Biopriming of Solanum lycopersicum seeds with novel root endophytic bacterial consortium retrieved from halotolerant Sundarban mangroves to sustain growth and yield with salt resilience

Abstract

Mangroves are often found in coastal areas and tropical wetlands that can withstand high salinity. We hypothesized that endophytes that are harbouring in the roots of mangrove plants may improve the innate immunity of host plants to survive naturally in saline environment. Retrieving these endophytes and sequential characterization may function as a novel bio-effector for non-host food crops as well. We focused on the integrated approach towards formulating a novel bacterial consortium. Thirty-one bacterial endophytes isolated from the roots of mangrove plants were screened for plant growth promoting potential by inoculating our model crop (Tomato). Seven most promising isolates impacting plant growth were identified. In-vitro plant growth promoting characters were also analysed. The root colonization by the isolates was confirmed by Scanning Electron Microscopy (SEM). Among the screened isolates, four of them were found to be compatible with each other when grown together and were selected to formulate a novel biostimulant consortia. The consortia treated Tomato plants exhibited superior phenological characters. In the pot experiment, plant height of the treated plants was about ≈43 cm while the non-treated plants under salt stress could grow only up to a height of ≈26 cm. Similarly, a total fruit yield of ≈6.8 kg was observed in case of treated plants under salt stress whereas the non-treated plants under salt stress could only produce ≈4.7 kg of fruit. This study demonstrated that the beneficial bacteria inhabiting in mangrove roots can increase the potential of conferring salt tolerance to non-host crops, thereby contributing to sustainable agriculture.