Pub Date : 2003-01-01DOI: 10.1080/09064710310003925
H. Kirchmann, L. Bergström
The term paper-mill waste is used for different products: de-inked fiber sludge, primary fiber sludge, secondary sludge and mixtures. The aim of this study was to find out if any of these materials can be safely used on agricultural soils to induce net N immobilization of N, and thereby decrease nitrate (NO 3 ) leaching. Chemical characterization showed that secondary sludge derived from biological waste water treatment was a nutrient-rich material low in fiber content, whereas primary and de-inked fiber sludge were high in fiber content and low in nutrient content. Cellulose-C and hemi-cellulose-C amounted to 46% and 36% of the organic C present, respectively, and C/N ratios were around 130 in primary and de-inked fiber sludge. Incubation studies at 8°C over 2 months showed that the decomposability of primary and de-inked fiber sludge in soil was not significantly different. Both showed lower decomposability than secondary sludge. Concentrations of inorganic N in soil declined to very low levels after application of primary and deinked fiber sludge and their capacity for net N immobilization was 4.8-7.2 kg N t - 1 C added at 5°C. However, contents of Cu, Cd and polycyclic aromatic hydrocarbons in de-inked fiber sludge limit its use on arable land. Only primary fiber sludge was found to be suitable as a introgen catch fiber material for use on agricultural soils.
造纸厂废物一词用于不同的产品:脱墨纤维污泥、原纤维污泥、二次污泥和混合物。本研究的目的是找出是否有任何这些材料可以安全地用于农业土壤，以诱导N的净氮固定，从而减少硝态氮(no3)的淋失。化学表征表明，生物废水处理产生的二次污泥是一种营养丰富、纤维含量低的物质，而原浆和脱墨纤维污泥则是纤维含量高、营养含量低的物质。纤维素-C和半纤维素-C分别占有机碳的46%和36%，原生和脱墨纤维污泥的碳氮比约为130。在8°C条件下2个月的培养研究表明，原生纤维污泥和脱墨纤维污泥在土壤中的分解能力没有显著差异。两者的分解能力均低于二次污泥。施用原生纤维污泥和脱墨纤维污泥后，土壤中无机氮的浓度下降到非常低的水平，在5°C下，它们的净氮固定能力为4.8-7.2 kg N / t - 1 C。但脱墨纤维污泥中Cu、Cd和多环芳烃的含量限制了其在耕地上的利用。发现只有原纤维污泥适合作为农业土壤的氮素捕获纤维材料。
{"title":"Use of Paper-mill Wastes on Agricultural Soils: Is This a Way to Reduce Nitrate Leaching?","authors":"H. Kirchmann, L. Bergström","doi":"10.1080/09064710310003925","DOIUrl":"https://doi.org/10.1080/09064710310003925","url":null,"abstract":"The term paper-mill waste is used for different products: de-inked fiber sludge, primary fiber sludge, secondary sludge and mixtures. The aim of this study was to find out if any of these materials can be safely used on agricultural soils to induce net N immobilization of N, and thereby decrease nitrate (NO 3 ) leaching. Chemical characterization showed that secondary sludge derived from biological waste water treatment was a nutrient-rich material low in fiber content, whereas primary and de-inked fiber sludge were high in fiber content and low in nutrient content. Cellulose-C and hemi-cellulose-C amounted to 46% and 36% of the organic C present, respectively, and C/N ratios were around 130 in primary and de-inked fiber sludge. Incubation studies at 8°C over 2 months showed that the decomposability of primary and de-inked fiber sludge in soil was not significantly different. Both showed lower decomposability than secondary sludge. Concentrations of inorganic N in soil declined to very low levels after application of primary and deinked fiber sludge and their capacity for net N immobilization was 4.8-7.2 kg N t - 1 C added at 5°C. However, contents of Cu, Cd and polycyclic aromatic hydrocarbons in de-inked fiber sludge limit its use on arable land. Only primary fiber sludge was found to be suitable as a introgen catch fiber material for use on agricultural soils.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85778222","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}
Pub Date : 2003-01-01DOI: 10.1080/0906471030005518
M. Wivstad, B. Båth
A study carried out in Uppsala, Sweden, compared three legumes: red clover (Trifolium pratense), lucerne (Medicago sativa) and yellow sweet clover (Melilotus officinalis) as a green manure for an early and late crop of Iceberg lettuce (Lactuca sativa crispa). Differences between the treatments were only apparent in the early crop of lettuce. With the early crop, the dry matter content of the leguminous green manure was more significant in effect on yield than its nutrient content. Red clover and lucerne provided approximately the same level of nutrients as yellow sweet clover, but despite this gave lower yields of Iceberg lettuce than the yellow sweet clover. A possible reason for this was that the higher amount of dry matter supplied by the yellow sweet clover had a positive effect on soil structure and thus improved lettuce rooting and water uptake. The results indicate that at farm level, reliability of biomass production is more important in choice of a green manure crop than chemical and morphological properties of the species.
