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Impact of weather on the spring crops yield in Croatia with emphasis on climatic change and the 2014 growing season
41-46Views:156Main field crops in Croatia are maize, soybean, sunflower and sugar beet. By these crops are covered (status 2014) close to 50% (385 234 ha) of utilized arable land. Global warming, have often adverse influence on field crop yields. Aim of this study was testing precipitation and temperature regimes on spring crops yield in Croatia in 15-year period (1999–2013) and elaboration of the 2014 growing season with aspect of climatic change.
Four growing seasons (2000, 2003, 2007 and 2012) were less favorable for maize because annual yield was bellow 5 t ha-1 (average 4.38 t ha-1), while in four more favorable years (2005, 2008, 2009 and 2010) annual yield was above 6.8 t ha-1 (average 7.32 t ha-1). Average precipitation and temperature for the April-September period in Osijek were 226 mm and 496 mm, 19.6 oC and 18.6 oC, for less and more favorable years, respectively. Yields of soybeans and sugar beet have mainly similar trend as maize yields in function of weather conditions, while sunflower is more susceptible to extremely moist growing seasons (for example, 2001 and 2005: 650 mm and 697 mm precipitation and very low yields in level 1.7 and 1.6 t ha-1, respectively). On the other side, under drought conditions of 2003, 2007 and 2012, yields of sunflower were above average in range from 2.5 to 2.7 t ha-1), while at same period yields of maize, soybean and sugar beet were drastically reduced.
Average precipitation in the April-September period of 2014 for eight selected sites of Croatia was 756 mm or for 68% higher in comparison with the long-term average 1961–1990 with variation among the sites from 520 mm in Osijek to 910 mm in Varazdin. On the other side, average air-temperature in 2014 was 17.8 oC or for 0.7 oC higher with variations among the sites from 17.2 oC in Daruvar and Varazdin to 18.2 oC in Osijek and 18.3 oC in Gradiste. Under these favorable weather conditions, annual yields of maize (8.1 t ha-1), soybeans (2.8 t ha-1) , sunflower (2.9 t ha-1) and sugar beet 63.6 t ha-1) were considerable higher than usual.
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The effect of climatic change on the rheological properties of winter wheat doughs
96-100Views:77In present paper we have examined the effect of climatic change on the extensigraph characteristics of wheat-flours. The baking quality
of winter wheat is largely determined by cultivar, but it can be influenced by weather conditions during growing period. Flours were from 5
cultivars grown at one location in three cropping years. We have found that the extensigraph properties of dough are affected by the weather
conditions, nevertheless, different cultivars distinctly react to the increase of temperature and decrease of precipitation. In generally, the
higher average day temperature and lower precipitation level is favourable to produce winter wheat flour with better quality -
The effect of rising concentration of atmospheric carbone dioxide on crop production
81-84Views:111In 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.
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Impact of tillage systems on maize emergence
129-136Views:29In Europe, there has been a significant change in the way tillage is approached in recent years. This change is due to a growing awareness among farmers, politicians and society as a whole that soil is not a renewable resource in itself. From an agricultural point of view, the greatest impact on soil condition can be achieved through the use of the applied tillage systems. My research takes this approach as a basis when examining the different tillage systems and their impact on the environment. In this context, conventional and a variety of no-tillage systems are examined in this paper. As a next step, it is examined how the environmental conditions created by the different tillage systems influence the emergence of maize hybrids. The analyses are carried out in a multi-factorial, long-term tillage field experiment. The same batch of the same hybrid seed was sown in several crop years, and the effects of environmental conditions on the emergence process were examined. Environmental effects and emergence-related uptake were measured in the examined plots. Measurements of environmental effects included air temperature, precipitation, soil temperature measured at seeding depth, as well as % cover of stem residue on the surface in the treated plots. The first emergence time measurements of the sown crop in the plots of each treatment were compared and relationships between these factors were investigated.
