In a long-term maize monoculture experiment set up on the active ingredient equivalence principle, changes in the yield components were investigated over a period of three years (2005–2007) as a function of the fertiliser treatments, and the values of the growth parameters HI, LAI, NAR and CGR were calculated using the classical method of growth analysis.The results indicated that optimum N supplies and the year effect made a substantial contribution both to the grain number per ear and to the thousand-kernel weight. In the course of correlation analysis, both Pearson’s correlation coefficient and multiple regression analysis demonstrated that the grain yield was in close positive correlation with these yield components, and with the maximum value of dry matter production and the harvest index. The two yield components explained 76% of the grain yield, and the effect of thousand-kernel weight was around 3.75 times as great as that of the grain number per ear (β = 0.721 vs. 0.192). On the basis of partial correlation analysis, the maximum value of total dry matter and the thousand-kernel weight were jointly responsible for around 60% of the variance in maize grain yield. Analysis using the “Enter” method showed that the two yield components explained 62% and 59% of the grain yield in wet years (R22005 = 62.3%; R22006 = 58.8%), while in the dry year neither the thousand-kernel weight nor the grain number per ear had a significant effect on the yield (R22007 = 4.5%).
Nowadays, studying the impact of climate change on agricultural crops is of great importance in national and international projects. Research on the effects of climate change on agricultural cultivars is supported by crop growth models. Simulations provide facilities for the low cost investigation of the effects of many factors, both independently of each other and in combination. These models require parameterisation and testing, which can be done using data measurements. In order to test the correctness of the simulations of meteorological and nutrient supply effects, it is necessary to use the results of long-term field experiments with many replicates.In the present study, the Ceres Wheat and AFRCWHEAT2 winter wheat crop growth models were tested, utilizing the data of a five-year sowing date experiment and the relevant meteorological data. An analysis was made of whether changes in the sowing date were able to influence or eliminate the negative effects of the changing climate. It was found that choosing the optimum sowing date could be the key to adapting to changing conditions.
Authors:T. Árendás, P. Bónis, P. Csathó, D. Molnár, and Z. Berzsenyi
The N, P and K effects of mineral fertilisers were examined in a long-term fertilisation experiment set up on chernozem soil with forest residues. The data from 20 experiments on winter wheat and 24 on maize were evaluated as a function of the year, the forecrop and the soil nutrient supplies.Of the two plant species, N effects were found to be greater for winter wheat. When sown after maize, the N responses of both wheat and maize were almost 1 t ha
greater than when winter wheat was the forecrop. The positive effect of phosphorus was only significant in winter wheat, while that of potassium was not significant for either species.In a wheat-wheat sequence, N fertiliser alone was only effective in wet years. In winter wheat, no phosphorus effects could be detected in any year without N fertilisation. In years with extreme weather conditions, P effects were only significant when wheat was grown after cereals.In dry years nitrogen only had a significant effect on the yield of maize after wheat if it was combined with phosphorus and potassium. In years with average or above-average rainfall maize was able to extract sufficient phosphorus for its development even from soils with poor P supplies; yield increases were limited by other factors.
Authors:Z. Berzsenyi, P. Solymosi, T. Árendás, and P. Bónis
The weed mass (g m
) recorded in the first 15 years (1965–1979) of a long-term, bifactorial, split-plot herbicide experiment (main plots: two types of soil cultivation, subplots: 7 herbicide treatments, with two control plots) without crops indicated that the best weed control was achieved with 10 kg ha
rates of simazine and atrazine. These were followed by 5 kg ha
ametryn, 10 kg ha
linuron and 2+2 kg ha
2,4-D, all with moderate efficiency, while 5 kg ha
prometryn and 10 kg ha
monolinuron resulted in poorer weed control. Medium deep ploughing once a year in autumn reduced the weed mass by 36.5%. There was a substantial year effect, well illustrated by the annual changes in weed mass both in the herbicide treatments and in the control plots. In plots treated with simazine and atrazine there was an exponential increase in the weed mass from the 17
year of the experiment, suggesting the multiplication of weed biotypes resistant to triazine. As a result of some herbicide treatments there was a shift in the monocot-dicot ratio.
Authors:G. Micskei, I. Jócsák, T. Árendás, P. Bónis, and Z. Berzsenyi
In a long-term experiment on continuous maize set up by Béla Győrffy in 1959, changes in biotic and abiotic environmental factors were studied over time. The long-term effects and stability of the cropping systems, the year effects and the genotype × environment interactions were analysed. The original aim of the experiment was to determine whether the NPK nutrients in farmyard manure could be replaced partially or entirely by inorganic NPK fertiliser. In the present experiment the effect of farmyard manure, mineral fertiliser and the year effect on yield and yield stability were studied for four years (2005–2008). Various levels of farmyard manure and mineral fertiliser induced significant changes in the yield, harvest index, thousand-kernel mass, grain number per ear and grain protein content.
