The effect of density and nitrogen fertilizer on the growth and yield of maize (Zea maysL.) in Nigeria

Abstract

SummarFARZ 27, a high-yield maize variety, was grown in 1984 and 1985 over a wide range of density treatments (1·9– 11·1 plants/m2) and with four rates of nitrogen application (0, 75, 100 and 150 kg N/ha) in Ibadan. south-western Nigeria.There was no significant density or fertilizer effect on morphological characters of number of leaves per plant, height or stem diameter. For total dry-matter yield, the highest density of planting gave the highest yield although less dry matter was obtained in the 1985 experiment than in the 1984 experiment. Optimum density for grain production in both years was 8·8 plants/m2. There is an indication that there is no need to increase density of planting of maize beyond 80000 plants/ha in the south-western part of Nigeria. Plants without applied nitrogen fertilizer gave significantly lower total dry-matter and grain yields than plants with applied nitrogen. Highest grain yield was obtained with 150 kg N/ha in both years. By doubling the nitrogen application rate from the present recommended level of 75 kg N/ha to 150 kg N/ha an average increase of 0·42t/ha of maize was obtained in both years. With the present prices of fertilizer and maize, this increase is economical. It seems therefore that more revenue would accrue to the farmers by using 150 kg N/ha on the ‘FARZ series’ of maize instead of the present recommendation of 75 kg N/ha.