Plant Growth Promoting Rhizobacteria (PGPR): A Bioprotectant bioinoculant for Sustainable Agrobiology. A Review

Abstract

Plant growth promoting rhizobacteria (PGPR) involves the utilization of large array of soil bacteria to improve yield and plant growth. As free living and symbiotic rhizobacteria, PGPR colonizes extracellular and/or intracellular rhizoenvironment in search for carbon source while indirectly aiding plant growth. In the past few decades, focus has been on developing a biosafety agro base approach void of continuous burden on soil micro flora as a result of agrochemical application. However, with clear understanding of PGPR mechanisms of action; (i) biofertilization (ii) biostimulation (iii) and biocontrol, it create more hope on the possibility of curbing food insecurity, clean environmental sustenance and lower public health risk. Seeds or soil application of PGPRs inoculant enhances directly phosphates solubilization, atmospheric nitrogen fixation and secretion of plant hormones (indole acetic acid, gibberellins, cytokinins and ethylene) needed for growth and adaptation in stressed environment. As soil pathogen consistently rival the roles of these organisms, they (PGPRs)have developed over time wide spectrum of strategies in the form of systemic resistance, iron, space and nutrient competition, antibiotics synthesis, lytic acid production and hydrogen cyanide for efficient food productivity. In view of this, the review widen our scope on the use of PGPR as bioinoculant in sustainable agro practice and to serve as a wakeup call for it reception and implementation in the tropics where paucity of data on it use has long prevailed.

Plant Growth Promoting Rhizobacteria (PGPR): A Novel Agent for Sustainable Food Production

“…PGPR exhibit a special role by hindering plant infestation with disease, increase nutrient absorption, enhance root and shoot formation, improve seed germination and making the plant more tolerant to most environmental stress (Arora et al, 2008;Lugtenberg and Kamilova, 2009). Interestingly, these organisms have been accrued with fascinating roles ranging from enhanced nitrogen fixation through nodule formation, solubilization of phosphates, production of phytohormones such gibberellins, siderophores, indole acetic acid and serving as low molecular weight agents that modulate plant growth and development (Ma et al, 2009;Odoh, 2017).…”

“…Its causes membrane and zoospore damage in Pythium sp. These antibiotics acts as an inhibitor to aldose reductase, an enzyme involved in metabolism of glucose to fructose (Odoh et al, 2017). Phenazine also enhances the survival of bacteria in anaerobic conditions using endogenous phenazines, as withnessed in the survival of P. aeruginosa facilitated by extracellular electron transfer (Wang et al, 2010).…”

Seed treatment using rhizobacteria as plant growth promotion of two chili variety (Capsicum annuum L.)

“…Theiincrease of plant height"wasithoughtitoibeicloselyirelateditoitheiroleiofitheseirhizobacteriaias PGPR.iTheiabilityiofirhizobacteriaitoitheiproductioniofiIAAianditheiabilityitoidissolveiphosphate previously.iTreatmentiof seeds withiPGPRirhizobacteriaiplaysianiimportantirole,iespeciallyibeneficial initheiprocess of seed germination [12]. ApplicationiofiPGPRienhancesidirectly phosphates solubilization, atmospheric nitrogen fixation and secretion of plant hormones (indole acetic acid, gibberellins, cytokinins and ethylene) needed for growth [13]. Admittedly, PGPRihaveibeenireported toiimproveitheigrowthiofiaivarietyioficropispecies, such as tomato [14], redipepper [15], maizei [16], mungibean [17][18], and lettucei [19].…”

Bacterias rizosféricas con beneficios potenciales en la agricultura

“…Muchas rizobacterias secretan moléculas que eliminan o disminuyen el crecimiento de algunos f itopatógenos mediante la inhibición de la síntesis de pared celular, la desestabilización estructural de la membrana celular o la inhibición de la traducción en los f itopatógenos, entre otros (Beneduzi et al, 2012). La producción de antibióticos es una de las estrategias de biocontrol más estudiadas de las rizobacterias e incluyen una amplia variedad de antibióticos (amf isina, 2,4-diacetilfloroglucinol (DAPG), oomicina-A, fenazina, piroluteorina, pirrolnitrina, tensina, oligomicina A, kanosamina, zwittermicina A y xantobaccina) (Odoh, 2017). Algunos géneros de rizobacterias productoras de antibióticos corresponden a Burkholderia (Tenorio-Salgado et al, 2013), Streptomyces (Rajesh y Prakash, 2011), Bacillus, Pseudomonas y Stenotrophomonas (Odoh, 2017).…”

“…La producción de antibióticos es una de las estrategias de biocontrol más estudiadas de las rizobacterias e incluyen una amplia variedad de antibióticos (amf isina, 2,4-diacetilfloroglucinol (DAPG), oomicina-A, fenazina, piroluteorina, pirrolnitrina, tensina, oligomicina A, kanosamina, zwittermicina A y xantobaccina) (Odoh, 2017). Algunos géneros de rizobacterias productoras de antibióticos corresponden a Burkholderia (Tenorio-Salgado et al, 2013), Streptomyces (Rajesh y Prakash, 2011), Bacillus, Pseudomonas y Stenotrophomonas (Odoh, 2017). Producción de sideróforos.…”