Physiological and Morphological Responses of White Clover (Trifolium repens) and Red Clover (Trifolium pratense) Plants to Salinity Stress

Trifolium spp. are native plants in iran exhibiting good ground cover potential.salinity is a major environmental stress and today, 20% of the worldcultivated areas and nearly half of all irrigated lands are affected by salinity.the main aim of this research was to study morphological and physiologicaladaptations of these native species under different salinity levels for urbanlandscape usage. for this purpose a factorial experiment based on completelyrandomized design (crd) with 4 replicates was conducted. plants of trifoliumrepens and two trifolium pratense species (native and commercial) weresubmitted to salinity stress in a pot experiment with 4 different salinity levels(0, 75, 150, 225 mm nacl) during the experiment period. leaf area, lrwc(leaf relative water content), electrolyte leakage, root and shoot length and rootand shoot fresh and dry weight were measured. results showed significant differenceswithin salinity treatments in all 3 species studied. highest valuesmeasured for traits in cultivars were observed in t. pratense commercialfollowed by t. pratense native and t. repens except electrolyte leakage and rootfresh weight. but salinity effect on these species increased along with severity,linearly. leaf area was most affected and decreased to 40.21 mm2 (225 mm)from 184.14 mm2 in control. generally trifolium species showed sensitivity tosalinity stress, especially in higher levels. this study should help understandsome physiological and morphological responses of trifolium species to salinitystress for urban landscape projects, parks and xeriscapes in iran.