Effects of irrigation and nitrogen on growth and water productivity of maize grown in saline soil

ABSTRACT

A two-year field experiment was conducted to evaluate the effect of irrigation and nitrogen amount on maize growth and water productivity for saline soil. The main treatments were four nitrogen levels 0 (N0), 215 (N1), 270 (N2), and 325 kg ha⁻¹ (N3) and three irrigation levels 500 (W1), 400 (W2), and 300 mm (W3). The results demonstrated that all treatments were in salt leaching state in 2016 and in salt accumulation state in 2017. Soil salinity decreased with increasing nitrogen amount while nitrogen amount was lower than 270 kg ha⁻¹ under W2, but increased with increasing nitrogen amount under W3. Compared with W1N2, the reduction in plant height and leaf area index of W2N2 was less than 7.0%. The total water consumption decreased with decreasing irrigation and nitrogen amount. Yield of W2N2 was only 5.0% less than W1N2 in 2016, but obtained the largest yield in 2017. Yield and water use efficiency were elevated while nitrogen amount increased from 0 to 270 kg ha⁻¹, but were decreased while nitrogen amount exceeded 270 kg ha⁻¹. Thus, irrigation amount 400 mm in combined with nitrogen amount 270 kg ha⁻¹ could alleviate salt accumulation, promote maize growth, and ensure maize yield.

KEYWORDS:

• Saline soil
• yield
• irrigation amount
• soil salinity
• water use efficiency

Acknowledgements

We thank the anonymous reviewers and editors for their constructive comments on this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was funded by the financial support from the Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources (grant no. 2019001), the Natural Science Foundation of Shanxi Province of China (grant no. 201901D211101), and Scientific and technological innovation project of excellent talents of Shanxi Province (grant no. 201805D211017).