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Performance of agricultural factors on yield of sweet corn (Zea mays L. Saccharata ) - A review
143-156Views:1451Sweet corn producers and industries require more reliable cultivars which could be accomplished by hybrid breeding. However, progressive phenological growth may be affected by different factors. In this paper, we analyze the key factors that determine the growth and yield of sweet corn. Environmental factors such as temperature and photoperiod were strong determinants of dates of flowering and harvest which are often crucial to yield in diverse climates and agricultural systems, besides the country's pedological conditions, especially soil fertility, affected phenological development. The effectiveness of fertilization in improving sweet corn growth performance was significantly influenced by the soil characteristics, the water supply, the genotype, and the agrotechnological factors. Therefore, genetic improvement of hybrids should be incorporated into the climate and soil elements to stabilize sweet corn yields in various agroecosystems. Decisions made in the sowing period are very significant, as up to 30% of the obtained yield may depend on making the proper choice. Deviation from the optimum date (either early or late sowing) may decrease yield. When deciding about the sowing date of maize, one needs to consider climate, soil quality, geographical location, temperature, weed infestation, sowing seed quality, and the ripening time of the hybrid to be produced.
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Heavy Metals in Agricultural Soils
85-89Views:210The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ. -
Comparative analysis of Staphylococcus aureus strains by molecular microbiology methods
34-39Views:676Staphylococcus aureus is a very important pathogen for dairy farms and milk processing plants. Subclinical mastitis is often caused by this species, and it can contaminate bulk tank milk when milking cows are suffering from mastitis. Additionally, thermostable enterotoxins (SE) produced by some types of this bacterium can cause food poisoning.
The aim of our research was to examine the number of S. aureus in bulk tank milk in two dairy farms and the enterotoxin-producing ability, genetic relation (pulsotype) and antibiotic resistance of S. aureus strains from different sources (bulk tank milk, udder quarter milk and environment).
The results show that the mean number of S. aureus of bulk tank milk of two farms significantly differed (P<0.05). Fourteen isolates were selected for further molecular genetic studies (five isolates were from bulk tank milk and nine isolates were from udder quarter milk). S. aureus was not recovered from the environmental samples. Three of the fourteen isolates (21.4%) tested by multiplex PCR were positive for SE genes. Two isolates carried one gene (seb) and one isolate carried two genes (seg and sei). The fourteen strains were classified into three pulsotypes and two subtypes at 86% similarity level. Isolates from bulk tank milk (n=5), were divided into 2 pulsotypes (A, C) and one subtype (C1). The isolates from udder quarter milk (n=9) belonged to three different pulsotypes (A, B, C) and two subtypes (A1, C1). The distribution of pulsotypes in the present study revealed genetic relationship between S. aureus isolated from udder quarter milk and bulk tank milk. This could be explained by the fact that in farms with a high number of infected cows, these cows could represent the main source of contamination. The results of the antibiotic resistance investigations show, that all strains were susceptible to methicillin, cefoxitin, lincomycin, tetracycline, erythromycin and sulfamethoxazole/trimethoprim. Thirteen out of fourteen strains were resistant to penicillin (A and C pulsotypes, A1 and C1 subtypes) and just one isolate was susceptible (B pulsotype) to all antibiotics tested. -
Effect of soil-compost proportion on the abiotic and biotic parameters of soilplant system
99-104Views:390The environmental awareness, coming to the front in the 21st century, motivates us to supply the plant nutrient demand (in point of the plant, the environment and the human health) with natural materials.
Composting is known since the beginning of civilization. We came to know more the processes of composting as a result of last decades’ research, but numerous unexplained questions remained up to this day. The good compost is dark gray or brown, and it should not create an odor. It has aggregate structure, and it’s pH is neutral. Compost is soil-like (Fehér, 2001), nutrient-rich material, which contains valuable nutrients extracted from soil, so if we recycle this, we can decrease the chemical fertilizer and other (example: mineral energy) expenses.
The reason of that we chose the more accurate cognition of compost utilization is to do more effective the site-specific nutrient supply. This increases the average yield and the quality of yield. Besides we can decrease the harmful effects, which endanger the plant, the environment, and the human body.
