The classical method of growth analysis was applied to compare the effects of farmyard manure (FYM) and mineral fertiliser on the dynamics of growth and growth parameters in maize (
L.) over a three-year period (2005–2007) in a long-term continuous maize experiment set up using the principle of active agent equivalence in 1959. The experiment included two nutrient levels: (i) the NPK active agent equivalent of 35 t ha
FYM in the form of FYM, FYM + mineral fertiliser or mineral fertiliser alone; (ii) the NPK active agent equivalent of 70 t ha
FYM in the form of FYM, FYM + mineral fertiliser or mineral fertiliser alone. The aim was to determine the mean and maximum values of the plant growth parameters AGR, ALGR, RGR, NAR and LAR and to compare the effects of FYM and mineral fertiliser on maize growth in various years in a long-term experiment. The effect of the treatments and the year were analysed in terms of the dynamics of total dry matter production, leaf area, absolute growth rate, net assimilation rate and leaf area ratio.Both the fertiliser treatments and the year had a significant influence on the mean and maximum values of the given growth parameters during the vegetative growth stage. The rate and duration of growth (AGR and ALGR) were lowest in the unfertilised control and highest in treatments given high rates of mineral fertiliser or combined FYM and mineral fertiliser. In all the treatments the significantly lowest values of maximum NAR were observed in 2005, when the weather was average, with higher values in the drier years (2006 and 2007). The maximum values of LAR were significantly the highest in the droughty year of 2007. It could be concluded from the results that the effects of FYM and mineral fertiliser and that of the year on maize growth can be reliably evaluated with the classical method of growth analysis in long-term experiments.
In a long-term continuous maize experiment set up in 1959, the functional method of growth analysis was applied to investigate the effect of various levels of farmyard manure and mineral fertilisation on the growth of maize (Zea mays L.) and on the dynamics of the growth parameters over a 3-year period (2005–2007). The experiment involved two nutrient levels (based on the active agent equivalence principle): Level l: the NPK equivalent of 35 t ha−1 farmyard manure (FYM), applied in the form of FYM, FYM + mineral fertiliser or mineral fertiliser; Level 2: the NPK equivalent of 70 t ha−1 farmyard manure (FYM), applied in the form of FYM, FYM + mineral fertiliser or mineral fertiliser. The computerised growth analysis program elaborated by Hunt and Parsons (1974) was used to describe the effect of FYM and mineral fertiliser and to evaluate the results. This program fits functions to calculate the absolute growth rate (AGR), the relative growth rate (RGR), the net assimilation rate (NAR) and the leaf area ratio (LAR).The Hunt-Parsons program fitted a third-degree function to the dynamics of total dry matter production and second- or third-degree functions to that of the leaf area growth. The highest mean values of AGR were obtained in treatments with the higher level of mineral fertiliser alone or mineral fertiliser + FYM when the weather was favourable (2.05–2.31 g plant−1 day−1), and in treatments with the lower quantity of mineral fertiliser alone or mineral fertiliser + FYM in the case of dry weather (1.73–1.74 g plant−1 day−1). In 2005 and 2006 the absolute growth rate gave a good characterisation of the various fertiliser effects, which exhibited high values with significant differences, while in 2007 lower AGR values were obtained and no fertiliser effects were observed. In the dry year (2007) the maximum values of NAR and LAR were higher in all the treatments than in the wetter years (except at the lower rate of mineral fertiliser alone). In the case of NAR, the results obtained with the functional method of growth analysis, based on function fitting, were easier to interpret than those obtained using the classical method.It was concluded from the results that in long-term experiments the use of the functional method of growth analysis gave a more precise evaluation of the effects of fertiliser treatments and the year on the growth of maize in the vegetative growth stage and on the mean and maximum values of growth parameters.
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%).
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:Z. Berzsenyi, G. Micskei, I. Jócsák, P. Bónis, and E. Sugár
Research indicates that there is considerable potential for a successful switch from high chemical use to lower-input, more sustainable farming practices for maize. The overall objective of the MicroMaize project was to field-test the performance of innovative microbiological management strategies. The effect of microbial consortia on maize growth and grain yield was studied in 2008 and 2009 at Martonvásár (Hungary) in a 50-year-old long-term fertilisation experiment. The experiment was set up in a split-plot design with four replications. The main plots were the fertilisation treatments: A: control, without fertilisation (N
), B: N
, C: N
, D: N
, E: N
. Three microbial inoculation treatments were the sub-plots: C0: control, no microbial consortia, C1:
A. lipoferum CRT1
P. fluorescens Pf153
G. intraradices JJ 129
A. lipoferum CRT1
P. fluorescens F113
G. intraradices JJ129
. The results indicated that the microbial consortia had no significant effect on maize growth and yield. In the ecophysiological analyses, the microbial consortia were found to have a significant positive effect on the chlorophyll content and on the protein and nitrogen contents of the grain yield in 2009. The long-term results revealed that the mineral fertilisation treatments and the year had a significant influence on the growth, yield and grain quality parameters of maize. The effect of nutrient supplies and year during the vegetative growth phase of maize could be quantified using the mean values of the absolute growth rate (AGR) for maize shoots and roots and with the nutrient stress index calculated from AGR. Further field investigations on productivity and eco-physiological parameters will be needed to estimate the effect of microbial consortia.
Authors:P. Bónis, T. Árendás, I. Jócsák, C. Mikecz, G. Micskei, and L. Marton
Inbred maize lines were treated with normal and double rates of post-emergence herbicides in a small-plot field experiment in one dry and one wet year. The chlorophyll a + b content of symptom-free ear-leaves was determined using a spectrophotometer after 50% silking in order to determine whether various rates of post-emergence herbicides had any effect on the chlorophyll content at flowering and how this was influenced by the type of year. The chlorophyll a + b content of the inbred lines was greatly dependent on the year, with values twice as high in the wet year as in the dry year. Treatment with tembotrione + isoxadifen-ethyl had no effect on the chlorophyll content in either year. Both rates of mesotrione + terbutylazine reduced the chlorophyll a + b content of one stress-sensitive inbred line in the dry year, but not in the wet year. In the wet year bentazone + dicamba increased the chlorophyll content, but only for one line was this effect significant irrespective of the dose. In the dry year the double dose caused a significant increase in this genotype, but the chlorophyll contents of the other lines did not differ significantly from the control.