Darko Kiš

Performance of different eruca acid type oil seed rape cultivars in a Croatian agro-environment

A constant need for energy is necessary and permanent as far as our modern society is concerned. Today we have a large number of projects and studies of different alternative energy resources. Among them the most interesting are biofuels. Due to climatic conditions Europe has decided in favour of the oil production for biodiesel fuel with oil seed rape as the most appropriate culture due to the way of its cultivation as well as the way of fuel production. The aim of these researches was to investigate the economic and other characteristics of the “ 00” European oil seed rape cultivars in the Croatian agroenvironmental conditions and based on the results to introduce the most perspective ones into production.

Energetska vrijednost poljoprivrednih ostataka pira (Triticum spelta L.) − zaboravljene kulture

Pir, krupnik ili dinkel (Lat. Triticum spelta) jedna je od najstarijih žitarica, a potjece iz Azije. Od broncanog doba do srednjeg vijeka u Europi je bio vrlo važna žitarica. Nakon upotrebe zrna u prehrambene svrhe ostaje biomasa pira kao nusproizvod odnosno otpad. Rastuce cijene fosilnih goriva i sve vece zabrinutosti oko klimatskih promjena stvaraju sve vecu potražnju za novim izvorima sirovine za održivu proizvodnju topline. U posljednjih nekoliko godina istraživanja su pokazala pozitivne ucinke uporabe poljoprivrednih ostataka za proizvodnju energije. Zrno pira prerađuje se u razlicite svrhe, dok pljeve, pljevice te stabljika zaostaju kao nusproizvod odnosno ostatak u proizvodnji. Stoga je znacajno provesti istraživanje kako bi se utvrdila energetska (goriva) svojstva pljeve i pljevice te stabljike pira. U radu su obuhvacene dvije sorte pira BcVigor i Ostro. Nakon prikupljenih i homogeniziranih uzoraka za svaku sortu određene su gornje i donje ogrjevne vrijednosti (Hg i Hd). Rezultati dobiveni u ovom istraživanju pokazali su da su pljeve i pljevice te stabljika pira, kao ostatak nakon upotrebe zrna u prehrambene svrhe, vrlo kvalitetna sirovina za proizvodnju energije zbog svoje visoke ogrjevne vrijednosti: gornja ogrijevna vrijednost stabljike sorte BcVigor iznosi 17.367 MJ/kg, a stabljike sorte Ostro 17.224 MJ/kg dok gornja ogrijevna vrijednost pljeve i pljevice sorte Ostro iznosi16.402 MJ/kg, a sorte BcVigor 16.650 MJ/kg.

Anaerobic digestion of specific biodegradable waste and final disposal

The present paper investigates the effectiveness of different levels of applied digested residue obtained after anaerobic digestion (AD) of meat-bone meal (MBM) on the morphologic and mineral characteristics of corn. The experiment was conducted in duration of two years and consisted of eight treatments: control (without any fertilizer) ; mineral fertilization only ; treatments with minimum, medium and maximum dosage of digested MBM ; combined fertilization of minimum, medium and maximum dosages of AD residue combined with mineral fertilizer. Combination of treatments with mineral fertilizer and different rate s of AD residue, plants had increased mass yield, they were larger and had more leaves. Contents of mineral substances were within average values, both in plant material and in kernel, and variations in values were conditioned by total mass and ion interactions. MBM after AD treatment is possible to apply as organic fertilizer. It has higher nutritive value and, as such, is suitable for treatment of agricultural plants, especially in crop production.

High-risk bio-waste processing by alkaline hydrolysis and isolation of amino acids

Slaughterhouse waste can be very dangerous and potential risk for animal and human health. Brains and spinal cords are deemed high-risk substances and can be infected with prions ; their treatment is therefore only possible in strictly controlled conditions. One of the methods which can achieve the necessary reduction in health risk is alkaline hydrolysis. Standard alkaline hydrolysis is at 150°C, 3-6 hours, and 4 bars. In this investigations focus was on different alkaline conditions: temperature (135oC, 150oC, 153oC), time (2, 3, 6 hours), and base (NaOH and KOH) due to fact that amino acids are sensitive to variations on temperature, pressure and base media. Analyzed amino acid composition of hydrolyzed material at different testing conditions show successful hydrolysis. Highest value of protein, which is generally relatively low, was achieved with NaOH at a temperature of 135oC and time of 2 hours, whereas in the reaction with KOH the highest obtained value was achieved at 150oC and 3 hours. A dry substance increasing with time, and the highest value was achieved at the temperature of 150oC and time 6 hours for both bases (NaOH, and KOH). Most of the amino acids went full racemization during the process ; especially in D-amino acids like aspartic acid, glutamic acid, tryptophan and isoleucine. Lysine shows higher resistance to alkaline medium than other amino acids. Isolation of certain amino acids, like: asparagine, glutamic acid, glycine, alanine, and leucine, is possible because they show higher concentrations in hydrolysates.

