Genotypic variation of Physiological and Biochemical traits in new elite arabica (Coffea arabica L.) Coffee hybrids under different soil moisture regimes

A study has been done using eight elite arabica hybrids of coffee for assessing genotypic differences in physiological and biochemical traits. Arabica genotypes exhibit variability in their sensitivity to moisture stress. Under the crop's adaptive mechanism, abiotic challenges may modify not only the overall expression of genetic traits but also the physiological processes of plants. Identification and categorization of drought-resistant plant species would then be made easier by an understanding and critical assessment of physiological changes, including photosynthetic characteristics brought on by soil moisture stress. Therefore, new elite arabica hybrids were studied for their differences in growth and development, biochemical traits and carbon exchange rate (CER) in different soil moisture regimes at Central Coffee Research Institute. During the study S.4813, S.4820 and S.4814 were found to be physiologically efficient genotypes with high Carbon exchange rates types. These genotypes also showed better development and growth in comparison to other genotypes with high leaf areas, leaf dry weight, specific leaf weight (SLW) as well as specific leaf area (SLA), which play a direct role in higher photosynthesis production of a plant. Further, these genotypes were also found to have high antioxidant enzyme activity and other biochemical parameters like high carbohydrate content, higher chlorophyll fractions and epicuticular wax content. The study revealed that S.4814, followed by S.4813 and S.4820, are found to be superior genotypes with higher stress adaptability and with potential to yield more under abiotic stress conditions. Hence, these elite hybrids could be used in further breeding programs to develop drought tolerance genotypes.