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  • 75 years of the chestnut blight fungus Cryphonectria parasitica (Murr.) Barr in Europe
    82-85
    Views:
    171

    The chestnut blight fungus Cryphonectria parasitica is a native pathogen in East Asia and has been introduced into North America and Europe. Historical records and population genetic studies revealed at least three major introduction events from Asia into Europe.

    Nowadays, chestnut blight is present in almost the entire distribution range of European chestnut, i.e. from the Iberian Peninsula to the Caucasus. The C. parasitica population in most countries has been studied in respect to the diversity of vegetative compatibility (vc) types and the occurrence of hypovirulence. The vc type diversity of the different populations varied considerably. Typically, a high diversity of vc types has been found in areas with a long history of chestnut blight and where sexual recombination between divergent genotypes commonly has occurred. On the other hand, newly established populations often showed a low diversity with only one, or a few vc types present.

    Hypovirulence, i.e. the occurrence of C. parasitica isolates infected by Cryphonectria hypovirus 1 has been found widespread in Europe. Natural dissemination and active biological control applications have lead to a high prevalence of the hypovirus and to the recovery of many chestnut stands. Virulent cankers became hypovirus-infected within a short time and ceased expansion. There is concern that the diversity of vegetative compatibility types could increase in Europe through sexual reproduction between C. parasitica genotypes originating from different introductions. A higher level of vegetative incompatibility would not only hamper hypovirus spread within a population but could also select for lower virulence in CHV-1 and subsequently lead to an erosion of biological control. Recent studies, however, indicate that the vc type barriers are not so restrictive than previously assumed and that so far no evidence for an erosion of biological control system in high diversity populations can be observed.

  • Relationship between the change of soil moisture content of different soil layers and maize yield
    19-25
    Views:
    151

    The development of chernozem soil water management and its relationship with maize yields was studied in a 30-years long-term field experiment with different crop-rotation systems (mono-, bi- and triculture), in three crop years with different natural precipitation: a drought (2007), a wet (2008) and a dry (2009 one. The relevant soil layer was divided to three sub-layers: (0–60 cm, 61–120 cm, 121–200 cm) in which the development of soil moisture content was investigated during the whole vegetation. From the results it can be stated that change of the water stock of the upper soil layer (0–60 cm) was the most intensive. Both the direct effect of natural precipitation and irrigation could be observed in the most obvious way in it. Yield result of maize and the highest water supply deficit values in the vegetation were compared in our work too. According to the results it was revealed that among the three studied crop rotation systems it was the monoculture, the success of production of which depends the most of water supply. The most favourable crop rotation system was the triculture from both the aspect of the yield of produced crops and the favourable soil properties too.

  • Nutritional disorders of arable crop growth in eastern Croatia
    273-290
    Views:
    136

    Nutritional imbalances accompanied with growth retardation of crops at early growth stage were found since the last 40 years on certain arable lands in eastern Croatia. In this regard, phosphorus (P) deficiencies in maize and wheat were found mainly on acid soils of the western part of the region, potassium (K) deficiencies in maize, soybean on the hydromorphic neutral to alkaline calcaric drained gleysols of Sava valley lowland, while zinc (Zn) deficiencies were observed mainly in seed-maize and soybean on neutral calcaric eutric cambisols of the eastern part of the region. Cold and moist spring is factor promoting P deficiency symptoms. As oasis of normal crops existed on same arable land, comparison of plant and soil composition was possible from typical sites. P nutrition disorders were in connection with the lower P and the higher aluminum (Al) and iron (Fe) concentrations in the top of plants and the lower soil pH values. K-deficiency as result of strong K fixation and imbalances with high levels of magnesium (Mg) were the main responsible factors of low maize and soybean yields on some drained gleysols. Chlorosis incidences typical for Zn deficiency in maize and soybean were in close connection with the higher soil pH, the lower quantities of mobile Zn, here and there the higher mobile P in soil, the lower concentrations of Zn and the higher levels of Al and Fe in plants. Overcoming the above mentioned disorders and normalization of yields were achieved using ameliorative fertilization either by K or P fertilizers and in case of Zn by foliar spraying of crops with 0.75% ZnSO4 solution. Also, alleviations are possible by selection of more tolerant genotypes of field crops to specific types of nutritional disorders. From this aspect, some practical solutions were recommended for maize with reference to K nutritional problems.