Effect of precision drill forward speed on in-Row seed spacing accuracy of red beet

The most significant factor for controlling root size of red beet is likely to be the spacing between plants, or the density of seed plantings. Most red beet that is used in processing and for the market, is produced by direct sowing with precision drills at an inter-row spacing of 30 to 60 cm and in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants m-2. The desired plant density per unit area can be achieved by using mechanical and pneumatic precision drills, and by sowing calibrated seeds. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. This was prevalent in cases of drills that used mechanical feed mechanisms, rather than drills with pneumatic feed mechanisms. The best in-row seed spacing distribution accuracy was determined at the speed of 0.83 ms-1 with the pneumatic feed precision drill operated suction system, when 83.1% of seeds were laid at the 0.5-1.5 of the theoretical seed spacing (Zt). Inferior results were obtained with the belt feed mechanism at an operating speed of 1.81 ms-1 (63.4% of Zt).Preliminary communication The most significant factor for controlling root size of red beet is likely to be the density of seed plantings. Most red beet is produced by direct sowing with precision drills at an in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants per m. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. The best in-row seed spacing distribution accuracy was determined at the speed of 0,83 m/s with the pneumatic feed precision drill operated suction system, when 83,1 % of seeds were laid at the 0,5÷1,5 of the theoretical seed spacing. Inferior results were obtained with the belt feed mechanism at an operating speed of 1,81 m/s.

Effect of drill speed and feed mechanisms on in-row seed spacing accuracy of red beet

The most significant factor for controlling root size of red beet is likely to be the spacing between plants, or the density of seed plantings. Most red beet that is used in processing and for the market, is produced by direct sowing with precision drills at an inter-row spacing of 30 to 60 cm and in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants m-2. The desired plant density per unit area can be achieved by using mechanical and pneumatic precision drills, and by sowing calibrated seeds. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. This was prevalent in cases of drills that used mechanical feed mechanisms, rather than drills with pneumatic feed mechanisms. The best in-row seed spacing distribution accuracy was determined at the speed of 0.83 ms-1 with the pneumatic feed precision drill operated suction system, when 83.1% of seeds were laid at the 0.5-1.5 of the theoretical seed spacing (Zt). Inferior results were obtained with the belt feed mechanism at an operating speed of 1.81 ms-1 (63.4% of Zt).Preliminary communication The most significant factor for controlling root size of red beet is likely to be the density of seed plantings. Most red beet is produced by direct sowing with precision drills at an in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants per m. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. The best in-row seed spacing distribution accuracy was determined at the speed of 0,83 m/s with the pneumatic feed precision drill operated suction system, when 83,1 % of seeds were laid at the 0,5÷1,5 of the theoretical seed spacing. Inferior results were obtained with the belt feed mechanism at an operating speed of 1,81 m/s.

Utjecaj brzine kretanja i tehničkih izvedbi precizne sijačice na preciznost sjetve cikle unutar reda

The most significant factor for controlling root size of red beet is likely to be the spacing between plants, or the density of seed plantings. Most red beet that is used in processing and for the market, is produced by direct sowing with precision drills at an inter-row spacing of 30 to 60 cm and in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants m-2. The desired plant density per unit area can be achieved by using mechanical and pneumatic precision drills, and by sowing calibrated seeds. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. This was prevalent in cases of drills that used mechanical feed mechanisms, rather than drills with pneumatic feed mechanisms. The best in-row seed spacing distribution accuracy was determined at the speed of 0.83 ms-1 with the pneumatic feed precision drill operated suction system, when 83.1% of seeds were laid at the 0.5-1.5 of the theoretical seed spacing (Zt). Inferior results were obtained with the belt feed mechanism at an operating speed of 1.81 ms-1 (63.4% of Zt).Preliminary communication The most significant factor for controlling root size of red beet is likely to be the density of seed plantings. Most red beet is produced by direct sowing with precision drills at an in-row spacing of 5 to 10 cm, aiming at 30 to 70 plants per m. The purpose of this research was to examine the effects of varied forward speed on in-row seed spacing distribution accuracy of red beet using different types of precision drills. It was found that an increase in the drill operating speed decreases drilling precision. The best in-row seed spacing distribution accuracy was determined at the speed of 0,83 m/s with the pneumatic feed precision drill operated suction system, when 83,1 % of seeds were laid at the 0,5÷1,5 of the theoretical seed spacing. Inferior results were obtained with the belt feed mechanism at an operating speed of 1,81 m/s.

