INFLUENCE OF NITRATE SUPPLY UPON THE ASCORBIC ACID CONTENT OF TOMATOES
INFLUENCE OF NITRATE SUPPLY UPON THE ASCORBIC ACID CONTENT OF TOMATOES
复制标题
硝酸盐供应对番茄抗坏血酸含量的影响
DOI：
10.1002/j.1537-2197.1951.tb14849.x
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发表时间：
1951
影响因子：
3
通讯作者：
K. C. Hamner
中科院分区：
文献类型：
--
作者：
G. Somers;W. C. Kelly;K. C. Hamner
据报道，施用氮肥会降低各种作物的抗坏血酸含量（Hamner 和 Maynard，1942 年；Maynard 和 Beeson，1943-44 年；Somers 和 Beeson，1948 年，综述；Jones 和 Parker，1947 年）。Hamner 等人（1945 年）报告说，施用大量氮肥（2020-10）的田块中，西红柿的抗坏血酸含量比施用不含氮肥料（0-20-10）的同类田块中的抗坏血酸含量低 20%。然而，在沙地栽培中，Hamner 等人（1942 年）没有发现氮的供应对番茄抗坏血酸含量有任何影响。Somers 和 Beeson（1948 年）还举出了施氮量对植物抗坏血酸含量影响不大的其他例子。在某些情况下，这些不同的研究结果可能是由所使用的氮源造成的。在合适的条件下，硝态氮和铵态氮对植物组织中抗坏血酸含量的影响可能完全不同（Sideris 和 Young，1945 年；Somers 和 Kelly，1950 年）。下面的实验旨在更详细地研究供应给番茄植株的氮量对成熟番茄抗坏血酸含量影响的生理基础。番茄种子（品种 Bonny Best）于 1945 年 4 月 7 日种在沙地上，随后用 1:5 稀释的霍格兰 1 号溶液（霍格兰和阿农，1938 年）浇灌 1 周。除表 1 所示情况外，在实验的其余时间里，植物都是用全浓度的霍格兰溶液浇灌的。5 月 6 日，植物被移植到 2 加仑的沙罐中，每天用霍格兰溶液浇灌一次，每周用蒸馏水冲洗一次。所有植物都在温室中生长，直到 6 月 21 日才移到室外，并绑在高桩上。通过经常摘除侧芽，将它们修剪成单茎。移到室外后，植物被分成两个区块，每个区块有 36 株植物。每个区块有六种处理，每种处理有六株植物，植物之间的间距使它们相互遮蔽的程度很低。在实验过程中，不同处理在不同时期向植物提供的硝酸盐量各不相同。表 1 对这些处理进行了总结。使用全浓度的 Hoagland 溶液获得的硝酸盐供应量最大，为 15 me./l。较低的硝酸盐供应率
THE APPLICATION of nitrogen fertilizer has been reported to lower the ascorbic acid content of various crops (Hamner and Maynard, 1942; Maynard and Beeson, 1943-44; Somers and Beeson, 1948, for reviews; also Jones and Parker, 1947). Hamner et al. (1945) reported that the ascorbic acid content of tomatoes from field plots which received fertilizer containing large amounts of nitrogen (2020-10) was about 20 per cent less than from comparable plots which received a fertilizer containing no nitrogen (0-20-10) at the same rate. In sand culture, however, Hamner et al. (1942) failed to find any effect of nitrogen supply upon the ascorbic acid content of tomatoes. Other instances where the amount of nitrogen applied failed to influence significantly the ascorbic acid content of plants are cited by Somers and Beeson (1948). In some cases these different findings may result from the nitrogen source used. Nitrate and ammonium sources of nitrogen supply under suitable conditions may have quite different effects upon the ascorbic acid content of plant tissues (Sideris and Young, 1945; Somers and Kelly, 1950). The following experiment was undertaken to study in more detail the physiological basis for the influence of the amount of nitrogen supplied to tomato plants upon the ascorbic acid content of the ripe tomatoes produced. MATERIALS AND METHODS.-Tomato seed (variety Bonny Best) was planted in sand April 7, 1945, and was watered for 1 week subsequently with Hoagland Solution No. 1 diluted 1:5 (Hoagland and Arnon, 1938). Throughout the rest of the experiment the plants were watered with full strength Hoagland solution except as indicated in table 1. The plants were transplanted to 2 gal. crocks of sand May 6, where they were watered once a day with Hoagland solution and flushed once a week with distilled water. All of the plants were allowed to grow in the greenhouse until June 21, when they were moved outside and were tied to tall stakes. They were pruned to a single stem by frequent removal of the lateral buds. Upon being moved outside the plants were arranged in two blocks of thirty-six plants each. Each block contained six treatments with six plants in each, and the plants were spaced so that they shaded each other very little, if any. The various treatments differed from each other in the amount of nitrate which was supplied to the plants at various periods during the experiment. They are summarized in table 1. The greatest nitrate supply, 15 me./l., was that obtained by using full strength Hoagland solution. The lower rates of nitrate suip-