The development of chernozem soil water management and its relationship with maize yields was studied in a 30-years long-term field experiment with different crop-rotation systems (mono-, bi- and triculture), in three crop years with different natural precipitation: a drought (2007), a wet (2008) and a dry (2009 one. The relevant soil layer was... divided to three sub-layers: (0–60 cm, 61–120 cm, 121–200 cm) in which the development of soil moisture content was investigated during the whole vegetation. From the results it can be stated that change of the water stock of the upper soil layer (0–60 cm) was the most intensive. Both the direct effect of natural precipitation and irrigation could be observed in the most obvious way in it. Yield result of maize and the highest water supply deficit values in the vegetation were compared in our work too. According to the results it was revealed that among the three studied crop rotation systems it was the monoculture, the success of production of which depends the most of water supply. The most favourable crop rotation system was the triculture from both the aspect of the yield of produced crops and the favourable soil properties too.
The effect of increasing fertilizer dosages on the yield of eight different maize hybrids (SY Ondina, NK Kansas, NK Lucius, NK Octet, NK Thermo, SY Flovita, SY Brillio, NX 47279) has been investigated in the crop-year of 2011. According to our results it can be stated that contrarily to the control treatment the application of different nutrien...t-levels has resulted a significant yield increment (2 000–5 800 kg ha-1).
Based upon the results of this experiment we have drawn the conclusion that the nutrient level of 120 kg N+PK was the optimal for the investigated hybrids. The highest yield (14 475 kg ha-1–15 963 kg ha-1) of the hybrids with different genotypes has been produced in case of this fertilizer treatment. With the comparison of the control and the optimum-fertilizer treatments the yield-increasing effect of mineral fertilization and the different reaction of hybrids towards increasing fertilizer dosages have been proven. In case of the control treatments the best-yielding hybrids were NK Thermo (11 917 kg ha-1) and NX 47279 (11 617 kg ha-1). Contrarily on the optimal nutrient supply level the hybrids SY Brillio (15 876 kg ha-1) and NX 47279 (15 963 kg ha-1) have produced the highest yields. Summarizing, we can state that the hybrid NX 47279 has resulted stable and high yields in the fertilized treatments. Analysing the yield-increasing effect of 1 kg fertilizer active substance it was proven, that the hybrids SY Flovita (45.43 kg ha-1), SY Brillio (44.47 kg ha-1) and NX 47279 (42.33 kg ha-1) had a good reaction towards even lower nutrient supply levels as well. In case of the control treatment the average water utilization coefficient of the hybrids was significantly lower (35.2 kg mm-1), than in case of the optimal nutrient supply level (N120+PK) treatments (48.9 kg mm-1).
Therefore the hybrid specific difference between the water utilization of genotypes could be revealed.
We examined the change of the time of water balance of soil in 25 years old experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture) in dry (2007) and rainy (2008) cropyear in maizestock. According to our findings the values of waterdeficit of soil of maizestock were much smaller in 2008 than values of last y...ear in not irrigated and irrigated plots of three of crop-rotation systems because of favourable supply of precipitation. We found difference between values of waterdeficit of two irrigation treatments. We measured smaller values in irrigated plots of three of crop-rotation systems before sowing. Waterstock of soil started to decrease with the rising of average temperature and despite of increasing of precipitation quantity in this way we calculated higher values of waterdeficit. Precipitation in August and high average temperature intensified the waterdeficit. Waterdeficit achieved highest values of croptime to front of September. We examined waterbalance of soilprofile in 0-200 cm and we concluded that the waterdeficit of the 80-120 cm soilzone was most intensiv in not irrigated and irrigated treatments because of significant rootmass.
Maize plant response to plant density is an essential agrotechnical factor used for determining grain yield. Three plant densities (60,000 ha-1, 72,500 ha-1, and 85,000 ha-1) were used in this study to ascertain the effect of photosynthetic parameters and grain yield. Results show a significant difference in the... photosynthetic parameters (SPAD, NDVI, LAI) and plant height for plant density of 85,000 ha-1. Grain yield and stem diameter were not significantly affected between the different plant densities.
We examined the change of the time of water balance of soil in 25 years old experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture) in two extreme cropyear in 2007 and 2009 in maizestock.
According to our findings the values of waterdeficit of soil of maizestock were about 100 mm before the sowing time th
We examined the change of the time of water balance of soil in long-term experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture). We found the smallest difference between the water deficit of not irrigated and irrigated plots in triculture. We concluded that irrigation impressed favourably on water balance o...f soil in both of crop-rotation systems. Water deficit has decreased significantly after irrigation
in 25. May in mono- and triculture. Irrigation moderated only values of water deficit. Irrigation in 30. June not influenced water balance of soil in both of crop-rotation because of a big drought. Water deficit of soil lessed till harvestperiod because of rainy season at the end of August and in September.
Extreme weather conditions are becoming more and more frequent in the crop years, thus increase the risk of sunflower production.
The objective of researches into plant production is to minimize these effects as much as possible. In this sense, the optimization of
agrotechnological factors is of high importance. Within these factors, the
and optimized, rational crop protection technologies are important, especially in the highly sensitive sunflower cultures. The effect of
sowing time, crop density, and fungicide treatments on the yield of sunflower hybrids was analysed in different crop years in 2008
and 2009. In each case, the infection was highest with the early sowing time and at the highest crop density level (65000 ha-1). When
one fungicide treatment was applied, the rate of infection decreased compared to the control treatment. The further decrease of the
infection rate was less after the second fungicide treatment.
In the humid year of 2008 the crop yield was the highest at 45000 ha-1 crop density level in the control treatment and at 55000 crop
ha-1 crop density level when fungicides were applied. In the draughty year of 2009 the maximum yield was gained at 55000 ha-1 crop
density level in the control treatment and at 65000 crop ha-1 when fungicides were applied. In 2008 and 2009 as regards the crop
yield, the difference between the optimal and minimal crop density levels was higher in the fungicide treatments than in the control
treatment (in 2008: control: 517 kg ha-1; one application of fungicides: 865 kg ha-1; two applications of fungicides: 842 kg ha-1), (in
2009: control: 577 kg ha-1; one application of fungicides: 761 kg ha-1; two applications of fungicides: 905 kg ha-1).
In each and every case, the first treatment with fungicides was more effective than the second. In 2008, the highest yield was
obtained with the third, late sowing time in each fungicide treatment. The differences between the crop yields with different sowing
times was less than in 2009, when the results of the second treatment exceeded those of the first and third treatment in each case.