Identification and development of drought-tolerant cocoa hybrids: physiological insights for enhanced water use efficiency under water stress conditions

This experiment indicated how the plants were able to regulate various physiological mechanisms under drought stress and how these parameters can be utilized in distinguishing between drought tolerant and susceptible plants. Ranking based on the values of physiological parameters revealed that crosses M 13.12 x G I 5.9, G II 19.5 x G VI 55, and G II 19.5 x G I 5.9 produced hybrids with favourable responses to drought tolerance. It indicated that these crosses could be further utilized in developing drought-tolerant genotypes. Further, the binary regression studies indicated that relative water content and photosynthetic rate can be used as selection parameters to identify drought-tolerant hybrids more efficiently in the future cocoa stress breeding programmes.