, usually with right-angled one to two time side branching which was single or paired. Phialides distributed irregularly on each side of the main axis, or secondary branches of conidiophores, often arising singly, ampulliform or cylindrical, usually only slightly attenuate at the base. Conidia were unicellular, oblong to narrowly ellipsoidal, green, smooth-walled, (2.0-3.0)μm×(2.0-6.0)μm. T05 was identified asT.longibrachiatumin sect.Longibrachiatumbased on its morphological characteristics. Then, ITS and partial gene sequence of translation factor 1-alpha (tef1-α) were amplified and sequenced, and aligned with the ITS andtef1-αsequences in GenBank of NCBI. The ITS andtef1-αsequences of T05 had the highest homology with many strains ofT.longibrachiatum, and T05 was also identified asT.longibrachiatumby molecular phylogenetic analysis.

木霉菌(Trichodermaspp.)是具有生物農藥和生物肥料開發價值的一類真菌，其具有生長速度快、環境友好、廣譜抗性的特點，以及對植物的促生作用。由于木霉對多種植物病害都具有良好的生物防治效果，已經成為生物防治和農林生產中廣泛應用的真菌，但是，每種木霉在生防功能與代謝產物上都不盡相同，因此，準確的分類鑒定對其在農林生產中的應用具有重要的意義?！?br>