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Monitoring the oxygen level in the Szarvas-Kákafok Deadarm
170-173Views:58The water quality of the Szarvas-Békésszentandrás Dead Körös is generally meso-eutrophic, and meso-saprobic. However, particularly
under higher temperature conditions, the water body may change toward the eutrophic state, even algal blooms could be observed
previously.
The present measurements were conducted during a two week period, twice a day. Three water samples were taken horizontally, from
the surface, bottom and the middle of the water body. The samples were examined in situ. The oxygen content, the temperature, the pH and
the conductivity were measured by potentiometric methods.
Increasing pH was detected in correlation to the temperature, which indicated a rising photosynthetic activity. Also, the O2
concentration showed high variations, especially, when the fresh water supply from the river was stopped, due to a small flood in the river
Körös.
These results indicate the increasing eutrophication processes in the deadarm, and the high load and instability of the ecosystem. -
How have thermal conditions changed in different phenological stages of apple (Malus domestica) in Northeastern Hungary?
137-142Views:29In temperate climates, most fruit trees need cold weather, low temperatures in winter, and a certain amount of heat during the growing season until harvest. One of the most apparent effects of climate change is the elevated temperature in all seasons of the year. In our study, the changes in thermal conditions have been calculated in Hungary's most significant growing region of apples using the Chill Unit for winters and the Growing Degree Days for summers. The meteorological data were obtained from the gridded dataset of the Hungarian Meteorological Service on a 10 km × 10 km grid, so the whole studied area is well-covered over the last 50 years. The results show that the trees are more exposed to early budding than a few decades ago. Furthermore, the accumulated heat amount in summers has increased drastically, which may increase the heat stress and lead to higher yield losses.
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The significance of biological bases in maize production
61-65Views:159The comparative trial has been set up in the Demonstration Garden of the Institute of Crop Sciences of the University of Debrecen, Centre for Agricultural and Applied Economic Studies, Faculty of Agricultural and Food Sciences and Environmental Management in 2012, with 24 hybrids with different genetic characteristics and growing periods. The soil of the trial is lime-coated chernozem, with a humus layer of 50–70 cm.
The weather of the trial year was quite droughty; the monthly average temperature was 3–4 oC higher than the average of 30 years. High temperature, together with lack of precipitation occurred during the most sensitive phenophases of maize (flowering; fecundation, grain saturation).
The following characteristics have been observed: starting vigour, date of male and female flowering, plant and cob height, dry-down dynamics during maturation and the change of yield composing elements has also been quantified. The yield was recalculated to 14% moisture content grain yield after harvesting.
The beginning of the growing period was advantageous, therefore the analysed hybrids could grow a high (above 300 cm) and strong stem. The yield of the hybrids changed between 10.33 and 11.87 t ha-1, but as a result of the unfavourable climatic extremes, their genetic yield potential prevailed only at a rate of 30–40%. However, moisture content by the time of harvesting was good despite its early date (12th September); it remained under below 14% in most cases. Dry-down was measured on a weekly basis between 14th August and 5th September.
The analysis of the qualitative parameters of the maize hybrids (protein %, oil % and starch %) resulted in significant differences. The most significant difference has been observed in the case of protein content (LSD5%=2.01). Oil content was the most advantageous in the case of hybrids belonging to the mid-late growing group (FAO 400). The X9N655 and 36V74 hybrids had the highest oil content (around 4%), while hybrids P9915 and 37F73 had significantly lower oil content. Starch content was above 70% in the case of every hybrid.
Hybrid selection is highly important in terms of yield and yield security of maize, as well as the application of modern biological fundamentals and hybrid specific technology for the improvement of the level of cultivation technology.
