No 1 (2001): Special Issue - Journal of Agricultural Sciences
Issues of nitrogen are still of particular importance in crop sciences. 15N-tracer are used to identify the N dynamics in soils and the N transfer between soil and plant. This tool is also helpful in clarifying fertilization problems.
This article points out the special requirements for the application of stable 15N-isotops in agri-chemical
Ceramic suction cups were used for the measurement of N-concentration in soil solutions under different soil and climate conditions in both field experiments of Rostock University and Agricultural University of Debrecen (Hungary). Depending on the soil utilisation the change in the N concentration of the soil solution can be proved on both site...s.
The experimental field of Rostock University can be characterised by its high groundwater table. The nitrogen concentration of soil solutions in the different soil layers were determined by the trend downward of water. In the dactylis (Dactilis glomerata) experiment, the quadruple treatments involved the following: with and without N-fertiliser, with and without harvesting, respectively. In the lower soil layers, the least rising N concentrations were established in case of the treatment without N-fertiliser combined with harvesting. The nitrogen leaching calculated from the infiltrated water quantity and the nitrate N concentration increased in the following order: without N-fertiliser, with harvesting < without N-fertiliser, without harvesting < with N-fertiliser, with harvesting << with N-fertiliser, without harvesting.
The field experiment site of Debrecen can be characterised by a low groundwater table. The effect of N-fertilisation on the nitrate-N concentration of soil solution in the soil layers can be stated unanimously. Permanent nitrate-N leaching cannot be established due to the water upward movement under semiarid climate conditions. Intermittently transfer of nitrate-N between the soil layers is probable in cases of remarkable precipitation.
In the last decade, the 0.01 M CaCl2 extraction procedure was tested as a multi-nutrient extractant. In 1995-97, international joint research activities were carried out within the COPERNICUS project. Detailed calibration of conventional and the 0.01 M CaCl2 extraction procedures for pH, Mg and K were published.
Relatively poor correlations were found between amounts of P extracted by conventional and CaCl2 soil test methods and, therefore, P limit values could not be calculated directly. To characterise the soil P supply at different sites, the CaCl2 desorbed P and the adsorbed P in a modified Baker Soil Test were also applied.
Soil test results of Hungarian long-term fertiliser experiments and recommended CaCl2-P limit values, calculated on yield effects and soil characteristics, are discussed.
The physical characteristics of particles (seeds and fertilisers) can strongly influence their movements both in seeding and spreading machines and in the air. It is therefore essential to study these particles when constructing such machines. In this respect the size, shape, coefficient of friction and aerodynamic resistance of particles are o...f great importance.
Due to their irregular shape, determining the size of particles is a troublesome process. A precise description of particles has to include several sizes and can be obtained from their screen size. Many physical properties of particles are relevant during movement in the air, but the aerodynamic resistance coefficient is the most important (Hofstee et al., 1990). Two types of wheat and four types of fertiliser particles were investigated (supported by the National Scientific Foundation OTKA, T-026482). An elutriator was designed and constructed (Csizmazia et al., 2000), in which an airflow is supplied by a centrifugal fan. Air velocity was measured with a thermal sensor. Particle sizes, mass and terminal air velocity were measured. The influence of the aerodynamic resistance coefficient on the particles’ motion is also discussed.
The study was performed on vipers of the Vipera ammodytes ammodytes species and aimed to establish the differences in voluntary feed intake and venom production between a group of wild, recently captured vipers and a group of born and bred captive vipers. In addition, the influence of sex on both parameters was established. The research brought... evidence of important differences concerning voluntary food ingestion and venom production between the two groups of animals. However, sex appeared not to significantly influence these parameters, both in wild, recently captured vipers and in born and bred captive vipers. Wild animals rapidly accommodated to the microclimate conditions in captivity and readily accepted food.
In synthetic fermentation of lysine (amino-acid) a by-product (Biofert) originates which can be characterized by 6% N-content and other ingredients (vitamins, enzymes, micro-elements etc). In small and large plot experiments Biofert was studied in different agroecological (cropyear, soil), biological (genotypes) and agrotechnical (non-irrigated... and irrigated; N-splitting etc) conditions in order to obtain information about agronomic efficiency and environmental effects of its applications.
Our results proved that Biofert has the same agronomic efficiency as traditional N-fertilizers (applied in equal doses and splitting), but Biofert has economic and environmental advantages (less N-leaching in soils) for maize production. We found a special interaction between N-supply and irrigation. In maize production (irrigation) with the optimum application of nutrient- (N-fertilization, Biofert) and water- supply we could stabilize maize yields at a high level (11.0-14.0 t/ha) fairly independently of agroecological factors. When applying Biofert in autumn, NO3-N leaching was less in 100-200 cm chernozem soil-layers than for applications of traditional N-fertilizer. There were no differences between different maize genotypes concerning the agronomic efficiency of Biofert. In maize production 120-190 kg/ha N (chernozem soil) and 165 kg/ha N (meadow soil) doses of Biofert were the optimum doses in splitting applications (autumn + spring).
