Drought stress responses and adaptive strategies in Indian mustard: A comprehensive review

Abstract

Indian mustard (Brassica juncea (L.) Czern. & Coss.) contributes significantly to the edible oil production and an important oilseed crop for rural livelihoods in the semi-arid region and grown extensively in regions like India, China and South Asia. However, its productivity is severely constrained by repeated drought stress, particularly in arid and semi-arid areas. Drought stress adversely affects Indian mustard at morphological, physiological, biochemical and molecular levels, disrupting water relations, photosynthesis, nutrient uptake and metabolic activities. In response, the crop develops adaptive strategies including deep rooting, solute accumulation, antioxidant enzyme regulation, hormonal modulation and gene level metabolic adjustments. Understanding these drought-tolerance mechanisms is essential. Drought management strategies can partially mitigate yield losses, improving crop efficiency by 20–40  % under moderate stress conditions, although residual yield losses of 10–30 % may still occur depending on stress severity and genotype. Modern molecular breeding methods can be complemented with high throughput screening technologies to improve drought tolerance and mitigate repercussions. This review aims to provide a comprehensive understanding of drought stress responses and adaptive strategies in Indian mustard to support the development of resilient cultivars under changing climate scenarios.