Effectiveness of Seed priming with Polyamines in Decreasing Drought Stress Adversities in Two Wheat Cultivars

Abstract

Two cultivars of bread Wheat (Triticum aestivum), Miser2 and Sakha 94 (Differ in their drought tolerance) were selected for drought and Polyamines (PAs) treatment. Seeds of both cultivars were presoaked in water or 100 μM solutions of either putrescine (put) spermines (spm) separately or in mixture for 10 h. Thereafter, all seedlings (OR) germinated seeds were restricted to drought by withholding water beginning from the seventh day after sowing (DAS) for a total experimental period of 21days. The results revealed that drought caused significant decrease in growth parameters, pigments, total protein contents, total insoluble sugars, antioxidant enzymes activities and membrane stability index in both cultivars. The decrease was more pronounced in Sakha94.The level of proline, total soluble sugars, H2O2 and lipid peroxidation increased under drought stress in Misr2 more than in Sakha 94 confirming thatMisr2 is more tolerant.Presoaking seeds in putrescine solutions accumulated pigments, proline, soluble and insoluble sugars and total protein however; it decreased H2O2 content and lipid peroxidation in Sakha 94, but soaking in spermine increased catalase activity while pretreatment with the mixture increased guaiacol peroxidase activity in Sakha94 only. The little effect of presoaking with polyamines was most detected in Misr2. In conclusion, presoaking with spm and/ or put play to some extent a protective role against drought stress through improving plant tolerance. This response differs according to the cultivar but more future research will be carried about PAs application as foliar spray.