The Effect of Sowing Time and Nutrient Supply on the Yield Stability of Maize75-80Views:110
Sowing time, nutrient supply and plant number play crucial roles in the yield stability of maize. The productivity of various hybrids, each with its own genetic characteristics, was tested for three different sowing times and five different fertilizer doses. The highest yields were achieved at the third sowing time (17. V.), which is unusual, because the second half of the summer was rainy and was favourable for late sowing. The seed moisture content at harvest was higher than the optimal 14-15% at the third sowing time, the hybrids, which have intensive bleeding dynamics, couldn’t reach the lower seed moisture content at harvest of the early sowing. In that case we have to decision whether the plus yield of the third sowing time cover the drying costs.
Some hybrids produced the highest yields by N 120, P2O5 75, K2O 90 kg/ha active agent but the higher fertilizer doses depress the yield. The other part of the hybrids were able to produce high yield by bigger fertilizer doses. On the whole the agro-ecological optimum of the NPK fertilization was N 120-160, P 25-100, K 90-120 kg/ha active agent, but the N 80, P2O5 50, K2O 60 kg/ha fertilizer doses was the most effective.
Productivity and Nutrient Reaction of Maize Hybrids78-83Views:69
Several factors influence the quantity and stability of maize yield, the most important being the nutrient supply, the hybrid and precipitation. In 2004, during the maize growing season the precipitation was more than the 30 year’s average, with 68.3 mm, but the distribution was unfavorable. The experiment was carried out in Debrecen at the Experimental Station of the University of Debrecen Centre of Agricultural Sciences, Department of Crop Production and Applied Ecology. We tested 10 various hybrids with their own genetic characteristics for five different fertilizer doses, in addition to the parcels without fertilization.
The favorable results reached were due to the rainy season. The average yield varied between 7.78-9.67 tha-1. The DK 440, PR37M34, PR38A24, PR39D81 and PR36R10 of the hybrids reacted to higher fertilizer doses with significant growth yields, the yield (more than 11 tha-1) was the highest for N200, P125, K150 fertilizing. The other hybrids, DKC 5211, Mv Vilma and MV Maraton, gave similar results at the N120+PK fertilizer dose and the ensuing doses depressed the yield. Fertilization was more effective thanks to the precipitation. The fourth and fifth dose increased or decreased maize yield depending on the nutrient reaction of the hybrid. The agro-ecological optimum of NPK fertilization was N120, P75, K90 kgha-1.
During the experiment we tested the moisture loss of five hybrids. The rainy crop year’s effect on the seed moisture content at harvest was higher than in previous years. The seed moisture content hybrids at harvest which have shorter crop years (FAO 300) was 18-19%, and hybrids with longer vegetation periods had more than 20% seed moisture content. DK 440 hybrid had the intensive moisture loss of the five hybrids, at the start of the measurement, the seed moisture content was higher than 40%, and it decreased to 18.6% by harvesting.
The effect of season and fertilizer on the LAI, the photosynthesis and the yield of the maize hybrids with different genetic characteristics27-34Views:69
The experiment was carried out in Debrecen, at the Experimental Station of the University of Debrecen Centre of Agricultural Sciences, Department of Crop Production and Applied Ecology. We tested 10 various hybrids with their own genetic characteristics for five different fertilizer doses, in addition to the parcels without fertilization. The three factors of production technology jointly determine the successfully of maize production, but in different measure. The yield and the stability of yield of maize can be increased with hybrid-specific technologies.
In 2004-2005 experiment years the favorable results reached were due to the rainy season. There were significant difference between the productivity of maize hybrids. The N 40, P2O5 25, K2O 30 kg/ha treatment caused the highest increase of yield (3-5 t/ha) compared to the control (parcels without fertilization). The reaction of hybrids to the further fertilizer doses was different. The agro-ecological optimum of NPK fertilization was N 120, P 75, K 90 kg of the most hybrids.
During the experiment, we tested the moisture loss of the five hybrids. The seed moisture content at harvest was higher than in previous years due to the rainy seasons. The seed moisture content of harvest of FAO 200-300 hybrids were about 20%. It changed between 21-24% in the case of hybrids with longer vegetation period (FAO 400), the seed moisture content of Mv Vilma (FAO 510) was 24.21-25.04% in the average of fertilizer treatments. There is an important difference between the moisture loss ability of hybrids which changed 0.2-0.6%/day. The moisture loss of hybrids changed depending on the fertilizer treatment; usually, it was more favorable in the optimal fertilizer dose (N120+PK).
In the case of tested hybrids, we measured the highest LAI and photosynthetic activity at the optimal treatment, N 120, P2O5 75, K2O 90 kg/ha in the respect of efficiency and environmental protection, and the yield was high also for this treatment. There are significant difference between the LAI, the photosynthetic activity and the yield of hybrids, and these values could change depending on the treatment of fertilization.