Identification of multi-trait PGPR isolates and evaluating their potential as inoculants for wheat

Abstract

Development of an effective plant growth promoting rhizobacteria (PGPR) inoculant necessitates the presence of a diverse set of traits that can help its colonization of the rhizosphere and survival under varying environmental conditions. In our investigation, a set of 100 bacterial isolates from the rhizosphere of wheat plants were screened initially on the basis of a seed germination assay; ten bacterial isolates (AW1-AW10) were selected. These isolates were then tested in vitro for specific PGPR traits, such as the production of IAA, siderophore, ammonia, HCN, P solubilization, ACC deaminase activity, acetylene reduction assay and antifungal activity. Of the ten isolates, AW5 was found to be promising for all PGP attributes. An experiment undertaken in the controlled conditions of the National Phytotron Facility revealed the potential of three isolates (AW1, AW5 and AW7) in enhancing the growth parameters of wheat plants. Characterization of these isolates using polyphasic approaches involving both phenotypic and genotypic attributes led to their identification as Bacillus sp. (AW1), Providencia sp. (AW5), and Brevundimonas diminuta (AW7), respectively. These strains could prove effective PGPR inoculants as they possess a number of traits useful for their establishment and proliferation in soil. The genus Providencia is reported for the first time for its PGP potential, using cultural as well as functional attributes to show its suitability as an inoculant for wheat crop.

Nutrient Concentration in Vegetative Organs of the Orchid <i>Laelia anceps</i> subsp. <i>anceps</i> Based on Mineral Fertilization and Biofertilization

“…1 and 2). According to Rana et al (2011), PGPR enhanced the uptake of N, P, and micronutrients in treated plants, which can partially explain our results.…”

Evaluation of Rhizospheric Bacteria from Ocimum sp. as Potential Pgpr

“…(AW5) and Alcaligenes sp. (AW10) possess ACC deaminase activity (3.13 and 9.5 μm α-ketobutyrate/mg/h, respectively) [2]. In our study, the two isolates showed activity of 3.90×10 -6 μmol α-keto butyrate/ mg protein/ h and 2.92×10 -6 μmol α-keto butyrate/mg protein/h by isolate UHI(II)7 and CHII(II)K7.…”

“…They offer an attractive way for sustainable agricultural system by reducing the use of chemical fertilizers [1][2][3]. Most of the world population still relies mainly on herbal products and medicines for health care [4,5].…”

The persistence and performance of phosphate-solubilizing Gluconacetobacter liquefaciens qzr14 in a cucumber soil

“…P-solubilization was further determined using the Mo-blue method (Chen et al 2006). Indoleacetic acid (IAA) and siderophore production were measured using Salkowski reagents and CAS medium, respectively (Rana et al 2011).…”