Assessment of the role of Pseudomonas fluorescence L on growth promoting of Maize (Zea mays L), wheat (Triticum aestivum L) and Sorghum (Sorghum bicolor L)

Abstract

The utilization of synthetic composts and pesticides has caused harm to the environment. These agents are both dangerous to humans and animals, and may persist and accumulate in natural ecosystem and a response to this issue is supplanting chemicals with organic methodologies, which are viewed as more environment friendly in the long haul (Suman et al., 2016). One of the rising examination territories for the control of various phytopathogenic specialists is the utilization of plant growth promoting rhizobaceria, which are capable of preventing the phytopathogen from harm. Pseudomonas fluorescence representing a group of PGPR can advancement development and suppress plant pathogens by various systems (Nihorimbere et al., 2011). Plant growth promoting rhizobacteria can exhibit a variety of characteristics responsible for influencing plant growth. An effective PGPR should have at least three characters of promoting plant activities which are phytostimulator, root colonization competency and bio control agent against plant pathogens (Bloemberg et al., 2001). PGPR colonize the plant rhizosphere or inside the plant body (as endophytes) and promote plant growth by providing fundamental nutrients to plants (Kaur et al., 2016). Most of the microbes that colonize the rhizosphere include bacteria, fungi, acticomycetes, protozoa, and algae. However, bacteria are the most abundant microbial present in the rhizosphere. Some genera of bacteria have been determined as PGPR including Pseudomonas, Bacillus, Azospirillum, Azotobacter, and Bradyrhizobium (Wahyudi et al.,2011). Since many species and strains of bacteria residing in rhizosphere have been shown to possess plant growth promoting traits they are collectively designated as PGPR. Bacteria promote plant growth in three different ways: synthesizing growth promoting hormones for the plants, facilitating the uptake of nutrients from the soil, and lessening or preventing the plants from diseases. The function of these microbial populations is well known and proven by their role in improving plant growth (Vejan et al., 2016). Plant growth promoting rhizobacteria were firstly proposed by Kloepper et al. (1980) and used mainly for the Pseudomonas fluorescence involved in biological control of pathogens and the enhancement of plant growth. Later, Kapulnik et al. (1981) extended to rhizobacteria capable of promoting directly the plant growth. Nowadays, this expression is used to refer to all bacteria living in the rhizosphere, improving plant growth by one or several methods (Haghighi et al., 2011).