The rhizosphere of any plant is a dynamic landscape which includes multiple microbial collaborations. The microflora in the rhizosphere forms an indispensable part of plant’s growth by providing access to nutrients and safeguarding from pathogens as well. However, does the dynamics of microbial population changes over the course of plant’s growth and follows ecological succession is albeit known. Also, if succession is favored, how does the plant selects a particular species of microbial partner and how does an organism conquers the diversity and become a dominant species with respect to the plant is less known. Here we address ecological succession with population dynamics in the rhizosphere of Coriandrum sativum grown in an arid region like Solapur, India. The plant is short-lived and therefore eases the study. Continuous microbial profiling of rhizosphere of the plant from its germination till maturity was analysed and the diversity of population was identified by various biochemical analysis. Also, reasons for establishment of dominance from microbial and plant's perspective was analysed biochemically.
Results/Conclusions:
The population census followed an initial diversity with succession of two species of bacteria viz. Pseudomonas aureofaciens and Bacillus species as the plant matured. The release of an indigenous pigment cum antibiotic by Pseudomonas aureofaciens helped in establishing its dominance among the population. The effect of this antibiosis by the pigment was checked on the indigenous diversity and was proved to be valid enough. However, Bacillus species was found to resist the antibiosis probably due to its sporulating lifestyle. Secondly, the plant selected the organism because of its ability to produce a Plant Growth Promoting hormone i.e., Indole Acetic Acid(IAA). The study portrays a classical epitome of ecological succession and probable factors that aided succession as a paradigm of plant-microbial interaction. Understanding the ecology of plant in its respective habitat and its interactions with microbial partners are very crucial in designing what additional supplements are to be supplied to enhance the plant’s growth. Also, this knowledge of ecological succession of microflora can also be of paramount importance in development of natural plant favored microbial cultures to enhance productivity and health of the plant.