李玉洋+辛寒晓+范学明+刘丽英+孙中涛

摘要：采用平板稀释法从棉花根际土壤中分离获得菌株，以尖孢镰刀菌为指示菌采用平板对峙法筛选拮抗菌，通过形态特征、生理生化特征、16S rRNA序列分析对筛选出的拮抗菌进行鉴定，采用平板对峙法研究其抗菌谱，研究其粗提液对温度、pH值和蛋白酶的拮抗稳定性，通过种子萌发及盆栽试验探究其对棉花枯萎病的防治效果。结果表明，分离获得一株对尖孢镰刀菌拮抗作用较强的菌株SN06，经鉴定为解淀粉芽孢杆菌；菌株SN06抗菌谱广，对多种病原真菌均有一定拮抗作用，且其拮抗作用具有较好的热稳定性、酸碱稳定性与蛋白酶稳定性；接种解淀粉芽孢杆菌SN06可显著降低枯萎病的发病指数，平均防效高达65.19%。解淀粉芽孢杆菌SN06在棉花枯萎病的生物防治方面具有一定的应用价值。

关键词：解淀粉芽孢杆菌；棉花枯萎病；尖孢镰刀菌；生物防治

中图分类号：S435.621文献标识号：A文章编号：1001-4942（2017）03-0117-06

AbstractThe strains were isolated from the rhizosphere soil of cotton by agar plate dilution method. Taking Fusarium oxysporum as the indicator strain， the antagonistic strain was selected by plate confrontation method. Then the antagonistic strain was identified by morphological， physiological and biochemical characteristics and 16S rRNA sequence analysis. The antibacterial spectrum was studied by the plate dilution method. The antagonism stability to temperature， pH value and protease was verified. The control effect on cotton Fusarium wilt was explored by seed germination and pot experiments. The results showed that strain SN06 exhibited an stronger antagonistic effect on Fusarium oxysporum. It was identified as Bacillus amyloliquefaciens. Strain SN06 could inhibit the growth of a variety of pathogens and had a broad antimicrobial spectrum. The strain had good antagonism stability to temperature， pH value and protease. Bacillus amyloliquefaciens SN06 could significantly reduce the disease index of cotton Fusarium wilt with the average control efficiency of 65.19%. Bacillus amyloliquefaciens SN06 had certain application value in the biological control of cotton Fusarium wilt.

KeywordsBacillus amyloliquefaciens； Cotton Fusarium wilt； Fusarium oxysporum； Biological control

棉花枯萎病是由尖孢鐮刀菌（Fusarium oxysporum）引起的真菌性病害，在世界各地普遍发生，严重危害棉花生产[1]。该病的致病机制是病原菌侵染棉花维管束等部位，堵塞导管，阻滞水分和养分运输，并产生毒素，影响棉花的新陈代谢，导致死苗、枯叶、落蕾、减产、纤维品质劣变等危害[2]。 目前，棉花枯萎病的防治以化学防治为主，常用药物主要是多菌灵、甲基托布津、百菌清、克黄枯等。化学防治不仅污染环境、危害人畜安全，而且还会使病原菌产生抗药性，降低防治效果[3]。……