The Experts below are selected from a list of 25164 Experts worldwide ranked by ideXlab platform
John L Harwood - One of the best experts on this subject based on the ideXlab platform.
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modification of Oil Crops to produce fatty acids for industrial applications
Fatty Acids#R##N#Chemistry Synthesis and Applications, 2017Co-Authors: John L Harwood, Helen Woodfield, Guanqun Chen, Randall J WeselakeAbstract:There are over a thousand naturally occurring fatty acids, many of which are present in plants. Broadly speaking, fewer than a dozen are quantitatively important but there is considerable potential to increase the usage of less common acids, especially as specialized chemicals or renewable feedstocks.
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informed metabolic engineering of Oil Crops using control analysis
Biocatalysis and agricultural biotechnology, 2014Co-Authors: Umi S Ramli, Patti A. Quant, Irina A. Guschina, Mingguo Tang, Tony Fawcett, John L HarwoodAbstract:Oil Crops are a very important agricultural commodity. Demand for such Oils is rising steadily (at more than 5% per year over the last half century). Although the majority of plant Oils are used for food or animal feed, there is increasing interest in their use as renewable chemicals for industry. Because of the demonstrated demand for Oils and finite agricultural land, attention is focussing on improving productivity. Genetic manipulation of crop plants needs a knowledge of the biosynthetic pathways concerned and how they are regulated. Although there are different ways to acquire much information, metabolic flux and metabolic control analyses are ways to provide quantitative assessments. In this review we describe our experiments using metabolic control analysis on important Crops – Oil palm, Oilseed rape, olive and soybean. Such research provides information for future informed genetic manipulations and we give a successful example of this in Oilseed rape (Brassica napus L.).
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regulation and enhancement of lipid accumulation in Oil Crops the use of metabolic control analysis for informed genetic manipulation
European Journal of Lipid Science and Technology, 2013Co-Authors: John L Harwood, Patti A. Quant, Umi S Ramli, Mingguo Tang, Tony Fawcett, Randall J Weselake, Irina A. GuschinaAbstract:Plant Oils are a very valuable agricultural commodity. They are currently mainly used (>80%) for food and animal feed but, increasingly, they have utility as renewable sources of industrial feedstocks or biofuel. Because of finite agricultural land, the best way to increase availability (in order to match demand) is by improving productivity. To do this requires a knowledge of metabolism and its regulation. Various methods have been used to provide information but only systems biology can yield quantitative data about complete metabolic pathways. We have used metabolic control analysis to provide information about major Oil Crops such as Oilseed rape, Oil palm, olive, and soybean. Such knowledge has then been used to inform genetic manipulation for crop improvement.
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Regulation of lipid synthesis in Oil Crops
FEBS letters, 2013Co-Authors: John L Harwood, Irina A. GuschinaAbstract:Oil Crops are in increasing demand both for food and as renewable sources of chemicals. It is therefore vital to understand how Oil accumulation is regulated. Different ways of obtaining such information are discussed with an emphasis on metabolic control analysis. The usefulness of the latter has been well-illustrated by its application to help raise yields in Oilseed rape.
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Control analysis of lipid biosynthesis in tissue cultures from Oil Crops shows that flux control is shared between fatty acid synthesis and lipid assembly
Biochemical Journal, 2002Co-Authors: Umi S Ramli, Darren S. Baker, Patti A. Quant, John L HarwoodAbstract:Top-Down (Metabolic) Control Analysis (TDCA) was used to examine, quantitatively, lipid biosynthesis in tissue cultures from two commercially important Oil Crops, olive (Olea europaea L.) and Oil palm (Elaeis guineensis Jacq.). A conceptually simplified system was defined comprising two blocks of reactions: fatty acid synthesis (Block A) and lipid assembly (Block B), which produced and consumed, respectively, a common and unique system intermediate, cytosolic acyl-CoA. We manipulated the steady-state levels of the system intermediate by adding exogenous oleic acid and, using two independent assays, measured the effect of the addition on the system fluxes (JA and JB). These were the rate of incorporation of radioactivity: (i) through Block A from [1-14C]acetate into fatty acids and (ii) via Block B from [U-14C]glycerol into complex lipids respectively. The data showed that fatty acid formation (Block A) exerted higher control than lipid assembly (Block B) in both tissues with the following group flux control coefficients (C):(i) Oil palm: *CJTL/BikA=0.64
Denis J. Murphy - One of the best experts on this subject based on the ideXlab platform.
