试验旨在探究玉米叶片不同发育期相关指标的动态变化，为饲料相关研究提供一定的参考依据。本研究以甜糯玉米、甜玉米和糯玉米这三大类型，共计9个品种的玉米为试验材料，深入探究了玉米叶片在4个发育阶段（T1 - T4）的形态指标、叶绿素含量、生物活性物质（类黄酮和总酚）以及抗氧化能力的动态变化情况。研究结果显示，玉米叶片的叶长、叶宽、叶面积和叶片重量等外观形态指标，在T3时期达到最大值，不同品种和类型之间并未表现出明显差异。总叶绿素含量随着叶片发育的推进而逐渐降低，而类黄酮、总酚含量以及抗氧化指标（DPPH、ABTS自由基清除能力和亚铁还原能力）则在T1时期达到峰值，之后随着发育进程呈现出整体下降的趋势。相关性分析表明，叶片的形态指标与生物活性物质及抗氧化指标之间呈负相关关系，这意味着在叶片发育前期，其代谢活性处于较高水平。类黄酮和总酚与抗氧化指标呈极显著（p < 0.01）正相关关系，说明它们具有较强的生物活性。聚类和主成分分析的结果进一步证实，不同品种的玉米叶片指标主要是随着发育时期的变化而变化，品种间的差异并不明显。本研究结果为玉米品种的筛选、亲本的选择以及叶片资源在饲料方面的综合开发利用提供了重要的理论依据。

(Institute of Rural Revitalization Science and Technology,Heilongjiang Academy of Agricultural Sciences,Harbin 150023): The experiment aims to investigate the dynamic changes of relevant indicators of maize leaves at different developmental stages, providing a reference for feed-related research. This study utilized nine maize varieties, including three types: sweet waxy maize, sweet maize, and waxy maize. The morphological indices, chlorophyll content, bioactive substances (flavonoids and total phenols), and antioxidant capacity of leaves were analyzed across four developmental stages (T1–T4). Results showed that morphological indices (leaf length, width, area, and weight) reached their maximum values at T3, with no significant differences observed among varieties or types. Total chlorophyll content gradually decreased with leaf development, whereas flavonoid and total phenol contents, along with antioxidant indices (DPPH radical scavenging capacity, ABTS radical scavenging capacity, and ferrous reduction ability), peaked at T1 and declined thereafter. Correlation analysis