Authors:Z. Berzsenyi, T. Árendás, P. Bónis, G. Micskei, and E. Sugár
The effects of five crop production factors (tillage, fertilisation, plant density, variety, weed control) on the yield and yield stability of maize were examined in Martonvásár (HU) in a polyfactorial experiment and in separate long-term experiments on the effects of Nfertilisation, sowing date and plant density. In the polyfactorial experiment the five crop production factors contributed to the increase in maize yield in the following ratios (%): fertilisation 30.6, variety 32.6, plant density 20.2, weed control 14.2, soil cultivation 2.4. In the N fertilisation, sowing date and plant density experiments the effects of the treatments on the maize yield were examined separately for dry and wet years.Averaged over 40 years, the yields in the long-term N fertilisation experiment were 2.422 t ha−1 lower in the dry years than in the wet years (5.170 vs. 7.592 t ha−1). The optimum N rate was 160 kg ha−1. In the sowing date experiment the yield was 2.533 t ha−1 lower in the dry years than in the wet years (6.54 vs. 9.093 t ha−1), averaged over 19 years. In dry years the yield was highest for the early and optimum sowing dates, and in wet years for the optimum sowing date. Sowing at dates other than the optimum caused reductions in N fertiliser efficiency. Averaged over 22 years, the optimum plant density was 80,000 plants ha−1 in wet years and 50,000 plants ha−1 in dry years. The yield was most stable at a plant density of 60,000 plants ha−1. The clarification of year effects is particularly important in relation to the possible effects of climate change.
Authors:Z. Berzsenyi, T. Árendás, P. Bónis, G. Micskei, and E. Sugár
The effect of mineral fertilisation, farmyard manure and their combinations on the yield and yield stability of maize was studied in a long-term maize monoculture experiment set up in Martonvásár, Hungary in 1959. The experiment, laid out as a Latin square, included two fertilisation levels [35 t ha−1 or 70 t ha−1 farmyard manure (FYM) every four years] and seven treatments. The yield results were evaluated using analysis of variance, cumulative yield analysis and stability analysis. The year effect was analysed by dividing the 51 years (1959–2009) into wet (32) and dry (19) years. The rainfall sum for the months Apr.–Sep. averaged 361 mm in the wet years and 232 mm in the dry years.Among the fertiliser treatments the FYM + mineral fertiliser combination and NPK mineral fertilisation alone gave the highest yields. In more than 50% of the years the higher fertiliser level had no significant yield-increasing effect. The yield differences between the two fertiliser levels were twice as high in wet years as in dry years (0.543 vs. 0.274). Averaged over all seven treatments, the maize yield was 3.959 t ha−1 in dry years and 6.250 t ha−1 in wet years, giving a yield increment of 2.291 t ha−1 in favourable years. Yield stability was greatest when the NPK content of 35 t ha−1 FYM was replaced in part (17.5 t ha−1 FYM + N1/2P1/2K1/2) or in full (N1P1K1) by mineral fertiliser, or when 70 t ha−1 FYM was applied. Yield stability is an important indicator of the sustainability of crop production.
Authors:T. Árendás, L. C. Marton, P. Bónis, and Z. Berzsenyi
The effect of varying weather conditions on the moisture content of the
maize grain yield was investigated in Martonvásár, Hungary from late August to
late September, and from the 3rd third of September to the 1st third of
Novemberbetween 1999 and 2002. In every year a close positive
correlation (P=0.1%) could be observed between the moisture content in late
September and the rate of drying down in October. Linear regression was used
each year to determine the equilibrium moisture content, to which the moisture
content of kernels returned if they contained less than this quantity of water
in late September and harvesting was delayed. In the experimental years this
value ranged from 15.24-19.01%.
Authors:P. Bónis, T. Árendás, C. L. Marton, and Z. Berzsenyi
A comparison was made of herbicide tolerance results for two years, one
dry (2003) and one wet (2004). The maximum permitted dose and twice this rate
of the herbicides (mesotrione,
mesotrione + atrazine, nicosulfuron, rimsulfuron) were sprayed on inbred maize
lines in the 7-8-leaf stage. The effect of the herbicides on 20 inbred lines
was evaluated on the basis of visible phytotoxic symptoms. In the dry year the
greatest damage, averaged over the inbred lines, was caused by the double rate
of rimsulfuron and nicosulfuron, but the plants had overcome this
by the end of the vegetation period. In 2004 the cool wet spring weather
retarded the metabolic processes of maize, leading to greater phytotoxic
damage. The most severe symptoms were observed for the double rate of mesotrione
+atrazine. The phytotoxic damage caused by the “normal” rates
applied in commercial maize production was overcome by the lines in the wet
year, too. Despite the initial visible phytotoxic damage, none of the herbicides
caused significant differences in grain yield between the control and the
single or double rates of treatment.
Authors:C. Marton, L. Kálmán, T. Árendás, P. Bónis, and D. Szieberth
A new method has been elaborated to estimate the length of the vegetation period of new maize hybrids. According to this method, the length of the vegetation period is expressed by the FAO number, calculated from the following traits:
Grain moisture when the average grain moisture of maturity group standards is 25%
Grain moisture when the average grain moisture of maturity group standards is 20%
Grain moisture at harvest.
The standards of the neighbouring maturity groups are also included in each experiment.The results obtained with this method were compared to the heat unit (GDD) method and to other methods of calculating FAO numbers. The new method has several advantages over previous techniques based on moisture content alone: the fluctuation of the estimated FAO number over locations and years decreased, as did the significant differences between the calculated FAO numbers; the reliability and precision of the new FAO number is less dependent on the date of harvest (moisture content); and the FAO numbers calculated with the new method are in the closest correlation with the heat unit estimates.