Improving Drought Tolerance in Mungbean (Vigna radiata L. Wilczek): Morpho-Physiological, Biochemical and Molecular Perspectives

Chandra Mohan Singh,Aditya Pratap,Chandrakant Tiwari,Poornima Singh,Smita Singh,Mukul Kumar,Vishal Chugh,Awdhesh Kumar Mishra,Shalini Purwar

doi:10.3390/agronomy11081534

Abstract

Drought stress is considered a severe threat to crop production. It adversely affects the morpho-physiological, biochemical and molecular functions of the plants, especially in short duration crops like mungbean. In the past few decades, significant progress has been made towards enhancing climate resilience in legumes through classical and next-generation breeding coupled with omics approaches. Various defence mechanisms have been reported as key players in crop adaptation to drought stress. Many researchers have identified potential donors, QTLs/genes and candidate genes associated to drought tolerance-related traits. However, cloning and exploitation of these loci/gene(s) in breeding programmes are still limited. To bridge the gap between theoretical research and practical breeding, we need to reveal the omics-assisted genetic variations associated with drought tolerance in mungbean to tackle this stress. Furthermore, the use of wild relatives in breeding programmes for drought tolerance is also limited and needs to be focused. Even after six years of decoding the whole genome sequence of mungbean, the genome-wide characterization and expression of various gene families and transcriptional factors are still lacking. Due to the complex nature of drought tolerance, it also requires integrating high throughput multi-omics approaches to increase breeding efficiency and genomic selection for rapid genetic gains to develop drought-tolerant mungbean cultivars. This review highlights the impact of drought stress on mungbean and mitigation strategies for breeding high-yielding drought-tolerant mungbean varieties through classical and modern omics technologies.

Highlights

Mungbean is the third most important grain legume after chickpea and pigeon pea
We summarize the progress made on drought stress tolerance in the mungbean by previous workers and highlight the gaps along with mitigation strategies for future research
Prospects Drought stress affects mungbean at different growth stages with varying severity, which leads to moderate to severe yield loss

Summary

Introduction

Mungbean is the third most important grain legume after chickpea and pigeon pea. It is predominantly cultivated across the Asian countries and has expanded to some parts of Africa, Australia and South America [1,2]. There is an utmost need to develop drought-tolerant varieties to improve crop productivity to ensure farmers’ nutritional and livelihood security, especially under the changing climate The diverse mechanisms such as drought escape, drought avoidance, and drought tolerance are involved in the adoption of drought stress that enables the plants to survive, accumulate dry matter and produce seed [34]. Nair et al [16] highlighted the effect of various biotic and abiotic constraints and breeding progress made so far They emphasized the impact of RNAi-technology for improving the stress tolerance in the mungbean and suggested utilizing high throughput phenotyping platforms against particular stress to develop a suitable mitigation strategy. We summarize the progress made on drought stress tolerance in the mungbean by previous workers and highlight the gaps along with mitigation strategies for future research

Morpho-Physiological Trait Variations for Improving Drought Tolerance

Biochemical Traits Modulating Drought Tolerance

Conclusions and Future Prospects

Findings