普城沙雷氏菌MM产酶条件优化及对西瓜枯萎病的防治效果  

Optimization of Enzyme Production Conditions of Serratia plymuthica MM and Its Control Effect on Watermelon Fusarium Wilt

作　　者：马金秀 张锦锋 王江来 李佳佳 李昭煜 刘璐[1] 田永强[1] MA Jinxiu;ZHANG Jinfeng;WANG Jianglai;LI Jiajia;LI Zhaoyu;LIU Lu;TIAN Yongqiang(School of Biological and Pharmaceutical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学生物与制药工程学院,兰州730070

出　　处：《西北农业学报》2022年第12期1635-1645,共11页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家自然科学基金(21967015);甘肃省重点研发计划(20YF3FA038);嘉峪关市重点研发计划(21-19)。

摘　　要：为提高普城沙雷氏菌MM几丁质酶产量,增强拮抗西瓜枯萎病病原菌的能力,通过Plackett-Burman设计和响应面法对其培养基成分进行优化,并测定优化后菌株MM发酵滤液对西瓜种子萌发及西瓜枯萎病防治效果的影响。结果显示,在初始pH 7.0、接种量3%、温度30℃、摇床转速180 r/min、培养时间72 h的基础上获得最佳产酶培养基:葡萄糖12.748 g/L,牛肉膏2.086 g/L,酵母粉3.091 g/L;优化后菌株MM几丁质酶活为0.485 U/mL,比优化前提高1.14倍,对西瓜枯萎病病原菌的抑菌率提高6.42%。菌株MM发酵滤液不同稀释倍数对西瓜种子的萌发具有促进作用,当发酵滤液稀释浓度为150倍时对种子萌发的促进作用最为显著,为98.53%。盆栽试验显示,菌株MM发酵滤液处理西瓜植株后,其株高、鲜质量、干质量分别增加78.82%、126.90%、82.00%,对西瓜枯萎病防效高达74.55%。In order to improve the chitinase production of Serratia plymuthica MM and enhance the ability to antagonize Fusarium oxysporum f.sp.niveum,the medium composition was optimized by Plackett Burman design and response surface methodology,and the effect of the optimized fermentation filtrate of strain MM on watermelon seeds germination and control of the watermelon Fusarium wilt were determined.The results showed that the best enzyme producing medium was glucose 12.748 g/L,beef extract 2.086 g/L and yeast powder 3.091 g/L on the basis of initial pH 7.0,inoculation amount 3%,temperature 30℃,shaking speed 180 r/min and fermentation time 72 h;the chitinase activity of the optimized strain MM was 0.485 U/mL,which was about 1.14 times higher than that before optimization,and the inhibition rate was increased by 6.42%.Different dilution times of the fermentation filtrate of strain MM could promote the germination of watermelon seeds,the most significant improvement reached to 98.53%when the dilution concentration of MM fermentation filtrate was 150 times;the pot experiment showed that the plant height,fresh mass and dry mass of watermelon plants treated with strain MM fermentation filtrate increased by 78.82%,126.90%and 82.00%,respectively,the control effect on watermelon Fusarium wilt was 74.55%;this study provides a theoretical basis for the production and application of chitinase of strain MM and the control of watermelon Fusarium wilt.

关 键 词：普城沙雷氏菌 几丁质酶 响应面优化 西瓜枯萎病防治 

分 类 号：Q939.95[生物学—微生物学]