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Constraints and prospects for apiculture research and development in Amhara region, Ethiopia Texto completo
2009
Ejigu, K. | Gebey, T. | Preston, Thomas R.
Ethiopia has been amongst the principal honey and beeswax producers worldwide for centuries. Beekeeping in Amhara region could be one way of assisting millions of the region’s farmers to improve their cash income, provide additional food, assist in pollination, generate employment and at the same time produce honey, beeswax and other hive products which can bring foreign currency into the country. This paper discusses the constraints and the future prospects on apiculture development of the region. The challenges are many but can be overcome while the opportunities are very encouraging. As a conclusion, developing appropriate policy and beekeeping development strategy that would be applicable to the different production systems will ensure the sustainable development of apiculture sub sector.
Mostrar más [+] Menos [-]Reproductive performance of traditionally managed sheep in the south western part of Ethiopia Texto completo
2009
Berhanu, Belay | Haile, Aynalem
The study was conducted to assess the reproductive performance of ewes under village management condition in south western part of Ethiopia. The study was a monitoring study which took place for three years (1995-1997). The overall least squares means for lambing interval (LI) and annual reproductive rate (ARR) were 262 ±53.4 days and 1.88 ± 0.44, respectively. The overall least squares means of age at first lambing and litter size were 404 + 65.40 day and 1.21+1.45 lambs, respectively. Lambing interval was significantly (P<0.05) influenced by parity of the ewe, type of birth and year of lambing. The ewes at their first, and six and above parity showed longer subsequent lambing interval than ewes at 2-5 parity. Ewes that suckled singles had shorter subsequent lambing interval than ewes which suckled twins (255+3.74 vs 283+5.72 days). Year of lambing and type of birth exerted a significant effect (P<0.05) on ARR. The ewes that dropped twins had higher ARR than ewes which dropped singles (1.52 Vs 2.56 lambs/ewe/year). Litter size was significantly (p<0.05) influenced by season of lambing and parity of the ewe. There was a tendency that, litter size increased with an increase of parity up to fifth parity and dropped at the sixth and more parities. The reproductive performance of ewes under village management condition is discussed in association with reports elsewhere in the tropics.
Mostrar más [+] Menos [-]Characteristic of grain quality for early generation lines in the crossings between covered and hull-less barley Texto completo
2009
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia) | Belicka, I., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine effect of hull-less gene on grain quality traits (crude protein, starch and β-glucans) and to evaluate the heritability of these traits in the F4 and F5 generations of six crosses between covered and hull-less barley (Hordeum vulgare L.). The trial was carried out at the State Stende Cereal Breeding Institute during the years 2007 and 2008. Mean value, range and the coefficient of variation of traits for covered and hull-less lines within each cross combination were calculated. Heritability of quality traits was estimated as intergeneration correlation (r) and linear regression coefficients (b). The highest intergeneration correlation values were observed for starch content within covered and hull-less barley populations (rF4:F5=0.609 and 0.635 respectively). Moderate intergeneration relationship was observed for crude protein content within covered barley population (r=0.582), and for β-glucans content within hull-less barley population (r=0.593). The regression estimates of heritability were higher for starch content for both covered and hull-less barleys (b=0.549 and 0.703 respectively). Due to effects of genotype and environment interactions the regression estimates of heritability for crude protein and β-glucans content for both covered and hull-less barley were low (b varied from 0.347 to 0.373).
Mostrar más [+] Menos [-][Factors that influence the starch content in winter rye] Texto completo
2009
Poisa, L., Latvia Univ. of Agriculture, Jelgava (Latvia);Agricultural Science Centre of Latgale, Vilani, Rezekne reg. (Latvia)
The EU Directive on the promotion of the use of biofuels or other renewable fuels for transport (CO M 2003/30/EC) states that the proportion of biofuels in 2010 must make 5.75% of non-renewable fuels, but in 2020 - 10%. The only way for Latvia to fulfil the Directive 2003/30/EC is to use winter rye because it is one of the oldest cereals grown in Latvia, and Latvia has a long-lasting experience in growing it. A field trial of winter rye (Secale cereale L.) was arranged in the Agricultural Science Centre of Latgale from 2005 to 2007. The influence of four winter rye varieties and five fertilizer rates on grain yield and starch content was researched for three years. The year (factor A), the varieties (factor B), the fertilizer rates (factor C), and the interaction of factors AB, AC , BC, and ABC significantly influenced the yield of grain and the starch content with 95% probability. It is recommended to use good quality grain with high starch content and low protein content for bioethanol production. The varieties of winter rye 'Kaupo', 'Amilo', and 'Walet' are the most suitable for ethanol production in Latgale region.
