LEAF CHARACTERISTICS AND GRAIN YIELD OF PINTO BEAN CULTIVARS UNDERSALT STRESS

Effects of four levels of salinity (0, 4, 8 and 12 dS m-1NaCl) on leaf characteristics and grain yield of three pinto bean cultivars (COS16, Talash and Khomain) were investigated in 2010. A factorial experiment based on randomized complete block design with three replications was carried out at the Greenhouse of the University of Tabriz, Iran. Ten seeds were sown in each pot filled with 900 g perlite. After emergence, seedlings were thinned and 4 plants were kept in each pot. Leaf chlorophyll content index (CCI), leaf temperature, leaf water content, proline accumulation, leaf area index (LAI), specific leaf weight (SLW) and grain yield per plant were significantly affected by salinity and cultivar. SLW, leaf temperature and proline content of pinto bean leaves increased, but the leaf water percentage, LAI and CCI considerably decreased as a result of salt stress. COS16 had the highest leaf water percentage and leaf area index (LAI) and the lowest leaf specific weight (SLW) and leaf temperature. However the highest chlorophyll content index (CCI) and proline content were found in Talash, compared with other cultivars.