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  • Investigation of the impacts of the by-product of sewage treatment on some characteristics of maize in the early growth stage
    77-82
    Views:
    38

    The use of sewage sludge on arable land has been widespread for many years. This by-product, treated as waste, can provide valuable nutrients to the soil, but the applied amount of sewage sludge to arable land is limited. The possibility of application of sewage sludge is essentially determined by the composition of the sludge. The goal of the experiment was to demonstrate that the physiological, morphological, and biochemical parameters of maize (Zea mays L. cv. Armagnac) linearly change with increasing concentrations of sewage sludge (25%, 50%, and 75% as m/m%). The experiment was set up in a glasshouse. The following parameters were investigated: plant height, relative chlorophyll content, photosynthetic pigments (chlorophyll-a, chlorophyll-b, carotenoids), and leaf proline and malondialdehyde (MDA) content, and PS II quantum efficiency in the 3-leaf stages of the plants. Sewage sludge applied in lower doses had a beneficial effect on the initial growth of maize. The relative chlorophyll content was significantly higher in all treatments compared to the control. There was no significant difference in the maximum quantum efficiency of PS II reaction centers among the treatments. In this experiment, different concentrations of sewage sludge treatments had different impacts on the MDA and proline content of maize leaves. The proline content was significantly higher in all treatments, while the MDA content did not change significantly compared to the control.

  • Study of drought stress correlation on yield and yield components of maize cultivars (Zea mays L.)
    67-73
    Views:
    160

    This article was investigated to study the correlation and analysis of drought stress regression on maize cultivars' yield and components. The variance analysis results showed a significant difference between drought stress levels in terms of plant height, total dry weight and number of seeds per row, the total weight of cob, grain yield, harvest index, stem diameter, and cob weight with protective leave. Also, there was a significant difference in ear weight without protective leaves, ear diameter, ear length, plant weight, 100-seed weight, and seed per ear on hybrid treatments. There were statistically significant differences between cultivars in plant height, leaf area, ear diameter, ear length, number of seeds per row, number of seeds per ear, the total weight of cob wood, 100-seed weight, harvest index, plant dry weight. The results of the correlation of traits for the mean levels of drought stress showed a positive and significant correlation between plant yield and plant height, seed per row, ear length and weight of 5 pieces of wood and also with a total weight of cob wood, ear weight with bark showed the highest correlation. There is a significant correlation between leaf area and stem diameter, plant weight, total dry weight at the probability level of 0.05. Correlation coefficients between traits in non-stress conditions showed a positive and significant correlation between grain yield and height, ear length and grain in the row, which was a significant increase compared to stress conditions. The correlation of traits under full stress conditions also showed that the correlation coefficient between cob length trait and positive height was positive and significant. From the study of correlation coefficients between maize traits in non-stress conditions, it can be concluded that the most important components of grain yield are cob length and grain per row. While the correlation coefficients under moisture stress conditions show that the grain trait in the row has a positive and significant correlation with yield, under stress conditions in the cob stage did not show any traits with correlation yield.

  • Results of the sensory analysis of precision maize production
    59-62
    Views:
    175

    This research was carried out in 2018, at the Látókép Experimental Station of the University of Debrecen in a moderately warm and dry production area, on deep humus layered medium-hard calcareous chernozem soil. In the scope of the research, the chlorophyll content of maize (Zea mays L.) was examined under field circumstances by means of local sensory measurements and we were looking for correlation between the obtained values and the amount of yield. Our measurements were carried out with Minolta SPAD-502 and GreenSeeker devices at 3 measurement times (4 leaf stage, 10 leaf stage and silking). It was found that phenological phases had an effect on the obtained SPAD and NDVI values and were in a slightly significant correlation with the yield. The most significant correlation was found between the results obtained during silking and the amount of yield. This may be because the least time has passed between the measurement time and harvest. Results obtained during the 10-leaf stage show excessive values in each case, which can be due to a measurement error. It was found that the phenological phase had an effect on the correlation of SPAD and NDVI values and the amount of yield. As the phenological phase progressed, the correlation between the measured results and yield has increased.