Mostrar más [+] Menos [-]Influence of agroecological factors on winter oilseed rape (Brassica napus L.) autumn growth Texto completo
2009
Balodis, O., Latvia Univ. of Agriculture, Jelgava (Latvia)
Sowing area under oil-seed rape (Brassica napus L.) has increased during last decade in Latvia and has become more or less stable since 2007. Lack of research on impact of sowing date, sowing rate, fungicide as growth regulator application and other agroecological factor issues on rape autumn growth is observed. The aim of our research, started in autumn 2007 in Research and Study farm Vecauce, was to investigate the influence of applied agroecological factors (five sowing dates, four sowing rates and fungicide (as growth regulator in autumn) application on two type winter rape varieties development in autumn. Winter rape biometrical parameters, dry matter content and dry mass per square m of leaves were estimated. Sowing date affected height of growth point, root neck diameter, plant and root mass, main root length significantly (p is less than 0.05). Sowing rate affected only some indices significantly in autumn 2007. Fungicide (juventus 90 s.c. - metconasol 90 g LE-1) application also affected rape plant biometric parameters during autumn depending on conditions of research year - height of growth point decreased only in year 2007, effect on number of leaves per plant was observed in both trial years, plant weight (2007) and root length (2008) were affected for hybrid variety. Sowing date showed effect on dry matter content in leaves as well as on dry matter mass of leaves per 1 square m. Fungicide application increased dry mass of leaves per 1 square m in two earlier sowing dates. Results are important also for outline of further research directions evaluating significance of above mentioned factors for winter rape wintering in Latvia.
Mostrar más [+] Menos [-]The impact of soil penetration resistance on winter wheat yield and development Texto completo
2009
Dinaburga, G., Latvia Univ. of Agriculture, Jelgava (Latvia)
Formation of yield in crop cultivation is affected by influence of many factors. Simple summation of individual factors is quite rare occasion. Interaction among factors is a dynamic value. The effect of interactions varies depending on the crop development stages as well as by graduation of factors. The study aimed to evaluate the soil penetration resistance effect on winter wheat grain yield and development. It allows specifying recommendations for soil treatment difference criteria for use in site-specific soil tillage. Field trials were carried out at the Research and Study farm Vecauce of Latvia University of Agriculture during the years 2005-2007 to investigate factors influencing formation of winter wheat grain yield. Forty seven points (distributed as grid 50x50 m) were selected in the winter wheat Triticum aestivum L. field. All points were attached to their geographic coordinates. Data shows significant effect of soil resistance to grain yield - increase of soil penetration resistance by 100 kPa cmE-2 reduced yield of winter wheat by 0.37 to 0.48 t haE-1. By contrast in 2007 a significant linear regression relationship between soil penetration resistance and the yield was not detected. Differences of fresh weight of winter wheat plants in tillering stage and the beginning of stem elongation were insignificant compared to different groups of soil penetration resistance at soil layers 0.10-0.30 m in both experimental years. Higher impact of soil penetration resistance on flag leaf area difference had soil resistance at the layer of 0.20 - 0.30 m and differences were significant in both trial years.
