Chickpea (Cicer arietinum L.) is an important food crop grown under rainfed conditions in Mediterranean regions in which drought is a major limiting factor for production. In these areas little attention is given to legumes, and efforts to identify drought-tolerant genotypes are primarily focused on major cereal crops. | Research Article Turk J Agric For 34 (2010) 257-264 © TÜBİTAK doi: Plant water relations and photosynthetic activity in three Tunisian chickpea (Cicer arietinum L.) genotypes subjected to drought Abdelmajid KROUMA* Laboratory of Extremophile Plants, Centre of Biotechnology, Borj Cedria Ecopark, BP 901, Hammam Lif 2050. TUNISIA Received: 2009 Abstract: Chickpea (Cicer arietinum L.) is an important food crop grown under rainfed conditions in Mediterranean regions in which drought is a major limiting factor for production. In these areas little attention is given to legumes, and efforts to identify drought-tolerant genotypes are primarily focused on major cereal crops. In the current study a greenhouse experiment was conducted to assess the effects of drought stress on plant growth, photosynthesis, and water relations in 3 Tunisian chickpea genotypes (Cicer arietinum L.). Drought was applied, and soil humidity was maintained at 30% of field capacity (stressed plants) or 100% of field capacity (control plants) for 3 weeks. A close relationship between plant growth, and photosynthesis and leaf water status was observed. In comparison to Chetoui and Kesseb, Amdoun exhibited the greatest plant growth and photosynthetic activity, the lowest drought intensity index, and important osmotic adjustment under drought stress. Water use efficiency clearly differentiated the studied genotypes. Key words: Drought, Cicer arietinum, photosynthesis, water potential, osmotic adjustment, water use efficiency Introduction Chickpea (Cicer arietinum L) is one of the world’s most important, but lesser-studied, leguminous food crops, grown on nearly 10 million hectares across the Americas, the Mediterranean basin, East Africa, the Middle East, Asia, and Australia (Jayashree et al. 2005). While in the developed world it represents a valuable crop for export, in the developing world it provides a protein-rich supplement to cereal-based diets. Chickpea seed contains .