Nitrogen deficiency induced a decrease in grain yield related to photosynthetic characteristics, carbon–nitrogen balance and nitrogen use efficiency in proso millet (Panicum miliaceum L.). Issue 3 (23rd February 2020)

• Record Type: Journal Article
• Authors: Gong, Xiangwei; Li, Jing; Ma, Hongchi; Chen, Guanghua; Dang, Ke; Yang, Pu; Wang, Meng; Feng, Baili
• Is Part Of: Archives of agronomy and soil science. Volume 66:Issue 3(2020)
• Page Start: 398
• Page End: 413
• Publication Date: 2020-02-23
• Subjects: Carbon–nitrogen balance -- grain yield -- nitrogen deficiency -- photosynthetic characteristics -- proso millet; Horticulture -- Periodicals; Soils -- Periodicals; 630.5
• DOI: 10.1080/03650340.2019.1619077
• Languages: English
• ISSNs: 0365-0340

Abstract

ABSTRACT: Field experiments involving proso millet ( Panicum miliaceum L.) cultivar under four nitrogen (N) levels (N0, N60, N105 and N150) were conducted in 2015 and 2016 to explore the decrease in grain yield under N deficiency related to the changes in leaf photosynthetic characteristics, carbon (C)–N balance and N use efficiency. Results showed that N deficiency decreased the net photosynthesis rate, stomatal conductance, transpiration rate and chlorophyll content and increased the intercellular CO2 concentration of proso millet flag leaves from flowering to maturity. N deficiency negatively regulated the C–N balance and increased the C/N ratio by reducing the total N, soluble protein and soluble sugar contents, resulting in high starch content. N uptake and utilisation were significantly reduced because of less available N. Significantly positive correlations were observed between the grain yield and photosynthetic characteristics or N use efficiency, whereas a negative correlation was found between the grain yield and the C/N ratio. The yields generated by N0, N60 and N105 were lower than that of N150 in both years. The N fertiliser regression formulae developed in the study would provide useful information about the N fertiliser rate of proso millet.