Molecular advances in plant root system architecture response and redesigning for improved performance under unfavorable environments

Abstract

A future challenge in crop improvement, mostly driven by global unfavorable environment variables, is to develop climate smart crops that are competent for multiple biotic and abiotic stresses. Researchers have addressed the elementary mechanism focused on aboveground plant organs, as extensive study on root traits are very confined. Moreover, most of our knowledge regarding root research is limited to certain developmental aspects, while a direct connectivity to developing environment sensitive roots under various stresses is extremely urgent to explore thoroughly. Therefore this chapter covers the most recent research on the root system architecture (RSA) of different crop species with regard to different extreme environmental variables such as high temperature, elevated CO2, low temperature, drought, excess water, and stressed soil. We highlight the recent physiological, genetic, and molecular strategies used in the rapid advancement of RSA traits under these stresses. There is an urgent need to explore RSA in order to improve crop stress tolerance, therefore we discuss and explore the link between RSA and stress tolerance. Further, this chapter will provide new insights into the relevance of the redesign and selection of improved RSA for the development of climate resilient plants. We conclude by discussing the functional and molecular evidence of RSA components such as deep root weight, root length density, root volume, root penetration, and other root traits for improving root plasticity in a fluctuating environment, which will help the researchers to select RSA pipelines for abiotic stress resilience and crop improvement programs. © 2021 Elsevier Inc. All rights reserved.