水中施肥に関する研究-I

Abstract

The manure effects of four N-compounds, NH4NO3, NaNO3, NaNO2, and CO (NH2)2, for Gelidium amansii which was cultured in the sea water added various quantities of these compounds (2, 5, 10 ppm in N-content) were comparatively examined. 1. Maximum increases in the contents of total-N and protein-N were found in the plants cultured in the sea water containing 5 ppm as NH4NO3-N. Now it is judged by the writer that NH4NO3 is the best as the manure of Gelidium amansii. The plants, however, were injured in the sea water containing more than 10 ppm as NH4NO3-N. 2. Since some increases in two forms of nitrogen of the plants were found by the addition of NaNO3 to culture sea water, this N-compound may be effective as the manure. 3. Since NaNO2 was hardly absorbed into the plants or even if it was absorbed it did not reduce in the plants, it is not effective as the manure. 4. CO(NH2)2 gave some effect to the nitrogen contents, and the plants were injured in the sea water containing 10 ppm as CO (NH2)2-N.