哈茨木霉重组株L-15与野生株LTR-2贮存稳定性及生防活性研究

陈凯　李纪顺　王贻莲　魏艳丽　扈进冬　杨合同

摘要 為比较哈茨木霉重组株L-15与野生株LTR-2在贮存稳定性及生防活性方面的差异，采用平板菌落计数法检测木霉可湿性粉剂中分生孢子的存活率，测定菌株的生物学特性，并在温室条件下评价制剂对番茄立枯病的防治效果。结果表明，分生孢子存活率达80.0%时，在5℃和室温（2℃～36℃）下，L-15可湿性粉剂的货架期分别为24个月和9个月，显著高于LTR-2可湿性粉剂的12个月和6个月。L-15的潮霉素抗性在贮存后稳定遗传，其β-1， 4-葡聚糖酶水解活性、几丁质酶水解活性及平板拮抗活性较LTR-2明显提高。5℃贮存60月后，L-15可湿性粉剂10×和100×稀释处理对番茄立枯病的温室防治效果分别达89.27%和86.52%，与LTR-2处理间存在极显著性差异（P<0.01）。重组株L-15的货架期和生防活性较野生株LTR-2明显提高，在生物防治领域具有潜在应用价值。

关键词 哈茨木霉重组株L-15; 哈茨木霉野生株LTR-2; 可湿性粉剂; 货架期; 番茄立枯病; 防治效果

中图分类号：

S 476

文献标识码： A

DOI： 10.16688/j.zwbh.2019223

Storage stability and biocontrol efficiency of Trichoderma harzianum recombinant strain L-15 and wild strain LTR-2

CHEN Kai， LI Jishun*， WANG Yilian， WEI Yanli， HU Jindong， YANG Hetong

（Institute of Ecology， Qilu University of Technology （Shandong Academy of Sciences），

Shandong Provincial Key Laboratory of Applied Microbiology， Jinan 250103， China）

Abstract

To compare storage stability and biocontrol efficiency between Trichoderma harzianum recombinant strain L-15 and wild strain LTR-2， the conidiospore survival rate of wettable powder during storage period was determined by using plate colony counting method; biological characteristics of both strains were investigated， and the biocontrol efficiency of wettable powder against tomato Rizoctonia rot was evaluated under greenhouse conditions. The results demonstrated that， when the survival rate of conidiospores was maintained at 80.0%， the shelf life of L-15 wettable powder reached 24 and 9 months at 5℃ or room temperature （2℃-36℃）， respectively， which were significantly higher than those of LTR-2 wettable powder （12 and 6 months， respectively）. The hydrolytic activity of β-1，4-glucanase and chitinase in L-15 and its antagonistic activity on plate were obviously enhanced compared to LTR-2， and the introduced hygromycin resistance of L-15 was also stably inherited over storage period. Under greenhouse conditions， the biocontrol efficiencies against tomato Rizoctonia rot of 10 and 100-times dilution of L-15 wettable powder after 60 months at 5℃ were 89.27% and 86.52%， respectively， which were significantly different from LTR-2 wettable powder （P<0.01）. In summary， T.harzianum recombinant strain L-15 had an improved storage stability and biocontrol efficiency compared with wild strain LTR-2 and thus has a potential for biocontrol application.

Key words

Trichoderma harzianum recombinant strain L-15; Trichoderma harzianum wild strain LTR-2; wettable powder; shelf life; tomato Rizoctonia rot; biocontrol efficiency

木霉Trichoderma spp.是自然界广泛分布的生防真菌，自1932年Weindling[1]发现木霉的拮抗作用后，国内外专家、学者在木霉生防和应用方面做了大量工作，表明木霉具有多种生防机制：可在多种逆境下生存和定殖、有效利用环境中的营养物质、抑制植物病害发生、促进植物生长和诱导植物产生系统抗性[2-4]。木霉至少对18个属20余种病原真菌和多种病原细菌有拮抗作用，目前国际上有60多个国家使用100多种含有木霉成分的生物制剂产品[5]。

虽然自1960年木霉的生物防治功能被世界关注，但其商品化进程仍存在诸多问题：主要是缺乏合适的剂型，田间应用效果不理想以及制剂保质期短[6]。……