摘要
西瓜枯萎病是由尖孢镰刀菌西瓜专化型(Fusarium oxysporum f.sp.niveum)引起的一种土传维管束病害,是西瓜(Citrullus lanatus)的主要病害之一。为筛选高效防治西瓜枯萎病的拮抗细菌,采用稀释涂布法和平板对峙法从对节白蜡(Fraxinus hupehensis)的根部及根际分离和筛选西瓜枯萎病菌的拮抗菌株,并测定其抑菌谱、生防特性以及盆栽防效,通过形态特征和16S rDNA序列对其进行鉴定。结果共筛选得到有效菌株50株,其中YZU-S7、YZU-S149和YZU-S146这3株细菌拮抗效果较强,对西瓜枯萎病的抑菌率分别为68.90%、73.51%和75.34%,均具有广谱的抑菌作用和产纤维素酶、蛋白酶及嗜铁素的能力,对水稻纹枯病菌、小麦赤霉病菌、玉米茎基腐病菌、马铃薯晚疫病菌具有良好的抑菌效果。用菌株YZU-S7、YZU-S149和YZU-S146的发酵液灌根接种西瓜植株,其中YZU-S149对西瓜枯萎病的防治效果最为显著,其第3次灌根后18d时西瓜植株的病情指数为17.09,而对照植株的病情指数为70.83,其防效达到75.87%。经形态学和16S rDNA分析,将菌株YZU-S149初步鉴定为枯草芽孢杆菌(Bacillus subtilis)。结果显示菌株YZU-S149对西瓜枯萎病具有良好的生防潜力和开发应用前景。
Watermelon Fusarium wilt,a soil-borne vascular bundle disease caused by Fusarium oxysporum f.sp.niveum,is one of the main diseases on watermelon(Citrullus lanatus).To screen antagonistic bacteria for effective control of watermelon Fusarium wilt,dilution coating method and plate confrontation method were used to isolate and screen antagonistic strains of watermelon fusarium wilt from the roots and rhizosphere of Fraxinus hupehensis.Their antifungal spectrum,biocontrol characteristics and potted plant control effect were determined.The morphological characteristics and 16S rDNA sequence were used to identify them.The results show that a total of 50 effective strains have been screened,among which YZU-S7,YZU-S149 and YZU-S146 show strong inhibitory activity against watermelon Fusarium wilt,and their inhibition rates are 68.90%,73.51%and 75.34%,respectively.They all have broad-spectrum antifungal activity against the pathogens of rice sheath blight,wheat scab,corn stalk rot and potato late blight,and have abilities to produce cellulose,protease and siderophores.Fermentation broth of the three strains YZU-S7,YZU-S149 and YZU-S146 was used to irrigate the roots of watermelon seedlings,and the control effect of YZU-S149 on watermelon wilt is the most significant.At 18 days after the third root irrigation,the disease index of watermelon seedlings is 17.09,while the disease index of control plants is 70.83,and the control efficacy reaches 75.87%.The strain YZU-S149 was preliminarily identified as Bacillus subtilis by morphological and 16S rDNA analysis.The results indicate that strain YZU-S149 has good biocontrol potential and development prospect against watermelonFusarium wilt.
作者
孙正祥
龙欣钰
孟祥佳
曹帅
毛国庆
周燚
SUN Zhengxiang;LONG Xinyu;MENG Xiangjia;CAO Shuai;MAO Guoqing;ZHOU Yi(College of Agriculture,Yangtze University,Jingzhou 434025,Hubei;Forewarning and Management of Agricultural and Forestry Pests,Hubei Engineering Technology Center(Yangtze University),Jingzhou 434025,Hubei)
出处
《长江大学学报（自然科学版）》
2021年第4期114-120,共7页
Journal of Yangtze University(Natural Science Edition)
基金
湖北省教育厅重点项目“蜡状芽孢杆菌YUPP-10抑菌活性物质的分离纯化及其分子作用机制的研究”(D20181304)
湖北省大学生创新创业训练计划项目“一株新型生防细菌S17-377抑菌活性物质的分离鉴定”(2019254)。
关键词
西瓜枯萎病
拮抗菌株
生物防治
防效
分离鉴定
watermelon Fusarium wilt
antagonistic strain
biological control
control effect
isolation and identification
