甘草内生菌Z4菌株对灰霉病菌的作用机制初探

为探究甘草内生菌Z4 菌株的发酵上清液对灰霉病菌的抑菌机制，采用抑制菌丝生长速率法及抑制孢子萌发法，结合扫描电镜和透射电镜，观察Z4 菌株发酵上清液处理前后灰霉病菌菌丝形态结构的变化情况。采用盆栽试验测试活性物质在活体黄瓜内的传导性。通过扫描电镜、透射电镜及光镜观察发现，Z4 菌株的发酵上清液使番茄灰霉病菌菌丝扭曲变形、表面皱缩、部分菌丝断裂；细胞壁溶解破裂，细胞内液泡出现空腔；孢子萌发率低及芽管生长缓慢。盆栽黄瓜灌根和涂叶处理前后，黄瓜的病指分别由82.3 降至28.05 以及83.11 降至30.60，防治效果分别为63.12%和60.28%。表明Z4 菌株发酵上清液对灰霉病菌菌丝细胞的细胞壁具有破坏作用，且活性物质在活体黄瓜内有一定传导性。

Preliminary Investigation of Mechanism of Action of Z4 Endophytic Strain Separated from Wild Liquorice for Botrytis cirerea

The study aims to investigate the antifungal mechanism of the supernatant fermentation from Z4 strain in vitro. The action mechanism of Z4 strain was surveyed by inhibiting the mycelial growth ratio and spore germination, combining scanning electronic microscope, transmission electronic microscope and potted plant. The results indicated that the fermentation extracts exhibited antifungal activities to mycelium growth of Botrytis cinerea. The fermentation extracts could inhibit the spore germination and the bud growth of Botrytis cinerea. Also the sample had a series of marked morphological and structural alterations of the mycelium underthe light microscope and electronic microscope, such as prayer beads swollen of part of mycelium and malforming septa under scan electronic microscope, the cell wall dissolution and the cell liquid seepage under transmission electronic microscope. In addition, disease index of potted cucumber after treated by rootirrigation and spread on leaf were reduced from 82.3 to 28.05 and 83.11 to 30.60, respectively. Control efficiency of the fermentation products of Z4 strain against the Botrytis cinerea were 63.12% and 60.28%, respectively. The cytological changes above were resulted in the necrosis of mycelium cell wall. In addition, the conductivity of the sample displayed in internal of cucumber.