Plant Growth-Promoting Rhizobacteria Play a Role as Phytostimulators for Sustainable Agriculture

  • Sapna Gupta
  • Ruchi SethEmail author
  • Anima Sharma


During the past few decades, increasing use of chemical fertilizers has caused many negative effects in agriculture: development of infectious agent resistance, adverse impact on nontarget species, and reduction in crop yield resulting from the harmful effects of chemical fertilizers on soil quality parameters. Thus, the search for an eco-friendly approach has been emphasized during the past several years. Plant growth-promoting rhizobacteria (PGPR) perform varied functions as (1) biofertilizers, (2) phytostimulators, (3) rhizoremediators, and (4) biopesticides. Plants do not seem to be axenic in natural conditions, and typically are influenced directly by completely different microorganisms such as rhizobacteria, of which several have the ability to provide phytohormones. This chapter sums up data relating to the synthesis, metabolism, regulation, physiological role, and agronomic impact of plant products made by plant growth-promoting rhizobacteria. We have included information regarding the auxins, cytokinins, gibberellins, and ethylene.


Biofertilizers Auxins Cytokinins Gibberellins Ethylenes 



Some of the research in the present review has been supported in part by JECRC University, Jaipur, and Rajasthan. The author acknowledges Mr. Anukool Vaishnav for his careful review of the content and for improvement of the text. The author also thanks Mr. Mohit Agrawal and Mr. Gaurav Kaushik for valuable suggestions and guidance.


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Authors and Affiliations

  1. 1.JECRC UniversityJaipurIndia

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