  • Effect of the plant density on different maize (Zea mays L.) hybrids yields and leaf area index (LAI) values
    51-56
    Views:
    145

    We have investigated the plant number reactions of three maize hybrids of various genotypes in a small-plot field experiment. The plant numbers were 50, 70 and 90 thousand ha-1, while the row distances were 45 and 76 cm. The experiment was set on the Látókép Experimental Farm of Centre for Agricultural Sciences of the University of Debrecen in four replications on calcareous chernozem soil.

    The assimilation area and the leaf area index have important role in development of the crop yield. The studied three different genotype maize hybrids reached its maximum leaf area index at flowering. The maximum leaf area index increased linearly with increasing plant density. The season-hybrids reached less yield and leaf area index. According to our experimental results, we have concluded that with the decrease of the row spacing, the yield increased in the average of the hybrids. The studied hybrids reached the maximum yield at 70 and 90 plants ha-1 plant density. We determined the optimal plant number that is the most favourable for the certain hybrid under the given conditions.The higher plant density was favourable at 45 cm row spacing than 76 cm. The hybrids reached the maximum grain yield at 45 cm row spacing between 76 712–84 938 plants ha-1, while the optimum plant density at 76 cm row spacing changed between 61 875–65 876 plants ha-1.

    The leaf area index values between the applied plant density for the flowering period (July 1, 24), we defined a significant differences. In the archived yields were significant differences at the 45 cm row spacing between 50 and 70, 90 thousand ha-1 plant density, while the number for the 76 cm row spacing used did not cause a significant differences in the yield. There were significant differences between the examined hybrids of yields.

  • The effect of production area on the development of yield producing factors of maize (Zea mays L.) hybrids of different genotypes
    67-72
    Views:
    125

    Maize yield amount development is determined by the given crop year and the genotype of the applied hybrid, but beside these also by the applied agrotechnical factors, in particular by sowing technology. The development of yield amount and yield producing factors of five maize hybrids of different genotypes has been studied in a small-plot field experiment by the application of different row spacings and plant density variants. The production of the individual plants shows decreasing tendency parallel to the increasing plant density, however, this decrement is compensated by the higher number of plants per unit production area. Individual plant production is determined by the development of yield producing factors, such as the length and the diameter of cobs, just as by the thousand seed weight – that were studied in the present research work as well.

    In the present research work the decreasing row spacing resulted in a yield increment of 0.67 t ha-1 (4.53%) in 2013, while in contrast in 2014 yield was decreased by 1.75 t ha-1 (14.87%). The high amount of precipitation in March was determinant in 2013: it filled up the soil water stock and balanced the negative effect of the inadequate amount and distribution of precipitation during the vegetation period for the yield. Lower extent of yield increment (0.6 t ha-1) was registered in 2014 in case of the row spacing of 76 cm than in the previous year. In case of a row spacing of 45 cm the difference between the two crop years was 3.1 t ha-1. The highest impact on the yield production factors was found in all treatment combinations in case of the applied hybrid among the three studied treatment factors. In the crop year of 2014 the effect of plant density on cob diameter and thousand seed weight could be revealed as well. In case of the cob diameter significant difference was found between the plant densities of 70 000 and 90 000 plants ha-1, just as between the populations with densities of 50 000 and 90 000 plants ha-1. In case of the thousand seed weight significant differences could be found by the application of plant densities of 70 000 and 90 000 plants ha-1. The highest values of the studied yield producing factors were measured in case of the plant densities of 50 000 and 70 000 plants ha-1; increasing the plant density to 90 000 plants ha-1 resulted in rather decreasing values.

  • Evaluation of striptillage and conventional tillage in maize production
    37-40
    Views:
    156

    Tillage changes soil properties and the way how the environment affects those properties. Soil properties and environment determine the rate of water movement in liquid and gaseous form into and out of soil. Based on the experimental database of the Institute of Land Utilisation, Regional Development and Technology of the University of Debrecen, Faculty of Agricultural and Food Sciences and Environmental Management and the KITE PLC, various cultivation systems were examined with maize (Zea mays L.) as indicator plant in Jász-Nagykun-Szolnok county. The sample area can be found in the outskirts of Kenderes on a meadow chernozem soil. On the examined plot, strip-tillage, subsoiling and moldboard ploughing were performed, each on 4.5 ha, respectively. The purpose of the present study is to compare these cultivation systems according to the soil- and maize kernel moisture content and to the yield based on the years of 2012 and 2013.

