西葫芦根腐病菌拮抗细菌的防病促生作用

Biocontrol potential of antagonistic bacteria strains against Fusarium oxysporum and their growth-promoting effects on zucchini

【目的】获取促生的同时可抑制尖孢镰刀菌(Fusarium oxysporum)的拮抗菌并明确其防治效果。【方法】平板对峙生长法测定前期分离的19株促生菌对尖孢镰刀菌的抑制作用,温室条件下接种微生物菌剂对西葫芦根腐病的防治作用;田间条件下接种复合菌剂代替部分化肥对西葫芦生长的影响。【结果】可有效拮抗尖孢镰刀菌的菌株有9株,其中,菌株FX2的抑菌活性较好,抑制率达到66.80%。在温室盆栽中,接种微生物菌剂(LHS11+FX2)对西葫芦根腐病抑制率达到57.14%。在田间试验中,微生物菌剂配施化肥对西葫芦的生物量和根系形态影响显著,以85%化肥+复合菌剂处理效果较优,其对西葫芦成熟期的产量显著提高27.13%。【结论】复合菌剂(LHS11+FX2)对西葫芦根腐病具有较好的防治作用;85%化肥+复合菌剂对西葫芦的促生作用明显,在一定程度上节约了化肥投入成本,提高了增产效益。

[Objective] In order to assess potential of plant growth promoting rhizobacteria （PGPR） for protecting zucchini plants against Fusarium oxysporum, antifungal properties and growth-promoting effects of PGPR were evaluated. [Methods] 19 strains that acquired from preliminary studies were used to antagonize F. oxysporum in vitro based on panel confrontation. Control efficiency of microbial inoculant was measured on zucchini root rot at greenhouse experiments. Growth-promoting effect of compound inoculant instead of some chemical fertilizer was determined at field tests. [Results] There were 9 strains efficiently antagonized F. oxysporum. Among these strains, the inhibition rate of strain Fχ2 could rise up to 66.80%. In greenhouse experiments, the inhibition rate of microbial inoculant （LHSll＋Fχ2） reached 57.14%. In field experiments, microbial inoculant with different proportional chemical fertilizer had growth-promoting effect on biomass and root morphology, and the yield of 85% chemical fertilizer ＋ compound inoculant significantly increased 27.13%. [Conclusion] The compound inoculant （LHS1 I＋Fχ2） has excellent control efficiency to zucchini root rot. The growth-promoting effect of 85% chemical fertilizer ＋ compound inoculant is obvious on the growth of zucchini, and it largely saves fertilizer costs and improves production efficiency.