Reduction of nitrates by organs of plants in families of Brassicaceae, Poaceae, Fabaceae

According to the ability to assimilate nitrate all plants are usually divided into three groups, including those with high nitrate reductase activity in plant root, low nitrate reductase activity in plant root and approximately equal nitrate reductase activity in root and leaves.The authors studied the assimilation of nitrates by different organs in plants of Brassicaceae ( Raphanus sativus convar. oleifera, Raphanus sativus loba, Raphanus sativus, garden radish of the Zhara, Saksa, Ledyanaya sosul’ka varieties), Poaceae (spring wheat, winter wheat, barley, maize) and Fabaceae ( Pisum sativum, Soja hispida, Lupinus perennis, garbanzo) in controlled conditions of development. The nitrate reductase activity, the content of nitrates in organs, and also the mass of dump matter were determined in 15-days plants. The most activity of nitrate reductase in all organs was revealed in Raphanus sativus convar. oleifera. This activity was highest in leaves almost in all studied species, which carry out the basic role in process of reduction of nitrates. So grouping the plants on their ability to reduce nitrates did not have clear boundaries. The species differ in this index even within the range of one family.