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Open access

Milka Brdar-Jokanović, Branka Ljevnaić-Mašić, Dejana Džigurski, Anamarija Koren, Larisa Merkulov-Popadić, Ljiljana Nikolić and Dušan Adamović

Summary

The aim of this study was to examine weed flora occurring in an organic common mallow (Malva sylvestris L.), a newly established crop at the experimental field Bački Petrovac, Institute of Field and Vegetable Crops, Novi Sad, during the growing season of 2014. The weed flora consisted of six species, with even a half being invasive for Vojvodina region (Sorghum halepense, Amaranthus retroflexus, Datura stramonium). The observed low floristic diversity may be related to unbalanced ecological conditions in a newly established crop, invasive species, comparatively low fertilization, allelopathic relations, and possibly robust habitus of the main crop. However, although the flora was low in diversity, both narrow and broadleaf species were represented, with the average infestation as high as 16 individuals per m2. In addition, since the recorded weeds flower from Mart to November, until the development of more efficient methods that are in compliance with the principles of organic agriculture, mechanical weeding should be performed at least three times during the growing season. To our knowledge, this is the first such report on organic common mallow in agro ecological conditions of Serbian province Vojvodina and represents the first step in establishing the adequate weed control measures.

Open access

Marina Štukelj and Jan Plut

Summary

African swine fever (ASF) is a serious disease of domestic and feral swine mainly because of grave clinical course of the disease and its strong socio-economic impact. Not only there is an extremely high mortality (95–100%) around the time of the first outbreak, live-animal, pork meat and other pork product trade is strongly affected on regional and international level. ASF is a species-specific disease; strength of the clinical signs depends on virulence of a viral strain. Exacerbation of body temperature and dysfunction of respiratory system and gastrointestinal tract are most common occurrences. Lesions can be mostly classed as congestive or hemorrhagic. Epidemiologically, ASF varies substantially among regions, countries and continents due to wide panel of different virus genotypes, population of feral swine and other reservoirs of disease, geographical characteristics and social habits of people. ASF is endemic in Sub-Saharan Africa where soft ticks (Argaside) and chronically infected feral swine population serve as reservoirs. It also became endemic in most parts of Russian Federation. Since 1978, ASF is endemic on Sardinia isle, as it was eradicated in all other parts of Europe. First outbreak in Georgia in 2007 has apparently served for transmission to other eastern European countries. Slovenia is currently still ASF-free but disease has already reached some relatively nearby countries (Poland, Romania, Moldova, Czech Republic and Hungary). There is no anti-ASF vaccine currently available ad specific treatment has not been described. Therefore rapid diagnostics and implementation of strict biosecurity measures play a key role in prevention of further transmission.

Open access

Christoph Husemann, Vesna Rodić and Jovana Husemann

Summary

Phosphorus is an essential nutrient for all forms of life, which means that food cannot be produced without it. As the phosphate rock (concentrated source of phosphorus) is a non-renewable and finite resource, with no substitute, without more sustainable management of phosphorus its deposits could be depleted in a rather short period. In addition, much of phosphorus eventually ends up in environment, where it causes pollution. Hence, one could say that the lack of phosphorus and its inappropriate management could be a bottleneck for a sustainable food supply and agricultural development in general. Nevertheless, unlike some other challenges that modern agriculture has to face (for example, water and energy scarcity, climate changes etc) the problem of phosphorus limited availability and accessibility has been largely neglected until recently. This paper’s particular intention is to explain why phosphorus management is one of key issues for the sustainable food supply and agricultural development, which factors have to be considered when dealing with this topic and which technologies could be applied as potential solutions. One solution to become independent from the fossil deposits of phosphorus might be its extraction from wastewater, which could contribute significantly to overcome the looming phosphorus and growing environmental crisis.

Open access

Jelena Golijan, Aleksandar Popović and Ljubiša Živanović

Summary

Over the past few years, organic agricultural production has increased globally. This type of production is regulated by numerous laws and concomitant regulations, whereas the basic principles of organic production development are prescribed by the IFOAM standards and the European Union. Seed production is of immense importance to organic agricultural systems as the use of certified seed is crucial in preserving organic production. Prior to 2009, certified organic seed had not been produced in the Republic of Serbia, and producers had used either landrace seeds or chemically untreated conventional seeds. Of the total area devoted to organic farming in the Republic of Serbia (14,357.96 ha), seed production accounts for only 8.4 ha, with uneven distribution over regions. The highest organic seed production (5.2 ha) has been recorded in the region of Vojvodina. However, there is still a lack of certified organic seed in the country, emphasizing the need for organic seed breeding and production in the future.

