杂草致病菌株GD-0221的分离、鉴定与除草潜力

为明确杂草致病菌株GD-0221的除草活性与作物安全性,利用组织分离法从患病甘草(Glycyrrhiza uralensis)根部分离获得杂草致病菌株GD-0221,通过形态学和分子生物学相结合确定该菌株的分类地位,利用菌饼接种法研究该菌株对5种阔叶杂草离体叶片的致病性,用发酵液喷雾接种法研究其对5种阔叶杂草的盆栽致病性和对青海主栽作物的安全性。根据菌株形态和DNA序列分析结果,将该菌株鉴定为尖孢镰刀菌(Fusarium oxysporum)。该菌株对5种阔叶杂草密花香薷(Elsholtzia densa)、藜(Chenopodium album)、冬葵(Malva verticillata)、酸模叶蓼(Polygonum lapathifolium)、萹蓄(Polygonum aviculare)均具有致病性,活体接种试验中杂草发病率为33.33%~100.00%,对密花香薷的致病效果最突出。作物安全性方面,该菌株对青稞(Hordeum vulgare)、小麦(Triticum aestivum)表现安全,而对油菜(Brassica campestr)、蚕豆(Vicia faba)和豌豆(Pisum sativum)表现不安全。GD-0221菌株具有开发成为禾本科作物田防除阔叶杂草微生物除草剂的潜力。

Isolation,identification and herbicidal potential of weed pathogenic strain GD-0221

In order to clarify the herbicidal activity and crop safety of the weed pathogenic strain GD-0221, weed pathogenic strain GD-0221 was isolated from the root of diseased Glycyrrhiza uralensis by tissue isolation method. The taxonomic status of this strain was determined by morphological and molecular identification. The pathogenicity of the strain to the isolated leaves of five broadleaf weeds was determined by cake inoculation in vitro. The broth inoculation method was used to determine the pathogenicity to the five broadleaf weeds and the safety of the main crops in Qinghai in vivo. The strain was identified as Fusarium oxysporum by morphological and DNA sequence analysis, and it was pathogenic to five broadleaf weeds Elsholtzia densa, Chenopodium album, Malva verticillata, Polygonum lapathifolium and Polygonum aviculare. In vivo inoculation test result showed that pathogenicity rate of weeds was 33.33%-100.00%, it had the most prominent pathogenic effect on Elsholtzia densa. In terms of crop safety, the strain was safe to Hordeum vulgare, Triticum aestivum, but not safe to Brassica campestr, Vicia faba and Pisum sativum. Strain GD-0221 had the potential to be developed as a microbial herbicide against broadleaf weeds in gramineous crops.