{"title":"Legumes as a nutrient source for Iceberg lettuce (Lactuca sativa crispa)","authors":"M. Wivstad, B. Båth","doi":"10.1080/0906471030005518","DOIUrl":"https://doi.org/10.1080/0906471030005518","url":null,"abstract":"A study carried out in Uppsala, Sweden, compared three legumes: red clover (Trifolium pratense), lucerne (Medicago sativa) and yellow sweet clover (Melilotus officinalis) as a green manure for an early and late crop of Iceberg lettuce (Lactuca sativa crispa). Differences between the treatments were only apparent in the early crop of lettuce. With the early crop, the dry matter content of the leguminous green manure was more significant in effect on yield than its nutrient content. Red clover and lucerne provided approximately the same level of nutrients as yellow sweet clover, but despite this gave lower yields of Iceberg lettuce than the yellow sweet clover. A possible reason for this was that the higher amount of dry matter supplied by the yellow sweet clover had a positive effect on soil structure and thus improved lettuce rooting and water uptake. The results indicate that at farm level, reliability of biomass production is more important in choice of a green manure crop than chemical and morphological properties of the species.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72413220","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}
Pub Date : 2003-01-01DOI: 10.1080/09064710310006490
B. Lundegårdh, A. Mårtensson
If in plant secondary metabolites, the presence of pesticides and nutritional balances are the most important determinants of nutritional value of food plants, then organically produced plant foods could be expected to bemore health-promoting than conventional foods. Differences arise in management practices between organic and conventional farming where the former support (a) an activation of the plant defence mechanisms by excluding synthetic plant protection agents, (b) an active soil life where plants and microbes interact, exchanging certain metabolic compounds and (c) a balanced mineral nutrient uptake where excesses of easily available nutrients are avoided.
{"title":"Organically produced plant foods: Evidence of health benefits","authors":"B. Lundegårdh, A. Mårtensson","doi":"10.1080/09064710310006490","DOIUrl":"https://doi.org/10.1080/09064710310006490","url":null,"abstract":"If in plant secondary metabolites, the presence of pesticides and nutritional balances are the most important determinants of nutritional value of food plants, then organically produced plant foods could be expected to bemore health-promoting than conventional foods. Differences arise in management practices between organic and conventional farming where the former support (a) an activation of the plant defence mechanisms by excluding synthetic plant protection agents, (b) an active soil life where plants and microbes interact, exchanging certain metabolic compounds and (c) a balanced mineral nutrient uptake where excesses of easily available nutrients are avoided.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73176005","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}
Pub Date : 2003-01-01DOI: 10.1080/09064710310006508
B. Nordskog, A. Stensvand, N. Heiberg
Cultivated blackberry (Rubus fruticosus) was recently introduced in Norway, and most plantings were established in the 1990's. Many of these plantings died back or had severe damage on leaves and stems. Plant pathogens incombination with frost injury were suspected to be the cause of the damage. In 1998-99, field and greenhouse plantings of blackberry were surveyed for the occurrence of plant pathogenic and saprophytic fungi. A total of 33 different fungi were identified in 18 cultivars from 23 plantings (19 field and 4 greenhouse). Of these, 12 were pathogenic fungi, while 21 were non-pathogenic, secondary invaders. The most important pathogens on the canes were (common name in parenthesis) Septocyta ruborum (Purple blotch), Gnomonia rubi (Gnomonia canker) and Sydowiella depressula (Sydowiella canker). Pathogenic fungi of less importance on the canes were Elsinoe veneta (Anthracnose) and Coniothyrium fuckelii (Cane blight). Peronospora sparsa (Downy mildew) was the most important fungus attacking leaves. On fruits Botrytis cinerea (Grey mould) was the most prevalent pathogen. Cladosporium spp. (Cladosporium rot) and Penicillium spp. (Blue mould) were frequently observed on fruits, but did not seem to be of significant importance. Other minor fruit rots were due to Colletotrichum gloeosporioides (Bitter rot) and Mucor sp. (Mucor rot). Phragmidium violaceum (Blackberry rust) was found on canes and leaves, but was of minor importance. G. rubi and S. depressula caused damage mostly in the thornless cultivars, and P. sparsa was found almost exclusively in the thornless cultivar 'Loch Ness'. Both thorny and thornless cultivars were damaged by S. ruborum. In greenhouses the major fungal problem was B. cinerea.
