Abstract Virtually no information exists on the response of sweet corn (Zea mays L. saccharata) to nitrogen fertility and irrigation treatments in terms of leaf nitrogen accumulation and the consequent impact on leaf CO2 assimilation rate and on crop growth as measured as radiation use efficiency (RUE). A two-year field experiment was undertaken in which a sweet corn cultivar was subjected to all combinations of five nitrogen fertility and three irrigation treatments. Leaf photosynthesis measurements were made at stages of 7–9 leaves, tasseling, silking, blistering, and milking. Leaf nitrogen per unit area was also measured at these five stages plus two additional stages before and after the five core measurements. Total nitrogen and plant mass was accumulated at the seven stages to track total nitrogen accumulation and to calculate RUE. The overall patterns in the measured variables were similar to those reported for field maize. However, leaf nitrogen per unit area for sweet corn under optimum conditions was greater than reported for field maize. The higher leaf nitrogen per unit area in sweet corn did not, however, result in greater leaf photosynthesis rates and RUE than reported for field maize. The results of these unique observations on sweet corn indicate the possibility of greater nitrogen storage in sweet corn leaves that is not directly linked with photosynthesis and carbon accumulation.

中文翻译：

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可变氮肥和灌溉条件下甜玉米氮素积累、叶片光合速率和辐射利用效率

摘要 几乎没有关于甜玉米 (Zea mays L. saccharata) 对氮肥力和灌溉处理在叶片氮积累方面的反应以及对叶片 CO2 同化率和作物生长的影响（以辐射利用效率衡量）的信息。后悔）。进行了为期两年的田间试验，其中对甜玉米品种进行了五种氮肥和三种灌溉处理的所有组合。叶片光合作用测量是在 7-9 片叶子、雄花、抽丝、起泡和挤奶的阶段进行的。在这五个阶段加上五个核心测量前后的两个额外阶段，也测量了每单位面积的叶氮。在七个阶段积累总氮和植物质量以跟踪总氮积累并计算 RUE。测量变量的总体模式与田间玉米报告的模式相似。然而，最佳条件下甜玉米的单位面积叶氮高于田间玉米的报道。然而，甜玉米每单位面积较高的叶氮并没有导致比田间玉米报告的更高的叶片光合作用速率和 RUE。这些对甜玉米的独特观察结果表明，甜玉米叶片中可能存在更大的氮储存量，而这与光合作用和碳积累没有直接关系。导致比田间玉米报道的更高的叶片光合作用速率和 RUE。这些对甜玉米的独特观察结果表明，甜玉米叶片中可能存在更大的氮储存量，而这与光合作用和碳积累没有直接关系。导致比田间玉米报道的更高的叶片光合作用速率和 RUE。这些对甜玉米的独特观察结果表明，甜玉米叶片中可能存在更大的氮储存量，而这与光合作用和碳积累没有直接关系。