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• 31. [Article] Chilling as a factor in crop location with particular reference to deciduous orchards in California

  Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing ...

  Citation × Citation Citation Abstract Copy Title: Chilling as a factor in crop location with particular reference to deciduous orchards in California Author: Aron, Robert Henry Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing only maximum and minimum temperatures had a coefficients of correlation (R) and R² values of .978 and .957, respectively. This equation was used in estimating the availability of chilling at 273 stations throughout California. Using these estimates and considering such factors as altitude and marine influences, the availability of chilling throughout California was mapped. Factors that influence the effectiveness of the chilling received such as low and high temperatures, high light intensity, shade, fog, cloud cover, topography and wind were analyzed. Which temperatures are most effective in satisfying the plant's chilling requirement, the amount required by different varieties, the effects and consequences of inadequate chilling, and treatments which may ameliorate the effects of inadequate chilling were considered. Hormonal and physical and anatomical plant response changes occurring during rest were discussed. Title: Chilling as a factor in crop location with particular reference to deciduous orchards in California Author: Aron, Robert Henry Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing only maximum and minimum temperatures had a coefficients of correlation (R) and R² values of .978 and .957, respectively. This equation was used in estimating the availability of chilling at 273 stations throughout California. Using these estimates and considering such factors as altitude and marine influences, the availability of chilling throughout California was mapped. Factors that influence the effectiveness of the chilling received such as low and high temperatures, high light intensity, shade, fog, cloud cover, topography and wind were analyzed. Which temperatures are most effective in satisfying the plant's chilling requirement, the amount required by different varieties, the effects and consequences of inadequate chilling, and treatments which may ameliorate the effects of inadequate chilling were considered. Hormonal and physical and anatomical plant response changes occurring during rest were discussed. Close

• 32. [Article] Foliar interception and uptake of ³⁶Cl by crops

  Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a ...

  Citation × Citation Citation Abstract Copy Title: Foliar interception and uptake of ³⁶Cl by crops Author: Bytwerk, David Paul Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a major pathway for the transport of radionuclides to human beings in scenarios relevant to the waste disposal community. Performance assessments of many repositories that predict doses to people from long- term geological disposal of radioactive waste are equipped to consider foliar interception and uptake by crops on an element and crop specific basis in their predictions, but crop and element specific data does not exist in the literature to justify the choice of parameter values in these models. ³⁶Cl is among the isotopes for which there is a lack of data and has recently been predicted to be among the largest contributors to dose at the time of peak dose from many repositories. Reported here are ³⁶Cl foliar interception, absorption, and translocation parameters for three crops: a root vegetable -radishes, a fruit - beans, and a grain - wheat. Title: Foliar interception and uptake of ³⁶Cl by crops Author: Bytwerk, David Paul Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a major pathway for the transport of radionuclides to human beings in scenarios relevant to the waste disposal community. Performance assessments of many repositories that predict doses to people from long- term geological disposal of radioactive waste are equipped to consider foliar interception and uptake by crops on an element and crop specific basis in their predictions, but crop and element specific data does not exist in the literature to justify the choice of parameter values in these models. ³⁶Cl is among the isotopes for which there is a lack of data and has recently been predicted to be among the largest contributors to dose at the time of peak dose from many repositories. Reported here are ³⁶Cl foliar interception, absorption, and translocation parameters for three crops: a root vegetable -radishes, a fruit - beans, and a grain - wheat. Close

• 33. [Article] Improving nitrogen management with cover crops in organic broccoli production

  Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing ...