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using modern plant breeding to improve the nutritional and technological qualities of Oil Crops
OCL, 2014Co-Authors: Denis J. MurphyAbstract:The last few decades have seen huge advances in our understanding of plant biology and in the development of new technologies for the manipulation of crop plants. The application of relatively straightforward breeding and selection methods made possible the “Green Revolution” of the 1960s and 1970s that effectively doubled or trebled cereal production in much of the world and averted mass famine in Asia. During the 2000s, much attention has been focused on genomic approaches to plant breeding with the deployment of a new generation of technologies, such as marker-assisted selection, next-generation sequencing, transgenesis (genetic engineering or GM) and automatic mutagenesis/selection (TILLING, TargetIng Local Lesions IN Genomes). These methods are now being applied to a wide range of Crops and have particularly good potential for Oil crop improvement in terms of both overall food and non-food yield and nutritional and technical quality of the Oils. Key targets include increasing overall Oil yield and stability on a per seed or per fruit basis and very high oleic acid content in seed and fruit Oils for both premium edible and oleochemical applications. Other more specialised targets include Oils enriched in nutritionally desirable “fish Oil”-like fatty acids, especially very long chain !-3 acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), or increased levels of lipidic vitamins such as carotenoids, tocopherols and tocotrienes. Progress in producing such Oils in commercial Crops has been good in recent years with several varieties being released or at advanced stages of development.
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Oil Crops as Potential Sources of Biofuels
Technological Innovations in Major World Oil Crops Volume 2, 2011Co-Authors: Denis J. MurphyAbstract:For many thousands of years, Oil Crops have been used as sources of a wide range of edible and non-edible products, including fuels. However, during the twentieth century, their use as fuels became very limited as they were largely replaced by fossil fuels. This situation has changed dramatically over the past decade with mounting pressure to limit CO2 emissions from, and to reduce dependence on, fossil fuels. As a result, there has been a huge growth of interest in the use of plant-derived Oils as renewable alternative fuels such as biodiesel. At present, the major globally traded sources of biodiesel are mainstream commodity Oil Crops, principally Oil palm, soybean, and rapeseed. Other minor Oil Crops serve mainly as local sources of biodiesel. Although evidence can be conflicting, data from life-cycle analysis (LCA) studies tend to support biodiesel, especially tropical biodiesel Crops, as having more favourable net carbon/energy balances than most bioethanol Crops. Research is now focussing on ways to improve the balance sheet of biodiesel Crops even further by increasing their yield and manipulating fatty acid composition. New tropical biofuel Crops such as jatropha are also being developed and, while the yields of some current varieties have been disappointing, there are good prospects for further improvements over the next decade. In the longer term, the so-called “next generation” biofuel Crops such as Oil-producing or hydrogen-producing microalgae, or even non-carbon alternatives such as wind or solar power, may eventually largely replace conventional Oil Crops as sources of renewable fuel. This will enable Oil Crops to act as renewable sources of hydrocarbons, e.g. for manufacture of plastics, long after fossil sources are depleted.