  • The effect of various composts on vegetable green mass on two soil types
    179-183
    Views:
    136

    Composting of sewage sludges makes easier the utilization of sewage sludge in the agriculture and the composts in good quality could increase the nutrient content of soil. Due to the composting process, the sewage sludge composts with high organic matter content can be utilized in the same way as other composts or farmyard manure.
    Composts produced in different ways have different effects on the physical, chemical and biological properties of different soils, although their positive effects have already proved in the literature. In our study the effects of composts from different composting processes were investigated in soil-plant systems. The different physical and chemical properties of the two examined soil types (arenosol and chernozem)strongly influenced the nutrient supply capacity of composts which could be characterized by the growth of ray-grass as a test plant in the pot experiment. In this work we examined the effects of three different composts on the green weight of plants on the fourth and eighth weeks after the treatment and sowing.

  • Comparison of crop production in Hungary and Tanzania: climate and land use effects on production trends of selected crops in a 50-year period (1968-2019)
    141-149
    Views:
    106

    A comparison of selected crop production for Hungary and Tanzania is presented.  The roles of climate, land use and productivities of crops vary significantly in the two countries. Climate impacts the distribution of crops in Tanzania more than in Hungary as Tanzania’s climate is diverse with hot, humid, semi-arid areas, high rainfall lake regions, and temperate highlands. In contrast, the Hungarian climate is temperate and uniform across the country. Land use changes significantly in Tanzania than in Hungary. Tanzania indicates a reduction in forest land and expanding agricultural land associated mainly with the variation in crop productivities and population growth. To maintain sustainable crop production, increasing crop productivity is of paramount focus to meet the requirements of the growing population.

  • Effect of Copper, Zinc and Lead and Their Combinations on the Germination Capacity of Two Cereals
    39-42
    Views:
    431

    The majority of researchers have studied the following group of microelements: B, Zn, Mn, Cu, Na, Co, Mo, I, Sn, Cl, Al, V, F, Cr, Hg, Cs, Li, Cd, As, Th, Rb, Cr, W, Ti, Sn, Se, Ba, Br. Sporadically, the following elements have been mentioned too: Au, Ra, Hg and Pb. In this study, the effects of copper treatments and their combination with zinc and lead microelements on the germination of maize and barley were investigated using different concentrations of these microelements. Six treatments were used: 1. Copper-sulphate (CuSO4) applied alone, 2. Zinc-sulphate (ZnSO4) applied alone, 3. Copper applied with zinc, 4. Lead-nitrate (Pb(NO3)2) applied alone, 5. Copper applied with lead and 6. Untreated control. Maize (Kiskun SC 297) and barley caryopsis were treated with copper and zinc solutions in the following concentrations: 0.03%, 0.003% and 0.0003%. Maize and barley caryopsis were treated with these solutions for 12 and 24 hours. Maize and barley caryopsis were also treated with lead solutions Pb(NO3)2 with different concentrations: 0.0005%, 0.005% and 0.05%. Maize and barley were treated with these solutions for 12 and 24 hours. In the combined treatments (3 and 5), the same concentration was used for each microelement as in treatments 1, 2 and 4. Control treatments were treated with water for both plant species. Our results showed that copper microelements significantly inhibit germination compared to the untreated control. The toxicity of copper is higher if concentration increases. Zinc microelements also inhibit germination, however its effect highly depends on the microelement concentration. Treatments of copper + zinc also inhibit germination. The two microelements applied together cause more phytotoxicity than they do alone. Lead is highly toxic to plants even in low concentrations. The toxic effect on germination dramatically increased when lead was applied with copper.

  • The effects of fertilization on the protein related properties of winter wheat
    67-69
    Views:
    128

    The yield and quality of wheat are mainly determined by the plant production system, thus we studied the effect of mineral fertilization.

    The field trials were set up in 1983 at the Látókép Research Institute of the University of Debrecen. We examined effect of different Nfertilizer doses (60 kg ha-1 N/P/K, 120 kg ha-1 N/P/K) on Lupus, Mv Toldi and GK Csillag's protein properties in 2012. During the tests, three quality parameters were determined: wet gluten content (%), wet gluten spread (mm/h) and gluten index (%). In the experiment the effect of different doses of N-fertilizers significantly influenced by the wet gluten content and gluten index of Lupus.