  Citation × Citation Citation Abstract Copy Title: Improving nitrogen management with cover crops in organic broccoli production Author: Garrett, Amy (Amy Michelle) Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing N mineralization from organic materials with the needs of the subsequent crop is a challenge for organic growers. Predicting plant available nitrogen from cover crop residue enables N fertilizer inputs to be adjusted for optimum economic yield and reduced environmental risk. An experiment was conducted near Corvallis, OR in 2006 through 2008 to evaluate cover crop and N effects in organic broccoli production in western Oregon. The specific objectives of this experiment were to: 1) evaluate biomass production and N accumulation from selected cover crop treatments; 2) compare the effects of selected cover crops grown as sole crops and as mixtures on broccoli yield, yield components, and net economic benefit; 3) estimate the quantity of feather meal N replaced by cover crops 4) estimate plant available nitrogen from cover crop residue in an organic broccoli production system; 5) evaluate soil NO₃₋N and petiole NO₃₋N as predictors of broccoli yield; and 6) evaluate models derived from laboratory incubation of cover crop residue to predict apparent nitrogen recovery (ANR) from cover crop residue in the field. The cover crop treatments included common vetch (Vicia sativa), phacelia (Phacelia tanacetifolia), 'Monida' oats (Avena sativa L.), phacelia plus common vetch, and 'Monida' oats plus common vetch. A fallow treatment was used as the control. Prior to incorporation, cover crop samples were collected from each block and frozen for later use in laboratory aerobic incubations. After the cover crops were flail-mowed and incorporated, four N rates (0, 100, 200, and 300 kg N ha⁻¹) were randomized within each cover crop treatment in a split plot design. All cover crop treatments produced much less biomass and accumulated less N in 2008 than in 2007. Planting vetch with oats or phacelia increased biomass production and N accumulation compared to sole crops in 2007 but not in 2008. Common vetch as a sole crop or in a mixture increased broccoli yield with 0 and 100 kg N ha⁻¹ applied compared to fallow. Legume cover crop mixtures with 100 kg N ha⁻¹ produced similar net economic returns for organic compared to fallow treatments with 300 kg N ha⁻¹. Nitrogen fertilizer input can be reduced by at least 100 kg N ha⁻¹ if common vetch is in the mixture and produces more than 5000 kg ha⁻¹ of biomass (130-180 kg N ha⁻¹). Vetch as a sole crop produced higher levels of soil NO₃₋N than the fallow treatments up to 80 days after soil incorporation in 2007. Oats and phacelia as sole crops, however, reduced soil NO₃₋N compared to fallow for up to 68 days after incorporation. Vetch mixtures with oats or phacelia produced intermediate levels of soil NO₃₋N between vetch as a sole crop and the fallow. Treatment effects were similar in 2008, but differences were less due to reduced cover crop biomass compared to 2007. Broccoli petiole nitrate levels were not affected by cover crop treatment in 2007, and there was no correlation with yield. In 2008, the oat cover crop treatment reduced broccoli petiole nitrate levels compared to the fallow. Petiole nitrate levels were strongly correlated with broccoli yield, with highest yields associated with petiole NO₃₋ N greater than 10,000 ppm. In the aerobic incubations with cover crop mixtures, a quadratic model described the relationship of percent N in the mixture to the apparent nitrogen recovery (ANR) at both 4 and 10 weeks. The highest ANR (about 40 percent) was similar for both extraction days. Net mineralization occurred when the percent N of the cover crop mixture was 1.5-1.8 percent. There was a strong correlation in 2007 between the ANR predicted by the incubation-derived model and the ANR in the soil and in the aboveground broccoli biomass. The model over predicted the ANR in the field soil, however the model more accurately predicted ANR in the broccoli biomass. The incubation model correctly predicted negative ANR values for the oat and phacelia cover-crop treatments. In 2008, the laboratory-predicted ANR and the field soil ANR were correlated (r²=.45), and the laboratory model over predicted the field ANR. The incubation model gave a poor prediction of broccoli biomass ANR. Title: Improving nitrogen management with cover crops in organic broccoli production Author: Garrett, Amy (Amy Michelle) Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing N mineralization from organic materials with the needs of the subsequent crop is a challenge for organic growers. Predicting plant available nitrogen from cover crop residue enables N fertilizer inputs to be adjusted for optimum economic yield and reduced environmental risk. An experiment was conducted near Corvallis, OR in 2006 through 2008 to evaluate cover crop and N effects in organic broccoli production in western Oregon. The specific objectives of this experiment were to: 1) evaluate biomass production and N accumulation from selected cover crop treatments; 2) compare the effects of selected cover crops grown as sole crops and as mixtures on broccoli yield, yield components, and net economic benefit; 3) estimate the quantity of feather meal N replaced by cover crops 4) estimate plant available nitrogen from cover crop residue in an organic broccoli production system; 5) evaluate soil NO₃₋N and petiole NO₃₋N as predictors of broccoli yield; and 6) evaluate models derived from laboratory incubation of cover crop residue to predict apparent nitrogen recovery (ANR) from cover crop residue in the field. The cover crop treatments included common vetch (Vicia sativa), phacelia (Phacelia tanacetifolia), 'Monida' oats (Avena sativa L.), phacelia plus common vetch, and 'Monida' oats plus common vetch. A fallow treatment was used as the control. Prior to incorporation, cover crop samples were collected from each block and frozen for later use in laboratory aerobic incubations. After the cover crops were flail-mowed and incorporated, four N rates (0, 100, 200, and 300 kg N ha⁻¹) were randomized within each cover crop treatment in a split plot design. All cover crop treatments produced much less biomass and accumulated less N in 2008 than in 2007. Planting vetch with oats or phacelia increased biomass production and N accumulation compared to sole crops in 2007 but not in 2008. Common vetch as a sole crop or in a mixture increased broccoli yield with 0 and 100 kg N ha⁻¹ applied compared to fallow. Legume cover crop mixtures with 100 kg N ha⁻¹ produced similar net economic returns for organic compared to fallow treatments with 300 kg N ha⁻¹. Nitrogen fertilizer input can be reduced by at least 100 kg N ha⁻¹ if common vetch is in the mixture and produces more than 5000 kg ha⁻¹ of biomass (130-180 kg N ha⁻¹). Vetch as a sole crop produced higher levels of soil NO₃₋N than the fallow treatments up to 80 days after soil incorporation in 2007. Oats and phacelia as sole crops, however, reduced soil NO₃₋N compared to fallow for up to 68 days after incorporation. Vetch mixtures with oats or phacelia produced intermediate levels of soil NO₃₋N between vetch as a sole crop and the fallow. Treatment effects were similar in 2008, but differences were less due to reduced cover crop biomass compared to 2007. Broccoli petiole nitrate levels were not affected by cover crop treatment in 2007, and there was no correlation with yield. In 2008, the oat cover crop treatment reduced broccoli petiole nitrate levels compared to the fallow. Petiole nitrate levels were strongly correlated with broccoli yield, with highest yields associated with petiole NO₃₋ N greater than 10,000 ppm. In the aerobic incubations with cover crop mixtures, a quadratic model described the relationship of percent N in the mixture to the apparent nitrogen recovery (ANR) at both 4 and 10 weeks. The highest ANR (about 40 percent) was similar for both extraction days. Net mineralization occurred when the percent N of the cover crop mixture was 1.5-1.8 percent. There was a strong correlation in 2007 between the ANR predicted by the incubation-derived model and the ANR in the soil and in the aboveground broccoli biomass. The model over predicted the ANR in the field soil, however the model more accurately predicted ANR in the broccoli biomass. The incubation model correctly predicted negative ANR values for the oat and phacelia cover-crop treatments. In 2008, the laboratory-predicted ANR and the field soil ANR were correlated (r²=.45), and the laboratory model over predicted the field ANR. The incubation model gave a poor prediction of broccoli biomass ANR. Close