  • Changes of some soil chemical and microbiological characteristics in a long-term fertilization experiment in Hungary
    253-265
    Views:
    248

    Agricultural management practices – directly or indirectly – influence soil properties.

    Fertilization rates and crop rotation can strongly affect soil pH, soil nutrient supply and soil organic matter content due to the changes of microbial processes. The objective of this study was to compare the effects of different fertilization doses in monoculture and tri-culture of maize (monoculture: only maize grown since 1983, tri-culture: it is a three-year crop rotation system: pea – winter wheat – maize) on selected soil characteristics. The long-term fertilization experiments were set up in 1983 in Eastern Hungary. These experiments are situated west of Debrecen in Hajdúság loess region, on calcareous chernozem (according to WRB: Chernozems).

    The test plant was maize (Zea mays L.). One-one pilot blocks were selected from monoculture and tri-culture of the long-term experiments. The observed soil samples were taken in the 30th year of the experiment, in 2013. The doses of NPK fertilizers increased parallel together, so the effects of N-, P- and K-fertilizers cannot be separated.

    With the increasing fertilizer doses, the soil pH has decreased in both crop production systems and, in parallel, the hydrolytic acidity has significantly increased. A close negative correlation was proved between the pHH2O, pHKCl and hydrolytic acidity. An increased nutrient content in soil was recorded in every NPK treatment and the available phosphorus and nitrate content increased in higher proportion than that of potassium. Of the measured parameters of C-and N-cycles, fertilization has mostly had a positive effect on the microbial activity of soils. Besides the effects of fertilizer doses, correlation were looked for between soil microbiological properties. Evaluating the ratios among the measured parameters (organic carbon and microbial biomass carbon, OC/MBC ratio; carbon-dioxide and microbial biomass carbon; CO2/MBC proportion), the fertilization rate seems to be favoured by the increase of amounts of organic compounds

  • Magnesium uptake dynamism of maize (Zea mays L.) on prairie soil
    83-89
    Views:
    70

    Different influence factors on the magnesium (Mg) uptake in case of three maize hybrids with different long vegetation period have been investigated at the Experimental Station of the University of Debrecen, Centre of Agricultural Sciences and Engineering, at Debrecen-Látókép. The soil of the experiment is a calcareous chernozem, based on loess, with high fertility, that is characteristic for soils of the region Hajdúság.
    Upon irrigation is the experiment divided to main plots, by different hybrids into sub-plots, while treatments of five nutrientsupply levels with fixed N:P2O5:K2O rate (beside control)mean sub-subplots. Soil samples were taken from the upper, cultivated soil layer 3 times during the year 2008. Their pH has been measures in a 0.01 M CaCl2-solution and their Mg-content from the same solution and from ammonium-lactate acetic acid (AL) extract. Plant samples were taken seven times in the vegetation period, of which we measured the Mg-content. Beside this, the during the
    vegetation period by maize biomass extracted Mg-amount has been calculated using fresh and dry matter weights. The effects of irrigation, hybrids and nutrient-supply levels on the soil pH and on the AL- and CaCl2-extractable Mg-amount have been studied, as well. After that I tried to find a correlation between soil pH and the Mg-content of soil determined in different extractants, beside this between the by the two solutions extracted Mg-amount. 

  • Comparison of Variability among Irradiated and Control Inbred Maize Lines via Morphological Descriptions and Some Quantitative Features
    70-73
    Views:
    60

    Knowledge of genetic diversity in breeding material is fundamental for hybrid selection programs and for germplasm preservation as well. Research has been done with nine irradiated (fast neutron) and four non-treated inbred lines. The aims of this study were (1) to investigate the degree of genetic variability detected with morphological description (based on CPVO TP/2/2) in these materials, (2) to compare the genetic changes among irradiated and non-irradiated maize inbred lines (based on some quantitative features). The irradiation did not change any of the characteristics clearly in positive or negative way, which can be related to the fact that the effect of induced mutation on genetic structure cannot be controlled. From the irradiated lines we have managed to select plants with earlier ripening times and better phenotypes. We could distinguish 3 main groups by the morphological features; these results match our expectations based on pedigree data. Markers distinguishable on the phenotypic level (e.g. antocyanin colouration, length of tassels) were significant in all lines.

