*Physiological and Molecular Adaptation of Sugarcane under Drought vis-a-vis Root System Traits DOI: http://dx.doi.org/10.5772/intechopen.103795*

The severe drought causes the complete failure of crop and sucrose recovery. India is the largest consumer and the second-largest producer of sugar in the world. The average annual production of sugarcane is around 35.5 crore tonnes which is used to produce 3 crore tonnes of sugar. In India, most of the country's irrigation facilities are utilized by paddy and sugarcane, depleting water availability for other crops. Pressure on water due to sugarcane cultivation in States like Maharashtra has become a serious concern, calling for more efficient and sustainable water use through alternative cropping pattern. This is especially important in regions where groundwater use has reached a critical and overexploited stage or where more than 50% surface water is used for irrigating sugarcane alone. Drought is a serious problem, but under production processing. There are various strategies to solve this obstacle, C4 plants are often considered to have mastered the art of drought control particularly as they are able to maintain leaf photosynthesis with closed stomata. Generally, C4 plants have high water use efficiencies (WUEs), and the presence of the CO2-concentrating mechanisms makes C4 photosynthesis more competitive in conditions that promote carbon loss through photorespiration, such as high temperatures, high light intensities, and decreased water availability [13]. C4 photosynthesis is characterized by the presence of a metabolic CO2 pump that concentrates CO2 in the vicinity of the main enzyme of carbon dioxide fixation, ribulose-1,5-bisphosphate carboxylase/oxygenase [13, 14]. This confers several important advantages in terms of WUE because it allows high rates of photosynthesis to occur even when stomata are closed while limiting flux through the photo-respiratory pathway [14]. Therefore, an emergent choice for sustainable sugarcane production is the identification of water-efficient cultivars or providing water for irrigation.
