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  • Climatic water balance in Hamelmalo, Eritrea
    69-76
    Views:
    170

    Agricultural production is an important sector for peoples to live, but it is highly affected by climate change. To have a good production we need to understand the climatic parameters which adversely affect production. Hamelmalo, which is located in the semi-arid area of Eritrea, is vulnerable to climate change and this is realised in the total production loss. Nevertheless, there is no concrete reference about the climate of the region due to lack of data for a long time. Changes in precipitation (P), evapotranspiration (ET) and, implicitly, in the climatic water balance (CWB), are imminent effects of climate change. However, changes in the CWB, as a response to changes in P and ET, have not yet been analysed thoroughly enough in many parts of the world, including Eritrea. This study also explores the changes of the CWB in the Hamelmalo region, based on a wide range of climatic data (P, relative air humidity and evaporation pan necessary for computing potential evapotranspiration (PET) with the pan evaporation method) recorded at Hamelmalo from 2015-2019. This analysis shows that the annual cumulative CWB for Hamelmalo is negative in 67% of the years. The dry season without precipitation leads to negative CWB and the change in CWB only starts from the raining or crop season. Based on this recent study, 2015 had the highest PET and lowest P, and this resulted in the lowest CWB in the investigated period. Opposite to this, 2019 had lower PET and highest P, which led to the highest CWB. However, the monthly values of CWB did not correlate with the annual P or ET. On the base of our study, it can be concluded that PET and P were very variable in the investigated years and P was the most influential elements of CWB.

  • Effects of Site on Winter Wheat Quality 2002/2003
    100-107
    Views:
    103

    The demand of modern societies for high food quality is evident. Thus, it is important for agriculture to produce row materials that are valuable for nutrition and have favourable characteristics for food processing. For this we need a knowledge about the factors which determine the quality of products. One of the main features of plant production is the “immobility”. This way the characteristics of the field influence the quality of the product, like example winter wheat, which is the main cereal in Hungary and Europe.
    The Concordia Co. has charged the Central Laboratory of Debrecen University, Agricultural Centre with laboratory testing of the 2002/2003 winter wheat crop. The samples consist of thirteen winter wheat varieties from six different sites under the same cultivating conditions. Therefore, the important wheat quality factors were analysed solely against site conditions with the use of Győri’s “Z” index, which contains these parameters.
    Soils were tested first. In this experiment excepting the negligible differences between the sites, there were no linear relations found between quality factors, productivity and soil features. The case is the same with the relation between precipitation, temperature and quality parameters. However, it must be noted that additional soil analyses are required to interpret the extreme results obtained from Karcag.
    The calculated Győri’s Z-index shows relative stability concerning certain varieties, although considerable deviation can be found in varieties related to the sites. According to these results, it can bestated that winter wheat quality was not linearly influenced by soil and weather in the 2002/2003 vegetation period. As the same cultivation technology was used in the experiment, the index was determined by genetic features. It must be noted that these findings are relevant only to this experiment.

  • Precision crop production and artificial intelligence – the future of sustainable agriculture
    47-58
    Views:
    401

    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).

  • Examination of different fungicides against Macrophomina phaseolina in laboratory conditions
    65-69
    Views:
    134

    In Hungary, sunflower is the third most important arable crop, which has a lot of pathogenic fungi. One of these fungi is the Macrophomina phaseolina, which is a well-known fungus in all over the world, since this pathogen has more than 700 host plants. In Hungary, several host plants can be found as well. The M. phaseolina produces microsclerotia, which can survive in the soil and residues for almost 10 years. For now, there is no efficient treatment against this pathogen because of this fungus, since it is extremely resistant and cannot be destroyed easily. The only effective treatment against the fungus is genetic defence. In this study, three different fungicides were tested in vitro against the fungus. The Mirage (prochloraz) seemed to be the most effective fungicide as it completely arrested the hyphal growth. In contrast, the Amistar Xtra (azoxystrobin and ciprochonazol) has only a minor effect on the growth of M. phaseolina. Thirdly, the Retengo (pyrachlostrobin) arrested the hyhpal growth of the fungus with 71% at 100 ppm, in other words, the use of this fungicide seems promising. 

