Rice Drought Tolerance: Emerging Molecular Breeding Strategies in the Post-genomic Era

Abstract

Global food security is threatened owing to the rapid change in climatic conditions. Rice, the predominant cereal crop, faces brutal drought severity, where the development of tolerant rice varieties becomes cumbersome with traditional breeding methods. Nevertheless, with the development of advanced technologies, we are leaping into the era of molecular breeding. Therefore, breeding drought-tolerant rice cultivars is possible. In recent times, one aspect of advancement has been using DNA-based molecular markers closely linked to the economically desired trait or trait of interest, or QTLs, to develop drought-tolerant cultivars. And the process of marker-assisted selection (MAS) enables the transfer of desirable stocks of genes with drought-driven characters into a single genotype. One major setback in traditional breeding is the longer breeding cycle. Therefore, the emerging new techniques like rapid generation advancement (RGA) and speed breeding have the onus to accelerate plant development and generation turnover, thereby reducing the varietal breeding time and enhancing the genetic gain. Moreover, the fastest-growing accessibility of genome sequencing has motivated genomics-assisted breeding (GAB) approaches such as NGS-based genotyping and haplotype-based breeding. Thus, the key to tackling the world’s escalating population with billions of mouths to feed is smart breeding strategies, which are the need of the hour in this post-genomic era. Here, we discuss traditional and emerging advanced breeding strategies used to develop climate-smart rice cultivars.