مطالعه اثرات سطوح شوري و نيتروژن بر محتوي نيتروژن ارقام گندم نان

Effects of salinity and nitrogen levels on nitrogen content of wheat cultivars (Triticum aestivum L.)

One of the adverse effects to plants in the presence of salinity is the reduction in nitrogen uptake. The objective of this experiment was to determine response of wheat cultivars (cvs) CRll(Iranian salt-tolerant), Ghods(Iranian salt-sensitive) and Kharchia - 65 (as standard salt-tolerant) to the rate of shoot and root nitrogen accumulation at anthesis and harvest maturity when exposed to different concentrations: 0, 100, 200 and 300 mol m-3 of mixture of NaCl and CaCl2 in 5:1 molar ratio and three levels of amonium nitrate (0, 2 and 4 mol. m-3 ) in semi-controlled environment and sand culture medium. The results showed that, although nitrogen accumulation was decreased with increasing level of salinity specially before anthesis, but the nitrogen concentration in different organs (roots, leaf, stem and grain) was not changed necessarily, and depend on plant ability to nitrogen absorption and biomass production, the cultivars responded differently to salinity. N application at 100 and 200 mol.m"3 of salinity caused better nitrogen uptake efficiency and nitrogen utilization efficiency and consequently better nitrogen use efficiency and rise in N content, but at 300 mol.m-3 of salinity, nitrogen not only did not adverse effects of salinity but also caused a reduction in nitrogen content of plant. Although, nitrogen reduced the adverse effects of salinity, however the form of nitrogen is important and it needs to be studied in detail.