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Mikkeli, Finland

Horn L.N.,University of KwaZulu - Natal | Horn L.N.,Plant Production Research | Ghebrehiwot H.M.,University of KwaZulu - Natal | Shimelis H.A.,University of KwaZulu - Natal
Frontiers in Plant Science | Year: 2016

Cowpea (Vigna unguiculata [L.] Walp.) yields are considerably low in Namibia due to lack of improved varieties and biotic and abiotic stresses, notably, recurrent drought. Thus, genetic improvement in cowpea aims to develop cultivars with improved grain yield and tolerance to abiotic and biotic stress factors. The objective of this study was to identify agronomically desirable cowpea genotypes after mutagenesis using gamma irradiation. Seeds of three traditional cowpea varieties widely grown in Namibia including Nakare (IT81D-985), Shindimba (IT89KD-245-1), and Bira (IT87D-453-2) were gamma irradiated with varied doses and desirable mutants were selected from M2 through M6 generations. Substantial genetic variability was detected among cowpea genotypes after mutagenesis across generations including in flowering ability, maturity, flower and seed colors and grain yields. Ten phenotypically and agronomically stable novel mutants were isolated at the M6 each from the genetic background of the above three varieties. The selected promising mutants’ lines are recommended for adaptability and stability tests across representative agro-ecologies for large-scale production or breeding in Namibia or similar environments. The novel cowpea genotypes selected through the study are valuable genetic resources for genetic enhancement and breeding. © 2016 Horn, Ghebrehiwot and Shimelis. Source

Partanen K.,Animal Production Research | Siljander-Rasi H.,Animal Production Research | Karhapaa M.,Animal Production Research | Ylivainio K.,Plant Production Research | Tupasela T.,Biotechnology and Food Research
Livestock Science | Year: 2010

A performance trial was carried out with 117 growing barrows (25-65kg) to study the effects of different levels of dietary phosphorus (P) on the pigs' performance and bone characteristics and on the content and solubility of P in faeces. Isoenergetic diets (9.0MJNEkg-1) were used containing 0.10, 0.55, 1.00, 1.45, 1.90, and 2.35% of monocalcium phosphate, and a constant calcium (Ca) to P ratio of 1.2:1. The analysed total P content ranged from 4.1 to 9.5gkg-1. The diets were calculated to contain 1.6, 2.5, 3.5, 4.5, 5.5, to 6.5gkg-1 of nonphytate P, respectively. The diet with the lowest nonphytate P content resulted in slightly lower average daily gain than the diets with ≥2.5gkg-1 of nonphytate P. The feed to gain ratio was increased when the diets contained more than 3.5gkg-1 of nonphytate P. The bending moment of rib and metacarpal bones was increased until the nonphytate P content reached 4.5 and 2.5gkg-1 feed, respectively, while 4.5gkg-1 of nonphytate P was required to maximise the Ca and P content of metacarpals. In accordance with the Hedley fractionation, the amount of water-soluble P was not affected by increased dietary phosphate content, but the amounts of NaHCO3-, NaOH-, and HCl-soluble P fractions increased. In conclusion, the nonphytate P content of 2.5gkg-1 feed was recommended for growing pigs of 25-65kg body weight. © 2010 Elsevier B.V. Source

Lotjonen T.,Plant Production Research | Isolahti M.,Boreal Plant Breeding Ltd.
Acta Agriculturae Scandinavica Section B: Soil and Plant Science | Year: 2010

