In our research we examined the effect of the hybrid, the nutrient supply, the number of plants and the abiotic factors (temperature, amount of precipitation) on the yield, crop quality and yield stability of maize. We devoted special attention to the natural nutrient utilization ability and fertilizer reaction of maize.
The experiment...took place in Hajdúszoboszló on chernozem soil, on a nearly 8 ha field. The size of one plot was 206 m2, this it was a halfindustrial experiment. We tested six hybrids with different genetic characteristics and growing seasons. I analysed the correlation between the nutrient supply and the yield of maize hybrids with control treatment (treatment without fertilization) and with N 80, P2O5 60, K2O 70 kg ha-1 and N 160, P2O5 120, K2O 140 kg ha-1 fertilizer treatments. Yield increasing effect of the fertilizer also depended on the number of plants per hectare at a great extent. The number of plants of the six tested hybrids was 60, 70, and 80 thousand plants/ha.
In Hajdúszoboszló, in 2015 the amount of rainfall from January to October was 340.3 mm, which was less than the average of 30 years by 105.5 mm. This year was not only draughty but it was also extremely hot, as the average temperature was higher by 1.7 °C than the average of 30 years. In the critical months of the growing season the distribution of precipitation was unfavourable for maize: in June the amount of rainfall was less by 31mm and in July by 42 mm than the average of many years.
Unfavourable effects of the weather of year 2015 were reflected also by our experimental data. The yield of hybrids without fertilization changed between 5.28–7.13 t ha-1 depending on the number of plants.
It can be associated also with the unfavourable crop year that the yield of the six tested hybrids is 6.33 t ha-1 in the average of the stand density of 60, 70 and 80 thousand plants per hectare without fertilization, while it is 7.14 t ha-1 with N80+PK fertilizer treatment. That increase in the yield is only 0.81 t ha-1, but it is significant. Due to the especially draughty weather the yield increasing effect of fertilizers was moderate. In the average of the hybrids and the number of plants, increasing the N80+PK treatment to N160+PK, the yield did not increase but decreased, which is explicable by the water scarcity in the period of flowering, fertilization and grain filling.
The agroecological optimum of fertilization was N 80, P2O5 60 and K2O 70 kg ha-1. Due to the intense water scarcity, increased fertilization caused decrease in the yield. As for the number of plants, 70 000 plants ha-1 proved to be the optimum, and the further increase of the number of plants caused decrease in the yield.
The yield safety of maize has not been satisfactory in Hungary for decades. Yield is influenced by the combination of several factors.
In recent years, the frequency of dry years increased and fertilization decreased. These factors call for a rational determination of the plant density.
I studied the relationship between plant density and
In 2003, the weather was dry. In the vegetation period, the amount of precipitation was 78.5 mm lower and the temperature was 0.97 °C higher than the average of 30 years, the number of hot days was 47-60 (days with a temperature higher than 30 °C). However, we obtained favourable results under experimental conditions in 2003 after wheat as a forecrop using the fertilizer Kemira Power.
The weather in 2004 was favourable. In the vegetation period, the amount of precipitation was 93.2 mm higher than the average of 30 years. Although, the distribution of the precipitation could have been more favourable. The yield of the hybrids ranged between 8.87-10.42 t/ha. Among the studied seven hybrids, the early hybrids gave the highest yield at the highest plant density of 90 thousand plants/ha (PR38Y09, PR38A67, PR37D25, PR37M34). However, FAO 400-500 hybrids gave favourable results also at the low plant density of 45 thousand plants/ha (8-9 t/ha). At this plant density, the aeration of the plant stock was better and the hybrids were prone to bringing several cobs. Yield stagnated with increasing plant density (60 thousand plants/ha), then at 75-90 thousand plants per ha, the yield started to increase again.
In 2004 the yield of hybrids was considerably higher than in the previous year. In contrast to yields of 8.87-10.42 t/ha in 2003, yields in 2004 were around 9-12 t/ha.
The yield of the hybrid XO 902 P is above 12 t/ha already at a plant density of 45 thousand plants/ha. It gives maximum yield at the plant density of 90 thousand plants/ha.
The hybrid PR38P92 showed a good response to changing plant density, but its yield was only 9 t/ha at the low plant density value.