  • Caliometric characterisation of crop production byproducts
    55-58
    Views:
    141

    By the decreasing tendency of the fossil energy resources more emphasis put on the usage of renewable energy resources. The consideration of environmental protection and the efforts of the European Union make current the widespread usage of renewable energy within biomass energy. One of the determinative trends of biomass energy is the direct combustion of biomass. Characteristically woody stocks are produced for this aim, but there is a considerable potential in several byproducts of growing herbaceous plants or of other processes.

    In our study three byproducts of plant production have been investigated which appeared at the harvest. The Higher Heating Values of wheat, maize and sunflower byproducts have been determined by an IKA C2000 Basic adiabatic calorimeter. According to the statistical analysis of the measured data the HHV of the byproducts are different, and these values are in a negative correlation with the amount of ash in % (R2=0.873) appeared by the combustion.

  • In memory of József Vörös mycologist (1929–1991) on the 25th anniversary of his death
    33-37
    Views:
    140

    Twenty five years ago died professor József Vörös, internationally recognized mycologist, phytopathologist. On the field of microscopic fungi research, especially on taxonomy of plant pathological conidial fungi (Deuteromycetes, Coelomycetes, Hyphomycetes) gained imperishable reputation during his more than 40 years research activity. As author of 17 fungus taxa and publisher of numerous mycological data J. Vörös took place in the history of mycology.

  • Effect and interaction of crop management factors and crop year on the yield of maize (Zea mays L.)
    31-41
    Views:
    186

    The aim of this study was to determine the combination of treatment levels of crop management factors which can optimize and sustain maize yield under varying climatic conditions. The effect of winter wheat forecrop, three tillage systems (Mouldboard-MT, Strip-ST, Ripper-RT), two planting densities (60,000 & 80,000 plants ha-1), three fertilizer levels (N0-control, N80, N160 kg ha-1) with four replications in irrigated and non-irrigated treatments were evaluated over a five year period, 2015–2019. The obtained results revealed that growing season rainfall positively correlated with yield, whereas, temperature negatively correlated with yield. Impact of adverse weather on yield was less severe in biculture, irrigated plots, at lower planting density (60,000), lower fertilizer rate (N80) and in RT and ST, compared to MT. In years with favorable rainfall, yields of MT and RT were significantly (P<0.05) higher than ST. However, in a less favorable year, such as 2015, with 299 mm growing season rainfall and the lowest July rainfall (59% below mean) there was no significant difference (P>0.05) in yield among the three tillage treatments. Higher planting density (80,000), and fertilization rate (N160) in tandem with MT are treatments combination conducive for high yield under favorable climatic conditions, whereas, in years with low rainfall and high temperatures, RT and ST offer alternative to MT for optimum yield with 60,000 plants ha-1 and N80 treatment level. Crop year effect accounted for 20.7% of yield variance, fertilization 35.8%, forecrop 12.8%, plant density 3.4%, tillage 1.2% and irrigation <1%. It is conclusive that with proper selection of the appropriate levels of agrotechnological inputs the adverse effect of weather on yield can be mitigated.

  • Studies on yield stability in autumn wheat species
    61-66
    Views:
    78

    The environmental adaptability of crop production is basically determined by the selection of biological background (plant species and varieties) suitable for the region and the site. The sowing structure adapted to the ecological background increases the yield and decreases the yield fluctuation caused natural effects. Exact long-term trials are essential to develop variety structure of winter wheat production suitable for the given ecological conditions. We have examined the productivity and yield stability of genetically different state registered winter wheat varieties. We have compared the varieties’ yield results in plot trials, at similar agrotechnical conditions, in different cropyears. We have examined the absolute and relative (compared to the mean of varieties) yield of winter wheat varieties. We have valued the yield stability of genotypes with the help of analysis of variance and linear regression equations. We have defined the connection between productivity and yield stability of varieties. We have pointed out the varieties with good productivity and yield stability in given agroecological conditions.
    According to the results of our examinations the developing of variety structure suitable for the agroecological conditions could increase the potential and effective yield level of wheat production.

