Plastic response of leaf traits to N deficiency in field-grown maize

• Published in: AoB plants Vol. 14; no. 6; p. plac053
• Main Authors: Fan, Panpan, Ming, Bo, Anten, Niels P R, Evers, Jochem B, Li, Yaoyao, Li, Shaokun, Xie, Ruizhi
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 01.11.2022
• Subjects: Agriculture; Agronomy; Canopies; Corn; Crop production; Efficiency; Fertilization; Fertilizers; Hybrids; Leaf area; Leaves; Light; Nitrogen; Photosynthesis; Plants (botany); Radiation; Studies; Tradeoffs; N management practices; N deficiency; specific leaf area; leaf N content per unit leaf area; Leaf area; maize strategy
• ISSN: 2041-2851; 2041-2851
• DOI: 10.1093/aobpla/plac053

Abstract Nitrogen (N) utilization for crop production under N deficiency conditions is subject to a trade-off between maintaining specific leaf N content (SLN) important for radiation-use efficiency versus maintaining leaf area (LA) development, important for light capture. This paper aims to explore how maize deals with this trade-off through responses in SLN, LA and their underlying traits during the vegetative and reproductive growth stages. In a 10-year N fertilization trial in Jilin province, Northeast China, three N fertilizer levels have been maintained: N deficiency (N0), low N supply (N1) and high N supply (N2). We analysed data from years 8 and 10 of this experiment for two common hybrids. Under N deficiency, maize plants maintained LA and decreased SLN during vegetative stages, while both LA and SLN decreased comparably during reproductive stages. Canopy SLA (specific leaf area, cm2 g–1) decreased sharply during vegetative stages and slightly during reproductive stages, mainly because senesced leaves in the lower canopy had a higher SLA. In the vegetative stage, maize maintained LA at low N by maintaining leaf biomass (albeit hence having N content/mass) and slightly increasing SLA. These responses to N deficiency were stronger in maize hybrid XY335 than in ZD958. We conclude that the main strategy of maize to cope with low N is to maintain LA, mainly by increasing SLA throughout the plant but only during the vegetative growth phase. How do maize plants adapt to external N deficiency conditions? The study was conducted in long-term N-fertilized field experiments and concluded that maize’s main strategy to cope with low N is to maintain leaf area, mainly by increasing specific leaf area (SLA) throughout the plant but only during the vegetative growth phase. The temporal and spatial distribution of SLA is also discussed in this study.