In a favourable year, the yield of the hybrids PR38B85, PR37W05, PR37D25, PR37K85 at a plant density of 45 thousand plants/ha 11 t/ha, while at the higher plant density of 90 thousand plants/ha, it ranges around 13-15 t/ha.
Hybrids PR36K20, PR35Y54, PR34H31 have a good individual yield and they are prone to bringing several cobs in favourable years at a low plant density. Their maximum yield at the plant density of 90 thousand plants/ha is almost 16 t/ha.
In 2007, the weather was similar to that of the extremely dry year of 2003. The amount of precipitation in the vegetation period was 41.9 mm lower than the average of 30 years and its distribution was not favourable either.
In the optimum NPK fertilizer treatment at an optimum plant density, the yield of hybrids ranged between 9.32-10.73 t/ha. The highest yields of 10.22-10.73 t/ha were measured for hybrids PR38A79 (FAO 300) and PR35F73 at a relatively low plant density of 60 thousand plants/ha.
In the average of the hybrids, the optimum NPK dosage was N 131, P2O5 82, K2O 93 kg/ha active ingredient.
...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">In practice of world agriculture a long ago the known problem of decline of harvests of agricultural cultures at their permanent growing, scientific explanation of this phenomenon became possible only with appearance of natural sciences. At first the declines of harvests bound to the toxic action of root excretions cultures on her repeated sowing, with development of humus theory of feed of plants of diminishing of harvests at the permanent sowing began to explain impoverishment of soil on a humus.
Aquaponics is the combination of fish farming (aquaculture) and the soilless cultivation of plants (hydroponics). The aquaponics system is an artificial, recirculating ecosystem, in which bacterial processes convert the waste materials in the water used for fish rearing into plant nutrients, and therefore with the generated heat it is suitable...for culturing economically valuable plants, and thus it mitigates the nutrient laden and quantity of the intensive fish producing systems’ effluent water.
The primary goal of our 12 separate unit’s aquaponics system was to gain experience. We would like to find the right plant species, which are fit for that medium, and their crop can be sold. Besides the plants, our attention focused on the fish. Two fish species were included in the experiments, the common carp and barramundi. It was difficult to create them a perfect living space, besides a constantly changing conditions temperature. Apart the above mentioned we had a problem with the number of individuals per tank, the deformity of the fish body and the too high volume of pH (we registered continuous values above 8.4). We get by carps 4.7 grams of weight gain during 15 weeks, because of the bad conditions.
The main problems at the plants are caused by aphesis and protection against sunburn. Even so we have got the multiples of field yields for each plant species. At salad has grown twice of field yields, tomatoes one and half, kohlrabi than 3.5 times more. The causes of multiple yields are the continuous balanced water and the nutrient uptake of plants. Each plant species fit for cultivating in aquaponics and their crops are delicious, chemical -free, safe and marketable. The plants should be more concentrated. After the experiment, it has been determinated that the carp is suitable for aquaponics, but greater weight gain could be achieved with optimal selection of size of rearing units.
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 fiel...d 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.
In our research we examined the effect of the hybrid, the nutrient supply, the number of plants and the abiotic factors (temperature, amount of precipitation) on the yield, crop quality and yield stability of maize. We devoted special attention to the natural nutrient utilization ability and fertilizer reaction of maize.
The experiment took
In Hajdúszoboszló, in 2016 the amount of rainfall from January to October was 605 mm, which was more than the average of 30 years by 160 mm. The yield of hybrids without fertilization changed between 9.63–11.6 t ha-1 depending on the number of plants.
The six tested hybrids is 10.65 t ha-1 in the average of the stand density of 60, 70 and 80 thousand plants per hectare without fertilization, while it is 12.24 t ha-1 with N80+PK fertilizer treatment. That increase in the yield is 1.6 t ha-1, it is significant.
Da Sonka hybrid is sensitive to weather, it is able to produce 6 t ha-1 additional yield in case of favourable condition. However, it has a low stress tolerance. The most stable yields were observed at Kamaria and Pioneer hybrids. The effect of vintage is also an important factor on the yield. In average, the yield of maize was 6.81 t ha-1 in 2015, which was a drought year and 11.86 t ha-1 in 2016 that was a favourable year.
