Indian Journal of Plant Physiology

Chickpea (Cicer arietinum L.) cultivar Pusa 1108 was grown inside open top chambers (OTCs) and exposed to ambient (CA, 370±20 μl l⁻¹) and elevated (CE, 550±50 μl l⁻¹) CO₂ from germination to maturity of the crop to determine its growth and yield response. The plants exposed to elevated CO₂ showed increase in growth characteristics, viz. shoot length, total number of branches and leaf area per plant. Significant increase in leaf and shoot dry weight was recorded in elevated CO₂ grown plants. The concentration of non structural carbohydrates such as sugars and starch in leaves was higher under elevated CO₂ grown plants, which indicated higher photosynthetic activity. Total carbon concentration increased but the nitrogen concentration decreased in the leaves and resulted in higher C/N ratio. The seed yield of elevated CO₂ grown plants was higher due to significant increase in number of seeds per plant. This study suggests that rising atmospheric CO₂ in future may increase dry matter production and yield in chickpea but reduction in nitrogen concentration may alter their protein levels.