核桃内生菌XHE7对病原真菌的拮抗作用及种子发芽的影响

The Antagonism of Walnut Endophyte XHE7 against Plant Pathogenic Fungi and Effect on Crop Germination

植物内生菌有广泛的生物防治及促进植物生长发育的潜力。为了明确前期分离得到的1株核桃内生细菌XHE7的生物防治潜力及对作物种子萌发的影响,通过平板对峙法测定该菌株对11种植物病原真菌的拮抗作用,此外,测定该菌株对12种作物种子的萌发以及芽和根长度的影响。结果表明,XHE7对所测试的11个菌株都表现出一定的拮抗作用,其中对草莓灰霉病菌(Botrytis cinerea)的抑制率最高,达78.1%,而对禾谷镰刀病菌(Fusarium graminearum)的拮抗作用相对较弱,其抑制率仅为36.7%。该菌株可使大豆的种子发芽率增加19.23%,而使苏丹草种子萌发率降低25.00%。此外,该菌株可促进玉米的根长和芽长分别增加81.0%和99.2%。研究结果为进一步开发该核桃内生菌的生防功能提供理论依据。

Plant endophyte has great potential in controlling plant diseases and promoting plant growth.In order to elucidate the biocontrol potential and effects of walnut endophyte XHE7 on crop seed germination, 11 plant pathogenic fungi were assayed with dual culture method on plate, as well as the germination and length of buds and radicles of the seeds of 12 crops were tested.The results indicated that XHE7 strain could antagonize all 11 tested pathogenic fungi in some degree.Among these tests, the highest inhibition rate against the strawberry grey mold pathogen Botrytis cinerea was 78.1%, while the lowest inhibition rate against Fusarium graminearum was 36.7%.The strain increased maize seed germination rate by 19.23% but decreased Sorghum sudanense seed germination rate by 25.00%. Moreover, the length of maize radicles and buds increased by 81.0% and 99.2%respectively compared with those of the control.These findings lied a strong foundation for the development of the biocontrol potential and further application of walnut endophyte XHE7.