  • Gene resources for improvement of drought tolerance and yield quality in dry pea breeding
    105-111
    Views:
    86

    The effectiveness of selection for improved drought tolerance and consumption quality in the progeny of crosses between pea cultivars with semi-leafless (afila) and normal leaves and different origins, respectively, were investigated. After single crosses, parent cultivars and F1, F2 and F3 generations were grown under non-irrigated conditions in the same trials. We created a colour scale from 1 to 9 to measure statistically the shade of seed colour. The tolerance of genotypes against high temperature was measured by the number of pods per plant. The 3:1 segregation
    observed in the F2 generation of crosses between semi-leafless and conventional cultivars indicated that the semi-leafless character is determined by a recessive gene. In contrast, the ratios of conventional (Af) and semi-leafless (af) genotypes were 7:1 and 9:1 ratio in the progenies of crosses of Af × af. The genetic progress was effective for improving the seed quality in F3 generation from crosses Af x af where we found that multiple
    dominant alleles controlled the orange colour of cotyledons and its high heritability (h2 A=0,63). Selection is more effective in producing the genotypes with high yield and normal leaves if the crosses were made between the western European cultivars such as semi-leafless Profi and Delta used as maternal cultivars and conventional Auralia cultivars. In this case, there were decreases in the consumption quality, such as seed size and shade of colour. The selection based on the seed weight of single plants for increasing drought tolerance seemed to be more effective in F4
    strains with normal leaves originated from Czechoslovakian maternal cultivar Y228; however, the genetic progress in the improvement of seed size and colour quality was slow. 

  • The possibility of use of the 0,01 M CaCl2 and Baker- Amacher extractants for the determination of plantavailable potassium
    7-15
    Views:
    71

    The Hungarian fertilizing recommendation systems use AL soil test for the evaluation of potassium supply. The 0.01 M CaCl2 is a definitely milder extractant, it extracts the easily soluble and exchangeable potassium amount. Its European introduction was already taken into consideration in 1994. The research project on this topic is started in several european countries, also in Hungary at the Department of Agricultural Chemisty of Agricultural University of Debrecen. Another advantage this multielement method is that the different element-ratios can also be calculated.
    The Baker-Amacher extractant’s principle is that it contains a known amount of K, P, Mg in the CaCl2 solution. During the soil extraction adsorption and desorption process take place, so the adsorption or desorption can be calculated from the original and the final concentrations.
    In this paper we introduce the results of comparing analysis of the samples (n=630) from Soil Information and Monitoring System. Our aim was to measure the use of new extractants beside conventional extractant (AL) for the evaluation of K-supply would be reasonable.
    It can be stated that there is a medium close relationship (r=0.75) between AL-K and 0.01 M CaCl2-K. My calculations confirmed the results of  former examinations, and proved that the two extractants don’t extract and change the same rate of K-fractions. We found that regression  between 0.01 M CaCl2 and AL depend on texture classes, pH classes, amount of lime, and organic matter content of soils.
    Comparing the relations between AL and Baker-Amacher we find relatively loose correlation (r=0.45). We stated that there are K-fixing soils among soils considered to be well supplied with potassium by AL. This might be caused by the high amount of mineral clay and the quality of mineral clay. We stated that the dK averages show that the Hungarian nutrient-supply categories characterize generally well K-supplement of soil.
    It can be stated that it would be necessary to use new extractants to specify evaluation of plant available K. We found that the 0.01 M CaCl2 and Baker-Amacher extractants could complete usefully the AL procedure and could help effective potassium fertilization.

  • Magnesium uptake dynamism of maize (Zea mays L.) on prairie soil
    83-89
    Views:
    70

    Different influence factors on the magnesium (Mg) uptake in case of three maize hybrids with different long vegetation period have been investigated at the Experimental Station of the University of Debrecen, Centre of Agricultural Sciences and Engineering, at Debrecen-Látókép. The soil of the experiment is a calcareous chernozem, based on loess, with high fertility, that is characteristic for soils of the region Hajdúság.
    Upon irrigation is the experiment divided to main plots, by different hybrids into sub-plots, while treatments of five nutrientsupply levels with fixed N:P2O5:K2O rate (beside control)mean sub-subplots. Soil samples were taken from the upper, cultivated soil layer 3 times during the year 2008. Their pH has been measures in a 0.01 M CaCl2-solution and their Mg-content from the same solution and from ammonium-lactate acetic acid (AL) extract. Plant samples were taken seven times in the vegetation period, of which we measured the Mg-content. Beside this, the during the
    vegetation period by maize biomass extracted Mg-amount has been calculated using fresh and dry matter weights. The effects of irrigation, hybrids and nutrient-supply levels on the soil pH and on the AL- and CaCl2-extractable Mg-amount have been studied, as well. After that I tried to find a correlation between soil pH and the Mg-content of soil determined in different extractants, beside this between the by the two solutions extracted Mg-amount. 