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Biotechnology and the improvement of Oil Crops – genes, dreams and realities
Phytochemistry Reviews, 2002Co-Authors: Denis J. MurphyAbstract:During the past decade, there have been many optimistic claims concerning the potential of novel Oil-based products from genetically engineered Crops, particularly for the manufacture of a new generation of renewable, carbon-neutral, industrial materials. Such claims have been underpinned by an impressive series of scientific advances that have resulted in the isolation of genes encoding most of the enzymes directly involved in Oil biosynthesis. In some cases, these enzymes have even been re-engineered by site-directed or random mutagenesis to allow production of new fatty acid profiles that are not present in any existing organism. This has opened up the prospect of engineering `designer Oil Crops' to produce novel fatty acids with chain lengths from C8 to C24 and with a wide range of industrially useful functionalities, including hydroxylation, epoxidation, and conjugated and non-conjugated double or triple bonds. However, there remain significant technical challenges before this promise of designer transgenic Crops is likely to be translated into large-scale commercial reality. For example, it has proved surprisingly difficult to engineer high levels of novel fatty acids in genetically engineered transgenic plants, although many wild type seeds can readily accumulate 90–95% of a single fatty acid in their storage Oil. Another complication is the recent discovery of multiple pathways of triacylglycerol biosynthesis and the difficulty in ensuring that novel fatty acids are only channelled towards storage triacylglycerols and not to membrane or signalling lipids in major target Crops like rapeseed. New findings from our lab have suggested that there may also be problems with the tissue specificity of some of the `seed-specific' gene promoters that are commonly used in transgenic Crops. There are also considerable and often underestimated challenges associated with the economics, management and public acceptability of all transgenic Crops, even for non-food use. In most cases the projections of petroleum reserves over the next few decades make it unlikely that crop-derived commodity products that substitute for petroleum will be competitive. Also the scale of crop production required to generate millions of tonnes of commodity Oils, e.g., for biodegradable plastics, is likely to seriously impinge on food production at a time of increasing global populations, and is therefore unlikely to be acceptable. An alternative strategy to transgenic Oil Crops is to use molecular breeding techniques in order to develop new Crops that already synthesise high levels of novel fatty acids of interest. Finally, the most promising market sectors and product ranges for the future development of Oil crop biotechnology will be discussed.
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biotechnology and the improvement of Oil Crops genes dreams and realities
Phytochemistry Reviews, 2002Co-Authors: Denis J. MurphyAbstract:During the past decade, there have been many optimistic claims concerning the potential of novel Oil-based products from genetically engineered Crops, particularly for the manufacture of a new generation of renewable, carbon-neutral, industrial materials. Such claims have been underpinned by an impressive series of scientific advances that have resulted in the isolation of genes encoding most of the enzymes directly involved in Oil biosynthesis. In some cases, these enzymes have even been re-engineered by site-directed or random mutagenesis to allow production of new fatty acid profiles that are not present in any existing organism. This has opened up the prospect of engineering `designer Oil Crops' to produce novel fatty acids with chain lengths from C8 to C24 and with a wide range of industrially useful functionalities, including hydroxylation, epoxidation, and conjugated and non-conjugated double or triple bonds. However, there remain significant technical challenges before this promise of designer transgenic Crops is likely to be translated into large-scale commercial reality. For example, it has proved surprisingly difficult to engineer high levels of novel fatty acids in genetically engineered transgenic plants, although many wild type seeds can readily accumulate 90–95% of a single fatty acid in their storage Oil. Another complication is the recent discovery of multiple pathways of triacylglycerol biosynthesis and the difficulty in ensuring that novel fatty acids are only channelled towards storage triacylglycerols and not to membrane or signalling lipids in major target Crops like rapeseed. New findings from our lab have suggested that there may also be problems with the tissue specificity of some of the `seed-specific' gene promoters that are commonly used in transgenic Crops. There are also considerable and often underestimated challenges associated with the economics, management and public acceptability of all transgenic Crops, even for non-food use. In most cases the projections of petroleum reserves over the next few decades make it unlikely that crop-derived commodity products that substitute for petroleum will be competitive. Also the scale of crop production required to generate millions of tonnes of commodity Oils, e.g., for biodegradable plastics, is likely to seriously impinge on food production at a time of increasing global populations, and is therefore unlikely to be acceptable. An alternative strategy to transgenic Oil Crops is to use molecular breeding techniques in order to develop new Crops that already synthesise high levels of novel fatty acids of interest. Finally, the most promising market sectors and product ranges for the future development of Oil crop biotechnology will be discussed.
