Dal'Rio Isabella, Lopes Eliene Dos Santos, Santaren Karen Caroline Ferreira, Rosado Alexandre Soares, Seldin Lucy
Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
Bioscience, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
Front Microbiol. 2024 Feb 23;15:1356891. doi: 10.3389/fmicb.2024.1356891. eCollection 2024.
L. is a versatile edible plant that is widely explored due to its medicinal properties and as a key element in intercropping systems. Its growth could be improved by the use of biofertilizers that can enhance nutrient uptake by the plant or provide tolerance to different abiotic and biotic stresses. In a previous study, 101 endophytes isolated from roots showed more than three plant growth-promoting (PGP) features , such as phosphate mineralization/solubilization, production of siderophores, antimicrobial substances and indole-related compounds, and presence of the gene. To provide sustainable alternatives for biofertilization, the genomes of two promising endophytes-CAPE95 and CAPE238-were sequenced to uncover metabolic pathways related to biofertilization. Greenhouse experiments were conducted with 216 seeds and 60 seedlings, half co-inoculated with the endophytes (treatment) and half inoculated with 1X PBS (control), and the impact of the co-inoculation on the plant's bacteriome was accessed through 16S rRNA gene metabarcoding. The strains CAPE95 and CAPE238 were taxonomically assigned as and , respectively. Metabolic pathways related to the enhancement of nutrient availability (nitrogen fixation, sulfate-sulfur assimilation), biosynthesis of phytohormones (indole-3-acetic acid precursors) and antimicrobial substances (bacilysin, paenibacillin) were found in their genomes. The experiments showed that treated seeds exhibited faster germination, with a 20.3% higher germination index than the control on the eleventh day of the experiment. Additionally, treated seedlings showed significantly higher plant height and leaf diameters ( < 0.05). The bacterial community of the treated plants was significantly different from that of the control plants ( < 0.001) and showed a higher richness and diversity of species (Chao and Shannon indexes, < 0.001). A higher relative abundance of potential synergistic PGP bacteria was also shown in the bacteriome of the treated plants, such as and . For the first time, co-inoculation of and was shown to have great potential for application as a biofertilizer to plants. The bacterial consortium used here could also be explored in other plant species in the future.
L. 是一种用途广泛的可食用植物，因其药用特性以及作为间作系统中的关键元素而被广泛研究。使用生物肥料可以促进其生长，生物肥料能够增强植物对养分的吸收，或使其对不同的非生物和生物胁迫具有耐受性。在之前的一项研究中，从根部分离出的101种内生菌表现出三种以上促进植物生长（PGP）的特性，如磷矿化/溶解、铁载体、抗菌物质和吲哚相关化合物的产生，以及相关基因的存在。为了提供生物施肥的可持续替代方案，对两种有前景的内生菌CAPE95和CAPE238的基因组进行了测序，以揭示与生物施肥相关的代谢途径。用216颗种子和60株幼苗进行了温室试验，一半与内生菌共同接种（处理组），一半接种1X PBS（对照组），并通过16S rRNA基因宏条形码分析共同接种对植物细菌群落的影响。菌株CAPE95和CAPE238在分类学上分别被归类为 和 。在它们的基因组中发现了与提高养分有效性（固氮、硫酸盐 - 硫同化）、植物激素（吲哚 - 3 - 乙酸前体）生物合成以及抗菌物质（杆菌溶素、类芽孢杆菌素）相关的代谢途径。实验表明，处理过的种子发芽更快，在实验的第11天，发芽指数比对照组高20.3%。此外，处理过的幼苗株高和叶片直径显著更高（ ＜0.05）。处理过的植物的细菌群落与对照植物的细菌群落显著不同（ ＜0.001），并且显示出更高的物种丰富度和多样性（Chao和Shannon指数， ＜0.001）。在处理过的植物的细菌群落中，潜在协同PGP细菌的相对丰度也更高，如 和 。首次表明， 和 的共同接种作为生物肥料应用于 植物具有巨大潜力。这里使用的细菌联合体未来也可在其他植物物种中进行探索。
