Luka Šumanovac

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

Wheat and Barley Yiels Affected by the Rotation of Oilseed Rape as the Preceding Crop

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.

Analysis of winter wheat yield in the production system based on tramlines (technological tracks)

A comparison of the results related to the yield concerning the experiment settings within the three-year period without and with tramlines proves the hypothesis that the wheat yield increases by 20 or more percent on account of the application of tramlines. The average yield of 7.78 tha−1 achieved by the use of this technology is by 20.62 % higher compared to the yield of 6.45 tha−1 achieved using the conventional wheat growing method, which does not apply tramlines. Yield increase is due to timely and proper fertilization and crop protection, as well as the performance of full-range working operations. The transversal yield variability expressed as s variation coefficient for both settings is significantly lower compared to the variability of a centrifugal spreader, which is in broad use for fertilizing. It is necessary to apply pneumatic spreaders even in the cases when tramlines cannot be used. They distribute fertilizers evenly, and it is well known that this has a decisive influence on high and stable yield. Outstandingly high hectolitre masses and 1,000 grains masses with low variation coefficients showed no significant deviation for both settings. The analysis of the results showed a substantial effect of margin rows on the yield increase related to the setting with tramlines. The average yield was 9.69 tha−1 and it ranged from 8.39 to 12.02 tha−1 in different samples.