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PRODUCTION OF NOVEL OilS IN PLANTS
Current opinion in biotechnology, 1999Co-Authors: Denis J. MurphyAbstract:Abstract We have now isolated the great majority of genes encoding enzymes of storage Oil biosynthesis in plants. In the past two years, particular progress has been made with acyltransferases, ketoacyl-acyl carrier protein synthetases and with desaturases and their relatives. In some cases, these enzymes have been re-engineered to create novel products. Nevertheless, the single or multiple insertion of such transgenes into Oil Crops has not always led to the desired phenotype. We are only now beginning to appreciate some of the complexities of storage and membrane lipid formation, such as acyl group remodelling and the turnover of unusual fatty acids. This understanding will be vital for future attempts at the rational engineering of transgenic Oil Crops. In parallel with this, the domestication of plants already synthesising useful fatty acids should be considered as a real alternative to the transgenic approach to producing novel Oil Crops.
Ulrich Köpke - One of the best experts on this subject based on the ideXlab platform.
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faba bean vicia faba l intercropped with Oil Crops a strategy to enhance rooting density and to optimize nitrogen use and grain production
Field Crops Research, 2012Co-Authors: Daniela Schröder, Ulrich KöpkeAbstract:Abstract Intercropping of faba bean (FB) and Oil Crops (OC) has two main features: competition in the areal parts and competition as well as facilitation in the underground parts. Root distribution, nitrogen use, and grain yields of faba bean ( Vicia faba L.) intercropped with safflower ( Carthamus tinctorius L.) (SAF) or white mustard ( Sinapis alba L.) (MUS), were investigated in field experiments at two sites in the Rhineland region of Germany. The crop species were grown both as sole Crops and as interCrops with reduced sowing densities. In intercropped FB, row spacing was 56 cm with two OC rows in between. This study aimed at optimizing the rooting pattern and therefore enhancing sOil space use, nitrogen acquisition, and grain production. Intercropping resulted in a more regular horizontal root distribution compared with sole cropped FB. In comparison to sole cropped FB, intercropping with SAF and MUS enhanced the root-length density in the subsOil, whereas the amount of plant-available sOil nitrogen was reduced at all sampling dates. Compared with sole-cropped FB, nitrogen accumulation in FB intercrop shoots was reduced because of reduced sowing density of FB. Total nitrogen accumulation in shoots was ranked as follows: sole-cropped FB > FB interCrops > sole-cropped OC. Regarding the individual FB plant, in interCrops nitrogen acquisition was enhanced at floodplain site ‘Wiesengut’ where the competiveness of OC was rather low. Compared with sole cropping land equivalent ratios for grain yield dry matter of interCrops were increased at the site ‘Klein-Altendorf’ but not at ‘Wiesengut’. However, land equivalent ratios for total nitrogen accumulation (LER-N) in FB intercropped treatments were generally enhanced by 12% (SAF) to 18% (MUS) when compared with sole cropping. Thus, intercropping greatly influenced yield performance, depending on site specific competition: at the floodplain site ‘Wiesengut’ OC grain yields were significantly reduced by shoot competition, whereas on the more fertile loessial sOil at the site ‘Klein-Altendorf’ that released higher amounts of sOil nitrogen, FB grain yields were significantly reduced by high Oil crop competiveness. Consequently, the advantages (reduced plant-available sOil nitrogen) and disadvantages (reduced FB grain yield) of growing FB intercropped with OC have to be weighed according to site conditions and the decision regarding which is the most valuable cash crop.
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Faba bean (Vicia faba L.) intercropped with Oil Crops – a strategy to enhance rooting density and to optimize nitrogen use and grain production?