The crop rotation experiment, established by Vilmos Westsik in 1929, is the best known and most remarkable example of continuous production in Hungary. It is still used to study the effects of organic manure treatment, develop models and predict the likely effects of different cropping systems on soil properties and crop yields. Westsik’s cro...p rotation experiment provides data of immediate value to farmers concerning the applications of fertilisers, green, straw and farmyard manure. The experiment also provides a resource of yield, plant and soil data sets for scientific research into the soil and plant processes which control soil fertility, and into the sustainability of production without environmental deterioration. The maintenance of Westsik’s crop rotation experiment can be used to illustrate the value of long-term field experiments.
The effect of soil temperature was evaluated on the yield of the Occitan corn hybrid at a depth of 5 cm. We examined this effect on the time required from planting to emergence for three average durations: five, ten and fifteen days, all calculated from the day of planting. Winter plowing (27 cm), spring plowing (23 cm), disc-till (12 cm) treat...ments and 120 kg N per hectare fertilizer were applied. As a result of our analysis, we determined the post planting optimum soil temperatures for various time periods. The average soil temperature for a time period of 15 days post planting is the most usable for determining actual yields, followed by ten days, with five days proved to be the least usable (winter plow R2 = 0.86, spring plow R2 = 0.87, disc-till R2 = 0.64).
The genotypes for kappa-casein locus were established using PCR-RFLP. Genome DNA for PCR amplification was isolated from hair roots in cows (30 Schwitz individuals), and from frozen semen in bulls (42 bulls of different breeds).
A higher frequency of the B allele in Schwitz (pA = 0.45 and qB = 0.55 in cows and pA = 0.25 and qB = 0.75 in bull
We analyzed the muscular tissue of 6 sheep. Lipid extraction was performed using the Handson and Olley method. TLC separation was performed using 4 separation systems and the best separation method was determined. Visualization was done using a mixture copper acetate and phosphoric acid, at 150 oC.
This study is part of a larger research work that aims to establish the usefulness of corn cobs, a low cost dietary resource, in the growth of ruminants. Corn cobs are found in large amounts in our country (8.2 mil. tons/year). Increasing the quantity of corn cobs to 50% of the diet in lambs resulted in a decrease by 14.57% in the concentrate i...ntake that is needed to obtain one-kg weight increase. In addition, the diet costs were reduced by 16.33% (Mierliţă, 1999). Increasing the quantity of corn cobs to 20-50% of the diet also resulted in multiplication of bacteria from genus Ruminococcus, that are known to represent about 70-80% of the bacteria population in the rumen. In addition, an increased multiplication rate of large protozoas (i.e. Epidinium, Isotrichia, Diplodinium etc) was observed. This explains the high conversion rate of piruvic acid, a carbohydrate fermentation product, into acetic acid, whereas conversion of piruvic acid into propionic acid decreases. In addition, feed intake and the quantity of digested and absorbed fibers increased by 8.46% and 35.09%, respectively. Thus, a reduction in dietary concentrates needed as nutrient supplies was achieved.
We observed the anatomical and morphological development of each compartment of the ruminant stomach in 3. 6. and 14 week old kids. Weaning from milk to roughage foraging, depending on the kids’ ages, stimulated the development of the rumen and reticulum, and decreased the abomasum portion. A 3 week old kid’s rumen has dense and thin papill...as but, with advancing age and with roughage foraging, the number of the papillas on cm2 decreases and their width increases. The omasum tertiary laminae and especially the quaternary laminae are observable only in the advanced age categories.
Expert systems are softwares that incorporate the experience of an expert and support decision makers by leading them through the thinking processes of an expert in the form of „if…then” rules. To use an expert system we have to work with knowledge expressed in a pre-determined form. To do so, we used a shell that can be purchased, and we... acquired knowledge about the topic from experts through interviews and personal monitoring. Attributes that are non-measurable, such as many of the factors determining work-place organisation and revealing knowledge related to it, can be formed into words by using expert systems. The goal of the study was to present a suggested form of expert system model to help judge the level of work-place organisation.
The balance of the sheep and goat branches can be summarised as follows:
If the increase in stock size, specific yields, genetic improvement and modernisation are not realised, several thousand shepherds will lose their jobs and possibilities to work, and their families will lose their only source of livelihood.
Several hundred hectares o
In order to develop a competitive branch, a subsidisation of 10-20 billion HUF is needed until the accession of Hungary to the EU, depending on the scale and progressivity of development. The subsidisation and realisation of the strategic steps would result in:
– the establishment of a registered livestock with 1.5 million ewes, which would ensure better market position for the branch in the EU (5%),
– the establishment of a competitive and marketable branch with a production value of 15-25 billion HUF, calculated using the present price level (after accession, the branch would be self-operating and profitable, with the 6-8 billion HUF/year normative subsidisation by the EU),
– the establishment of a genetic potential which would ensure our participation in profitable international breeding animal market, which provides extra profit,
– the establishment of a sheep husbandry with better genetic potential and phenotypic performance, producing a quality of international level,
– the maintenance of the workplace of more than 10.000 people (saving 3-5 billion HUF/year of the budget),
– the maintenance of the condition of growing areas of grasslands with their advantages (crop protection and public health) whose financial effect is considerable.