木荷皂甙对稻瘟病菌细胞形态及生理生化指标的影响  

Effects of saponins from Schima superba on cell morphology,physiological and biochemical indices of Magnaporthe oryzae

作　　者：易磊[1] 霍光华[1] 韩启灿[1] 叶亚建[1] 詹五根[1] 

机构地区：[1]江西农业大学生物科学与工程学院 南昌市生物资源保护和利用重点实验室,南昌330045

出　　处：《植物保护学报》2013年第5期450-456,共7页Journal of Plant Protection

基　　金：国家自然科学基金(31060250;21266010);江西省自然科学基金(20132BAB204028);江西省研究生创新专项资助项目(YC2011-S064)

摘　　要：为开发新型木荷皂甙杀稻瘟剂，分别采用菌丝生长速率法、显微观察、电导法和比色法研究木荷活性皂甙对稻瘟病菌Magnaportheoryzae（Hebert）Barr．的活性，以及对病原细胞形态及其胞外生理生化成分含量的影响。结果显示：木荷皂甙M2IGR5抗稻瘟病菌的EC50为16．41μg／mL、EC90为76．16μg／mL；其EC50和EC90处理稻瘟病菌茵丝体24h后，可导致菌丝断裂、细胞肿胀；处理去壁的原生质体2h即可导致其变型、粘连、破裂，引起病原菌菌丝细胞内含物大量渗漏；处理2h后的可溶性蛋白渗漏量和可溶性总糖分别较对照高10倍和30～60倍，且处理液的电导率升高、几丁质酶活性增强、胞壁几丁质组成成分N-乙酰葡萄糖胺脱落。研究表明，木荷皂甙抗稻瘟病菌不仅导致膜通透性增大、完整性丧失，而且还间接引起细胞壁降解，加速了稻瘟病菌细胞的凋亡。To develop a new agent against the rice blast with saponins from Schima superba Gardn et Champ, the activities of saponins from S. superba against Magnaporthe oryzae （Hebert） Barr. , their effects on cell morphology of the pathogen and content change in its extracellular physiological and bio- chemical components were observed using the mycelial growth rate method, microscopic observation, the conductance method and colorimetry, respectively. The results showed that EC50 and EC90 of saponins from S. superba against M. oryzae were 16.41 μg/mL and 76.16 μg/mL, respectively. Fracture and cell swelling of hyphae were caused by treatment with saponins from S. superba for 24 h. Variant, adhesion and crack of protoplasts were produced when treated for 2 h. There were a lot of leakage inclusions from treated hyphal cell of pathogen such as tenfold protein leakage and thirty to sixty times soluble sugar com- pared to control along with elevatory extracellular conductivity, enhanced chitinase activity and abscission of N-acetyl glucosamine from chitin on cell wall. It is concluded that the action of saponins from S. super- ba to M. oryzae not only leads to increased membrane permeability and loss of membrane integrity, but al- so increases chitinase activity, cell wall degradation, and further accelerates hvoha apoptosis of M. oryzae.

关 键 词：木荷皂甙 稻瘟病菌 菌丝体 作用方式 

分 类 号：S435.111.41[农业科学—农业昆虫与害虫防治]