  • Az NPK-trágyázás hatása a kukorica tápelemfelvételének dinamikájára, öntözött és nem öntözött viszonyok között
    23-27
    Views:
    155

    The effect of NPK-fertilization on the dynamics of nutrient uptake of maize (Zea mays L., cv. Clarica) was examined on chernozem soil under irrigated and non-irrigated conditions in a field experiment.
    The following results were made:
    • the element concentrations in the plant decreased over time,
    • there is no difference between the dynamics of nutrients on irrigated and non-irrigated sites because rainfall was satisfactory for plants in vegetation period,
    • the N doses not only significantly increase the nitrogen content in maize, but also have a noticable effect on Ca and Mg concentrations,
    • because of the acidifying effect of N-fertilizers, increasing the amount of N-fertilizer increased the Mn, Zn, Cu content of the plants,
    • the P doses have a significant effect on the maize P and N content and the Zn concentration of the plant via P-Zn antagonism in the soil,
    • as the high K doses treatments alter the ion ratios in the soil, the Ca, Mg content of the plant decreased.

  • Effect of sowing technology on the yield and harvest grain moisture content of maize (Zea mays L.) hybrids with different genotypes
    17-22
    Views:
    118

    From the aspect of the efficiency of maize production harvest grain moisture content shall be considered beside the amount of harvested grain yield. Hybrids with different genotypes and vegetation period length lose their moisture content different that is affected by row spacing and plant density – among agrotechnical production factors – depending on the given crop year. In the present research work three crop years with different weather conditions were studied (2013, 2014, and 2015). The small-plot field experiment was set up at the Látókép Field Research Centre of the University of Debrecen, Centre for Agricultural Sciences with four replications on a chernozem soil type. The effect of three factors was analysed in the experiment on yield amount and its moisture content. Factors were row spacing (45 and 76 cm), plant density (50, 70 and 90 thousand plants ha-1), while hybrids were of very early (Sarolta: FAO 290), early (DKC 4014: FAO 320, P 9175: FAO 330, P 9494: FAO 390) and medium (SY Afinity: FAO 470) ripening.

    In the crop year of 2013 the highest yield was produced – regarding the average of the hybrids – by the application of a row spacing of 45 cm (4.5%, 673 kg ha-1), however there was no significant difference between the yield of the populations of different row spacings. Significant difference (14.9%, 1751 kg ha-1; 6.3%, 583 kg ha-1) could be found in case of yield between different row spacing applications in 2014 and 2015. The effect of insufficiently distributed low amount of precipitation and lasting heat days in 2015 could be revealed in yield amounts and harvest grain yield moisture content results that were lower than in the previous years. In 2015 grain yield moisture content varied between 10.3 and 13.9% in case of a row spacing of 45 cm, while by 76 cm between 11.0 and 13.9%.

  • Effect of Ferilizer on the Yield of Maize (Zea mays L.)
    40-46
    Views:
    114

    The effect of fertilization on the yield of maize was examined on chernoem soil with lime deposits at the experimental station at Látókép of the Center for Agricultural Sciences, University of Debrecen. The yields of maize were evaluated using quadratic regression function, in three years – between 2000 and 2002 – in non-irrigated and irrigated treatments. After calculating the regression equations, by derivation of the functions, we have determined the amount of fertilizers needed for maximum yield.
    In the non-irrigated treatments, maximum yield and the active substance amount of fertilizer was as it follows: in 2000, yield of 9,133 t/ha with the application of 384 kg/ha mixed active substance, while in 2002 a yield of 6,289 t/ha with the application 236 kg/ha NPK active substance was achieved. In 2001, due to the favourable precipitation, a yield of 9,864 t/ha was achieved with the application of 245 kg/ha fertilizer. In the case of maximum yield, compared to the unfertilized control, the yield increase was 2,5-5 t/ha. The average increase for 1 kg of NPK fertilizer was 13-19 kg.
    We also determined the necessary fertilizer dosage for maximum yield in irrigated treatments. In 2000, 10,003 t/ha with a dosage of 423 kg/ha, in 2001, 11,542 t/ha with a dosage of 277 kg/ha and in 2002, 8,596 t/ha of maximum yield could be achieved with a fertilizer treatment of 277 kg/ha in the examined three years. The yield increase, in irrigated treatments, varied between 3,9-5,9 t/ha so it was greater than in the case of non-irrigated experimetal plots. The yield increase for 1 kg fertilizer varied between 12-21 kg.

