Abstract:
Halo-alkali soil threatens agriculture, reducing growth and crop yield worldwide. In this study, physicochemical and molecular techniques were employed to explore the potential of halo-alkali-tolerant endophytic bacteria strains Sphingomonas sp. pp01, Bacillus sp. pp02, Pantoea sp. pp04, and Enterobacter sp. pp06 to enhance the growth of hybrid Pennisetum under varying saline conditions. The strains exhibited tolerance to high salt concentrations, alkaline pH, and high temperatures. Under controlled conditions, all four strains showed significant growth-promoting effects on hybrid Pennisetum inoculated individually or in combination. However, the effects were significantly reduced in coastal saline soil. The best growth-promoting effect was achieved under greenhouse conditions, increasing shoot fresh and dry weights of hybrid Pennisetum by up to 457.7% and 374.7%, respectively, using irrigating trials. Metagenomic sequencing analysis revealed that the diversity and composition of rhizosphere microbiota underwent significant changes after inoculation with endophytic bacteria. Specifically, pp02 and co-inoculation significantly increased the Dyella and Pseudomonas population. Firmicutes, Mycobacteria, and Proteobacteria phyla were enriched in Bacillus PP02 samples. These may explain the best growth-promoting effects of pp02 and co-inoculation on hybrid Pennisetum under greenhouse conditions. Our findings reveal the performance of endophytic bacterial inoculants in enhancing beneficial microbiota, salt stress tolerance, and hybrid Pennisetum growth.
摘要:
盐碱土威胁农业,在全球范围内降低生长和作物产量。在这项研究中,理化和分子技术用于探索耐卤碱内生细菌菌株Sphingomonassp的潜力。pp01,芽孢杆菌。pp02,Pantoeasp.pp04和肠杆菌。pp06在不同的盐水条件下增强杂交狼尾草的生长。菌株表现出对高盐浓度的耐受性,碱性pH,和高温。在受控条件下,所有四个菌株对单独或组合接种的杂交狼尾草均显示出显着的生长促进作用。然而,在沿海盐渍土壤中,这种影响显着降低。在温室条件下取得了最佳的促生长效果,杂交狼尾草的芽鲜重和干重分别增加了457.7%和374.7%,分别,使用灌溉试验。宏基因组测序分析表明,接种内生细菌后,根际微生物的多样性和组成发生了显着变化。具体来说,pp02和共同接种显著增加了Dyella和假单胞菌种群。Firmicutes,分枝杆菌,和变形杆菌门富集在芽孢杆菌PP02样品中。这些可以解释pp02和共同接种在温室条件下对杂交狼尾草的最佳生长促进作用。我们的发现揭示了内生细菌接种剂在增强有益微生物群中的性能,耐盐胁迫,和杂交狼尾草的生长。