The authors have been carrying out stand evaluation, crop estimation and yield analysis in winter wheat since 2012. The sampling areas were assigned at the fields of the Training Farm of the Faculty of Agricultural and Food Sciences of Széchenyi István University Mosonmagyaróvár according to the structure of the cropping system. According t...o their observations the value of field emergence is always lower than the laboratory germination. The weak emergence is important because the lower plant density cannot be compensated by the increased tillering in spite of having larger plant growth space. It is proven by the fact that they detected strong productive tillering even at 5 and 10 mm plant spacing while there were single-spiked plants at 40-50 mm plant spacing as well. The analysis revealed that the total ear mass and grain mass of wheat plants bearing two or more ears is almost the double than that of the single-spiked plants. It was a further basic experience that the largest ear of ”multiple-spiked” plants is always heavier than the single ear of one-spiked plants. Plants with intense tillering and more ears demonstrate the importance of proper seedbed preparation and drilling and the significance of sowing good quality seeds. These are the factors that determine field germination and emergence, influence the speed and intensity of initial development and by all these factors the sufficient productive tillering. The authors emphasize the use of exact and objective methods at crop estimation, e.g. the relationship between the ear mass and the yield which is in strong correlation whilst ear length and grain mass are not suitable for a precise estimation. The authors conclude that crop estimation and yield analysis must be inevitable tools of modern crop production and will be particularly important in precision agriculture. These tools also qualify the job done by farmers and helps to identify the areas that require special attention.
The yield and crop safety of maize are influenced by numerous ecological, biological and agrotechnical factors. It is of special importance to study one of the agrotechnical elements, the plant density of maize hybrids, which is influenced by the growing area conditions and the selected hybrid.
We have investigated the effects of three...different plant numbers (50 thousand plants ha-1, 70 thousand plants ha-1 and 90 thousand plants ha-1) on the yield of 12 maize hybrids of different genotypes in Hajdúság, on calcareous chernozem soil, in the Látókép Research Farm of the University of Debrecen, Centre for Agricultural Sciences, in 2013. The experiment was set in four replications, besides commonly applied agrotechnical actions. In the experiment, 1 hybrid of very early (Sarolta), 9 of early (P 9578, DKC 4014, DKC 4025, P 9175, NK Lucius, Reseda, P 37N01, DKC 4490, P 9494) and 2 of medium (Kenéz, SY Afinity) maturation were used.
With the increase of the plant number, the number of individuals per unit area increases. According to our experimental results, we have concluded that with the increase of the plant number, the yield increased in the average of the hybrids. In the average of the hybrids, in the case of 50 thousand plants ha-1, the yield was 13 130 kg ha-1, in the case of 70 thousand plants ha-1, it was 13 824 kg ha-1, while in the case of 90 thousand plants ha-1, the yield became 13 877 kg ha-1.
In addition to plant density increase, it is necessary to determine the optimal plant number that is the most favourable for the certain hybrid under the given conditions. To fulfil this aim, we have determined the optimal plant number corresponding to the maximum yield of the given hybrid, within the given plant number range. The optimal and applied plant numbers differ, since the optimal one could only be applied under ideal conditions. Since the agrotechnical actions cannot always be carried out in appropriate quality and one has to adapt to the weather conditions, thus we have determined a plant number range in the case of each hybrid. The hybrids were classified into categories of producible in narrow and broad plant number range.
In the atmosphere, the amount of carbon dioxide and other greenhouse gases are rising in gradually increasing pace since the Industrial Revolution. The rising concentration of atmospheric carbon dioxide (CO2) contributes to global warming, and the changes affect to both the precipitation and the evaporation quantity. Moreover, the concentration... of carbon dioxide directly affects the productivity and physiology of plants. The effect of temperature changes on plants is still controversial, although studies have been widely conducted. The C4-type plants react better in this respect than the C3-type plants. However, the C3-type plants respond more richer for the increase of atmospheric carbon dioxide and climate change.
sorting because the micro organisms, which help the digestion of high fibre plants, are missing in his stomack, that is why they are mostly called „concentrate selectors” (Hoffmann, 1985, 1988, 1989).
These animals should mostly eat easily digestable plants with high nutrition level (pulses, buds, sprouts and flowers), and they are able
Examining the amount and quality of vegetation available on the habitat of roe deer we can identify the species which can satisfy their feed demand. It is known, that roe deer as other large ruminants, from the plant abundance prefer certain plants and plant parts while there are others which are avoided. The identification of the eaten species and the rate of their occurrence in the feed is the first step to become acquainted with the interaction between animal and the surroundings.