{"title":"Fungi occurring on aerial constituents of cultivated blackberry (Rubus fruticosus L.) in Norway.","authors":"B. Nordskog, A. Stensvand, N. Heiberg","doi":"10.1080/09064710310006508","DOIUrl":"https://doi.org/10.1080/09064710310006508","url":null,"abstract":"Cultivated blackberry (Rubus fruticosus) was recently introduced in Norway, and most plantings were established in the 1990's. Many of these plantings died back or had severe damage on leaves and stems. Plant pathogens incombination with frost injury were suspected to be the cause of the damage. In 1998-99, field and greenhouse plantings of blackberry were surveyed for the occurrence of plant pathogenic and saprophytic fungi. A total of 33 different fungi were identified in 18 cultivars from 23 plantings (19 field and 4 greenhouse). Of these, 12 were pathogenic fungi, while 21 were non-pathogenic, secondary invaders. The most important pathogens on the canes were (common name in parenthesis) Septocyta ruborum (Purple blotch), Gnomonia rubi (Gnomonia canker) and Sydowiella depressula (Sydowiella canker). Pathogenic fungi of less importance on the canes were Elsinoe veneta (Anthracnose) and Coniothyrium fuckelii (Cane blight). Peronospora sparsa (Downy mildew) was the most important fungus attacking leaves. On fruits Botrytis cinerea (Grey mould) was the most prevalent pathogen. Cladosporium spp. (Cladosporium rot) and Penicillium spp. (Blue mould) were frequently observed on fruits, but did not seem to be of significant importance. Other minor fruit rots were due to Colletotrichum gloeosporioides (Bitter rot) and Mucor sp. (Mucor rot). Phragmidium violaceum (Blackberry rust) was found on canes and leaves, but was of minor importance. G. rubi and S. depressula caused damage mostly in the thornless cultivars, and P. sparsa was found almost exclusively in the thornless cultivar 'Loch Ness'. Both thorny and thornless cultivars were damaged by S. ruborum. In greenhouses the major fungal problem was B. cinerea.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79249758","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}
Pub Date : 2003-01-01DOI: 10.1080/09064710310005545
J. Lipa, B. Ekbom
{"title":"Parasites of Phyllotreta undulata L. (Coleoptera, Chrysomelidae) in Sweden","authors":"J. Lipa, B. Ekbom","doi":"10.1080/09064710310005545","DOIUrl":"https://doi.org/10.1080/09064710310005545","url":null,"abstract":"","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81846283","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}
Pub Date : 1999-12-12DOI: 10.1080/090647100750001550
A. Dexter, J. Arvidsson, E. Czyż, A. Trautner, B. Stenberg
{"title":"Respiration rates of soil aggregates in relation to tillage and straw-management practices in the field.","authors":"A. Dexter, J. Arvidsson, E. Czyż, A. Trautner, B. Stenberg","doi":"10.1080/090647100750001550","DOIUrl":"https://doi.org/10.1080/090647100750001550","url":null,"abstract":"","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"1999-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89622010","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 applicability of an expolinear growth equation for describing dry matter yield was investigated in seven field experiments for spring growth of timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) under two levels of N application. The equation was expanded by a growth index (GI) correcting for variations in radiation, temperature and plant-available soil moisture, and an ageing function describing the decrease in growth rate caused by advance in phenological development. The field sites covered a wide range of climatic conditions and the yield was recorded at five phenological stages from leaf stage to anthesis. The expansion of the equation appeared to be adequate for a combined analysis of the dry matter yield in meadow fescue and timothy. The estimated maximum growth rate during the linear phase (C m) did not differ significantly between species. C m increased with higher N application. It was concluded that C m of the expanded model represented a potential rate, whereas the re...
{"title":"Modelling Spring Growth of Timothy and Meadow Fescue by an Expolinear Growth Equation","authors":"H. Bonesmo","doi":"10.1080/713782022","DOIUrl":"https://doi.org/10.1080/713782022","url":null,"abstract":"The applicability of an expolinear growth equation for describing dry matter yield was investigated in seven field experiments for spring growth of timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) under two levels of N application. The equation was expanded by a growth index (GI) correcting for variations in radiation, temperature and plant-available soil moisture, and an ageing function describing the decrease in growth rate caused by advance in phenological development. The field sites covered a wide range of climatic conditions and the yield was recorded at five phenological stages from leaf stage to anthesis. The expansion of the equation appeared to be adequate for a combined analysis of the dry matter yield in meadow fescue and timothy. The estimated maximum growth rate during the linear phase (C m) did not differ significantly between species. C m increased with higher N application. It was concluded that C m of the expanded model represented a potential rate, whereas the re...","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87767668","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}
A. Hermansen, T. Amundsen, G. Taksdal, S. Dragland, G. Synnevåg, M. Flønes, L. Sundheim
Infection by Mycocentrospora acerina in carrots was examined in the period 1985-1995 in monoculture plots at four sites with crop-rotation experiments in Norway. At two of the locations, with the most variable climate, the incidence and severity of M. acerina infections on leaves and roots varied most through the different years. At these locations M. acerina attack on the roots was positively correlated with precipitation in July. At one location the incidence of leaf infection corresponded significantly with the incidence on the roots. At one site the length of the storage period correlated with the incidence and severity of liquorice rot in storage.
