Effect of nitrate nutrition on tolerance of sudangrass plants to salinity

Authors

  • Alexcyane Feijão Universidade Federal do Ceará
  • Júlio Silva Universidade Federal do Ceará
  • Elton Marques Universidade Federal do Ceará
  • José Prisco Universidade Federal do Ceará
  • Enéas Gomes-Filho Universidade Federal do Ceará

Keywords:

Growth, Salt stress, Nitrogen, Inorganic and organic solutes, Sorghum sudanense

Abstract

This work aimed to study the effect of NO3- nutrition on growth, on gas exchange and on inorganic and organic solutes accumulation of sudangrass plants subjected to salinity. Plants were grown in hydroponic medium and kept in a greenhouse. The experiment was a completely randomized design, following a factorial arrangement of 2 (NO3- at 0,5 mM or 8,0 mM) x 2 (NaCl at 0 mM or 100 mM), with five replications. All data were subjected to analysis of variance and the means were compared by Tukey’s test at 5% of significance. Salinity reduced leaf area and dry weight of shoots and roots. However, plants growing in the 8.0 mM NO3- increased more than those growing in 0.5 mM. The stomatal conductance, photosynthesis, transpiration and the relationship between internal and external concentration of CO2 were increased by better nutrition NO3-. Na+ and Cl- contents were significantly increased by salinity in leaves and roots and the K+ content was reduced only in the roots. Nevertheless, plants fed with 8.0 mM NO3- had the lowest contents of Na+ and Cl- in leaves under salt stress. Salinity increased proline and amino acid contents and the higher NO3- concentration promoted the accumulation of these solutes in roots of stressed plants. Proper nutrition for NO3- was able to reduce deleterious effects of salinity in sudangrass plants.

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Published

2011-05-30

Issue

Section

Crop Science