The pot experiment entitled “Effect of integrated application bio-fertilizer and soil amendments on Growth parameters Groundnut (Arachis hypogaea L.)’’ was conducted at the Research Farm School Agriculture, ITM University, during kharif season 2022. experimental field sandy loam, having a pH 8.13, EC 0.54 ds m-1, organic carbon 0.40%, available N, P, K 180, 11.09 283.40 kg ha-1 respectively exc...

Flavonoids in root exudate of leguminous plants activate the transcription of Rhizobium genes involved in the formation of root nodules (nod genes). We report that inoculation with the homologous symbiont R. leguminosarum bv. viciae results in an increased nod gene-inducing activity (Ini) in root exudate of V. sativa subsp. nigra, whereas inoculation with heterologous Rhizobium strains results ...

A total of 155 nodule isolates that originated from seven sites in Northwest China were characterized by PCR-RFLP of the 16S rRNA gene and sequence analysis of multiple core genes (16S rRNA, recA, atpD, and glnII) in order to investigate the diversity and biogeography of Glycine soja-nodulating rhizobia. Among the isolates, 80 were Ensifer fredii, 19 were Ensifer morelense, 49 were Rhizobium ra...

Microbial exopolysaccharides (EPSs) play key roles in plant-microbe interactions, such as biofilm formation on plant roots and legume nodulation by rhizobia. Here, we focused on the function of an EPS produced by Rhizobium sp. YAS34 in the colonization and biofilm formation on non-legume plant roots (Arabidopsis thaliana and Brassica napus). Using random transposon mutagenesis, we isolated an E...

A pot trial was designed to investigate the impact of Rhizobium inoculation and/or sodium benzoate application on performance of two contrasting fababean varieties i.e., Giza Blanka (salt tolerant) and Giza 634 (salt sensitive) grown in sandy soil under two levels of salinity (3000 and 6000 ppm). High salinity (6000 ppm) greatly reduced nodules formation in both varieties. Rhizobium inoculation...

Gas chromatographic and mass spectrometric analyses of derivatized culture medium extracts were used to identify the products of flavonoid metabolism by rhizobia. A number of Rhizobium species and biovars degraded their nod gene-inducing flavonoids by mechanisms which originated in a cleavage of the C-ring of the molecule and which yielded conserved A- and B-ring products among the metabolites....

To differentiate among the roles of the three nodD genes of Rhizobium meliloti 1021, we studied the activation of a nodC-lacZ fusion by each of the three nodD genes in response to root exudates from several R. meliloti host plants and in response to the flavone luteolin. We found (i) that the nodD1 and nodD2 products (NodD1 and NodD2) responded differently to root exudates from a variety of hos...

A field experiment was conducted for two consecutive seasons (2009/10 and 2010/11) in the Demonstration Farm of the Faculty of Agriculture at Shambat-Sudan, to study the interactive effect of nitrogen fertilization and rhizobium inoculation on nodulation and yield of soybean (Glycine max [L.] Merrill) plants. The experiment was laid out in a randomized complete block design with four replicatio...

Rhizobium fredii is a fast-growing rhizobium isolated from the primitive Chinese soybean cultivar Peking and from the wild soybean Glycine soja. This rhizobium harbors nif genes on 150- to 200-megadalton plasmids. By passage on acridine orange plates, we obtained a mutant of R. fredii USDA 206 cured of the 197-megadalton plasmid (USDA 206C) which carries both nif and nod genes. This strain, how...

PREMISE OF THE STUDY Resource mutualisms such as the symbiosis between legumes and nitrogen-fixing rhizobia are context dependent and are sensitive to various aspects of the environment, including nitrogen (N) addition. Mutualist hosts such as legumes are also thought to use mechanisms such as partner choice to discriminate among potential symbionts that vary in partner quality (fitness benefit...