Field Crops Research, 2012Co-Authors: Daniela Schröder, Ulrich KöpkeAbstract:Abstract Intercropping of faba bean (FB) and Oil Crops (OC) has two main features: competition in the areal parts and competition as well as facilitation in the underground parts. Root distribution, nitrogen use, and grain yields of faba bean ( Vicia faba L.) intercropped with safflower ( Carthamus tinctorius L.) (SAF) or white mustard ( Sinapis alba L.) (MUS), were investigated in field experiments at two sites in the Rhineland region of Germany. The crop species were grown both as sole Crops and as interCrops with reduced sowing densities. In intercropped FB, row spacing was 56 cm with two OC rows in between. This study aimed at optimizing the rooting pattern and therefore enhancing sOil space use, nitrogen acquisition, and grain production. Intercropping resulted in a more regular horizontal root distribution compared with sole cropped FB. In comparison to sole cropped FB, intercropping with SAF and MUS enhanced the root-length density in the subsOil, whereas the amount of plant-available sOil nitrogen was reduced at all sampling dates. Compared with sole-cropped FB, nitrogen accumulation in FB intercrop shoots was reduced because of reduced sowing density of FB. Total nitrogen accumulation in shoots was ranked as follows: sole-cropped FB > FB interCrops > sole-cropped OC. Regarding the individual FB plant, in interCrops nitrogen acquisition was enhanced at floodplain site ‘Wiesengut’ where the competiveness of OC was rather low. Compared with sole cropping land equivalent ratios for grain yield dry matter of interCrops were increased at the site ‘Klein-Altendorf’ but not at ‘Wiesengut’. However, land equivalent ratios for total nitrogen accumulation (LER-N) in FB intercropped treatments were generally enhanced by 12% (SAF) to 18% (MUS) when compared with sole cropping. Thus, intercropping greatly influenced yield performance, depending on site specific competition: at the floodplain site ‘Wiesengut’ OC grain yields were significantly reduced by shoot competition, whereas on the more fertile loessial sOil at the site ‘Klein-Altendorf’ that released higher amounts of sOil nitrogen, FB grain yields were significantly reduced by high Oil crop competiveness. Consequently, the advantages (reduced plant-available sOil nitrogen) and disadvantages (reduced FB grain yield) of growing FB intercropped with OC have to be weighed according to site conditions and the decision regarding which is the most valuable cash crop.
Patti A. Quant - One of the best experts on this subject based on the ideXlab platform.
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informed metabolic engineering of Oil Crops using control analysis
Biocatalysis and agricultural biotechnology, 2014Co-Authors: Umi S Ramli, Patti A. Quant, Irina A. Guschina, Mingguo Tang, Tony Fawcett, John L HarwoodAbstract:Oil Crops are a very important agricultural commodity. Demand for such Oils is rising steadily (at more than 5% per year over the last half century). Although the majority of plant Oils are used for food or animal feed, there is increasing interest in their use as renewable chemicals for industry. Because of the demonstrated demand for Oils and finite agricultural land, attention is focussing on improving productivity. Genetic manipulation of crop plants needs a knowledge of the biosynthetic pathways concerned and how they are regulated. Although there are different ways to acquire much information, metabolic flux and metabolic control analyses are ways to provide quantitative assessments. In this review we describe our experiments using metabolic control analysis on important Crops – Oil palm, Oilseed rape, olive and soybean. Such research provides information for future informed genetic manipulations and we give a successful example of this in Oilseed rape (Brassica napus L.).
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regulation and enhancement of lipid accumulation in Oil Crops the use of metabolic control analysis for informed genetic manipulation
European Journal of Lipid Science and Technology, 2013Co-Authors: John L Harwood, Patti A. Quant, Umi S Ramli, Mingguo Tang, Tony Fawcett, Randall J Weselake, Irina A. GuschinaAbstract:Plant Oils are a very valuable agricultural commodity. They are currently mainly used (>80%) for food and animal feed but, increasingly, they have utility as renewable sources of industrial feedstocks or biofuel. Because of finite agricultural land, the best way to increase availability (in order to match demand) is by improving productivity. To do this requires a knowledge of metabolism and its regulation. Various methods have been used to provide information but only systems biology can yield quantitative data about complete metabolic pathways. We have used metabolic control analysis to provide information about major Oil Crops such as Oilseed rape, Oil palm, olive, and soybean. Such knowledge has then been used to inform genetic manipulation for crop improvement.
