Rs-198液体有机菌肥制备及其促生性能研究

为简化液体有机菌肥的制备工艺,将液体有机肥和植物根际促生菌Pseudomonas putida Rs-198复配,分析Rs-198液体有机菌肥的制备工艺、稳定性及其对萝卜幼苗促生能力的影响。结果表明:液体有机肥的最佳稀释倍数为5倍;Rs-198在稀释液体有机肥中的最佳培养条件为30℃、140 r/min、装液量100 mL;摇瓶发酵36 h时,菌体密度最大可达4.6×10^(9)CFU/mL;制备的Rs-198液体有机菌肥室温储存28 d后有效活菌数为2×10^(7)CFU/mL;膨润土作为其最佳营养助剂,有效活菌数提高了60.2%。液体有机菌肥可显著提高萝卜幼苗生物量,其中株高、鲜重和干重分别增加19.6%、22.2%和17.6%,萝卜叶片中可溶性糖和可溶性蛋白含量分别提高49.4%和12.4%,Rs-198液体有机菌肥应用前景良好。

生物炭基Rs-198菌剂对辣椒的耐盐促生性能研究

针对土壤盐渍化问题日益严重,创新性的将生物炭与植物根际促生菌(PGPR,Plant growth-promoting rhizobacteria)有效结合,以更好地实现提高作物耐盐碱性和促进作物生长的目的。本研究将生物炭基Rs-198菌剂(BBRs,Biochar inoculated Pseudomonas putida Rs-198)应用到盐胁迫条件下生长的辣椒植物中,探究BBRs菌剂在盐胁迫下的功效和缓解盐胁迫的机理。结果表明,在0.5%NaCl胁迫下,与空白对照CK2相比,BBRs2处理的辣椒株高、根长、鲜重和干重分别增加了26.43%、24.27%、42.59%和50.00%。茎粗、叶面积、叶片数和相对水分含量分别提高了23.41%、14.03%、12.79%和3.54%。叶绿素a、b分别增加了47.22%和62.50%。可溶性蛋白、可溶糖、脯氨酸和电解质渗透率分别降低了33.07%、57.78%、62.20%和36.88%。SOD、PPO和POD分别降低了35.68%、31.85%和37.20%。表明BBRs通过降低渗透物质和抗氧化酶的积累缓解了盐胁迫,促进了辣椒生长,为解决盐胁迫问题提供了思路和方法,有利于农业可持续发展。

Preparation of slow-release regulated Rs-198 bilayer microcapsules and application of its lyophilized bacterial inoculant on Capsicum annuum L.under salt stress

The survival adaptation of bacteria in saline soil is poor.The bilayer microcapsules were prepared by secondary embedding of monolayer sodium alginate(NaAlg)-bentonite(Bent)-sodium carboxy-methylcellulose(CMC)microcapsules wrapped with plant growth promoting rhizobacteria(PGPR)Pseudomonas putida Rs-198 by chitosan solution to promote the synergistic effect of bilayer microen-capsulation and PGPR.The characterization of the Rs-198 bilayer microcapsules showed that the amino and carboxyl groups were cross-linked and a thin layer of chitosan was formed on the outside of the microcapsule.The bilayer microcapsule(Ch-d)with a chitosan concentration of 0.8 wt%and pH 6 showed a slow release of bacteria with a maximum release of 6.06 × 10^(9) cfu/g on the 7th day.The viable bacteria of Ch-d increased by 4.42%after 60 days of storage compared with monolayer microcapsules.The 0.9 wt%L-cysteine,10 wt%glycerinum,10 wt%trehalose and 12 wt%soluble starch were added as bacterial protective agents during the process of preparing the Ch-d lyophilized bacterial inoculant(Ch-d LBI).Pot experiments showed that Ch-d LBI exhibited better growth promotion of Capsicum annuum L.under salt stress.Therefore,the bilayer microcapsule as slow-release bacterial inoculant is a potential alternative for sustainable agriculture.