Mostrar más [+] Menos [-]Removal of nitrogen, phosphorus and potassium with summer pruning of apple trees Texto completo
2009
Surikova, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Karklins, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of the research was to study the removal of nitrogen, phosphorus and potassium with summer-pruned branches of apple-trees grown on dwarfing rootstocks under the influence of applied moisture regulation methods. The investigation was done at the Latvia State Institute of Fruit-Growing in Dobele, on the basis of an existing field experiment planted in 1997 with cultivar 'Melba' (rootstock B9) at 1.5 - 4 m trees spacing distances. Three different treatments of soil moisture management were compared: control (without moisture regime regulation), sawdust mulch and fertigation. Inter-row strips were covered by grass vegetation (Lolium perenne L. and Poa pratensis L., in proportion 1:3). Pruning of apple-trees was done in mid-July. The results of the research showed that the applied soil water regulation treatments (mulch and fertigation) had significant influence (p is less than 0.05) on the apple-tree biomass (leaves, one-year and older wood) removed by summer pruning, as well as on the content of dry matter in biomass. The contents of N and K were influenced both by the treatment and age of tree vegetative parts, but the content of P did not differ significantly among treatments or tree parts (p is greater than 0.05). Removal of N with summer-pruned leaves and branches was 30 kg haE-1 N in the mulch treatment and 16 - 17 kg haE-1 in control and fertigation treatments (p is less than 0.05). Removal of K in the control treatment was 19 kg haE-1, in the mulch treatment 40 kg haE-1, but in the fertigation treatment 27 kg haE-1 (p is less than 0.05). Removal of P varied from 5.04 to 9.84 kg haE-1, no significant differences were found among treatments (p is greater than 0.05).
Mostrar más [+] Menos [-]Effects of irrigation and woodchip mulch on growth and habit of sour cherries Texto completo
2009
Feldmane, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
Sour cherries become more popular due to their food value. Therefore sour cherries could be a profitable crop for fruit growers in Latvia. Information about sour cherry response to soil moisture adjustment is needed, because based on previous studies it is not possible to predict the influence of irrigation and mulch on sour cherry growing. The trial was carried out at the Latvia State Institute of Fruit Growing in 2007 to determine the effect of soil moisture adjustment on the growth of different sour cherry cultivars. Woodchip mulch and drip irrigation were used as main factors, cultivars 'Bulatnikovskaya', 'Desertnaya Morozovoi', 'Latvijas Zemais', 'Orlica', 'Shokoladnica', 'Tamaris', 'Zentenes' were used as a secondary factor. Vegetative growth, branching angles of lateral shoots, proportions of pruned shoots, spurs and twigs were determined to characterize the response of cultivars to mulching and irrigation. In general use of drip irrigation increased vegetative growth of sour cherries, but the use of woodchip mulch decreased this growth. Branching angles were wider in variant with woodchip mulch. Cultivar 'Zentenes' most positively responded to use of woodchip mulch and drip irrigation.
Mostrar más [+] Menos [-]Evaluation of winter hardiness and productivity of five highbush blueberries cultivars in Latvia Texto completo
2009
Sterne, D., Latvia Univ. of Agriculture, Jelgava (Latvia) | Abolins, M., Latvia Univ. of Agriculture, Jelgava (Latvia)
Winter hardiness is very important for introducing and commercial cultivation of blueberries in North Europe. Winter survival in the field is influenced by multiple factors that are influenced by uncontrollable environmental parameters. In the years 2006-2008, in eight farms were surveyed in different fruit-growing areas of Latvia, which produce highbush blueberries. We were interested in the plants physiological conditions (winter hardiness) after the winter, yields and the growth conditions. All study sites were evaluated by 6-year-old plant of highbush blueberry cultivars 'Polaris', 'Chippewa', 'Patriot', 'Northblue' and 'Duke'. After the year 2006/2007, the highest winter hardiness was observed for 'Polaris', 'Chippewa', 'Northblue' and 'Patriot'. The lowest winter hardiness was observed in 'Duke'. December 2007, January and February 2008 changing weather conditions did not do significant damage in plantations. 'Patriot' and 'Chippewa' had the highest average yield (kg per bush) throughout the production period, cultivar 'Northblue' had the lowest yield. On the other hand, 'Northblue' had the highest 100 berry weight. Cultivar 'Patriot' had the largest berry size - most of the berries had a diameter of 15 - 16 mm.
Mostrar más [+] Menos [-]Development and situation of trout culture in Turkey Texto completo
2009
Canyurt, M.A., Ege Univ. (Turkey) | Akhan, S., Rize Univ. (Turkey)
The production of rainbow trout (Oncorhynchus mykiss) is developing and it is most cultured finfish species in Turkey. It was first introduced in Turkey in the mid 1970s from Italy. In the following years, culture studies of native trout strains, mainly Black Sea trout; Salmo trutta labrax and Abant Lake trout, Salmo trutta abanticus started in late 1990. Market size trout production was performed in two main categories, inland areas (mainly concrete ponds by flow through fresh water and cages) and in sea (offshore cages). Total trout production was 61.173 tons in 2007.
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