Plant growth-promoting bacteria belonging to the genera <em>Pseudomonas</em> and <em>Bacillus</em> improve the growth of sorghum seedings in a low-nutrient soil

Abstract

Background: Deficiency in sorghum growth in ecosystems of low-nutrient soils has been scarcely studied. This soil deficiency can be overcome by the addition of plant growth-promoting bacteria which increase sorghum growth.&#x0D; Questions and/or Hypotheses: indole acetic acid (IAA) producing and phosphate solubilizing bacteria can promote sorghum growth under nutritional stress.&#x0D; Studied species: Sorghum bicolor (L.) Moench.&#x0D; Study site and dates: Mexico City, 2018.&#x0D; Methods: Of the twelve bacterial strains utilized, three produce IAA (group BI), two strains produce IAA and siderophores (BIS group), four strains produce IAA and solubilize phosphate (BIP group), and three strains produce IAA, solubilize phosphate, and produce siderophores (BIPS group). Hydroponic bioassays and low-nutrient soil bioassay were used.&#x0D; Results: In hydroponic bioassays, for BI and BIS groups, five strains significantly increased the growth parameters with respect to the control, and for the BIP and BIPS groups, two strains promoted stem development and shoot dry weight. In a low-nutrient soil bioassay, Pseudomonas sp. BI-1 (from BI group) was the one that presented the highest percentages 32, 48, 140 and 79 % in stem diameter, height and dry weight of the shoot and dry weight of the root, respectively, followed by the P. mohnii BIPS-10 strain (from BIPS group) that exhibited similar results.&#x0D; Conclusions: IAA producing Pseudomonas strains improve the sorghum growth in a low-nutrient soil and suggest thatPseudomonas sp. BI-1 and P. mohnii BIPS-10 could be used as potential bioinoculants for sorghum.

Seed Endophyte bacteria enhance drought stress tolerance in Hordeum vulgare by regulating, physiological characteristics, antioxidants and minerals uptake

“…Similarly, under water deficit, Pseudomonas preferentially increased shoot K+, retained root Na + , and enhanced the shott K + /Na + ratio relative to the other treatments. De Inoculation of Pseudomonas increased seedling growth in low fertile soil by compensating for nutrient deficiency through the synthesis of plant growth-promoting hormones at the root interface, stimulating root development and increasing soil water and nutrient absorption ( Amora-Lazcano et al., 2022 ; Mehrasa et al., 2022 ).…”

The Use of PGPB to Promote Plant Hydroponic Growth

“…A mixture of Bacillus spp. increased phosphorus solubilization for lettuce and increased yields [ 105 ] PGPB identified in a sorghum trial included a range of the phosphorus solubilizing bacteria Pseudomonas spp., Burkholderia spp., Phylobacterium spp., and Chitinophaga japonensis [ 108 ]. Phosphate solubilization is a common trait of Pseudomonas spp.…”

“…Many strains of Pseudomonas fluorescens have been documented as having both IAA and ACC deaminase in more recent research [ 128 ]. Indeed, IAA and ACC deaminase producing Pseudomonas outperformed other isolates in sorghum [ 108 ], switchgrass [ 109 , 110 ], and tomato trials [ 111 ]. Single organisms with the ability to produce both hormones and increase nutrient uptake frequently perform the best in both soil and hydroponic systems [ 86 ].…”