  • Establishing biotic stress tolerance of maize (Zea mays L.) by measuring hydroxamic acid contents
    107-112
    Views:
    181

     

    Cyclic hydroxamic acids are the most considerable secondary metabolites in grasses and their main task is to protect these species from pathogens and pests. The cyclic hydroxamic acid content and common smut susceptibility were examined in our experiments. 27 maize hybrids were used for experimental plants in a climate room, where the plants were grown on a nutrient solution. An infiltration method was used for the inoculation of the plants. The total quantity of cyclic hydroxamic acids was determined and the ratio of infected plants and the ratio of inhibition was determined, too. Based on our results, on the basis of all hybrids’ data, the total hydroxamic acid content of the infected plants was higher than in the control. On the level of individual hybrids, only 9 of them had higher cyclic hydroxamic acid content in the case of infection. Increase in cyclic hydroxamic content induced by the fungus in this case is a tool for the fungus to suppress other pathogens and pests. Amongst the hybrids’ cyclic hydroxamic acid contents, significant differences were detected in the control and in the infected treatment, too. The so-called “sweetcorn” hybrids showed high level of cyclic hydroxamic acid content. According to the differences amongst hybrids, homogenous groups were created which groups differed in the case of control and infected treatment, because of the difference in increase of cyclic hydroxamic acid content. The examined hybrids showed different levels of infection and different rate of growth inhibition for the effect of inoculation. According to the infection caused damage hybrids were ranked. Infection caused notable damage for hybrids Prelude, Desszert 73, DKC5276 and DK440.

  • The effect of water supply and crop year on the yield potential of sweet maize (Zea mays L. convar. saccharata Koern.) hybrids with different genotypes
    203-210
    Views:
    155

    The successfulness of crop production is significantly affected by not only the the average yields that provide cost effectiveness, but also the success of striving for yield safety, therefore, varieties and hybrids tolerant to environmental stress factors are worth being included into the sowing structure. Our aim was to further the decision making of producers in prepaering the right sowing structure by the evaluation of sweet maize hybrids’ tolerance to excess rainfall.
    We performed our examinations in an extremely wet year (2010) on chernozem soil on three sweet maize hybrids (GSS 8529, GSS 1477, Overland) in 12 replications. Comparing the yields of 2010 with those that can be expected under optimal rainfall conditions, we showed that the examined hybrids react to the amount of rainfall higher than their needs with yield depression. The excess rainfall tolerance of the examined hybrids is different in the case of each hybrid.

  • Effect of Irrigation on Maize Yield (Zea mays L.)
    30-35
    Views:
    292

    We have been continually examining the fertilizer and irrigation reaction of commonly cultivated maize hybrids for nearly twenty years at the Látókép experimental station of the Center for Agricultural Sciences, Debrecen University.
    Upon evaluating the results, it can be established that year significantly influences the size of yield. Between the years of 1999 and 2002, in the average of applied fertilizers the difference is 3,4 t/ha, but even in irrigated treatments it reaches 3 t/ha. This is more than the effect of irrigation. Of the applied agrotechnical elements, the yield increasing effect of fertilization is the greatest and can even be greater than the effect of year. The yield increasing effect of fertilization can be reliably detected with small and medium doses, but at higher doses a plateau section is reached, where it is not worth applying more nutrients. Cultivation with irrigation can only be done with appropriate nutrient supply, due to the positive correlation of the two factors. The positive correlation also means that if the water supply of the plant declines, less fertilizer is needed for safe production. The two factors (irrigation and fertilization) have to be increased or decreased at the same time.
    According to the experiment, in unirrigated treatments, 90 kg/ha nitrogen and the related phosphorus and potassium are enough, while in irrigated treatments this was 120 kg.