  • The R&D and innovation activity of agribusiness enterprises in Hajdú-Bihar County
    67-71
    Views:
    128

    Economic changes have significantly accelarated in the 21th century. In this turbulent market environment enterprises are forced to adapt continously as they must be flexible in order to meet changing market needs. To achieve flexibility companies require innovation. The economic relevance of innovations is significant in every market sector and agriculture is no exception. Re-dynamizing agricultural innovations is a possibility for the outburst of the Hungarian agriculture. Agricultural enterprises have to face competitors as well and they should give priority to efficiency, sustainability and competitiveness in order to preserve their position in BOTH global and domestic markets. This study examines the innovation potential of the agricultural enterprises in the North Great Plain region based on own databases and case studies.

  • Comparative study of different soybean genotypes in irrigation technology
    91-95
    Views:
    280

    In many places in Hungary, early maturity soybean can be successfully grown. The earlier maturity group of soy which ripened in 110–125 days in most crop areas in Hungary. However, to achieve excellent results, the selection of proper varieties is important too. Successful cultivation is largely dependent on the macro and microclimate of the production area, the nutrient supply of the soil and the cultivation technology. Soybean can be produced in places where the amount of precipitation is right, as the lack of water results in lower yields and deteriorated oil and protein concentrations. In the following study, 2 years (2016 and 2017) are compared to the yield, protein and oil content of the soybeans of the early maturation group in irrigated and non-irrigated treatments. Based on our experiment, it can be stated that, during the irrigation of soybean, oil and protein content and yields did not always change.

  • Effect of molybdenum treatment on the element uptake of plants in a long-term experiment
    121-125
    Views:
    113

    Molybdenum as a constituent of several inmportant enzymes is an essential micorelement. It can be found in all kind of food naturally at low level, however, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants. Our study is based on the long-term field experiments of Nagyhörcsök, where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behaviour of elements: uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop.
    In this work we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction.
    However, in most of the plants we studied increasing molybdenum-treatment enhanced cadmium-uptake. We have found the most significant cadmium-accumulation in the case of pea, spinach and red beet.

  • Comparative study of newly-bred black locust clones with regard to photosynthetic rate and water use efficiency: early evaluation
    5-10
    Views:
    218

    Black locust (Robinia pseudoacacia L.) is one of the most important tree species in Hungary, due to its positive economic impacts. Research to increase its yield, improve its stem quality and enhance its drought tolerance has been ongoing since the 1960s. Of the current research works in this field, the clone trial of the Forest Research Institute, University of Sopron, established in 2020 in the Nyírség region, is worth highlighting. In this experiment 4 newly-bred clones and a state-approved black locust cultivar ('Üllői') are being tested. In the summer of 2022, ‘on site’ measurements of assimilation parameters – net assimilation (An), transpiration (Tr) – were carried out using the LI-6800 portable photosynthesis system. From the data obtained, the water use efficiency (WUE) was calculated. The results of the statistical analysis (Kruskal-Wallis H test) have shown significant differences (p < 0.05) between the clones for all three parameters (An, Tr, WUE) tested. The NK2 clone has performed the highest value for all the parameters studied. However, no significant differences were found between clones NK2 and PL040 for Tr or between NK2 and control ('Üllői') for WUE. Studies of this kind contribute to the improvement of black locust growing through the production and selection of cultivars, which are relatively resistant to the negative effects (drought) of climate change.

  • Biostimulant induce growth, chlorophyll content and fresh herbage yield of alfalfa (Medicago sativa L.) and variegated alfalfa (Medicago × varia Martyn) plant
    19-25
    Views:
    45