On the examined territories there was significant difference between the disembowelled body masses. The does which come from the hunt Nagyszénás weighed 4-5 kilos more than the does from the Csongrád territory. The main feed components were present in different rate in the samples of the territories, in the Nagyszénás samples grain, dicotyledonous herbacous plants were dominant, and were eaten more. The high level of grain in the feed result in better condition and larger body mass.
After the EU-accession we should have a definite idea about what kind of production structure and land use should Hungary obtain to meet the conditions undertaken in the different governmental decisions. In the course of Hungarian land use, significant changes have taken place in the last eighty years. Further changes are influenced by the fact... that according to various decisions, legislative provisions and ideas in a short time the energy orchards’ domiciliation could start in large. For this, financial support can be required from EU-sources. As for the woody energy plants, subsidies can be required for the domiciliation and as for herbaceous plants grants can be required for growing. As far as the latter is concerned, the subsidy will be around 26-27 thousand Ft/hectares according to the plans. However, the cultivation method does not have to be changed to
switch from plow-land to energy plants. The question is if the produced commodity will be received by power plants and if it ensures appropriate income for the farmer. In my research I wanted to find from the given woody energy plants which are those that are the most profitable.
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, wher...e 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 nutrient supply of plants is becoming more important in plant protection since the appropriate condition of plants can be ensured by optimal and satisfactory nutrient supply to avoid nutritional deficiency diseases. Due to the extreme weather conditions, plants are forced to face several stress factors, which lea...ds to deterioration of the plant health. The increasing occurrence of droughts poses threat to nutrient uptake through the roots since all the nutrients can be accessible to the plants only if they are in dissolved form in the soil – which is not possible in the absence of water. Therefore, the importance of foliar fertilizer is becoming a more and more significant part of the nutrient supply, because with the help of this technology the development of any nutrient deficiency can be prevented.
In this experiment, we focused on the efficiency of two different foliar fertilizers on maize. Foliar fertilizers were applied two times, once in the stage with 8 leaves and tasseling phenophase of the maize. To verify the efficiency of the foliar fertilizers, the chlorophyll content of untreated and treated plant’s leaves was measured after each application. Moreover, the length and diameter of maize cobs, thousand kernel weight, protein, oil and starch content were also measured, and the results were compared to the untreated (control) ones. According to the results, in all aspects significant differences were observed and due to the laboratory analysis of leaves, in the case of magnesium and zinc supply the foliar fertilizers were able to prevent the development of nutrient deficiency.
Spices and herbs have been used by humanity for thousands of years, so they are very important plants.
In this study, the change of dry matter content and antioxidant compounds of eight spices (basil, thyme, rosemary, mint, parsley, lemongrass, chives, coriander) have been examined the raw plants and in plants preserved by three differe...nt drying methods (an oven in 50–60°C; drying at room temperature; lyophilisation between -40 and -50°C, under pressure), because we wanted to see the change of the parameters.
The water content of raw plants was very high, i.e. the dry matter content was very low. By the application of the three drying methods nearly 100% of the water has left the plants, with the exception of the lyophilized basil and rosemary.
Based on the results related to the original material, lyophilized has proved to be the best treatment for the preservation of antioxidant compounds, however air drying also showed high results for some spices.
The environment is contaminated with heavy metals and other toxic compounds. One of the most important toxic element is the arsenic (As).
The objective of our study was to investigate the effect of As on fresh and dry weight of sunflower and maize in the early growth phases.
Seedlings were grown in climate room on nutrient solut...ion which were treated with 3, 10 and 30 mg kg-1 arsenic. The plants were treated separately with As(III) and As(V). After 14 day, changes in fresh and dry weight of maize shoots and roots were recorded. In the case of sunflower these parameters were measured after 21 day.
The applied As(III) and As(V) decreased the fresh and dry mass of the shoots and roots of seedlings, especially at concentration 30 mg kg-1. We can draw the conclusion that the treatments of the maize and sunflower roots with arsenic had negative effects on the biomass accumulation. We found that the sunflower plants are more sensitive to arsenic toxicity than maize plants, and all data demonstrate that the As(III) is more toxic to these plants than the As(V).