Open access

Lida Issazadeh, Mustafa Ismail Umar, Said I.A. Al-Sulaivany and Jian Hassanpour

Summary

Estimating soil hydraulic properties are so important for hydrological modeling, designing irrigation-drainage systems and soil transmission of soluble salts and pollutants, although measurements of such parameters have been found costly and time-consuming. Owing to a high spatial variability of soil hydraulic characteristics, a large number of soil samples are required for proper analysis. Nowadays, geostatistical methods are used to estimate soil parameters on the basis of limited data. The purpose of this research is to investigate the spatial variability of the permeability coefficient in different soil textures (26 soil samples) found in the Kurdistan region of Iraq. The parameter values obtained indicated a normal trend in particle size distribution, whereas the values of permeability coefficient showed aberrant distribution patterns. Geostatistical analysis results indicated the best fitted theoretical model was Gaussian model and the proportion of sill/(sill + nugget) was 0.17 indicated strong spatial dependency of soil permeability. Furthermore, the optimal distance for estimating the soil permeability coefficient was 109,119 meters. A comparison of the kriging and IDW interpolation methods showed that both methods can estimate soil permeability with high accuracy and less error. The prediction maps of the applied methods indicated that high soil permeability rates were recorded in the south-east of the Kurdistan region of Iraq compared to low soil permeability rates recorded in the remainder of this region. It is recommended other interpolation methods such as co-kriging and indicator or simple kriging methods could be used to simulate data in large scale areas as well.

Open access

Mostafa Mamdouh Elshenawy, Galal Bakr Anis, Walid Hassan Elgamal and Ebrahim Abd-Elsalam Ramadan

Summary

Line × Tester experiment was carried out at the Experimental Farm of Rice Research and Training Center (RRTC), Sakha, Kafrelsheikh, Egypt during three growing seasons to evaluate the performance of 21 F1 hybrids along with their parents. Three cytoplasmic male sterile lines, two wild abortive (Wild Abortive); IR69625A, IR70368A and one (Kalinga) K17A as female were tested with seven cultivars/lines as testers. The analysis of variance detected that, highly significant variations among genotypes (parental lines with their crosses) for all traits in both seasons and in their combined analysis. Two hybrid combinations; IR69625A×Giza178 and IR69625A×Giza179 were recorded the best values for grain yield under both seasons and their combined. General combining ability (GCA) and specific combining ability (SCA) effects of genotypes for the studied traits were estimated. The results indicated that, K17A (female) and Giza 179 (male) were the best combiner for early heading date and could be useful to breed early maturing rice cultivars. The CMS line IR69625A and Giza178, Giza179 gave highly significant and positive GCA value and so appeared to be good parental lines combiner in hybrid combinations for high grain yield/plant. The positive values of GCA mean increased for grain yield/plant, which could be useful in breeding programs for high yield potential rice cultivars. The hybrid combination IR69625A×Giza179 showed highly significant and positive SCA estimates under both seasons and their combined. In conclusion, it is clear that this hybrid seemed promising hybrid for earliness and high grain yield under Egyptian conditions.

Open access

Borivoj Pejić, Ksenija Mačkić, Predrag Randjelović, Ivan Valtner, Jelica Gvozdanović-Varga and Atila Bezdan

Summary

The objective of this study, conducted in the northern Serbian province of Vojvodina, was to analyze the effect of surface and subsurface drip irrigation (with drip lateral placement depths of 0.05 and 0.1 m) on the yield and water productivity of onions (Allium cepa L., var. ‘Holandski žuti’). The irrigation applied was scheduled on the basis of the water balance method. The daily evapotranspiration rate was computed using the reference evapotranspiration (ETo) based on the Hargreaves equation and the crop coefficient (kc). The irrigation rate was 30 mm, whereas the amount of water added by irrigation during the season was 150 mm. According to the results obtained, the onion yield under irrigated conditions was significantly higher than that under non-irrigated (control) conditions. Differences in the yield obtained using surface and subsurface irrigation were non-significant. The amounts of water used for evapotranspiration under irrigated and non-irrigated conditions were 363 mm and 220 mm, respectively. The value of the surface irrigation yield response factor (Ky) was 0.62, whereas the values of the subsurface irrigation yield response factor (Ky) were 0.61 (0.05 m) and 0.79 (0.1 m). Consequently, onions grown from sets proved moderately sensitive to water stress under regional climate conditions and could be grown without irrigation. The value of the irrigation water use efficiency (Iwue) ranged from 3.55 to 4.97 kg m−3, whereas the value of the evapotranspiration water use efficiency (ETwue) ranged from 3.72 to 5.22 kg m−3. The highest yield of onions was obtained using a drip lateral placement depth of 0.1 m, which is recommended for high-yielding onion production.

