Effect of nitrogen on germination, initial growth, proline and nitrate reductase activity of Borage under salinity stress

Subject Areas :

Mehdi  Aghighi Shahverdi ¹ (Ph.D Student of Crop Physiology Faculty of Agriculture Shahed University)
Heshmat  Omidi ² (Assistant Professor Faculty of Agricultural Sciences Shahed University Tehran, Iran)
Abdolamir  Bostani ³ (Assistant Professors Faculty of Agricultural Sciences Shahed University)

Received: 2015-07-23 Accepted : 2016-01-16 Published : 2016-02-20

Keywords: o plant nutrition, o ammonium, o NaCl, o nitrate,

Abstract :

ABSTRACT   The current study was conducted to evaluate the effects of the nitrogen on borage seed germination under saline stress. The experiment was in a factorial based on completely randomized design with three replications. The experimental factors were salinity stress including 0, 3, 6, 9 and 12 ds.m-1 and five ratio of nitrogen source nutrition, NO3-:NH4+ (100:0, 75:25, 50:50, 25:75 and 0:100). The effect of salinity and also effect of salinity and nitrogen source on growth and physiological traits including dry weight, proline content, nitrogen and nitrate reductase activity was investigated. Increasing salinity levels caused a significant decrease of seed germination and seedling dry weight. Nitrogen nutrition with ratio 50% of ammonium with increasing proline in high salinity conditions, to moderate the negative effects of stress, in contrast, by increasing the amount of ammonium than nitrate, nitrate reductase activity and total seedling growth decreased and salinity showed more negative effects, so that the seedling growth of 75 and 100% ammonium was stopped. Amount of nitrogen in terms of more nitrate than ammonium negative correlation with salinity, and conversely by increasing the amount of ammonium than nitrate showed a positive relationship. Applications of nitrogen source with NO3- by rate of more 50% is suggesting for obtaining uppermost germination indices.