The goals of the study were to explore the suitability of direct drilling for Nordic soil and climatic conditions, the suitability of manure use in direct drilling, and the availability of direct drilling after a ley period. In spring 2003, two direct drilling experiments were established on fine sand and organic soils in northern Finland. In the three-year experiments, autumn and spring ploughing were compared with direct drilling. The crop was spring barley (Hordeum vulgare L.) each year, and it was fertilised with cattle slurry or artificial fertiliser. In the first experiment the previous crop was always cereal and in the second experiment it was always ley. Direct-drilled barley normally produced yields as high as those for ploughed barley (3500-5000 kg/ha). In some years, the hectolitre weight and thousand-grain weight of the direct-drilled barley were a little lower compared with those for the ploughed barley, but not in others. These results are very similar to the results of previous direct drilling experiments done in clay soils in southern Finland and in Scandinavia. Slurry spread before direct drilling probably lost part of its soluble nitrogen, because the yield of direct-drilled barley that was fertilised with slurry was in two years 20-40% lower than that of ploughed barley. The direct drill machine did not mix the slurry and the soil sufficiently. Controlling Elymus repens L. (common couch) was also very important in direct drilling. If E. repens was not controlled every year, the yield of direct-drilled barley decreased by more than 40% in the second year. When the ley period was ended properly by treating with glyphosate, direct drilled barley yields were good. We can conclude that direct drilling is a suitable method for Nordic soil and climatic conditions, if perennial weeds or old ley are controlled chemically and manure is mulched beforehand. © 2010 Taylor & Francis. Source

Cooke L.R.,Agri Food and Biosciences Institute of Northern Ireland | Schepers H.T.A.M.,Wageningen University | Hermansen A.,Norwegian Institute for Agricultural And Environmental Research Bioforsk | Bain R.A.,SAC | And 11 more authors.
Potato Research | Year: 2011

Phytophthora infestans, the causal agent of late blight, is a major threat to potato production in northwestern Europe. Before 1980, the worldwide population of P. infestans outside Mexico appeared to be asexual and to consist of a single clonal lineage of A1 mating type characterized by a single genotype. It is widely believed that new strains migrated into Europe in 1976 and that this led to subsequent population changes including the introduction of the A2 mating type. The population characteristics of recently collected isolates in NW Europe show a diverse population including both mating types, sexual reproduction and oospores, although differences are observed between regions. Although it is difficult to find direct evidence that new strains are more aggressive, there are several indications from experiments and field epidemics that the aggressiveness of P. infestans has increased in the past 20 years. The relative importance of the different primary inoculum sources and specific measures for reducing their role, such as covering dumps with plastic and preventing seed tubers from becoming infected, is described for the different regions. In NW Europe, varieties with greater resistance tend not to be grown on a large scale. From the grower's perspective, the savings in fungicide input that can be achieved with these varieties are not compensated by the higher (perceived) risk of blight. Fungicides play a crucial role in the integrated control of late blight. The spray strategies in NW Europe and a table of the specific attributes of the most important fungicides in Europe are presented. The development and use of decision support systems (DSSs) in NW Europe are described. In The Netherlands, it is estimated that almost 40% of potato growers use recommendations based on commercially available DSS. In the Nordic countries, a new DSS concept with a fixed 7-day spray interval and a variable dose rate is being tested. In the UK, commercially available DSSs are used for c. 8% of the area. The validity of Smith Periods for the new population of P. infestans in the UK is currently being evaluated. © 2011 The Author(s). Source

Hellstrom J.K.,Mtt Agrifood Research Finland | Shikov A.N.,Interregional Center Adaptogen | Makarova M.N.,Interregional Center Adaptogen | Pihlanto A.M.,Mtt Agrifood Research Finland | And 5 more authors.
Journal of Functional Foods | Year: 2010

The blood pressure-lowering properties of lyophilized chokeberry juice and polyphenols were monitored using in vitro angiotensin-converting enzyme (ACE) inhibition measurement and a 10day in vivo study with spontaneously hypertensive rats (SHR). Juice and polyphenols indicated weak ACE-inhibitory activity. The IC50 values for polyphenols and juice were 1.5-2.5 and 4.5mg dry matter/ml, respectively. In the SHR study the blood pressure-lowering effects of juice and polyphenol extract seemed to be short-term and were generally highest after 3h from administration (50mg/kg/day) when mean reductions in systolic blood pressure were 20±8 and 15±7mmHg, respectively. Corresponding mean decreases in diastolic blood pressure were 23±6 and 13±2mm Hg in juice and polyphenol groups, respectively. It was concluded that both chokeberry juice and polyphenols had blood pressure-lowering effects. We hypothesize that chokeberry polyphenols enhance endothelial nitric oxide production with an ACE-independent mechanism, e.g. by activation of endothelial nitric oxidase enzyme; this is yet to be verified. © 2010 Elsevier Ltd. Source

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