PROMOTING SALT TOLERANCE IN WHEAT SEEDLINGS BY APPLICATION OF NITROGEN FERTILIZER

Salinity is one of the primary abiotic stresses limiting crop production, especially in arid and semi-arid areas. This study was conducted to examine if nitrogen fertilizer could alleviate the adverse impacts of salinity on wheat (Triticum aestivum L.) seedling emergence, seedling growth characteristic and physiological responses. Two wheat varieties (Xumai30 and Elnilein) were sown into soil treated with NaCl at levels of 1.4, 2.5, 4.2, and 7.6 dS m(-1) . The saline soil was fertilized with three nitrogen levels as urea fertilizer (0, 86, and 210 kg N ha(-1)). The emergence percentage, root and shoot length, and total dry weight were significantly affected by the interaction among the varieties, nitrogen, and salinity. The interaction between nitrogen and salinity was impacted the seedling vigor index (SVI). Superoxide dismutase (SOD) and protein were increased with increasing nitrogen level and decreased in salt-stressed plants. The antioxidant enzymes of peroxidase (POD) and catalase (CAT), were increased with increasing salinity level. This study revealed that nitrogen was successful for alleviating the adverse effects of NaCl. Furthermore, 86 and 210 kg Nha(-1) had similar effects on wheat seedling emergence, seedling growth and physiological responses. Moreover, results revealed that nitrogen fertilizer at moderate salinity exerted a positive affect on wheat plants while at high salt concentration had negative affect or remained ineffective. Therefore, fertilizers management is required in the salt-affected areas to sustain yield and to decrease the degradation of soil.