Trend of changes for morpho-physiological characteristics of chickpea (Cicer arietinum L.) under salinity stress (NaCl) condition

Salinity is one of the most important widespread abiotic stresses which causes toxic and nutritional effects as well as loss of water absorption ability by plants. Plants respond to salinity with morphological changes. Due to high susceptibility of chickpea to salt stress، some physiological and morphological responses occur following the stress in this plant. Thus، different concentrations of salt stress (0، 8، 12 dS. m-1) impacts on morphophysiological characteristics were studied in candidate chickpea genotypes; a factorial experiment in a completely randomized design was performed with three replications and four sampling times of one week interval. The results indicated that the most tolerant and susceptible genotype to salinity were MCC760 and MCC806، respectively. By increasing the concentration of sodium chloride at week 4، root dry weight to shoot dry weight ratio increased 0. 8 and 2 folds in these genotypes but root dry weight decreased 1. 7 and 4 folds. At high stress level (12 dS. m-1)، MCC760 genotype had not only the more photosynthetic pigments (including chlorophyll a، b and carotenoids) but also the rate was less in which its chlorophyll stability index (75%) was significantly higher than the others، indicating more than 30% significant differences compared with MCC806. The third week determined as more appropriate time to compare the physiological parameters in which MCC760 and MCC806 genotypes with 1. 8 and 3. 4 folds had significant difference and lowest relative water content. Overall، the data showed that MCC760 was the most tolerant genotype in response to salinity in this study and also the appropriate time for tolerant assessment were 4th and 3rd weeks after sowing based on Morphological and physiological parameters، respectively.