• 34. [Article] A production function analysis of water resource productivity in Pacific Northwest agriculture

  The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This ...

  Citation × Citation Citation Abstract Copy Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been, in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data surce, supplemented by related U.S. Department of Agriculture publications, and various state publications, Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large, projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been, in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data surce, supplemented by related U.S. Department of Agriculture publications, and various state publications, Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large, projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Close

• 35. [Article] A production function analysis of water resource productivity in Pacific Northwest agriculture

  The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This ...

  Citation × Citation Citation Abstract Copy Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data source, supplemented by related. U. S. Department of Agriculture publications, and various state publications. Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data source, supplemented by related. U. S. Department of Agriculture publications, and various state publications. Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Close

• 36. [Article] Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars

  This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and ...

  Citation × Citation Citation Abstract Copy Title: Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars Author: Gomez-Pando, Luz This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and 2) to evaluate the possible association between grain yield and grain protein as influenced by different cultivars, nitrogen levels and available moisture. Five wheat and four barley cultivars were selected based on their diverse genetic backgrounds and potential differences for the 12 attributes measured. These experimental materials were grown at low and high rainfall sites and under two different nitrogen levels. In wheat a decrease in the percentage of nitrogen in the flag leaves was found as the plants developed. The highest values were observed at the boot stage. In contrast, the highest percentage of nitrogen in the flag leaves of barley was observed at anthesis. Wheat cultivars which had the greatest genetic potential for grain protein usually had the highest percentage of nitrogen in the flag leaves at the boot stage and the lowest percentage in the vegetative tissue at harvest. This was especially true under high rainfall conditions. A similar relationship was found for the barley cultivars. At both experimental sites higher grain yields were accompanied by negative associations with grain protein for wheat. However, for barley no association was found between these two traits at either site or fertility level. Higher grain protein values were found for both wheat and barley at the high rainfall site. Title: Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars Author: Gomez-Pando, Luz This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and 2) to evaluate the possible association between grain yield and grain protein as influenced by different cultivars, nitrogen levels and available moisture. Five wheat and four barley cultivars were selected based on their diverse genetic backgrounds and potential differences for the 12 attributes measured. These experimental materials were grown at low and high rainfall sites and under two different nitrogen levels. In wheat a decrease in the percentage of nitrogen in the flag leaves was found as the plants developed. The highest values were observed at the boot stage. In contrast, the highest percentage of nitrogen in the flag leaves of barley was observed at anthesis. Wheat cultivars which had the greatest genetic potential for grain protein usually had the highest percentage of nitrogen in the flag leaves at the boot stage and the lowest percentage in the vegetative tissue at harvest. This was especially true under high rainfall conditions. A similar relationship was found for the barley cultivars. At both experimental sites higher grain yields were accompanied by negative associations with grain protein for wheat. However, for barley no association was found between these two traits at either site or fertility level. Higher grain protein values were found for both wheat and barley at the high rainfall site. Close

