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Spectral analysis of stress symptoms caused by apple powdery mildew (Podosphaera leucotricha
83-88Views:187An orchard can be examined on the basis of spectral data, using methods with which the reflected radiation can be divided into a large number of (several hundreds) small spectral channel (some nm). Calculated on the basis of such hyperspectral data from different index numbers the water supply of foliage conditions can be well characterized.
The research site is an intensive apple orchard, which located in University of Debrecen, Agricultural Sciences Centre, Farm and Regional Research Institute at Pallag. During my experiments the preliminary evaluation of spectral, non-invasive measurement method are carried out for detecting stress symptoms caused by Podosphaera leucotricha.
Based on the results narrow band greenness indices (NDVI705, mNDVI705, mSR705 and REP) can be used for determination of diseased canopy and for the detection of stress symptoms of Podosphaera leucotricha,. These statements can be utilized in precision plant protection systems, since it can be a basis for such integrated active sensors with LED or laser light source, measuring reflectance at the certain spectral range, which can facilitate real time status assessment of orchards and can control precision fungicide utilization.
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The influence of crop rotation and nutrition regime in winter wheat on the phytomass remains and the deposits of weed seeds remained in the ground
10-13Views:131An important problem refers to soil weeds seed bank with special reference to brown luvic soils and relationship between vegetal remains
(roots + stub) and nutrition regime – crop rotation plant. A great number of seeds can be found in first 20 centimeters of soil (plowing
layer). This fact causes a high weeds density, which has a negative effect on the cultivated plants leading to partial or total crop loss. -
Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
121-126Views:77Pesticides 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. -
Improved soil and tomato quality by some biofertilizer products
93-105Views:262The use of microbial inoculums is a part of sustainable agricultural practices. Among various bioeffectors, the phosphorus-mobilizing bacteria are frequently used.
The objective of this study is to investigate the effect of some industrial biofertilizer inoculums, of containing P-mobilizing bacteria on the quantity and some quality parameters of tomato fruits. Spore-forming industrial Bacillus amyloliquefaciens FZB42 (Rhizovital) as single inoculums and combinations with other Bacillus strains (Biorex) were applied on Solanum lycopersicon Mill. var. Mobil test plant. Soil microbial counts, phosphorus availability, yield and fruit quality, such as total soluble solids (TSS) content and sugars (glucose, fructose) were assessed. The results found that single industrial inoculums of FZB42 product had positive effect on P-availability and fruit quality in the pots. Fruit quality parameters, TSS content, soluble sugars were significantly improved (p<0.05). Such better fruit taste was correlated significantly by the most probable number (MPN) microbial counts. Use of such bioeffector products is supported by the positive interrelation among measured soil characteristics and inside healthy quality parameters of tomato fruits.