Effect of Mannitol Induced Drought Stress on Yield and Morphological Traits in Chilli (Capsicum annum) Genotypes

Abstract

Chilli (Capsicum annuum L.) is a globally important vegetable and spice crop valued for its nutritional and industrial significance; however, its productivity and quality are highly sensitive to drought stress, which disrupts physiological and biochemical processes. Despite extensive research, limited understanding exists on genotype-specific biochemical responses under controlled drought conditions, highlighting the need for systematic evaluation to identify stress-tolerant and nutritionally superior genotypes. This study investigates the impact of mannitol-induced drought stress on yield performance and related traits in two chilli genotypes, Pusa Jwala and Pusa Sadabahar. Drought stress was simulated using varying concentrations of mannitol (100–250 mM) under controlled conditions. The results indicated a significant decline in all yield parameters, including fruit length, fruit diameter, seed weight, number of fruits per plant, and total yield with increasing stress intensity. Both genotypes showed maximum growth and yield under control conditions, while severe reduction was observed at 250 mM mannitol. Pusa Sadabahar exhibited comparatively better tolerance, maintaining higher values for most yield traits than Pusa Jwala. The reduction in yield attributes is mainly attributed to impaired physiological processes such as reduced photosynthesis, nutrient transport, and cell expansion under water deficit conditions. Statistical analysis confirmed significant variation among treatments and genotypes. The study highlights the importance of evaluating yield components for screening drought-tolerant varieties. Overall, Pusa Sadabahar emerged as a more resilient genotype under drought stress conditions. These findings provide valuable insights for breeding programs aimed at improving drought tolerance in chilli crops.