Jan Eric Jessen, T. Sveinsson, S. Scully, Johann Orlygsson
RANNIS, (Technology Development Fund) (BioFuel), grant number RAN091016-2376 Research Fund of the University of Akureyri
ranis(技术发展基金)(生物燃料)，资助号RAN091016-2376阿库雷里大学研究基金
{"title":"Ethanol production by a Paenibacillus species isolated from an Icelandic hot spring - production yields from complex biomass.","authors":"Jan Eric Jessen, T. Sveinsson, S. Scully, Johann Orlygsson","doi":"10.16886/IAS.2015.02","DOIUrl":"https://doi.org/10.16886/IAS.2015.02","url":null,"abstract":"RANNIS, (Technology Development Fund) (BioFuel), grant number RAN091016-2376 \u0000Research Fund of the University of Akureyri","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"28 1","pages":"15-24"},"PeriodicalIF":0.5,"publicationDate":"2015-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Einarsson, E. Eythórsdóttir, Chris C. R. Smith, J. V. Jónmundsson
The heritability of yield predictions obtained from video image analysis (VIAscan®) of lamb carcasses (n=18,680) and EUROP classes obtained by abattoir assessors (n=26,795) was estimated, as well as the genetic and phenotypic correlations between VIAscan® traits and in vivo lamb traits (n = 9,930), including ultrasonic measurements, visual conformation score and length of the cannon bone. The main objective of the study was to test the equivalence of EUROP classes obtained by VIAscan® and visual scoring as selection criteria in the breeding work. Genetic correlations between EUROP scores from VIAscan® and from abattoir assessors were 0.94 for conformation and 0.82 for fat score. The heritability of conformation score was 0.32 and 0.35 based on VIAscan® and visual scoring, and 0.29 and 0.31 for the fat score, respectively. Yield predictions as proportions of lean meat of carcass weight from VIAscan® were highly heritable, h 2 ranging from 0.39 to 0.63. Lean meat yield (LMY) estimated as lean weight in major cuts had a direct heritability ranging from 0.17 to 0.21, maternal heritability ranging from 0.09 to 0.11 and a common environmental (c 2 ) effect of 0.22-0.23. Lean meat yield of the whole carcass (LMY_%) had the highest genetic correlation to visual leg score (0.44) while correlations between lean yield of three carcass parts (LegY_%, LoinY_% and ShoulderY_%) and in vivo measurements were low to moderately high and favourable except for loin yield. The EUROP scores obtained by both methods had similar genetic and phenotypic correlations to in vivo traits where conformation scores were highly correlated to visual scores for legs and shoulders and ultrasonic muscle measurements and fat scores were positively correlated to ultrasonic fat measurements and shoulder scores. It is concluded that VIAscan® can be used as a grading tool for the Icelandic sheep industry and measurements of carcass traits obtained from the system would be useful in the national sheep breeding program.
{"title":"Genetic parameters for lamb carcass traits assessed by video image analysis, EUROP classification and in vivo measurements.","authors":"E. Einarsson, E. Eythórsdóttir, Chris C. R. Smith, J. V. Jónmundsson","doi":"10.16886/IAS.2015.01","DOIUrl":"https://doi.org/10.16886/IAS.2015.01","url":null,"abstract":"The heritability of yield predictions obtained from video image analysis (VIAscan®) of lamb carcasses (n=18,680) and EUROP classes obtained by abattoir assessors (n=26,795) was estimated, as well as the genetic and phenotypic correlations between VIAscan® traits and in vivo lamb traits (n = 9,930), including ultrasonic measurements, visual conformation score and length of the cannon bone. The main objective of the study was to test the equivalence of EUROP classes obtained by VIAscan® and visual scoring as selection criteria in the breeding work. Genetic correlations between EUROP scores from VIAscan® and from abattoir assessors were 0.94 for conformation and 0.82 for fat score. The heritability of conformation score was 0.32 and 0.35 based on VIAscan® and visual scoring, and 0.29 and 0.31 for the fat score, respectively. Yield predictions as proportions of lean meat of carcass weight from VIAscan® were highly heritable, h 2 ranging from 0.39 to 0.63. Lean meat yield (LMY) estimated as lean weight in major cuts had a direct heritability ranging from 0.17 to 0.21, maternal heritability ranging from 0.09 to 0.11 and a common environmental (c 2 ) effect of 0.22-0.23. Lean meat yield of the whole carcass (LMY_%) had the highest genetic correlation to visual leg score (0.44) while correlations between lean yield of three carcass parts (LegY_%, LoinY_% and ShoulderY_%) and in vivo measurements were low to moderately high and favourable except for loin yield. The EUROP scores obtained by both methods had similar genetic and phenotypic correlations to in vivo traits where conformation scores were highly correlated to visual scores for legs and shoulders and ultrasonic muscle measurements and fat scores were positively correlated to ultrasonic fat measurements and shoulder scores. It is concluded that VIAscan® can be used as a grading tool for the Icelandic sheep industry and measurements of carcass traits obtained from the system would be useful in the national sheep breeding program.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"28 1","pages":"3-14"},"PeriodicalIF":0.5,"publicationDate":"2015-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soil nematodes are a key group that can both influence and reflect changes in the soil ecosystem. We investigated the generic composition, abundance and community structure of soil nematodes in two contrasting vegetation successional seres now found on the 50 year old volcanic island of Surtsey, Iceland. One represented the primary succession without much external input of nutrients (S1), while the other was a grassland that has evolved under a strong influence of allochthonous nutrient inputs by gulls (S2). In 2012 in total 25 genera of nematodes were identified, of which 14 were reported on Surtsey for the first time. Across the whole island, the nematode abundance and distribution was most strongly related to soil C:N ratio, soil acidity, plant cover and biomass. The nematode abundance was higher at S2 and there the trophic structure was dominated by bacterialand plantfeeders, while hyphal-feeders were more dominant at S1. Nematode communities have continued to change at S1 since the last nematode survey, which took place 17 years ago, even where the vegetation cover and composition has remained stable. This may indicate a gradual change in the soil environment at S1. Within S2, the nematode community had become denser and more structured, but still it had lower generic diversity than found at S1. Resource availability was found to be an important driver for nematode colonization and primary succession on this isolated volcanic island. However, the study also found that soil nematode communities may show a different pattern of succession than plant communities.