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Control analysis of lipid biosynthesis in tissue cultures from Oil Crops shows that flux control is shared between fatty acid synthesis and lipid assembly
Biochemical Journal, 2002Co-Authors: Umi S Ramli, Darren S. Baker, Patti A. Quant, John L HarwoodAbstract:Top-Down (Metabolic) Control Analysis (TDCA) was used to examine, quantitatively, lipid biosynthesis in tissue cultures from two commercially important Oil Crops, olive (Olea europaea L.) and Oil palm (Elaeis guineensis Jacq.). A conceptually simplified system was defined comprising two blocks of reactions: fatty acid synthesis (Block A) and lipid assembly (Block B), which produced and consumed, respectively, a common and unique system intermediate, cytosolic acyl-CoA. We manipulated the steady-state levels of the system intermediate by adding exogenous oleic acid and, using two independent assays, measured the effect of the addition on the system fluxes (JA and JB). These were the rate of incorporation of radioactivity: (i) through Block A from [1-14C]acetate into fatty acids and (ii) via Block B from [U-14C]glycerol into complex lipids respectively. The data showed that fatty acid formation (Block A) exerted higher control than lipid assembly (Block B) in both tissues with the following group flux control coefficients (C):(i) Oil palm: *CJTL/BikA=0.64
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Control analysis of lipid biosynthesis in tissue cultures from Oil Crops shows that flux control is shared between fatty acid synthesis and lipid assembly
Biochemical Journal, 2002Co-Authors: Umi Salamah Ramli, Darren S. Baker, Patti A. Quant, John L HarwoodAbstract:Top-Down (Metabolic) Control Analysis (TDCA) was used to examine, quantitatively, lipid biosynthesis in tissue cultures from two commercially important Oil Crops, olive (Olea europaea L.) and Oil palm (Elaeis guineensis Jacq.). A conceptually simplified system was defined comprising two blocks of reactions: fatty acid synthesis (Block A) and lipid assembly (Block B), which produced and consumed, respectively, a common and unique system intermediate, cytosolic acyl-CoA. We manipulated the steady-state levels of the system intermediate by adding exogenous oleic acid and, using two independent assays, measured the effect of the addition on the system fluxes (J(A) and J(B)). These were the rate of incorporation of radioactivity: (i) through Block A from [1-(14)C]acetate into fatty acids and (ii) via Block B from [U-(14)C]glycerol into complex lipids respectively. The data showed that fatty acid formation (Block A) exerted higher control than lipid assembly (Block B) in both tissues with the following group flux control coefficients (C):(i) Oil palm: *C(J(TL))(BlkA)=0.64+/-0.05 and *C(J(TL))(BlkB)=0.36+/-0.05(ii) Olive: *C(J(TL))(BlkA)=0.57+/-0.10 and *C(J(TL))(BlkB)=0.43+/-0.10where *C indicates the group flux control coefficient over the lipid biosynthesis flux (J(TL)) and the subscripts BlkA and BlkB refer to defined blocks of the system, Block A and Block B. Nevertheless, because both parts of the lipid biosynthetic pathway exert significant flux control, we suggest strongly that manipulation of single enzyme steps will not affect product yield appreciably. The present study represents the first use of TDCA to examine the overall lipid biosynthetic pathway in any tissue, and its findings are of immediate academic and economic relevance to the yield and nutritional quality of Oil Crops.
Daniela Schröder - One of the best experts on this subject based on the ideXlab platform.
