蔬菜不同器官的硝态氮与水分、全氮、全磷的关系

在亩施12kg氮素的肥沃菜园红油土上分别种植菠菜、小白菜和莴笋等3种蔬菜,并于翌年3月施肥10天后分3次采样测定不同器官的硝态氮和水分、全氮、全磷含量,研究硝态氮分布与后三者之间的关系。结果表明,3种蔬菜的硝态氮含量因器官而异,根、茎和叶柄的的含量最高(557.8～1196.7g/g,鲜重),外围叶片次之(213.5～551.8g/g,鲜重),心叶叶片最低(120.6～198.3g/g,鲜重)。蔬菜各器官的水分、全氮和全磷含量存在明显差异。茎、叶柄、外围和心叶叶片的硝态氮含量与其中的水分含量呈显著正相关(r=0.910～0.956),与其中的全氮、全磷含量呈显著负相关(r=-0.733～-0.951)。根系与这一趋势不符。

RELATIONSHIPS BETWEEN NITRATE CONTENTS AND WATER, TOTAL N AS WELL AS TOTAL P IN DIFFERENT ORGANS OF VEGETABLE PLANTS

Spinach, Chinese cabbage and lettuce were planted in a Hongyou soil located in the vegetable garden of the university, and the plants were sampled 3 times after 10 days of N fertilization for determination of nitrate, water, total N and total P to study the nitrate distribution relationships to the later three components. The results showed that the nitrate contents were different with different organs, the roots, stems and Petioles being the highest in nitrate contents (557. 9~ 1196.7ug per gram fresh weight) followed by outside blades (213. 5~551. 8ug per gram fresh weight) and central blades being the lowest (120. 6-198. 3ug per gram fresh weight). Also, water, total N and total P contents in different organs were obviously different. The nitrate contents were positively correlated with water contents in stems, petioles, outside and central blades, the correlation coefficients ranging from 0.910 to 0.956, but negatively correlated with the amounts of total N and total P, the correlation coefficients ranging from - 0.733 to -0.951. In contrast, the nitrate contents in roots were not in accordance with these patterns.