    The use of biostimulants is associated with promoting plant growth by stimulating cell division and improving nutrient availability and uptake. A study was conducted at the University of Debrecen, Hungary, to examine the effect of biostimulants on alfalfa growth, chlorophyll content and fresh herbage yield. The experiment was arranged in a randomised complete block design with three biostimulant treatments plus control replicated three times. Data collected were subjected to analyses of variance using Genstat, where significantly different means were separated at a probability of 5% using the least significant difference. The findings show no different variation in plant height or chlorophyll content (SPAD) throughout the early stages of growth. Nonetheless, a notable impact was noted in the latter stages (28 days after biostimulant treatment application) on the growth of the alfalfa plant. Biostimulant treatments did not had effect on fresh yield for second through fourth cuts, but the fifth cut showed a significant effect, with T1 treatment recording the highest herbage yield of 19745 kg ha-1 followed by T2 (Tricho Immun plus Ino Green) and T3 (Tricho Immun), with yields of 19528 kg ha-1 and 17273 kg ha-1, respectively, while the T0 (control) recorded the lowest herbage yield of 12060 kg ha-1. However, the average mean yield indicated the application of biostimulants significantly increased fresh yield herbage by 20.5%. Correlation coefficient values suggested plant height at both 14 and 28 DAH (days after harvest) strongly correlated with fresh herbage yield (r = 0.7756 and 0.7455) which reflected in the increase in fresh herbage yield. Therefore, our results suggest that the use of biostimulants in alfalfa cultivation holds promise for improving growth and yield potential through their positive effects on chlorophyll content and the growth of alfalfa plant.

  • The significance of biological bases in maize production
    61-65
    Views:
    165

    The 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.

  • Organic soybean production in Hungary
    45-52
    Views:
    154

    Organic soy production, particularly for feedstuff in organic animal husbandry, is needed in Hungary and the EU regions. Soybean producing crop area in Hungary has increased in the last years, however, the agroecological potential would allow for a larger soybean production area. This study presents the soybean market in Hungary, and the role of soybeans in protein supply in food and feed, summarising the critical elements of organic soybean production from variety selection to marketing. During the field research, the effects of the agronomical environment on yield potential factors were examined. We aimed to determine how different row spacing and tillage systems affect organic soybean yields of different varieties, with particular attention to the dry region, and determine the specific methods and varieties of soybean that favour these areas. We found that the tillage (plough/grubber), the spacing (wide/narrow), and the variety effects were all significant on morphological variables. The most remarkable difference was seen in plant height and the number of pods per plant, while the number of nodes was also highly impacted by tillage treatment and variety. The nutrition variables were significantly different, mainly as an effect of tillage and spacing interaction with significantly different plant responses of varieties.

  • Comparison of Pálfai’s drought index and the Normalised Precipitation Index in the North Great Plain region
    59-64
    Views:
    164

    Agriculture has always been an important role in economy, food supplies, sustainability of society and creation of job opportunities in Hungary. Our country has resource-related strength of agriculture, because we have more than 4.5 million ha for agricultural production. Agricultural production can be influenced by several factors, including climate, hydrology, soil conditions and antropogenic impacts. Climate determines the quality and quantity of the crop yields. The climate conditions in Hungary are variable and it shows spatial and temporal extremes. As a result of this, drought have become more frequent in our country (2003, 2007, 2009, 2012), which is reflected in the decline in yields as well. In the present study, Pálfai's Drought Index (PAI) and the Standardized Precipitation Index (SPI) were compared 2003–2012 in Debrecen. The temperature and precipitation data were calculated from data provided by a local meteorological station to work out PAI, while the SPI-3 index values were downloaded from the database of the European Drought Observatory. This allowed to drought assessment in a local and regional scale. Our study was supplemented with SPI-3, soil moisture anomalies, PAI and yields of wheat (Triticum aestivum L.) and maize (Zea mays L.) to evaluating the impact of drought on agriculture.

  • The analysis of flour blends as affected by the behaviour of two different quality flours of triticale under different fertilizer treatments
    5-8
    Views:
    168

    Triticale is likely used in many countries in human consumption, due to its advantageous agronomical and nutritional properties mostly in blends. The baking quality of blends depends not just on the proportions of the used flours but also on their individual quality what can be influenced by fertilizer treatments.

    22 flour blends were prepared with commercial wheat flour and triticale wholemeal flour in proportions from 0% to 100%. The triticale was treated with different amount of fertilizers (N30P30K30, N60P0K0). Changes of wet gluten contents and extensograph parameters of the blends were determined. The quality of blends significantly depends on the fertilizer treatment of triticale beside the proportions of the flours. When the N60P0K0 treated triticale was used in blends, wet gluten and extensibility values were significantly higher, but in case of resistant to extensions (Rmax) the N30P30K30 treated samples gave higher values. The measured values of wet gluten and extensibility were above the expected values (synergism), while in the case of resistance to extension the expected values were higher than the measured values (antagonism).

