Abiotic Stress Responses and Tolerance Mechanisms for Sustaining Crop Productivity in Sugarcane

Sugarcane (Saccharum species hybrids) is a long duration, high-water-requiring agroeconomic crop cultivated in various climatic conditions. Being a long duration crop, it faces vagaries of climate all the year-round affecting plant growth and development, synthesis of sugar, its accumulation and recovery, and ratooning ability. Climate change brings an increase in greenhouse gases (GHGs), temperature, extreme events, drought, heavy rainfall, western disturbance, changes in the level of the sea, etc. and culminates into multiple abiotic stresses affecting soil health, growth, and development of cane and its chemical composition, ripening, and availability of the seed cane. Besides, it aggravates some other abiotic and biotic stresses augmenting the losses further. But, sugarcane is relatively more resilient to abiotic stresses probably due to some natural endowments like a good deal of compensatory ability, C4 photosynthesis, higher-temperature optima for most of the growth processes except sugar accumulation, higher water-use efficiency, and genetic components from Saccharum spontaneum. All these characteristics impart tolerance in sugarcane to various abiotic stresses and carbon sequestration as phytoliths, etc. which helps reduce the damaging impact of various abiotic stresses. Further, the development of climate-resilient sugarcane varieties and technological interventions for stress management may mitigate the impact of climate change-induced multiple abiotic stresses and sustain sugarcane and sugar productivity. Physiological interventions like inducing drought hardiness, deeper root system, reduction of heat load by trash mulching, increasing the age of the crop at the advent of moisture stress, organic matter amendment in the soil, nutrient management, managing rhizospheric salinity/alkalinity, etc. also contribute to elevate its stress tolerance. A number of genes, molecular markers, and miRNAs related with abiotic stress response also contribute to the resilience of sugarcane to abiotic stresses.