曾有人推荐,以一定生长阶段特定叶柄的NO_3—N含量,来评估幼龄番茄植株的N素状况。但对于采样位置,研究者见解不一,有的研究报告更是使用“新近成熟叶”之类的模糊术语。因此,本研究旨在确定NO_3—N含量随叶位变化的程度。 通常,营养诊断指标主要根据全叶样来确定大量和微量元素的含量范围。全叶的N素诊断指标可用全N,但对许多蔬菜作物来说,NO_3—N更能简捷且理想地反映N素状况。然而,蔬菜作物较为详尽的NO_3—N指标系以叶柄,而非全叶。运用最新知识和最先进技术组成的一套有效的组织分析系统,系采用电位分析测定全叶样的NO_3—N,并 It has been recommended to assess the N-status of young tomato plants at a certain stage of petiole NO_3-N content. But for the sampling location, the researchers disagree, and some research report is the use of fuzzy terms such as “newly mature leaves.” Therefore, the purpose of this study was to determine the extent of NO3-N content change with leaf position. In general, nutrition diagnostics are based on whole leaf samples to determine the range of large and trace elements. Whole-leaf N-element diagnostic indicators can be used for all N, but for many vegetable crops, NO_3-N is more concise and ideally reflects the N-status. However, the more detailed NO_3-N indicator of vegetable crops is petiole, not whole leaf. Using an up-to-date knowledge and state-of-the-art technology, an effective set of tissue analysis systems is used to determine leaf-like NO 3 -N by potentiometric analysis