Journal of Agronomy and Field Innovations

Background: Cicer arietinum L. (chickpea) is a major grain legume, whose productivity is affected by simultaneous heat and drought stress. The consequences of the two kinds of stress acting together is not the same as the collective effect.
Objectives: This study evaluated the physiological and biochemical responses of chickpea genotypes to individual and combined heat and drought stress, with emphasis on photosynthetic performance and stress tolerance indicators.
Materials and Methods: In a randomized experimental design, three chickpea cultivars (BG-372, JG-11, and ICCV-2) were cultivated in four different environmental conditions: control, heat stress, drought stress, and dual heat-drought stress. The researchers were interested in examining the parameters of photosynthesis, chlorophyll fluorescence, and the activity of antioxidant enzymes as well as the level of osmolytes, oxidative stress indicators, and membrane stability. In order to analyze the results a range of statistical methods were applied, including ANOVA and Tukey's test.
Results: The simultaneous effect of heat and drought stress brought about the maximum decline in the photosynthetic rate, stomatal conductance, and photosystem II efficiency while substantially inducing oxidative stress. Under this stress condition, there was a considerable increase in the proline, soluble sugars, and antioxidant enzyme activities, demonstrating the elevated defense mechanisms against the environmental stress. The only genotype ICCV-2 exhibited the best physiological behavior, having the ability to cope with oxidative stress in conditions of simultaneous drought and heat stress.
Conclusion: The simultaneous presence of both heat and drought stress causes more serious physiological damage to the plants than the case with one or the other stress situation. Therefore, with the integration of chlorophyll fluorescence technique, gas exchange measurements, and biochemical markers it is possible to identify climate-resilient chickpea genotypes, which will be helpful in further breeding programs.