Leaf area and its longevity are the key factors driving dry matter accumulation and yield formation in maize (Zea mays. L). Both factors are influenced by cultivation management measures. The objective of this study was to utilize a quantitative framework to better understand the contribution of leaf area and longevity to leaf area duration (LAD) and yield in maize plants at varying plant densities and nitrogen application rates. A two-year field experiment was conducted using a factorial combination of two plant densities and four nitrogen levels. Leaf area and longevity were measured at each leaf position in two different maize cultivars. We calculated the LAD at the single-leaf, individual-plant, and whole-population scales and quantitatively analyzed the contribution of leaf area and longevity to LAD. The results showed that in the upper leaves, leaf area had a larger proportional contribution to LAD (54.1–95.7%), whereas in the lower leaves, leaf longevity contributed more to LAD (51.8–74.1%). Both were greatly affected by variations in plant density and nitrogen application. At the individual-plant scale, the proportional contribution of leaf area to LAD (57.3%) was similar to that of leaf longevity (57.2%); at the whole-population scale, leaf area accounted for a larger contribution to LAD (87.0%). The increase in LAD (which integrating increases in leaf area and longevity) was positively associated with an increase in dry matter at maturity and grain yield. Yield gain was achieved by reasonable increases in density and nitrogen fertilizer application to promote LAD. The quantitative evaluation of leaf area and longevity described in this study provides a theoretical basis for increasing maize yield under increased plant density and nitrogen input conditions.

叶面积及其寿命是驱动玉米干物质积累和产量形成的关键因素。L)。这两个因素都受到栽培管理措施的影响。本研究的目的是利用定量框架来更好地了解不同植物密度和施氮率下玉米植物叶面积和寿命对叶面积持续时间 (LAD) 和产量的贡献。使用两种植物密度和四种氮水平的因子组合进行了为期两年的田间试验。在两个不同玉米品种的每个叶片位置测量叶面积和寿命。我们在单叶、单株和全种群尺度上计算了 LAD，并定量分析了叶面积和寿命对 LAD 的贡献。结果表明，在上部叶片中，叶面积对 LAD 的比例贡献较大（54.1-95.7%），而在下部叶片中，叶片寿命对 LAD 的贡献更大（51.8-74.1%）。两者都受到植物密度和施氮量变化的极大影响。在单株尺度上，叶面积对 LAD 的比例贡献（57.3%）与叶寿命（57.2%）相似；在全种群尺度上，叶面积对LAD的贡献较大（87.0%）。LAD 的增加（整合了叶面积和寿命的增加）与成熟期干物质和谷物产量的增加呈正相关。通过合理增加密度和施用氮肥来促进 LAD，实现了增产。本研究中描述的叶面积和寿命的定量评估为在增加的植物密度和氮输入条件下增加玉米产量提供了理论基础。