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http://dx.doi.org/10.5352/JLS.2019.29.11.1281

Current Perspectives on the Effects of Plant Growth-promoting Rhizobacteria  

Le, Thien Tu Huynh (Department of Applied Bioscience, Graduate School of Natural Science, Dong-A University)
Jun, Sang Eun (Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University)
Kim, Gyung-Tae (Department of Applied Bioscience, Graduate School of Natural Science, Dong-A University)
Publication Information
Journal of Life Science / v.29, no.11, 2019 , pp. 1281-1293 More about this Journal
Abstract
The rhizosphere is the active zone where plant roots communicate with the soil microbiome, each responding to the other's signals. The soil microbiome within the rhizosphere that is beneficial to plant growth and productivity is known as plant growth-promoting rhizobacteria (PGPR). PGPR take part in many pivotal plant processes, including plant growth, development, immunity, and productivity, by influencing acquisition and utilization of nutrient molecules, regulation of phytohormone biosynthesis, signaling, and response, and resistance to biotic- and abiotic-stresses. PGPR also produce secondary compounds and volatile organic compounds (VOCs) that elicit plant growth. Moreover, plant roots exude attractants that cause PGPR to aggregate in the rhizosphere zone for colonization, improving soil properties and protecting plants against pathogenic factors. The interactions between PGPR and plant roots in rhizosphere are essential and interdependent. Many studies have reported that PGPR function in multiple ways under the same or diverse conditions, directly and indirectly. This review focuses on the roles and strategies of PGPR in enhancing nutrient acquisition by nutrient fixation/solubilization/mineralization, inducing plant growth regulators/phytohormones, and promoting growth and development of root and shoot by affecting cell division, elongation, and differentiation. We also summarize the current knowledge of the effects of PGPR and the soil microbiota on plants.
Keywords
Nutrient; PGPR; phytohormone; plant growth and development; rhizosphere;
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