During the compost utilization experiment we blended the acid sandy soil with compost in 4 different volumetric proportions (5 treatments) than we set the pots randomized. The advantage of this method is that we can provide equal conditions for plants so we can measure the effect of treatments correctly. Our experimental plant was ryegrass (Lolium perenne L.), that grows rapidly, tolerates the glasshouse conditions, and indicates the effect of treatments well. After the harvest of ryegrass we measured the fresh and dry weight of harvested leaves and the total C-, N-, S-content of the dry matter and of the soil, we examined the pH and the salt concentration of soil as well.
Our aim was to study and evaluate the relations between the compost-soil proportion and the nutrient content of soil and plant. In our previous experiments we confirmed (based on variance analyses) that the compost has a beneficial effect on soil and increases the nutrient content of the soil (Szabó, 2009). But it’s important to appoint that the compound of compost is seasonally change: in winter the selective gathered municipal solid waste contains salt that were applied for non-skidding of roads, but salt has a negative effect to the plant. We proved that in our experiment the 25/75% compost/soil proportion was ideal for the plant. This content of compost effected 6 times higher green matter weight compared to the 100% sandy soil. -
In vitro analysis of the effect of ragweed extract against Monilinia laxa
117-120Views:238Nowadays in Hungary nearly 5 million hectares of agricultural area was infected with ragweed (Ambrosia artemisiifolia). According to the public opinion the ragweed is a weed. From agricultural and public health point of view it is exceptionally dangerous plant. As it contains a number of useful active ingredients, based on this the ragweed is consider a medicinal plant. Our goal was to present that the ragweed contains antifungal active substances as well. In the experiments we used the pre-flowering plants with roots and we extracted the biological active components of dried plant. We tested the biological activity of the extracts against Monilinia laxa in vitro. We related based on our examination that ragweed contains biologically active agents, by which it is hampered the reproduction of the Monilinia laxa.
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Varietal dependent response of barley to soil-borne Waitea circinata infection
100-106Views:327The disease syndrome caused by Waitea circinata, a soil-borne pathogen introduced in the past decade into Carpathian basin, visually indistinguishable of those caused by various Rhizoctonia strains in diverse host plant. Dicotyledonaceous species in general proved to be more tolerant to this new pathogen than monotyledonaceous ones. This mesophilic fungus can seriously damage cereals. The barley varieties, similarly to other plants, exhibited highly different individual reaction to soil borne infection, Bivoy being the most while Maresi the less tolerant among the 9 tested varieties. Two groups could be separated on the base of their response to Rhizoctonia; Jubilant, Bivoy, Pasadena formed one group being moderately tolerant and Anabell, Scarlett, Rex and Omega the other group of more susceptibles. Three significant factors influence on the virulence of Rhizoctonia strains comprised 62% of total variation.
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Consumption of fertilizers in districts of Slovakia in the period 2006–2015
389-398Views:313Consumption of fertilizers in districts of Slovakia in the period 2006–2015 Water quality in the surface streams is influenced by several factors. One of important information which can help us to solve problems with quality of water in water body is a distribution of point and non-point pollution sources in a river basin and also amount of pollutants released from them to surface streams. An example of a point source of pollution is the outlet from wastewater treatment plants (industry, urban areas, farms, etc.). On the other hand the most significant non-point source of pollution is considered the application of fertilizers in agriculture.
In this paper we have evaluated consumption of organic and industrial fertilizers in Slovakia in the period 2006–2015. Total (in tonnes) and average (in kg ha-1) consumption of industrial and organic fertilizers was analyzed. In monitored period, the amount of applied organic fertilizers was much higher than the amount of applied industrial fertilizers and in addition a significant part of total fertilizers consumption had nitrogenous fertilizers in a group of industrial fertilizers. In a group of industrial fertilizers during the period 2006–2015 we observed just moderately increasing in their consumption, while in the period 2010–2015 the average amount of applied industrial fertilizers per hectare of agricultural land increased by about 20 kg ha-1. On the other hand, in a group of organic fertilizers we observed a decreasing in consumption of fertilizers.