1954 Volume 22 Issue 3-4 Pages 15-16
l. Tobacco seedlings were grown with nutrient solutions at various levels of nitrogen and phosphorus supplies and the effects of nutrition upon their vegetative characters, their rooting capacity and the subsequent growth were examined. 2. The growth in the plant size was larger at high levels of available N, and P, but under excessive supplies of N and P, the dry weight of the seedling became to drop. In the plot of 40 ppm of N-10ppm of P, the plants showed the best growth. 3. The total nitrogen and phosphorus contents of the seedling plant bodies increased with the amounts of supply of each element, but the totsl carbohydrate was found to be higher with decreasing concentrations of nitrogen at each phosphorus level and its absolute amount per plant was correlated with the dry matter. 4. The rooting capacity was not associated with the carbohydrate percentage of C/N ratio. but was closely connected with the absolute quantity of total carbohydrate per plant. 5. The growth after transplanting was associated directly with the plant size of seedlings and their rooting capacity. The larger the dry weight of the plants, the earlier they reached the stage of flower differentiation or budding, under the experimental conditions. 6. The differences in the amounts of absorbed N and P did not influence the essential natures of development and were observed only to havd contrlloing influences upon the growing speed of the plant to reach the stage to response to certain changes in developing process in connection with vegetative conditions.