  • Timing it right: The Measurement and Prediction of Flowering
    17-22
    Views:
    62

    Although the model described here was developed from research in controlled environments, there is now considerable evidence that in can be applied to a very wide range of natural environments in several species. Multi-locational trials augmented by successional sowing and, if considered necessary, supplementary illumination in the field to increase daylength, can be used to estimate the values of the model coefficients: (1) to characterize germplasm collections and so predict flowering behaviour elsewhere; (2) for interpreting and understanding crop adaptation; and (3) for genetic analysis of photoperiod sensitivity. We do not yet know whether the model has any contribution to make to the understanding of the biochemical mechanisms of photoperiod and temperature responses, but at the very least, it should provide the basis for indicating the most appropriate environmental conditions, genotypes and physiological stage of the plants most suitable for such investigations.

  • On the connection between spatial development and sustainable landscape in the Northern Great Plain region
    145-148
    Views:
    61

    This paper tries to find connection between sustainable landscape and spatial development policy of the Northern Great Plain region on the basis of specific examples explained in scientific literature. Searching for the common roots of spatial development and sustainability the paper explains two interpretations of sustainability from the view point of landscape, than the most significant element of current landscape change – the polarization of landscapes – will be introduced. This trend in landscape change basically determines the direction of spatial development. This paper analyses the Northern Great Plain region from two different approaches. In the first grouping the region is exposed from the view point of spatial development. In the second partitioning the area is divided into subject matters based on the principles of sustainability and polarization of landscape. This research – analyzing development plans and strategies – considers the current situation within the subject matters.

  • Optimized balance between crop productivity, restoration and maintenance of vital soil functions and soil carbon sequestration and storage – the SmartSOIL (FP7) project
    213-215
    Views:
    95

    Soils provide the most indispensable function of supporting the production of food and feed for a growing human population. At the same time they provide a range of regulating and supporting functions related to climate change and removal of greenhouse gases. The majority of the soil functions are closely linked to the flows and stocks of soil organic carbon (SOC); low levels of both flows and stocks may seriously interfere with several of the essential soil functions and thus affect the ecosystem services that soils deliver. Soil degradation is considered a serious problem in Europe and a large part of the degradation is caused by intensive cultivation practices in agriculture. The aim of the SmartSOIL project is to link the results of different scientific fields through a holistic and multidisciplinary approach and as a result develop a decision making tool contributing to sustainable development.

  • Technological development of sustainable maize production and its effect on yield stability
    379-388
    Views:
    165
    In 2015 and 2016, we examined the effect of NPK nutrients, sowing date and plant density on yield on typical meadow soil. The amount of precipitation was 282.0 mm in 2015 (January–September), 706.0 mm in 2016 and the 30-year averageis 445.8 mm.
    Agrotechnical factors:
    – Experiment a)
               5 Dow AgroSciences hybrid with three sowing dates and three plant densities
    – Experiment b)
    In 2015 eight, in 2016 ten hybrids with different genetic characteristics and growing seasons, with control (without fertilization), N80+PK and N160+PKtreatments, five plant densities (50–90 thousand) with 10 thousand plants difference between the different densities.
    In a drought year, we reached the higher yield in the earlier sowing date and with the lower lower plant density of 70 thousand plants ha-1-. The maximum yield, depending on the agrotechnical factors, was 10–12 t ha-1 in 2015, while in 2016 it was 14–16 t ha-1. Yield stability can be increased using hybrid-specific cultivation techniques.
  • Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
    121-126
    Views:
    77

    Pesticides 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.

