Identification of drought tolerant turmeric (Curcuma longa L.) genotypes with sustainable yield.

Turmeric (Curcuma longa L.) (Zingiberaceae), is native to south west India. Water stress is the most common adverse environmental condition which severely affects crop productivity. Here we have analysed morphology, stomatal density, relative water content, electrolyte leakage, epicuticular wax content and rhizome yield of 50 elite turmeric genotypes for identification of genotypes with differential response (tolerance and susceptibility) to water stress. Results showed that water stress during rhizome development stage (90-120 days after planting) significantly decreased the leaf relative water content and increased membrane permeability. Epicuticular wax content varied significantly among the genotypes. Genotypes with lower leaf area, higher relative water content, lesser electrolyte leakage, higher wax content and fewer stomata than other genotypes were shortlisted as tolerant. From among these shortlisted ones, four tolerant genotypes (IISR Pragati, SL 5, Suguna, and Suvarna) with higher yield, along with two susceptible genotypes (IISR Alleppey Supreme and IISR Kedaram), were further evaluated in field conditions. The results indicated that, in terms of yield and physiological parameters, the tolerant genotypes significantly outperformed the susceptible ones, showcasing superior drought tolerance traits. These genotypes with contrasting characters can be used for further studies to elucidate the mechanism of drought tolerance. [ABSTRACT FROM AUTHOR]