Effect of Fluorescent-Producing Rhizobacteria on Cereal Growth Through Siderophore Exertion

Abstract

Despite soil having an abundance of iron (Fe), it is unavailable for proper plant growth and development. One of the mechanisms plants use to deal with iron deficiency is the uptake of iron by chelating phytosiderophores. Pseudomonas fluorescence can produce pyoverdine-type siderophore and has potential application in agriculture as an iron chelator. Therefore, bacterial isolates collected from different areas of district Faisalabad were screened for their fluorescent, siderophore production and indole acetic acid equivalents. After selecting efficient strains from a screening test, they were evaluated for improving wheat and maize production under field conditions. The results showed that out of 15 isolates, 7 were found to have significant plant-beneficial microbial traits. Efficient strains promoted grain yield by 24.2% and 20.2%, plant height by 30.9% and 23.7%, total grain weight by 25.3% and 13.4% over control in wheat and maize, respectively. Similarly, significant improvements in the number of grains per cob/spike were also observed. Analyses of grain iron contents depicted 67% increase as compared to control in for maize. Therefore, based on the results, it is concluded that bio-fortification of cereal crops through fluorescent producing siderophoric microbes is an effective strategy favorable for plant growth and development through nutrient solubilization/mobilization.

Roles of rhizobacteria in cereals

“…Cereals such as maize, rice, wheat, barley, rye, and sorghum, are staple foods of the majority of the world population, and their cultivation covers a large proportion of arable lands. Plant growth-promoting rhizobacteria from cereals have therefore been studied as a sustainable, eco-friendly approach in various agricultural aspects such as soil nutrient supplements and biocontrol agents [2,6]. There is evidence for PGPR inoculations to enhance crop yield, and plant growth, and alter the microbial population in the soil (Table 4).…”

“…Diazotrophic soil bacteria such as Rhizobium are members of the PGPR [2]. Siderophore-producing bacteria are involved in iron sequestration for plants [6,27]. Some of the PGPRs such as Rhizobium, Azospirillum, Pseudomonas, Flavobacterium, Arthrobacter, and Bacillus have been identified to enhance tolerance to abiotic stresses such as high salinity [27].…”