  • Comparative analysis of sample preparation methods to determine the concentration of arsenic in soil- and plant-samples
    167-170
    Views:
    140

    Arsenic contamination of the fields and groundwater is a global problem. Alföld is the most affected area in Hungary. Irrigation witharsenic contaminated water, and crop production on the contaminated soil can cause a food safety problem, because arsenic is easy taken up by the cell of the plant roots. To prevent this, very important to monitoring the arsenic content of soils and plants. Inductively coupled plasma mass spectrometry (ICP-MS) is a fast, easy method to determined the concentration of minerals in the case of plant and soil samples The analytical methods can give reliable, results if the analytical process, including the sample preparation method, is the best. The objective of this study was to compare 3 type of sample preparation method which was dry ashing, wet digestion in open system, and microwave digestion. As a result of our experiement shows the microwave digestion is the appropriate method to determined the arsenic content of soil samples. In the case of plant samples we can use wet digestion in open system or microwave digestion as a samle preparation method.

  • Examination of the effects of the cropyear and the nutrient supply on the quality of winter wheat with the help of Győri’s Z-index
    121-125
    Views:
    61

    In the case of winter wheat,the knowledge of several quality features is needed to be able to determine precisely the real quality of the given
    wheat. Several systems have been worked out on the qualification of the winter wheat in Hungary and other countries as well. Evaluating the
    quality is being made more difficult because the different quality features take part in the development of the quality in different degrees and
    the values of the several quality features are in different intervals and these data are different dimension values. On the evidence of the
    results, in the case of considering several features,it can be difficult to rank into one concrete quality cathegory. Researchers are trying to
    develop complex quality index numbers in order to be able to define the quality more precisely. One of these complex quality index numbers
    is Gyıri’s, so called, Z-index.
    In three years from 2006 and 2008, we examined the change of the quality features of nine varieties of winter wheat with the help of the
    Z-index under the influence of the effects of the different cropyears and the fertilizer treatment. The results show that the Z-index of the
    examined varieties of winter wheat were influenced by several factors. Examining the data of the three different breeding years together we
    can observe the corrective effect of the different cropyears on the Z-index, and if we examine the three years separately and together, the
    differences of the quality features of the different varieties differentiate very well, and with the help of the Z-index the comparison of the
    types is easier and perspicuous, and the Z-index represents the different nutrient reactions of the different types as well. On the average of
    the three years, the types gave the best results at N120-150+PK nutrient level. Among the nine varieties the best results were given by Mv Suba,
    GK Békés and Mv Mazurka in the case of both low and higher nutrient levels.

  • The role of non-optimum Fe-Zn ratio in the development of latent zinc shortage in cucumber (Cucumis sativus L.)
    7-11
    Views:
    128

    The general micronutrient deficiency of the soils influences the quality of food production which causes human health problems in several countries as well. The non optimal Fe-Zn ratio can cause latent zinc deficiency – which the plants response in the function of their sensitivity –what has no visual symptoms or the plant shows deficiency symptoms in case of appropriate zinc supply. This phenomenon can cause significant decrease in the crop yield.

    The aim of this study was to prove the role of non optimal Fe-Zn ratio in the evalution of latent zinc deficiency.

    The non optimal Fe-Zn ratio caused decrease in the number of the leaves, the number and length of the internodes, the relative chlorophyll contents and in the dry matter production. According to the results the non optimal Fe-Zn ratio caused difficulties in the metabolism, which decreased the examined plant physiological parameters in the most cases. It can be concluded if there are higher iron contents in the tissues than zinc it can result latent zinc deficiency.

  • Dietary fibre prevalence and its role in human nutrition
    9-13
    Views:
    225

    The role of dietary fibre and its impact on health is increasing. It is worth noting that their beneficial effects on the body are becoming more widely known, but their consumption is still below the recommended daily intake from food. Dietary fibre, as a class of compounds, includes a mixture of plant carbohydrate polymers, both oligosaccharides and polysaccharides. Dietary fibre has been linked to a number of diseases, as its consumption can reduce the risk of cardiovascular disease and type 2 diabetes. They influence the composition of the bacteria present in the human gut. Consuming the right quantity and quality of dietary fibre can play a role in the prevention of certain types of cancer. Nowadays, it is common to produce various fibre-enriched foods, called functional foods, because of the beneficial effects they have previously had on the body. In the present work we want to give a general description of dietary fibre and its role in the body.