Research Projects

The weed microbiome is a beneficial resource which helps in plant-growth promotion and provides stress amelioration. Microbes obtained from various spheres of weeds might act as an important resource and may serve as an interesting inoculum for improving plant-growth parameters, health and stress tolerance. Also, the weed-associated microbiota plays a crucial role to strive in various environmental extremities. But, due to domestication, crop plants are no more capable of recruiting some beneficial microbes resulting in compromised plant resilience (Perez-Jaramillo, Mendes and Raaijmakers, 2015) whereas weeds/crop wild relatives recruit various beneficial rhizospheric microbes and exert a positive feedback interaction with the microbiomes (Massenssini et al., 2014). In this context weed management practices aim to not completely eradicate the weeds from the crop field but reduce the growth of weeds to such a limit that the valuable microbes are conserved and provide plant-beneficial functions Mimosa diplotricha is a fast-growing weed and can tolerate a wide range of external perturbations. Recently, in my laboratory at Gauhati University, we explored the rhizospheric microbes of M. diplotricha and identified two isolates which are endowed with various plant growth-promoting traits. The isolates are identified as Pseudomonas aeruginosa and Variovorax sp. The initial screening and biochemical characterization of the isolates were conducted in my laboratory at Gauhati University. In the initial experiment, they also exhibited drought tolerance in the rice seedlings/plants. In the proposed project we endeavoured to carry out a detailed study on the protective role of the two above-mentioned microbes in rice seedlings/plants, which may be very useful for the development of an effective biostimulant for drought stress mitigation. Due to climate change, the world is facing an increasing drought situation and microbe-based solutions for stress mitigation are considered the most eco-friendly approach. Metagenomic analysis of 16s rRNA genes from the rhizosphere helps in the determination of bacterial abundance in a sample. Since the microbiome associated with the host plant plays a key role in alleviating the stress effects, thus the use of metagenomics will make it easier to determine the dominant major microbial phyla involved in plant beneficial functions. Further, the secretion of root exudates by the plants themselves, under various circumstances attracts beneficial below-ground microbes to thrive in any harsh situation. Thus, the overall, study will help in determining the effect of NA 15 and NA 16 on drought stress alleviation in rice seedlings/plants and finally, a correlation between the change in root exudation, plant-associated microbiome and microbes-derived chemicals will be established. The study will help in devising an effective drought-mitigation protocol/method based on non-synthetic chemical uses.