the effect of different levels of salinity stress on some physiological characteristics of saffron (crocus sativus l.)

Salinity is a common stress in many parts of the world especially in Iran that decreases the yield and quality of many crops. In order to investigate the effects of different levels of salinity stress on some physiological indices of saffron, an experiment was conducted in the Malayer University in 2012. The experiment was arranged based on a completely randomized design (CRD) with four replications and six levels of salinity (i.e. 0, 2, 4, 6, 8 and 10 dS m-1). The results showed that the effect of salinity on chlorophyll a and chlorophyll b content was not significant. However, increasing the salinity stress up to 6 dS m-1 resulted in an increase of these photosynthetic pigments. The effect of salinity stress on leaf carotenoides and xantophyll content were significant and higher salinity stress resulted in an increase of these pigments. Moreover, the effect of salinity on leaf proline was not significant, but the amount of leaf glucose content increased by increasing salinity stress, significantly. The effects of experimental treatments on leaf dry weight, leaf length and relative water content were significant and negative, but there was no significant effect on leaf number. By increasing the concentration of salt, the mean weight of replacement corms decreased significantly whereas the corms number increased up to 4 dS.m-1 and then decreased significantly.