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Stripe rust reaction and yield response of winter cereals in bio - versus conventional farming
47-50Views:255In 2014, was an extremely early and heavy yellow rust (Puccinia striiformis var. striiformis) epidemic in Hungary. Significant differences were among locations, years and genotypes in the severity of infection. Ratio of the resistant and moderately resistant genotypes was higher under bio environment. The yellow rust epidemic caused significant yield decreasing in the tested winter cereals.
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The effect of crop coverage on the daily dynamism of the soil’s CO2 emission
97-102Views:338Nowadays one of main goals of international ecosystem research the measurement of greenhouse gases (CO2, N2O and CH4) in different places. The fluctuation of these greenhouse gases – quantity and trend in the case of CO2 and CH4 – could be diverse with atmosphere because it depends on several effects of factors like climate, soil type, vegetation. In grassland out of the three greenhouse gases which fill a part in gas emission, in the case of CO2 soil and vegetation are the most important factors (Soussana et al., 2007).
In the aspect of global carbon balance grasslands are very important by their large area extension, total carbon content, organic content store (10% of the global carbon storage) (Lemmens et al., 2006). In this summer measurements were carried out to determine CO2 emission of the soil from different soil surfaces like grass covered and bare soil surface during a whole day. -
Experiment of quality properties of dehydrated fruits
7-15Views:257The lyophilization is the joint application of freezing and drying. It is an up-to-date conserving procedure, the point of which is that the humidity existing in the frozen humid material is transferred from the solid state directly into the gaseous state at a temperature below 0 oC under vacuum. Out of the procedures applied nowadays, this is the most tolerant drying process.
With regard to the high investment and operational costs, freeze drying is applied only for valuable, heat-sensitive materials when the technological aim is to preserve such properties as aroma, taste and colour as well as such components as proteins and vitamins. This procedure is suitable for drying and conserving certain foodstuffs, stimulants, organic chemicals, medicines and similar sensitive and valuable materials.
In our institute, we have been conducting freeze drying experiments with regional fruits and vegetables since the year 2005. During the first phase, we examined the heat- and material transfer as well as the abstraction of humidity, while during the second phase we analysed the rehydration ability and nutrient content of the freeze-dried materials as compared to those dried with the method of convection. Moreover we have conducted penetration measurements with a portable hardness tester.
To sum up the results gained so far, we can state that the quality of the lyophilized materials is better than those dried in the traditional way. It originates partly in the fact that the temperature and pressure applied for the freeze drying are smaller and the drying period is far longer than for the convection drying.
In contrast to convection-dried materials, freeze dried materials set in close to their original water-content, keep their original shape and size after being rehydrated. The reason of it the porous, spongy structure (flexible cell wall) of the lyophilized products which is able to take up moisture quickly. In addition, the lyophilized products can be rehydrated faster than those dried in the traditional way.
Regarding the results of the chemical analyses, the following conclusion can be drawn: the vacuum freeze drying results a small decrease of nutrient content and nutritive value for the lyophilized products.
The results of the hardness tests support the statement that the majority of agricultural materials cannot be considered as an ideal flexible body, because during the experiment the flexibility coefficient changed when going from the surface of the material inwards. In addition, the penetration tests also confirm that the surface of the convection-dried vegetables is at least 1.5-3 times harder than that of the freeze-dried products. The reason of it that it takes place during the drying denaturation processes.
The article summarizes the results of our research work listed above, in accordance with our experiments conducted by using the characteristic fruits (apple, plum) of the Nyírség Region. -
Different soil fertility conditions depending on different land use methods
169-172Views:204In precision nutrient management the most important aspect is adaptation but we should consider the possibility of the long-term improvement of soil fertility within the less fertile landscape zones. This possibility can be evaluated principally by long-term field experiments, which are running on similar soil types. The results of these field experiments can indicate that which soil fertility status should be attained. Some more important soil fertility data, (such as pH, P-, K- and soil organic matter (SOM) content) of a long-term field experiment with increasing farmyard manure(FYM) doses or equivalent NPK fertilizers, set up on an Eutric cambisol, are presented. The yieldincreasing capacity of FYM doses was only 82%, as compared to the equivalent amount of mineral NPK, but long-term FYM treatments resulted in 10% higher SOM content than that of equivalent NPK
fertilizer doses. The studies indicate that SOM content is a function of local climate and clay content of the soil, and neither long-term high FYM doses can increase SOM content steadily above a supposed steady-state value. However we have to make efforts to keep the optimum level. The lowest soil reactions developed both with the highest NPK doses and without any fertilization. AL-P2O5 content of soil was increased more by mineral fertilization than by FYM treatments, but in case of AL-K2O content there was no difference between the fertilization variants. However the highest doses of both fertilization variants increased soil nutrient content to an excessive degree. Wecould get very valuable data from the unfertilized control plots as well, where long-term yield data suppose 48 kg ha-1 year-1 air-borne N-input.