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Examinations of soil waterbalance in different crop-rotation systems of maize
41-49Views:73We examined the change of the time of water balance of soil in 25 years old experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture) in dry (2007) and rainy (2008) cropyear in maizestock. According to our findings the values of waterdeficit of soil of maizestock were much smaller in 2008 than values of last year in not irrigated and irrigated plots of three of crop-rotation systems because of favourable supply of precipitation. We found difference between values of waterdeficit of two irrigation treatments. We measured smaller values in irrigated plots of three of crop-rotation systems before sowing. Waterstock of soil started to decrease with the rising of average temperature and despite of increasing of precipitation quantity in this way we calculated higher values of waterdeficit. Precipitation in August and high average temperature intensified the waterdeficit. Waterdeficit achieved highest values of croptime to front of September. We examined waterbalance of soilprofile in 0-200 cm and we concluded that the waterdeficit of the 80-120 cm soilzone was most intensiv in not irrigated and irrigated treatments because of significant rootmass.
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Change of antioxidant compounds of spices during drying
77-81Views:134Spices 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 different 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.
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The effects of the nanoselenium supplementation to the production parameters and the selenium retention of the red drum (Sciaenops ocellatus)
43-48Views:196The selenium is an essential trace element with antioxidant effect, constituent of many enzymes, natural component of the body of the animals. The addition to the fish feed as micro element supplementation is generally accepted. Numerous animal experiments veryfied, that the antioxidant effect of the nanoselenium is higher than other selenium forms. But no much information is available of the usuage at fish.
In the experiment were investigated the effects of the nanoselenium supplementation of a commercial fish feed were investigated to the production parameters and the body tissue composition. The correlation between the accumulated selenium content of the body and the treatment, and the feed conversation was also statistically analyzed beside the production parameters. Furthermore we were curious, if can be toxic the nanoselenium in higher doses.
The experimental stock was placed into 12 plastic tanks (each 70 l water vol.) in a recirculation system for larval rearing. The salinity and the water temperature was constant during the 8 week long experiment. The feeding was ad libitum, 4 times a day. Beside the control five (1, 1.5, 2.5, 5.5, 10.5 mg Se kg-1) duplicated treatment were set.
According to the results, from the production parameters only at the value of FCR and the survival was found significant difference (p<0.05) between the groups. However strong correlation (r=0.752–0.780, p<0.01) was determined between the treatment and the accumulated selenium levels. To analyzed the free fatty acid contentof the fish, we realized, that the selenium uptake significanly enhanced this level at all treatments. The greatest change was found in case of the type n-3 fatty acids.
Established by the results, the higher intake than 0.5 mg Se kg-1 was not changed significantly the production parameters, nevertheless to increase the selenium content of commercial feeds to 1.5 mg Se kg-1 could be rewarding on the rearing of red drum.
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The impact of environmental factors on the measurement of the normalized difference vegetation index
141-147Views:118The level of nitrogen supply of a plant population can be quickly measured with non-destructive optical measurement devices and the differentiated determination of nitrogen shortage and the replenishment of nitrogen can also be carried out. The level of nitrogen supply is based on the fact that the chlorophyll content of crops is in close correlation with nitrogen content and that the amount of chlorophyll can be easily measured on the basis of the light absorption of chlorophyll molecules. The successfulness of optical measurements can be influenced by the change of weather parameters; therefore, it is important to know the correlations between measurement results and weather parameters when it comes to practical use.
The GreenSeeker Model 505 measurement device determines the relative chlorophyll content in the form of the Normalized Difference
Vegetation Index (NDVI) calculated on the basis of the intensity of the reflected red and infrared rays of light from the crop population. The measurements were performed in alfalfa population with 10 replications at five measurement heights and four measurement times. The weather parameters were measured by a weather station located in the middle of the alfalfa population and the correlations between the meteorological data and the NDVI values were examined. During the statistical evaluation of the results, it was established that the NDVI measurement is primarily influenced by the relative humidity of the air, secondly by air temperature and thirdly by wind speed. Relative humidity was in strong correlation with the NDVI values which were also influenced by the measurement height and time. Regression was not significant in the case of 20 cm measurement height, but the measurements above 40 cm height showed significant correlations. The correlation was shown to be strong at each measurement time, but the influence of humidity was the lowest at 11:00 and 14:00. -
Heat stress of cattle from embryonic phase until culling
11-22Views:246Heat stress becomes a serious problem in the livestock sector as it affects cows' performance negatively. The objective of this paper review is to investigate the effects of heat stress during the different phases of the life cycle of cows; embryos, calves, heifers, and cows. Heat stress during early maternal gestation affects the ability of embryos to develop increasing the risk of abortion and early embryonic death. Heat stress during late maternal gestation affects the performance of calves and heifers later in their life, as it reduces growth performance, conducts physiological changes, impaired immunity, changes the behavior, and reduces the length and intensity of the estrus in heifers with decreasing in milk production in the first lactation. On the level of cows, milk quality and production, meat quality, and the final body weight decrease under hot temperatures. Heat stress decreases the conception rate, alters follicle growth, and estrous symptoms. Hormones secretion and physiological changes because of the heat stress conduct to impair the immunity system, and in oxidative stress and death in some cases. Same as for calves and heifers a change in the behavior of cows was detected in order to decrease their temperature.