  • Effect and interaction of crop management factors and crop year on the yield of maize (Zea mays L.)
    31-41
    Views:
    186

    The aim of this study was to determine the combination of treatment levels of crop management factors which can optimize and sustain maize yield under varying climatic conditions. The effect of winter wheat forecrop, three tillage systems (Mouldboard-MT, Strip-ST, Ripper-RT), two planting densities (60,000 & 80,000 plants ha-1), three fertilizer levels (N0-control, N80, N160 kg ha-1) with four replications in irrigated and non-irrigated treatments were evaluated over a five year period, 2015–2019. The obtained results revealed that growing season rainfall positively correlated with yield, whereas, temperature negatively correlated with yield. Impact of adverse weather on yield was less severe in biculture, irrigated plots, at lower planting density (60,000), lower fertilizer rate (N80) and in RT and ST, compared to MT. In years with favorable rainfall, yields of MT and RT were significantly (P<0.05) higher than ST. However, in a less favorable year, such as 2015, with 299 mm growing season rainfall and the lowest July rainfall (59% below mean) there was no significant difference (P>0.05) in yield among the three tillage treatments. Higher planting density (80,000), and fertilization rate (N160) in tandem with MT are treatments combination conducive for high yield under favorable climatic conditions, whereas, in years with low rainfall and high temperatures, RT and ST offer alternative to MT for optimum yield with 60,000 plants ha-1 and N80 treatment level. Crop year effect accounted for 20.7% of yield variance, fertilization 35.8%, forecrop 12.8%, plant density 3.4%, tillage 1.2% and irrigation <1%. It is conclusive that with proper selection of the appropriate levels of agrotechnological inputs the adverse effect of weather on yield can be mitigated.

  • Investigation of the Effect of P-Supply on Maize (Zea mays L.) Development
    171-173
    Views:
    76

    Quantification of plant development is important in areas where the actual dates of certain phonological stages should be identified. The influences of different ecological factors are put into algorithms by crop modellers. In this process the effect of plant nutrients are not yet well quantified. This paper gives data on the effect of phosphorus on maize development prior to flowering stage. The main conclusions are as follows: 1. In lack of phosphorus more degree days are needed for flowering then in case of well P-supply. 2. The effect of P is seen not on leaf initialisation (i.e. final eaf number is the same) but rather on the phyllochron interval. 3. P effect on phyllochron interval can be observed at the younger stage (prior to leaf number 10) but not later.

  • The effect of drought and cropping system on the yield and yield components of maize (Zea mays L.)
    51-53
    Views:
    122

    Different Cropping Systems have many advantages and ensure better crop growth and yielding. Its combination with other agronomic measures can ensure optimal crop density for maximum crop growth and photosynthesis efficiency. The aim of this study was to investigate the influence of different cropping systems on monoculture and biculture rotations [maize- wheat]. The study found that crop rotation does not have a significant effect on the grain nutrition quality, Leaf Area Index (LAI) and Normalized Difference Vegetative Index (NDVI) but has a significant effect on the Soil-Plant Analysis Development (SPAD). Yield and yield components were significantly influenced by crop rotation in this study as yield, plant height, cob weight and number of grains per row all recorded lower mean at 5% probability levels.

  • Comparison of Pálfai’s drought index and the Normalised Precipitation Index in the North Great Plain region
    59-64
    Views:
    152

    Agriculture has always been an important role in economy, food supplies, sustainability of society and creation of job opportunities in Hungary. Our country has resource-related strength of agriculture, because we have more than 4.5 million ha for agricultural production. Agricultural production can be influenced by several factors, including climate, hydrology, soil conditions and antropogenic impacts. Climate determines the quality and quantity of the crop yields. The climate conditions in Hungary are variable and it shows spatial and temporal extremes. As a result of this, drought have become more frequent in our country (2003, 2007, 2009, 2012), which is reflected in the decline in yields as well. In the present study, Pálfai's Drought Index (PAI) and the Standardized Precipitation Index (SPI) were compared 2003–2012 in Debrecen. The temperature and precipitation data were calculated from data provided by a local meteorological station to work out PAI, while the SPI-3 index values were downloaded from the database of the European Drought Observatory. This allowed to drought assessment in a local and regional scale. Our study was supplemented with SPI-3, soil moisture anomalies, PAI and yields of wheat (Triticum aestivum L.) and maize (Zea mays L.) to evaluating the impact of drought on agriculture.