Dynamics and deposit of spray droplets disintegrated by the nozzles of a tractor-mounted sprayer

Oil rape is a valuable fodder because in early spring and late autumn it produces green forage used for the nutrition of domestic animals. It has been replacing sunflower and soy in colder and wetter regions. It is additionally advantageous because it leaves behind more nitrogen in soil, which is beneficial to other plants in plant rotation. There are some possible ways for the fixation of nitrogen in soil and they are as follows: by the means of oil rape straw ; by relatively long roots ; by the action of nitrogen bacteria, which perform the nitrogen synthesis within their root system, which is the case in some leguminous plants. Oil seed rape is expected to be wider used in crop rotation of West and Middle Europe, Croatia included. Due to this various sorts have been introduced and potential positive impacts have been studied in order to boost the process. This paper presents information on barley and wheat yield in case when they were sown after oil seed rape and corn. The aim of the research is to determine the presence of positive impacts upon the soil with special attention paid to a potential increase of nitrogen content after oil seed rape was grown. The preceding crops had statistically significant effect. Rape yield was significantly higher compared to the one with corn as preceding crops. Very similar results were obtained in 2007.The maize hybrids seed from three different FAO groups (FAO 400, FAO 500 and FAO 600) in four fractions (KO, KP, SO and SP) produced in two climatically different years (extremely dry 2000 and extremely wet 2001) had been different in quality and chemical composition. The effects of year, genetic specifity and seed fraction at the kernel mass, chemical composition (starch, proteins, cellulose, oil and moisture content) and seed vigour have been evaluated. The influence of agroecological conditions during two production years have been exposed at seed chemical composition and vigour indicators (cold test – CT and bulk seed electrical conductivity - EC). The genetic specificity and seed fraction had significant influence at all tested indices, with the exception of the influence of the fraction at the starch content

Effect of the quantity and size of the droplets in disintegrated spray on wheat leaf coverage

The quantity of droplets has no significant effect on the pesticide coverage at lower and middle working speeds. This is more significant at higher working speeds. The bigger the droplet quantity, the more decreased the coverage. This is due to the additional disintegration of droplets, which produces more evaporated and air drifted droplets, and the rest of them are not sufficient enough to achieve an efficient coverage. The effect of the droplet size expressed as the median diameter is insignificant considering the coverage at lower and middle speeds. In order to achieve more efficient coverage, and especially in the case of the protection against diseases and poorly movable pests in which case the whole plant is being „bathed”, it is necessary to decrease and maintain the working speed within the range of 1.67–2.0 ms−1 (6.0–7.2 kmh−1).

The influence of oilseed rape ripening on the drying process in a dryer

Drying is the oldest but also the most simple way of preservation. Grains are dried to the level of moisture equilibrium. It is well known that different parts of oilseed rape seeds, that have different initial moisture levels, behave in a different way during drying. Bristol, Eurol, and Alaska, which are „ 00” rapeseed cultivars were researched. Bristol and Alaska are French sorts produced by Monsanto S.A.S. Alaska is a German sort produced by KWS. The research was conducted on fields in Zdenci.The mean bootstrap value (“ bootstrap mean” ) of the correlation coefficient was 0.657 ; the bias was 0.00736 ; the standard failure (bootstrap estimation of standard failure) was 0.247 ; a normal 90% bootstrap interval of the correlation coefficient ranged from 0.23589 to 1.00. The real (population) correlation coefficient was higher than zero, i.e. there was a positive correlation between the length of time of the ripening in field and drying in a dryer. A linear regression model, which best describes the linear relation between the length of time of the ripening in field and the length of time of drying in a dryer can be expressed as y =1, 47564 x – 6, 6605. The mean bootstrap regression coefficient value was 1.5024 ; the bias 0.0267 ; the standard failure was 0.7401 ; a normal 90% bootstrap interval of the correlation coefficient ranged from 0.232 to 2.666. The real (population)correlation coefficient was higher than zero, i.e. there was a positive correlation between the length of the ripening in field and the drying in a dryer.