Back to Search
Start Over
Physiological and biochemical responses of the forage legume Trifolium alexandrinum to different saline conditions and nitrogen levels
- Source :
- Journal of plant research. 129(3)
- Publication Year :
- 2015
-
Abstract
- Salinity stress reduces plant productivity, but low levels of salinity often increase plant growth rates in some species. We herein describe the effects of salinity on plant growth while focusing on nitrogen use. We treated Trifolium alexandrinum with two nitrogen concentrations and salinity levels and determined growth rates, mineral concentrations, nitrogen use efficiency, photosynthesis rates, and nitrate reductase (NR, E.C. 1.6.6.1) and glutamine synthetase (GS, EC 6.3.1.2) activities. The T. alexandrinum growth rate increased following treatment with 100 mM NaCl in low nitrogen (LN) and high nitrogen (HN) conditions. Salt treatment also increased root volume, intrinsic water use efficiency, and nitrogen use efficiency in LN and HN conditions. These changes likely contributed to higher biomass production. Salinity also increased accumulations of sodium, chloride, and phosphate, but decreased potassium and calcium levels and total nitrogen concentrations in all plant organs independently of the available nitrogen level. However, the effect of salt treatment on magnesium and nitrate concentrations in photosynthetic organs depended on nitrogen levels. Salt treatment reduced photosynthesis rates in LN and HN conditions because of inhibited stomatal conductance. The effects of salinity on leaf NR and GS activities depended on nitrogen levels, with activities increasing in LN conditions. In saline conditions, LN availability resulted in optimal growth because of low chloride accumulation and increases in total nitrogen concentrations, nitrogen use efficiency, and NR and GS activities in photosynthetic organs. Therefore, T. alexandrinum is a legume forage crop that can be cultivated in low-saline soils where nitrogen availability is limited.
- Subjects :
- 0106 biological sciences
0301 basic medicine
Stomatal conductance
Salinity
Soil salinity
Nitrogen
chemistry.chemical_element
Plant Science
Biology
Sodium Chloride
Nitrate reductase
01 natural sciences
Nitrate Reductase
Plant Roots
03 medical and health sciences
chemistry.chemical_compound
Animal science
Nitrate
Glutamate-Ammonia Ligase
Stress, Physiological
Trifolium alexandrinum
Biomass
Photosynthesis
Enzyme Assays
Minerals
Plant Stems
Plant Transpiration
biology.organism_classification
Plant Leaves
030104 developmental biology
chemistry
Agronomy
Plant Stomata
Trifolium
Plant nutrition
010606 plant biology & botany
Subjects
Details
- ISSN :
- 16180860
- Volume :
- 129
- Issue :
- 3
- Database :
- OpenAIRE
- Journal :
- Journal of plant research
- Accession number :
- edsair.doi.dedup.....5d2f8800668f21471b7868a0d9a3382c