The Using Of Microelectrode Studying Trans-Membrane Potential And Nitrate Activity In Plant Cell

The ion selective microelectrode is measuring ion activity in a single cell in vivo and its continuous change during external treatment. It is characteristic of continuous measuring, reliable and without cell fraction. Ion activity in different compartmentations of cell can also be measured using ion selective microelectrode. Many reports have been found on the root ion uptake of maize, barley, and soybean, etc. Unfortunately, rice roots can be easily ligilified, thus, there were only a few reports concerning root ion uptake of rice which servers the main food in China. Plant leaf was so thin and easily vabntated that it was hard to matain a steady recording, the using of microelectrode studying ion uptake on plant leaf cell is left as a blank. Hence, the thesis was set out to studying the using of ion selective microelectrode in rice leaf and extends its application in studying nitrate uptake and utilization in rice root.Firstly, ion selective microelectrode and its application in nitrate uptake were firstly introduced in China. The protocol of manipulation was described in detail after practice of several times, including the construction of electrophysiology lab, making of single and double barreled selective microelectrode, working theory and notice.The microelectrode was turn out to be characterized by a high selectivity and sensitivity of ion and a good economy compared with other intracellular measurement. In addition, the in vivo method is better than the chemical analysis of the samples. The detected results showed that nitrate activity in leaf cell of Chinese cabbage induced with 5 mmol·L^-1 nitrate for 48h fell into two different populations, i.e.0.24 mmol·L^-1-10 mmol·L^-1 in cytosol and 20 mmol·L^-1-110 mmol·L^-1 in vacuole. Since vacuolar volume accounts for 90% of a whole cell, most of the nitrate in plants is stored in vacuoles. And, thus it is of great importance to study the remobilization of the nitrate in vacuoles both in increasing nitrogen use efficiency and in decreasing the nitrate content the vegetable. Then, the uptake of nitrate (NO₃^- by roots of rice seedlings (yangdao 6) at different pHs...