Department of Microbiology, Punjab Agricultural University, Ludhiana, 141004, India.
Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, 141004, India.
World J Microbiol Biotechnol. 2019 Oct 31;35(11):172. doi: 10.1007/s11274-019-2752-4.
The present study was designed with the objective of improving growth and nodulation of soybean [Glycine max (L.) Merill] with co-inoculation of native Bradyrhizobium sp. (LSBR-3) (KF906140) and non-rhizobial nodule endophytic diazotroph Leclercia adecarboxylata (LSE-1) (KX925974) with multifunctional plant growth promoting (PGP) traits in cereal based cropping system (Rice-Wheat). A total of 40 endophytic bacteria from cultivated and wild sp. of soybean were screened for multifarious PGP traits and pathogenicity test. Based on PGP traits, antagonistic activities and bio-safety test; L. adecarboxylata (LSE-1) was identified with 16 S rRNA gene sequencing along with the presence of nifH (nitrogen fixation) and ipdc (IAA production) genes. Dual inoculant LSE-1 and LSBR-3 increased indole acetic acid (IAA), P & Zn-solubilization, 1-aminocyclopropane-1-carboxylate deaminase (ACCD) activity, siderophore, biofilm formation and exo-polysaccharides in contrast to single inoculation treatment. Further, assessment of dual inoculant LSBR-3 + LSE-1 improved growth parameters, nodulation, soil enzymes activities, nutrient accumulation and yield as compared to single as well as un-inoculated control treatment under field conditions. Single inoculant LSBR-3 improved yield by 8.84% over control. Further, enhancement of 4.15% grain yield was noticed with LSBR-3 + LSE-1 over LSBR-3 alone treatment. Application of LSBR-3 + LSE-1 gave superior B:C ratio (1.29) and additional income approximately 116 USD ha in contrast to control treatment. The present results thus, is the first report of novel endophytic diazotroph L. adecarboxylata (LSE-1) as PGPR from Indian conditions particularly in Punjab region for exploiting as potential PGPR along with Bradyrhizobium sp. (LSBR-3) in soybean.
本研究旨在通过共接种土著慢生根瘤菌（LSBR-3）（KF906140）和非根瘤内生固氮菌亮发菌（LSE-1）（KX925974），提高谷类作物系统（水稻-小麦）中大豆的生长和结瘤。从栽培和野生大豆中筛选了总共 40 种内生细菌，以筛选各种促生长（PGP）特性和致病性试验。基于 PGP 特性、拮抗活性和生物安全性试验；通过 16S rRNA 基因测序鉴定亮发菌（LSE-1），并存在 nifH（固氮）和 ipdc（IAA 生产）基因。与单一接种处理相比，双接种 LSE-1 和 LSBR-3 增加了吲哚乙酸（IAA）、P 和 Zn 溶解、1-氨基环丙烷-1-羧酸脱氨酶（ACCD）活性、铁载体、生物膜形成和外多糖。此外，与单接种和未接种对照处理相比，双接种 LSBR-3+LSE-1 改善了田间条件下的生长参数、结瘤、土壤酶活性、养分积累和产量。与对照相比，单接种 LSBR-3 使产量提高了 8.84%。此外，LSBR-3+LSE-1 的应用使产量比 LSBR-3 单独处理提高了 4.15%。与对照处理相比，LSBR-3+LSE-1 表现出更高的 B:C 比（1.29）和额外收入约 116 美元/公顷。因此，本研究结果首次报道了来自印度，特别是旁遮普邦的新型内生固氮菌亮发菌（LSE-1）作为 PGPR，可与慢生根瘤菌（LSBR-3）一起在大豆中发挥潜在的 PGPR 作用。