  • Opportunities for improving the nutritional value of cereal-based products
    275-278
    Views:
    159

    We set up experiments for improving the nutritional value of cerealbased products. Our aims were to decrease the energy content of bakery products with the mixing of plant originated raw materials and byproducts with high fibre contents, and we have evaluated the effect of sodium-chloride on the physical properties of bakery products. We found that the apple pomace, the byproduct of juice production, is excellent for increasing of fibre content of bakery products and the further aim of investigation is to develop economical ways of hygienic byproduct handling and purification. Our experiments, evaluate the bakery use of triticale, have significant achievements and the breads made from triticale flour and whole-grain are commercially available nowadays. Our investigations included the possibilities of decrease of toxin contamination of cereals and our results can form a part of risk estimation systems after further experiments .

  • Effect of harvest on the different fertilization methods of asparagus (Asparagus officinalis L.)
    33-37
    Views:
    133

    The experiments were performed in the University of Debrecen Centre for Agricultural Research Institute of Nyíregyháza of 1500 m2 asparagus plantation in 2011. We were determind the number of shoots, plant height, fold thickness and yield of asparagus hybrid. I studied to the effects of various cropyear is addition Grolim hybrid asparagus growth and development. Compared to previous years, 2014 was unusually wet and cold weather conditions which causes the plantation has developed outstanding. The soil temperature early and dynamic increase due to, the harvest had started a one month earlier 2014 than the 2013. The experiment asparagus harvested from lower yields as a result of the extremely dry spring in 2015.

  • Economics of site specific crop density in precision sunflower (Helianthus annuus L.) production
    91-96
    Views:
    67

    In this research, the crop density of sunflower was examined, which, thanks to the tools available for precision crop production and knowledge of the market environment of sunflower production, best fits the heterogeneous areas of the given production zones and meets the economic requirements. These components together directly influence the effectiveness of sunflower production. In the year of 2021 and 2022, we carried out a site-specific crop density sunflower experiment in two fields with the same soil type, by sowing significantly different amounts of seeds within the given zones. We have established that the sunflower, although a plant with excellent adaptability, reacts sensitively to the place of production and the effect of the year, in zones with heterogeneous productivity, and shows a reaction to sowing with a variable number of seeds per zone, even when examined based on economic aspects.

  • Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
    45-51
    Views:
    96

    In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harvested. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials. 

  • Estimation of the vine-shoot yield in the Gyöngyös district
    21-26
    Views:
    109

    Every year, a significant amount of vineyard prunings is generated in Hungary. Instead of utilization them, it is burned directly on the field in spite of the limitations of legalization highly pollute the environment in recent decades. The vineyard pruning itself or with other by-products from pomology and forestry can be significant amount of fuel source. However, before the planning to utilization the essential task is to estimate the potential. This study examine that how many vineyard is generated in the micro-region of Gyöngyös in every year on appointed vineyard.

    In order to vine-branch potential calculate more accurate data was necessary so the products had to be determined for all plant. Thus, the biomass resource and the utilization become plannable. As the result of the experiment we can estimate that 1,5 t/ha vineyard pruning are generated. It means more than 9 thousand tons pruning in the micro-region of Gyöngyös. This amount can be convert into fuel source more than 150 thousand GJ heating value.

    The results evince that the vineyard pruning is important fuel source in every year in the micro-region of Gyöngyös. Further usage is suggested for other regions in other size.

  • Effects of the development of production factors on productivity
    13-18
    Views:
    119

    In every economic sector, the enacted and expected quality of the products strongly affects its market entry and subsistence. The aim of management is success, competitiveness and subsistence that require adequate human and material resources and enough production stock. We must also notice that the quality of tools and instruments significantly influences work productivity. This applies to both plant production and animal husbandry.

    The author researched milk production factors with methodical observation, document analysis and interviews. Data were collected with a ten-year interval, thus this assay can highlight the field, volume and sources of investments during this period and that the production stock increased in most farms and decreased in few. The data also shows the influence of investments on work productivity - there are differences between farms of equal size, so there are still ways of development.