In the scope of the article, agricultural biogas plants which operate within the region have been analysed together with their linked livestock plants. The study attempts to describe the current condition and future opportunities of the sites. It also covers the description of energy production/use efficiency. The study contains the list of fac...tors determining the economic operation of biogas plants. In the course of the analysis, types, amount and quality of energy produced of different raw materials have been determined within the decentralised energy production.
The amounts of Fe, and Zn were measured in maize seedlings infected by smut gall tumour (Ustilago maydis Dc. Cda.) and in healthy seedlings five days after infection. The amount of elements was also measured under different stress intensities. Due to the infection, as a biotic stress, the amount and distribution of examined elements have been c...hanged. On the bases of the differences in the Fe distribution between the symptoms less and tumorial leaf parts, we have come to the conclusion that the infection also effects the mobilisation of Fe and Zn inside the plants. The Fe uptake was much higher in the infected plants and the tumour development also had an effect on the uptake and distribution of the examined elements. The experiments of infecting maize seedlings by monosporidial strain of crown gall tumour showed no tumour development. We found that the monosporidial strain also acts as a biotic stress and has an effect of iron and zinc distribution. We observed a slight difference in the iron and zinc contents in the roots of corn seedlings infected by different monosporidial sporidium concentrations, while the iron and zinc contents in the shoots were increased by the intensity of the infection. The roots do not form tumours. There is no difference between the roots of the infected and healthy corn seedlings. Since the Fe and Zn contents of the shoots of infected plants depend on the intensity of the infection, we have come to the conclusion that there must exist a „special” communication system regulating the transportation of the examined elements.
In the experiments with infected maize seedlings, it became necessary to get the iron chlorosis before the disease reaches the lethal phase. Although most of the iron reserves are located in the embryo, to accelerate the chlorosis, the endosperm was removed, and it was observed, that the iron chlorosis appears later in maize seedlings when the endosperm is removed. The relative chlorophyll content of the first and second leaves was measured in iron efficient and iron deficient maize seedlings at different times.
The higher IAA content of tumorial plant tissues is already known. The treatment with IAA decreases the iron concentration in the shoots and in the roots of +Fe precultured plants and increases at -Fe precultured ones. The TIBA retards the shoot-to-root transport of IAA. When the seedlings were treated simultaneously with IAA and TIBA, higher iron concentrations were observed in the shoots and in the roots of corn seedlings.
We found extremely high iron concentrations in the roots of infected seedlings and, in line with this, serious damage to the roots was observed that this can be caused by the high iron content generated free radicals. The results demonstrate that IAA has a role in the shoot to root communication.
Conducted are researches of dynamics of glutathione reduced form maintenance in the leaves of arboreal plants which grow in the zones of different level of contamination by industrial emissions of“Red Lead Factory” LTD and ArselorMittal Kryvyi Rig. For comparison, similar investigations were conducted in the intact Botanic Garden in s....c.t. Sofievka. Findings testify to absence of negative influence of industrial emissions and, thus, the arboretum of botanical garden also can be examined as conditional control. It was stated that it is set a few strategies of active oxygen forms and their metabolites deactivation, appearing in cells under action of environment negative factors. To our opinion, fluctuation of glutathione reduced form maintenance can examine as an index of plants stability, on which investigational species can be distributed on steady and moderato steady.
...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">Plain and the influence of the hybrid, plant density, crop rotation, nutrient supply, weeds and irrigation on water use efficiency were studied.
Molybdenum as a constituent of several inmportant enzymes is an essential micorelement. It can be found in all kind of food naturally at low level, however, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants. Our study is based on the long-term field experiments of Nagyhörcsök, where...different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behaviour of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop.
In this work we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction.
However, in most of the plants we studied increasing molybdenum-treatment enhanced cadmium-uptake. We have found the most significant cadmium-accumulation in the case of pea, spinach and red beet.
The agricultural environment is contaminated with heavy metals and other toxic elements, which means more and more threats. One of the most important toxic element is the arsenic (As).
