Author : Chanai Yodpetch

Summary : optimum rate of fertilizer and plant population for maximum yield. The nutritional composition of young cob corn was similar in amount and kind with some non-legume vegetables. It was best harvested at two days after silking for canning and three days for local consumption. The Golden Cross Bantam and Super Sweet varieties were found to be promising in terms of earliness, high yield, number of ears/plant, high cob-husk ratio, high harvest index, shortness, good quality, and high enzyme nitrate reductase. Different plant Super Sweet required different optimum rates of fertilizer for maximum yield. For plants grown at population of 60,000 plants/ha the optimum rate was 195 kg/ha; at 120,000 plants/ha, 186 kg N/ha; and 180,000 plants/ha, 192 kg N/ha. Increased rates of nitrogen application and plant population significantly affected agronomic characteristics, nitrate reductase activity, and yield and its components, compared with the control. Increased rates of nitrogen application coupled with high population density tremendously increased yield/ha. Enzyme nitrate reductase in corn leaf increased with increased nitrogen application but decreased with increased plant population.