  • Effects of the cropyear and the agronomical factors on agronomical elements of different sweet corn (Zea Mays L. convar. saccharata Koern.) genotypes in long-term experiment
    105-110
    Views:
    97

    In the crop season of 2010 (rainy year), we studied the effect of three agrotechnical factors (sowing time, fertilization, plant density) and four different genotypes on the agronomical characteristics of sweet corn on chernozem soil in the Hajdúság. The experiments were carried out at the Látókép Experimental Farm of the University of Debrecen. In the experiment, two sowing dates (27 April, 26 May), six fertilization levels (control, N30+PK, N60+PK, N90+PK, N120+PK, N150+PK) and four genotypes (Jumbo, Enterprise, Prelude, Box-R) were used at two plant densities (45 thousand plants ha-1, 65 thousand plants ha-1). The amount of precipitation in the season of 2010 was 184 mm higher, while the average temperature was 0.8 oC higher in the studied months than the average of 30 years. Weather was more favourable for sweet maize at the first sowing date, if we consider the yields, however, if we evaluate the agronomical data and yield elements (number of cobs, cob length and diameter, the number of kernel rows, the number of kernels per row) it can be stated that the size of the fertile cobs was greater at the second sowing date due to the lower number of cobs. The largest number of fertile cobs was harvested in the case of the hybrid Enterprise (72367.9 ha-1) in the higher plant density treatment (65 thousand ha-1) at the fertilization level of N120+PK when the first sowing date was applied. The largest cobs were harvested from the hybrid Box-R (cob weight with husks: 516.7 g, number of kernels in one row: 45.7) at the lower plant density (45 thousand plants ha-1) in the second sowing date treatment. Cob diameter and the number of kernel rows were the highest for the hybrid Prelude.

  • Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
    121-126
    Views:
    74

    Pesticides play a key role in fighting weeds, pests and parasitic fungi. According to surveys, pests reduce the yield of agricultural crops by 35% worldwide. Pests, fungi and weeds account for 14%, 12% and 9% yield loss, respectively (Gáborjányi et al., 1995). Chemicals have contributed to increasing and maintaining the yields of crop production for decades. Today, agricultural production (in spite of many efforts) is unthinkable without the use of pesticides (herbicides, insecticides and fungicides). On the other hand, these chemicals contribute to the pollution of the atmosphere, surface and underground waters, and agricultural soils, especially if they are applied improperly.
    The sustainable agricultural production pays attention to environment-friendly cultivation-technologies; but at the same time it makes an effort to produce good quality and economical products. The examination of the herbicides’ secondary effects, fits into this chain of idas namely, how the herbicides affect – stimulating or inhibiting – the soil microbiological processes, prevention of soil fertility.
    In the course of the experimental work the effect of herbicides on soil biological properties were examined in different maize (Zea mays) cultures. We wanted wished to know that how the herbicides affect the quantity change of soil microorganisms, the life of different physiological groups of bacteria and the activity of microorganisms. A small pot experiment was set up in 2008 with the application of two herbicides - Acenit A 880 EC and Merlin 480 SC – in the breeding house of the Department. The moisture content and nutrient supply were at optimal level in the experiment.
    On the basis of results the following can be stated: 
    1. It can be stated that the two herbicides and all their doses affected negatively the number of total soil bacteria, the
    inhibiting effects were significant. The quantity of microscopical fungi increased by the effect of Merlin 480 SC and decreased in the treatments of Acenit A 880 EC.
    2. The Acenit A 880 EC had stimulating effect on the nitrate mobilization. The CO2-production was stimulated by the basic doses of herbicides; the other treatments did not influence the CO2-production significantly.
    3. The quantity of microbial biomass-carbon –except for only one treatment- decreased significantly by the effect of herbicides. Besides it, the quantity of microbial biomass-nitrogen increased significantly in the treatments of Acenit A 880 EC.
    4. The biomass of test plant decreased in the treatments of herbicides, their quantities were smaller than in the control. In the pots treated by Merlin 480 SC, parallel with the increase of doses decreased the quantity of plant-biomass.