菌根真菌协同死谷芽孢杆菌抑制棉花黄萎病

利用温室盆钵实验,双接种丛枝菌根真菌(arbuscular mycorrhizal fungi, AMF)地表球囊霉(Glomus versiforme)和死谷芽孢杆菌(Bacillus vallismortis, HJ-5),研究AMF协同HJ-5控制棉花黄萎病的效果,并通过液相色谱法、馏分平板对峙法探析协同抗病的原因。结果表明:与对照相比,AMF和HJ-5在控制棉花黄萎病方面具有协同增效的作用,发病率下降50.82%,地下部干重增加125.00%,根际HJ-5数量增加23.80%。液相色谱分析表明,HJ-5分泌伊枯草菌素(iturin A)和表面活性素(surfactin)2种抗病性脂肽类物质。双接种AMF、HJ-5,棉花根际伊枯草菌素和表面活性素含量分别比HJ-5单处理增加13.38%和11.27%。接种AMF促进了植株地下部生长和HJ-5在棉花根际的定殖,并分泌更多的抗病类物质,是AMF与HJ-5协同抗棉花枯萎病的重要机理。

Synergetic inhibition against cotton Verticillium wilt disease of arbuscular mycorrhizal fungi cooperated with Bacillus vallismortis

In the present study, the cooperative effect of arbuscular mycorrhiza fungi (AMF) Glomus versiforme and Bacillus vallismortis HJ-5 against cotton Verticillium wilt disease was explored by greenhouse pot experiment, and the possible underlying mechanisms was revealed by high performance liquid chromatography (HPLC) and tablet test. As compared with control, AMF and HJ-5 showed synergistic inhibition against Verticillium wilt disease, as the disease index was reduced by 50.82%, root weight was increased by 125.00%, and the colonization of HJ-5 in rhizosphere was enhanced by 23.80%. HPLC analysis showed that HJ-5 could produce antifungal substances, i.e. iturin A and surfactin. Dual inoculation significantly increased the concentration of iturin A and surfactin in rhizosphere than single inoculation of HJ-5 by 13.38% and 11.27%, respectively. It was hypothesized that the main mechanism of synergetic inhibition was that AMF promoted cotton root growth, helped HJ-5 colonized in rhizosphere, and produce more antifungal lipopeptides.