Influence of nitrogen and salinity levels on yield, nitrogen uptake, nitrate concentration and chlorophyll content of spinach and some properties of post-harvest soil in a calcareous soil

摘要

A greenhouse experiment was conducted to evaluate the effect of nitrogen (N) and salinity on dry matter yield, N uptake, nitrate (NO3-) concentration, agronomic efficiency (AE), physiologic efficiency (PE), apparent nitrogen recovery (ANR) and chlorophyll content of spinach shoots (cv. Viroflay), and also total N, NO3-N and electrical conductivity of post-harvest soil. The experiment was factorial, arranged as a completely randomized design with three replications. Treatments included five N rates (0, 75, 150, 225, and 300 mg/kg soil, as urea) and four salinity levels (0, 1, 2 and 3 g NaCl per kg soil). Results showed that application of 1 and 2 g NaCl had no significant effect on shoot yield of spinach. But application of 3 g NaCl significantly decreased shoot yield. Addition of salinity had no significant effect on plant NO3? concentration, leaf chlorophyll readings, AE and ANR of shoots, and total N of post-harvest soil but reduced PE. Increasing N rate increased yield, total N uptake and chlorophyll readings of shoots, and total N of post-harvest soil: but reduced AE and PE. Application of high N level intensified the negative effects of 3 g NaCl salinity on reduction of spinach shoots' yield. Under the present experimental conditions, salinity tolerance level of Viroflay cultivar was higher than 8 dS/m, which is much more than the level reported in most references for spinach (2 dS/m). Application of 225 mg N (without salinity application) was the best N level for dry matter yield of spinach. Keywords: Sodium chloride, Agronomic efficiency, Physiologic efficiency, Chlorophyll. Full-Text Type of Study: Research | Received: 2013/02/19 Send email to the article author Related Websites Scientific Publications Commission - Health Ministry Scientific Publications Commission - Science Ministry Yektaweb Company Site Keywords ?????, Academic Journal, Scientific Article, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ?? Vote ? 2015 All Rights Reserved | Journal of Science and Technology of Greenhouse Culture -Isfahan University of Technology