  • Precision crop production and artificial intelligence – the future of sustainable agriculture
    47-58
    Views:
    397

    According to Kay et al. (2004, in Shockley et al., 2017), there are seven steps to the decision-making process: 1) Identify the problem or opportunity, 2) Identify the alternative solution, 3) Collect all data and information, 4) Analyse the alternatives and make a decision, 5) Implement the decision, 6) Monitor the results of the decision, 7) Accept responsibility for the decision. The basic question is what kind of tasks we can perform in the decision-making process and what to leave for Artificial Intelligence (AI).

  • Investigation of the Quality of Winter Wheat in a Sulphur Fertilisation Experiment, 2001/2002
    153-156
    Views:
    103

    We have started a small parcell and a factorial S fertilization experiment with winter wheat in the 2001/2002 cropping year to examine its effect on yield and quality. The scene of experiment was the Latokep Experimental Station of the DE ATC (calcareous chernozeem) in case of small parcell examination and the Agricultural Company of Felsőzsolca (brown forest soil) in case od factorial examination.
    The protein and gluten content of the grain was investigated with PerCon Inframatic 9001 NIR Analyser, then we have measured these parameters with PerCon 8620 infra appliance. After the milling we measured the following parameters: glutenindex, farinographic parameters (farinographic index, water absorption capacity, dough development time, stability, softening, extension) and valorigraphic index.
    Based on the results there’s no justified relation between the fertilization and the protein and gluten content. The valorigraphic index of the samples taken from Felsőzsolca factory characteristically increased as a result of the S-fertilization. In the small-parcell experiment the values of the water absorption capacity, the dough development time and the softening parameters from the valorigrphic parameters depended significantly from the mineral treatments. Signifikant quality improvement wasn’t experieced.
    There was sampling in all of critical phenophase (…). The green plant samples were examined on element content with ICP-OES. These measurements are currently in progress.

  • Studies of Expression of Peptaibol Synthetase of Trichoderma reesei
    188-190
    Views:
    117

    Because of the potential importance of peptaibols in the biological control of plant diseases, a transgenic, a T. reesei strain carrying a tex1-promoter: goxA fusion plasmid was constructed for furthur studies. The peptaibol synthetase gene (which is highly similar to T. virens tex1) was identified in the genome sequence of T. reesei. A 900 bp 5’ upstream noncoding fragment, presumed to include the promoter region of tex1, was cloned into the pSJ3 plasmid (which contains the Aspergillus niger goxA gene encoding glucose oxidase). Finally, we transformed T. reesei with the tex1-promoter: goxA fusion containing pSJ3 plasmid.

  • The Effect of Sunburn on Fruit Quality of cv. Idared Apple
    23-31
    Views:
    78

    The aim of this study is to investigate the effect of sunburn injury on fruit quality parameters (colour-coverage, depth of affected tissue, fruit flesh firmness, soluble solids content) of apple.
    The symptoms of sunburn injury appeared in concentric ring shape, differed from each other and surface colour-coverage. This can be due to the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of the blotch on the transversal diameter of the fruit) dark brown (strongly affected), light brown (moderately affected), pale red transition (poorly affected), red surface colour-coverage (not affected).
    Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low air relative humidity that in the initial phase results in a light corky layer, golden or bronze discolouration, and injuries to the epidermal tissue, in the surface exposed to radiation. Thus it detracts from its appearance, but in most cases, it would not cause serious damage to the epidermal tissue. The depth of affected tissue is not considerable, its values are between 1.5-2.0 mm generally. It is commonly known that the tissue structure of apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
    On the basis of flesh firmness research, the authors established that the measure of flesh firmness of the affected part of apple fruit increases with the effect of sunburn. The consequence of this is the suffered plant cells will die, the water content of this tissue decreases and the fruit gets harder. This water-loss caused the increase of soluble solids content.

  • Correlations study between the selenium content of wheat grass (Triticum aestivum L.) and wheat seeds grown on different soil types
    117-121
    Views:
    96

    In the course of the research we determined selenium and dry-matter content of 35 wheat grasses and 35 wheat seeds. The selenium content of the preparation plant samples was measured by spectrofluorimetric determination (ʎexcitation=380 nm, ʎemission=519 nm) of the resulted piaz-selenol complex. It was established that between the selenium content of the wheat grass and wheat seed the correlation coefficient was 0.36 at p=0.05 level which indicates a medium close correlation. Similarly, there was a medium close correlation between selenium content of the wheat grass calculated on dry-matter basis and total selenium content of the wheat, with a correlation coefficient of 0.40 at p=0.02 level.