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faba bean vicia faba l intercropped with Oil Crops a strategy to enhance rooting density and to optimize nitrogen use and grain production
Field Crops Research, 2012Co-Authors: Daniela Schröder, Ulrich KöpkeAbstract:Abstract Intercropping of faba bean (FB) and Oil Crops (OC) has two main features: competition in the areal parts and competition as well as facilitation in the underground parts. Root distribution, nitrogen use, and grain yields of faba bean ( Vicia faba L.) intercropped with safflower ( Carthamus tinctorius L.) (SAF) or white mustard ( Sinapis alba L.) (MUS), were investigated in field experiments at two sites in the Rhineland region of Germany. The crop species were grown both as sole Crops and as interCrops with reduced sowing densities. In intercropped FB, row spacing was 56 cm with two OC rows in between. This study aimed at optimizing the rooting pattern and therefore enhancing sOil space use, nitrogen acquisition, and grain production. Intercropping resulted in a more regular horizontal root distribution compared with sole cropped FB. In comparison to sole cropped FB, intercropping with SAF and MUS enhanced the root-length density in the subsOil, whereas the amount of plant-available sOil nitrogen was reduced at all sampling dates. Compared with sole-cropped FB, nitrogen accumulation in FB intercrop shoots was reduced because of reduced sowing density of FB. Total nitrogen accumulation in shoots was ranked as follows: sole-cropped FB > FB interCrops > sole-cropped OC. Regarding the individual FB plant, in interCrops nitrogen acquisition was enhanced at floodplain site ‘Wiesengut’ where the competiveness of OC was rather low. Compared with sole cropping land equivalent ratios for grain yield dry matter of interCrops were increased at the site ‘Klein-Altendorf’ but not at ‘Wiesengut’. However, land equivalent ratios for total nitrogen accumulation (LER-N) in FB intercropped treatments were generally enhanced by 12% (SAF) to 18% (MUS) when compared with sole cropping. Thus, intercropping greatly influenced yield performance, depending on site specific competition: at the floodplain site ‘Wiesengut’ OC grain yields were significantly reduced by shoot competition, whereas on the more fertile loessial sOil at the site ‘Klein-Altendorf’ that released higher amounts of sOil nitrogen, FB grain yields were significantly reduced by high Oil crop competiveness. Consequently, the advantages (reduced plant-available sOil nitrogen) and disadvantages (reduced FB grain yield) of growing FB intercropped with OC have to be weighed according to site conditions and the decision regarding which is the most valuable cash crop.
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Faba bean (Vicia faba L.) intercropped with Oil Crops – a strategy to enhance rooting density and to optimize nitrogen use and grain production?
Field Crops Research, 2012Co-Authors: Daniela Schröder, Ulrich KöpkeAbstract:Abstract Intercropping of faba bean (FB) and Oil Crops (OC) has two main features: competition in the areal parts and competition as well as facilitation in the underground parts. Root distribution, nitrogen use, and grain yields of faba bean ( Vicia faba L.) intercropped with safflower ( Carthamus tinctorius L.) (SAF) or white mustard ( Sinapis alba L.) (MUS), were investigated in field experiments at two sites in the Rhineland region of Germany. The crop species were grown both as sole Crops and as interCrops with reduced sowing densities. In intercropped FB, row spacing was 56 cm with two OC rows in between. This study aimed at optimizing the rooting pattern and therefore enhancing sOil space use, nitrogen acquisition, and grain production. Intercropping resulted in a more regular horizontal root distribution compared with sole cropped FB. In comparison to sole cropped FB, intercropping with SAF and MUS enhanced the root-length density in the subsOil, whereas the amount of plant-available sOil nitrogen was reduced at all sampling dates. Compared with sole-cropped FB, nitrogen accumulation in FB intercrop shoots was reduced because of reduced sowing density of FB. Total nitrogen accumulation in shoots was ranked as follows: sole-cropped FB > FB interCrops > sole-cropped OC. Regarding the individual FB plant, in interCrops nitrogen acquisition was enhanced at floodplain site ‘Wiesengut’ where the competiveness of OC was rather low. Compared with sole cropping land equivalent ratios for grain yield dry matter of interCrops were increased at the site ‘Klein-Altendorf’ but not at ‘Wiesengut’. However, land equivalent ratios for total nitrogen accumulation (LER-N) in FB intercropped treatments were generally enhanced by 12% (SAF) to 18% (MUS) when compared with sole cropping. Thus, intercropping greatly influenced yield performance, depending on site specific competition: at the floodplain site ‘Wiesengut’ OC grain yields were significantly reduced by shoot competition, whereas on the more fertile loessial sOil at the site ‘Klein-Altendorf’ that released higher amounts of sOil nitrogen, FB grain yields were significantly reduced by high Oil crop competiveness. Consequently, the advantages (reduced plant-available sOil nitrogen) and disadvantages (reduced FB grain yield) of growing FB intercropped with OC have to be weighed according to site conditions and the decision regarding which is the most valuable cash crop.
