Salt Stress Effects on Respiration and Growth of Germinated Seeds of Different Wheat (Triticum aestivum L.) Cultivars

Abstract

Abstract: Establishment of seedlings at early growth stages of crop plants as one of the most important determinants of high yield is severely affected by soil salinity. Therefore, high germination rate and vigorous early growth under salty soils is preferred. In this study salt tolerance of wheat cultivars were examined at germination and seedling growth stages. Seeds were germinated and grown in long dark cups using distilled water as control and two levels of salt stress imposed by 9 and 15 ds/m NaCl solution for 48 hours. Coleoptile and root growth was measured as the response of cultivars to salinity. Seedling respiration was expressed as the difference between initial seed weight and seedling dry weight after 48 hours. Significant differences were found among cultivars in terms of coleoptile and root growth under salt stress condition. Differences among cultivars in terms of respiration rate were also significant indicating that genetic variation exists among wheat cultivars. It was also found that seedling respiration was decreased as salinity level was increased. Significant correlation coefficients were found between coleoptile growth and respiration under all condition. Salt stress inhibited coleoptile growth more than root growth. It was concluded that wheat seedling maintenance respiration is higher that what is estimated for C plants. 3 Key words: Salt stress Respiration Germination Wheat