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Examination of drought stress of two genotype maize hybrids with different fertilization
53-57Views:110In the growing season of 2019, we analysed stress resulting from climatic factors on maize hybrids of different genotypes, with the aim of gaining a better understanding of the physiological responses of each hybrid, which might support the elaboration of a cost-effective irrigation plan.
Our experiments were carried out at the Látókép Experimental Station of the University of Debrecen on calcareous chernozem soil in a small-plot long-term field trial with strip plot design. In the scope of the experiment, N-fertilizer doses were applied as basic fertilizer and top-dressing in addition to the non-fertilized (control) treatment. The 60 and 120 kg N/ha doses applied as basic fertilizers in the spring were followed by top-dressing in the V6 phenophase with a +30 kg N/ha dose. Measurements were carried out with the involvement of the Renfor early (FAO 320) and Fornad (FAO 420) late maturity hybrids-
The stomata of the plants became more and more closed with the progression of the phenological phases; their stomatal conductance decreased. However, the hybrids responded differently to environmental stress. In the case of the Renfor hybrid, the highest conductance (669 mmol/m2-s) was recorded in the V12 phenophase with the 150 kg N/ha treatment. The stomata were more open due to the high turgor pressure, allowing plants to evaporate properly. The plant was in its worst physiological condition on 2nd July, at the time of the appearance of the last leaf in the case of the 120 kg N dose (224 mmol/m2-s). The value measured in the V12 phenophase has already shown that the stomata were closing due to the self-regulating system of the plant. It would have been necessary to dispense irrigation water following the measurement. This confirms the finding that water stress can be prevented by measuring stomatal conductance.
In the case of the Fornad hybrid, stomatal conductance was the highest on 12th June (630 mmol/m2-s) in the 90 kg N/ha treatment and it was the lowest (183 mmol/m2-s) in VT (emergence of the last leaf) phenophase in the 60 kg N/ha treatment. In this case, the appropriate time for applying irrigation water would have been early July, when the conditions for the plants were still adequate. Subsequently, the stomata began to close due to a reduction of the water resources available to them.
There was a significant correlation between soil moisture and stomatal conductance, as well as between temperature and stomatal conductance.
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Effect of extreme crop year on soil moisture in maize
35-40Views:66We examined the change of the time of water balance of soil in 25 years old experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture) in two extreme cropyear in 2007 and 2009 in maizestock.
According to our findings the values of waterdeficit of soil of maizestock were about 100 mm before the sowing time that grew because of considerable deficit of precipitation and high average temperature in months of summer. Values of waterdeficit achieved at the end of August the maximum and lessed a little bit to end of crop time. Decrease of waterstock stopped because of irrigation treatments in irrigated plots but the difference between two irrigation treatments (Ö1-Ö3) vanishedat the end of summer, waterdeficit were higher with 17 mm in monoculture in irrigated plot than value of not-irrigated plot. Considerabler precipitation in Jun effected on waterbalance of soils of three of crop-rotation systems favourable, rapid waterloss starting to april began to lessenat the end of May and started to increase from early in July. Precipitation in Jun had positiv effect on yield also.