{"title":"Variations in Infection by Mycocentrospora acerina in Carrot Monoculture Plots at Four Sites during 1985-1995","authors":"A. Hermansen, T. Amundsen, G. Taksdal, S. Dragland, G. Synnevåg, M. Flønes, L. Sundheim","doi":"10.1080/713782023","DOIUrl":"https://doi.org/10.1080/713782023","url":null,"abstract":"Infection by Mycocentrospora acerina in carrots was examined in the period 1985-1995 in monoculture plots at four sites with crop-rotation experiments in Norway. At two of the locations, with the most variable climate, the incidence and severity of M. acerina infections on leaves and roots varied most through the different years. At these locations M. acerina attack on the roots was positively correlated with precipitation in July. At one location the incidence of leaf infection corresponded significantly with the incidence on the roots. At one site the length of the storage period correlated with the incidence and severity of liquorice rot in storage.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78466752","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}
Wheats grown in Sweden were investigated for the effects of genotype and environment on bread-making quality. Stability was also investigated. The results showed that both genotype and environment as well as their interaction had a significant influence on bread-making quality. Differences in stability were also found. In general, cultivars containing HMW glutenin subunits 5+10 had a higher gluten strength and also showed greater variation and less stability compared with those containing 2+12. When comparing bread-making quality over several years some promising cultivars were found. Drabant, Dragon, Dacke, Kosack and Stava were relatively good and stable among those cultivars containing HMW glutenin subunits 2+12. Avle and Tarso were the most promising of the cultivars with 5+10. The relatively weak character of Tarso despite the HMW glutenin subunits 5+10 might be due to the 1BL/1RS rye translocation in this cultivar.
{"title":"Genotype and Environment Effects on Bread-Making Quality of Swedish-Grown Wheat Cultivars Containing High-Molecular-Weight Glutenin Subunits 2+12 or 5+10","authors":"E. Johansson, G. Svensson, S. Tsegaye","doi":"10.1080/713782024","DOIUrl":"https://doi.org/10.1080/713782024","url":null,"abstract":"Wheats grown in Sweden were investigated for the effects of genotype and environment on bread-making quality. Stability was also investigated. The results showed that both genotype and environment as well as their interaction had a significant influence on bread-making quality. Differences in stability were also found. In general, cultivars containing HMW glutenin subunits 5+10 had a higher gluten strength and also showed greater variation and less stability compared with those containing 2+12. When comparing bread-making quality over several years some promising cultivars were found. Drabant, Dragon, Dacke, Kosack and Stava were relatively good and stable among those cultivars containing HMW glutenin subunits 2+12. Avle and Tarso were the most promising of the cultivars with 5+10. The relatively weak character of Tarso despite the HMW glutenin subunits 5+10 might be due to the 1BL/1RS rye translocation in this cultivar.","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81908220","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 relationship between phenological stage at the first cut and subsequent regrowth rates was studied in six field experiments with timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) under two levels of N application. The field sites were selected to cover a wide range of climatic conditions in Norway. Five weekly yield samplings during the regrowth periods were fitted to an expolinear growth equation to determine initial maximum relative regrowth rates (R m) and maximum regrowth rates (C m). The step from actual to potential rates was accomplished by weighting the obtained rates with a weather index. For both species R m was highest after an initial cut at the early vegetative stage. It was reduced by 50% at jointing, after which there was no change with later cuts. For both species the C m declined sharply with cutting time through the early stages of phenological development, whereas from early heading to anthesis there was no significant change. Compared with timothy, the C m va...
{"title":"Regrowth Rates of Timothy and Meadow Fescue Cut at Five Phenological Stages","authors":"H. Bonesmo, A. Skjelvåg","doi":"10.1080/713782028","DOIUrl":"https://doi.org/10.1080/713782028","url":null,"abstract":"The relationship between phenological stage at the first cut and subsequent regrowth rates was studied in six field experiments with timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.) under two levels of N application. The field sites were selected to cover a wide range of climatic conditions in Norway. Five weekly yield samplings during the regrowth periods were fitted to an expolinear growth equation to determine initial maximum relative regrowth rates (R m) and maximum regrowth rates (C m). The step from actual to potential rates was accomplished by weighting the obtained rates with a weather index. For both species R m was highest after an initial cut at the early vegetative stage. It was reduced by 50% at jointing, after which there was no change with later cuts. For both species the C m declined sharply with cutting time through the early stages of phenological development, whereas from early heading to anthesis there was no significant change. Compared with timothy, the C m va...","PeriodicalId":40817,"journal":{"name":"Acta Agriculturae Scandinavica Section B-Soil and Plant Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72970942","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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