Metagenomics of Sugarcane Rhizosphere for Sustainable Productivity in the Changing Environment: A Review

Abstract

Sugarcane (Saccharum officinarum L.) is one of the most valuable cash crops globally. However, continuous monoculture practices, excessive fertilizer application, and soil disruption due to various economic activities have led to the degradation of soil quality, ultimately impacting crop productivity. The rhizosphere is the area where plant roots and soil connect and this zone consist of many different microbes that boost crop productivity by making nutrients accessible, synthesizing growth regulating hormones, and preventing growth of pathogenic microbes. Generally, culturable microbes get well characterized and documented while non culturable micobes get neglected in different studies. Hence in the present review article an emphasis is given to explain the roles played by uncultured microbial populations, particularly in rhizosphere. The functions of Bradyrhizobium, Pseudomonas, Streptomyces, and Burkholderia in pathogen control, phosphate solubilization, nitrogen fixation, and phytohormone synthesis, have been highlighted. The advances in metagenomics such as 16S rRNA gene sequencing and analysing function genes, have greatly increased our ability to understand microbial diversity and their role in crop productivity. Further, metagenomic studies of rhizospheric microbiomes have a great potential in increasing the efficiency of sugarcane productivity without detriment to natural resources, by developing bioinoculants and biocontrol agents.