Abstract
: Understanding the interaction between salinity and nitrogen (N) nutrition is of great economic importance to improve plant growth and grain yield for oat plants. The objective of this study was to investigate whether N application could alleviate the negative effect of salinity (NaCl) stress on oat physiological parameters and yield performance. Two oat genotypes with contrasting salt tolerance response (6-SA120097, a salt-tolerant genotype SA and 153-ND121147, salt-sensitive ND) were grown under four N rates (0, 100, 200, and 400 mg N pot−1) in non-saline and saline (100 mM NaCl) conditions. The results showed that salinity, N fertilization and their interaction significantly affected the photosynthetic rate, transpiration rate, agronomic nitrogen use efficiency (aNUE), physiological nitrogen efficiency (pNUE) and apparent nitrogen recovery (ANR), seed number, and grain yield. Saline stress reduced gas exchange rate, nitrogen use efficiency (NUE), grain yield, and yield components. N fertilization increased photosynthetic productivity and chlorophyll fluorescence, resulting in improved grain yields and yield components for both genotypes. On average, the photosynthetic rate was increased by 38.7%, 74.1%, and 98.8% for SA and by 49.8%, 77.6%, and 110% for ND, respectively, under the N rates of 100, 200, and 400 mg N pot−1, as compared with non-fertilized treatment. In addition, grain yield was increased by 80.6% for genotype SA and 88.7% for genotype ND under higher N application rate (200 mg N pot−1) in comparison with the non-nitrogen treatment. Our experimental results showed that an increase of N supply can alleviate the negative effects induced by salinity stress and improved plant growth and yield by maintaining the integrity of the photosynthesis and chlorophyll fluorescence processes of oat plants, which provides a valuable agronomic strategy for improving oat production in salt-affected soils.
Highlights
Saline stress has become one of the major abiotic stresses restricting crop productivity and agricultural sustainability in many areas of the world, especially in arid and semiarid regions [1,2].Agronomy 2019, 9, 115; doi:10.3390/agronomy9030115 www.mdpi.com/journal/agronomyCurrently, more than 20% of the world’s cultivated areas are affected by salinity [3]
We found that the photosynthetic rate, nitrogen use efficiency, plant height, and grain yield were significantly affected by the interaction of salinity stress and N fertilization
Photosynthetic productivity, grain yield, and nitrogen use efficiency of oat plants were considerably affected by salinity, N fertilizer rate, and their interaction
Summary
Saline stress has become one of the major abiotic stresses restricting crop productivity and agricultural sustainability in many areas of the world, especially in arid and semiarid regions [1,2].Agronomy 2019, 9, 115; doi:10.3390/agronomy9030115 www.mdpi.com/journal/agronomyCurrently, more than 20% of the world’s cultivated areas are affected by salinity [3]. It is estimated that more than 34 million hectares of farming lands are affected by salinity in China [4,5]. With population growth and increasing demand for food, large fertile farming lands previously cultivated to oat have been replaced by other high-yielding crops like rice and maize [6]. The increasing saline stress, due to high evapotranspiration and limited rainfall as well as poor soil management, has adversely affected its growth, nutritive value, and yield capacity [7,8]. Alternative cultural techniques are being developed to reduce the adverse effects of salinity on crop growth and production. Proper application of fertilizer is a convenient and effective practice to improve yield and nutritive value for oat plants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
