Abstract
Nitrogenous nutrient is one of the major element to regulate plant growth, however little is known on the plant hormones relationships in the mechanisms of growth regulation with nitrogenous nutrient. Present experiment was conducted to study ethylene relationships in the regulatory mechanism of nitrogenous nutrient in the growth of rice plant. Growth rate, nitrogen content and ethylene evolution in leaves under different nitrogen levels were examined. The results obtained were as follows. 1. The higher the content of nitrogen in leaves and the greater the plant growth, the less was the ethylene evolution in rice leaves. 2. Very clear positive correlation was found between the nitrogen content in the leaves and the growth rate, while high negative correlation was detected between nitrogen content in leaves and ethylene evolution from leaves. 3. Therefore, a fairly close negative correlations were observed between the ethylene evolution from leaves and the rate of growth. Based on those results, it seems probable that the reduced ethylene evolution from leaves under high nitrogen condition may play an important role to explain growth promotion by nitrogen supply in plant.