Open access

Milan Jocković, Petar Čanak, Vladimir Miklič, Jelena Ovuka, Velimir Radić, Siniša Jocić, Sandra Cvejić and Ana Marjanović-Jeromela

Summary

A useful approach for improving seed germination and seedling growth is a seed priming technique. Application of the priming technique enhances water absorption, causing activation of metabolic activities in the seed. The objective of this study was to evaluate the effect of seed priming on germination parameters of safflower and to compare different priming techniques: priming by soaking and priming on filter paper. The priming treatments included hydropriming (distilled water) and osmopriming with 0.1% and 0.5% solutions of KNO3 for 8 and 16 hours. The experiment revealed significant difference between the priming treatments and the control. The highest germination (89.50%) was recorded within the priming treatments by soaking in the solution of 0.1% KNO3 and priming on filter paper moistened with 0.5% KNO3 for 8 hours. Considering germination index, mean germination time and time to 50% germination, the best results were obtained within hydropriming on filter paper for 16 hours. This study has shown that the priming techniques significantly improved germination parameters of safflower. Although priming on filter paper showed better results, the soaking technique – due to its simplicity, low cost and easiness of application – can be successfully used to improve germination parameters of safflower and increase the number of plants per unit of area and thus increase the seed yield per acreage.

Open access

Mirko Ivković, Jelena Stanivuk, Branko Jakovljević, Siniša Bjedov and Dušan Rajković

Summary

In a total mixed ration (TMR) feeding system, lambs, as well as other animals, tend to exhibit dietary preferences. The purpose of this paper is to examine differences in the feed selection behavior between lambs previously accustomed to TMR feeding and lambs newly introduced to TMR diets.

A total of eight male Suffolk lambs were allocated to two groups of four each. Both groups received the same feed formulation. The roughage portion of the diet consisted of alfalfa hay, whereas the concentrate portion included a concentrate mixture for finishing lambs. One group of lambs was fed total mixed rations containing 30% alfalfa hay and 70% pelleted concentrate. The other group received alfalfa hay and concentrate rations separately as single diets. Diet selection measurements were performed after four weeks of the experimental feeding regime.

The results obtained indicate a clear preference of both groups for concentrate (112±5% and 110±6% respectively) over alfalfa hay (72±11% and 77±14% respectively). Significant differences were recorded in the duration of feeding time. The lambs accustomed to TMR feeding consumed 400 g of TMR for 18±1 minutes, whereas the lambs newly introduced to TMR diets required 154±88 minutes for the same allotment. Moreover, the lambs starting on a TMR diet were found to consume feed markedly slower, although their diet selection proved equally successful compared to the lambs accustomed to TMR feeding.

Open access

Zoran Ristić, Slobodan Puzović, Igor Ponjiger, Miroslav Urošević, Milutin Kovačević, Milosava Matejević and Vladimir Marković

Summary

Decrease of grey partridge population is a global process that has been catastrophic in recent decades. In England, the number of this species declined by 80% in the period from the beginning of the fifties to the mid-eighties of the last century (Potts, 1986). In the Czech Republic from 1965 to the end of the eighties by as much as 95% (Štasny et al. 1997), and the situation is similar in Poland (Panek, 2005). The status of grey partridge in Serbia follows the same pattern as mentioned, with drastic decline (Ristić and Puzović, 2015). The reasons for such trend are numerous, directly conditioned and are often difficult to eliminate. It has been found that culling has no significant effect on the population (Ristić, 1992), but changes in its habitat in order to increase the yield of agricultural crops and chemical protection have very negative effect on partridge number. In order to study each type of game, it is necessary to know the basic elements of the population: density, growth, birth rate, mortality, migration movements and gender and age structure. Migration has no effect on changes in the partridge populations. Period of assessment 2010-2013: Serbia: 20,000-28,000 breeding pairs (bp), Vojvodina: 900-1,000 bp. Long-term population trend 1980-2003: MD (mean decrease in number), short-term population trend 2000-2013: MD (mean decrease in number). The number generally decreases, especially in Vojvodina, where it is endangered by intensive agriculture and the application of harmful biocides. It is necessary to improve the monitoring and develop the national action plan.