{"title":"Soil nematode communities on Surtsey, 50 years after the formation of the volcanic island","authors":"K. Ilieva-Makulec, B. Bjarnadóttir, B. Sigurdsson","doi":"10.16886/IAS.2015.05","DOIUrl":"https://doi.org/10.16886/IAS.2015.05","url":null,"abstract":"Soil nematodes are a key group that can both influence and reflect changes in the soil ecosystem. We investigated the generic composition, abundance and community structure of soil nematodes in two contrasting vegetation successional seres now found on the 50 year old volcanic island of Surtsey, Iceland. One represented the primary succession without much external input of nutrients (S1), while the other was a grassland that has evolved under a strong influence of allochthonous nutrient inputs by gulls (S2). In 2012 in total 25 genera of nematodes were identified, of which 14 were reported on Surtsey for the first time. Across the whole island, the nematode abundance and distribution was most strongly related to soil C:N ratio, soil acidity, plant cover and biomass. The nematode abundance was higher at S2 and there the trophic structure was dominated by bacterialand plantfeeders, while hyphal-feeders were more dominant at S1. Nematode communities have continued to change at S1 since the last nematode survey, which took place 17 years ago, even where the vegetation cover and composition has remained stable. This may indicate a gradual change in the soil environment at S1. Within S2, the nematode community had become denser and more structured, but still it had lower generic diversity than found at S1. Resource availability was found to be an important driver for nematode colonization and primary succession on this isolated volcanic island. However, the study also found that soil nematode communities may show a different pattern of succession than plant communities.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"28 1","pages":"43-58"},"PeriodicalIF":0.5,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The potential benefits of artificial inoculation with arbuscular mycorrhizal fungi (AMF) for lyme grass seedling establishment were tested in combination with varying fertilizer and seed rates in a long term revegetation study in two sandy deserts in Iceland. Fertilizer inputs proved more effective than other treatment variables in increasing vegetative growth, flowering and sand accretion of lyme grass seedlings. For this, re-fertilization was more important than the initial dose. AMF inoculation initially improved seedling growth but after the first year the effects became neutral or negative. While fertilization generally reduced AMF colonization, the negative effects of inoculation on lyme grass were enhanced by fertilization. Larger seed doses raised interand intraspecific competition, decreasing lyme grass vegetative regeneration and associate vegetation. Based on the current results, the application of AMF inoculation cannot be recommended for lyme grass establishment at the present. However, low seed rates (≤50 seeds m-2) and low initial fertilizer doses (≤10 g m-2) in combination with moderate re-fertilization application rates for a few years are apparently economical for the establishment of lyme grass for revegetation projects.
{"title":"Inoculation with arbuscular mycorrhizal fungi, fertilization and seed rates influence growth and development of lyme grass seedlings in two desert areas in Iceland","authors":"Ú. Óskarsson, W. Heyser","doi":"10.16886/IAS.2015.06","DOIUrl":"https://doi.org/10.16886/IAS.2015.06","url":null,"abstract":"The potential benefits of artificial inoculation with arbuscular mycorrhizal fungi (AMF) for lyme grass seedling establishment were tested in combination with varying fertilizer and seed rates in a long term revegetation study in two sandy deserts in Iceland. Fertilizer inputs proved more effective than other treatment variables in increasing vegetative growth, flowering and sand accretion of lyme grass seedlings. For this, re-fertilization was more important than the initial dose. AMF inoculation initially improved seedling growth but after the first year the effects became neutral or negative. While fertilization generally reduced AMF colonization, the negative effects of inoculation on lyme grass were enhanced by fertilization. Larger seed doses raised interand intraspecific competition, decreasing lyme grass vegetative regeneration and associate vegetation. Based on the current results, the application of AMF inoculation cannot be recommended for lyme grass establishment at the present. However, low seed rates (≤50 seeds m-2) and low initial fertilizer doses (≤10 g m-2) in combination with moderate re-fertilization application rates for a few years are apparently economical for the establishment of lyme grass for revegetation projects.","PeriodicalId":50396,"journal":{"name":"Icelandic Agricultural Sciences","volume":"47 1","pages":"59-80"},"PeriodicalIF":0.5,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67597541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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