The objective of the study was to investigate the effect of As-treatments on the element content of the different parts of the green peas (root,stem, leaf, po
According to the results the Ca content of root and pod was increased in the case of the 3 mg kg-1 As-treatment, after that decreasing tendency was observed. In the case of the 270 mg kg-1 As-treatment, the Ca content in the root was increased, because some element is able to concentrate in the lower biomass. The Ca-content of stem and leaves was reduced when the plants were treated with more than 30 mg kg-1 As. The lowest As-treatment (3 mg kg-1) increased the Na content in the root, stem and leaves, however in the case of the higher As-dose, decreasing tendency was observed. In the case of the generative plant parts the 3 mg kg-1 As-treatment also increased the Na content, nevertheless in the case of the higher As-treatments lower Na content was measured, however in the case of the highest As-treatment (270 mg kg-1) the Na content was increased in the generative plant parts, probably the Na was concentrated in the lower biomass. In the case of the 90 and 270 mg kg-1 As-treatment the Mo-content also was increased in the generative plant parts. The 270 mg kg-1 As-treatment caused a similar tendency in the case of the generative plant parts as a result of the lower biomass. In the case of the pod and leaves, the lower As-doses did not cause significant changes.
The Mo content was increased in the root and pea when the plants were treated with 3 mg kg-1 As, but in the case of the higher treatments it was decreased. In the case of the stem it was reverse, the lowest As-tretament (3 mg kg-1) decreased, nevertheless the further As-doses increased the Mo content.
The effect of sowing date on maize development and yield was studied in field experiments. The experiment was set up at the experimental garden of the University of Debrecen Centre of Agricultural Sciences Faculty of Agriculture, Department of Plant Sciences in 2005 and 2006 on calcareous chernozem soil. Six hybrids with different genetic chara...cteristics and vegetation period were tested (Sze 269, DK 440, PR37D25, NK Cisko, Mv Maraton, PR34B97) at three different sowing dates.
2005 was a very wet year. The amount of precipitation in the vegetation period was about 150 mm higher than the average of 30 years. No significant differences were observed in temperature. However, the number of sunny hours was much lower during the summer than as usual. This had an influence on yields.
In 2006, there was no risk of inland water in spite of the large amount of precipitation at the beginning of the year. The amount of water available for plants was satisfactory during the season due to the favorable amount of precipitation. Therefore, plants suffered less from the heat in July. However, hail on 22 July caused significant damage. The number of sunny hours in the summer was high enough. The warm, dry autumn helped the water release of plants.
In 2005, the results of the third sowing date could not be evaluated due to the large number of missing plants. The yield of hybrids ranged between 12-14 t/ha for the first sowing date. For the second sowing date, yields ranged between wider boundaries. The hybrid PR37D25 has a very high yield in the case of the second sowing date, and its seed moisture content was favorably low. The yield of hybrid PR34B97 was the lowest at the later sowing date, the prime reason of this was damage caused by Diabrotica virgifera. The seed moisture content at harvest varied between 16-24% for the first sowing date. In the case of the second sowing date, higher values were measured. Hybrids Sze 269 and NK Cisko had favorable water release characteristics. The maximum value of leaf area index was the best in the case of the first sowing date (5-5.5 m2/m2).
In 2006, yields for the first sowing date ranged between 8-10 t/ha. At the second sowing date, more favorable results were obtained. The reason for this is probably that hail caused a higher damage in hybrids with the early sowing date. Plant stock with later sowing date could recover more successfully. Hybrid PR37D25 had very high yields for the second and third sowing dates. The high-yielding hybrid PR34B97 also had high yield, but this was accompanied by higher seed moisture content. Due to the warm, sunny autumn weather, the hybrids had good water-release dynamics and were harvested with a lower seed moisture content than in the previous year. For the first sowing date, the seed moisture content was around 13-14% except for hybrid PR34B97. For the second and third sowing dates, higher values were observed. Leaf area index was significantly reduced in August for all three hybrids due to the hail in July. For the first two sowing dates, the leaves of hybrid Sze 269 were the first to dry similarly to the previous year.
Year had a strong effect on the results in both years.
The climate changes is becoming more damaging to ornamental plants. Besides ornamental species and varieties of plants on public spaces. It will be necessary to use domestic, well adaptable climate-tolerant plant species.
One field of our growing ornamental plants researches from 2001 in the Centre of Agricultural Sciences of University... of Debrecen, is studying drought patient, mainly Hungarian improved annual varieties, which are able to get acclimatized with the landscape. Moreover, we have in view to work out new, economical seedling production technologies. In the program, the excellent drought- and frost tolerant annuals and perennials belongs to the climate change tolerant plants. From the evaluated of species we want to create and spread the application. of the new types of ornamental horticulture culture.