• 37. [Article] Developing Winter Food Barley for the Pacific Northwest of the US

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesoci...

  Citation × Citation Citation Abstract Copy Title: Developing Winter Food Barley for the Pacific Northwest of the US Author: Kongraksawech, Teepakorn, Meints, Brigid, Cuesta-Marcos, Alfonso, Hayes, Patrick M., Marshall, Juliet M., Fisk, Scott, Ross, Andrew S., Murphy, Kevin This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Title: Developing Winter Food Barley for the Pacific Northwest of the US Author: Kongraksawech, Teepakorn, Meints, Brigid, Cuesta-Marcos, Alfonso, Hayes, Patrick M., Marshall, Juliet M., Fisk, Scott, Ross, Andrew S., Murphy, Kevin This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Close

• 38. [Article] Yield and quality of cereals for winter silage production

  A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the ...

  Citation × Citation Citation Abstract Copy Title: Yield and quality of cereals for winter silage production Author: Ben Ali, Mohamed Noureddine A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the context of a corn-winter cemal double cropping production system. Data on the yield, crude protein (CP) content, acid and neutral detergent fiber (ADF and NDF) contents were collected on Adair, Casbon and FB 73130 barley (Hordeum vulgare L.) varieties, Amity, Cayuse and Grey winter oats (Avena Sativa L.), Abruzi and Kung rye (Secale cereale L.), S-72, Sel N-91 and VT 75-229 Triticale (Triticum X Secale) and Stephens and Yamhill wheat (Triticum Aestivum L.) varieties. The statistical analysis of the data gave the following results. Dry matter yields ranged on the average from a high of 8327 kg/ha to a low of 4631 ka/ha. Abruzi rye generally yielded the most dry matter. It was followed by Sel N-91 and VT 75-229 Triticales, Kung rye, S-72 Triticale and the wheat varieties. The barley and oats varieties were generally the lowest producers. Crude protein content was within the range of 6,5 to 10.1 percent of the dry matter. It was on the average highest for FB 73130 barley followed by Casbon barley, Stephens wheat, Adair barley, Yamhill wheat and the Triticale varieties. Acid detergent fiber ranged from 30.8 to 46.4 percent of dry matter. The oats varieties had the lowest ADF values, followed by Stephens and Yamhill wheats, FB 73130 and Adair barleys and VT 75-229 Triticale. The average neutral detergent fiber content for the 13 cereal varieties varied from a low of 50.3 to a high of 69.4 percent of D.M. The oats varieties were generally lowest followed by Stephens and Yamhill wheats, FB 73130 barley, VT 75-229 Triticale, Adair barley and Sel N-91 and S-72 Triticales. Covariance analysis indicated that a strong linear relationship existed between the yield and the quality components of the cereal varieties. When CP, ADF and NDF contents were adjusted for the same yield, it was found that the nitrogen fertilizer effect was no longer significant for either ADF or NDF. Title: Yield and quality of cereals for winter silage production Author: Ben Ali, Mohamed Noureddine A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the context of a corn-winter cemal double cropping production system. Data on the yield, crude protein (CP) content, acid and neutral detergent fiber (ADF and NDF) contents were collected on Adair, Casbon and FB 73130 barley (Hordeum vulgare L.) varieties, Amity, Cayuse and Grey winter oats (Avena Sativa L.), Abruzi and Kung rye (Secale cereale L.), S-72, Sel N-91 and VT 75-229 Triticale (Triticum X Secale) and Stephens and Yamhill wheat (Triticum Aestivum L.) varieties. The statistical analysis of the data gave the following results. Dry matter yields ranged on the average from a high of 8327 kg/ha to a low of 4631 ka/ha. Abruzi rye generally yielded the most dry matter. It was followed by Sel N-91 and VT 75-229 Triticales, Kung rye, S-72 Triticale and the wheat varieties. The barley and oats varieties were generally the lowest producers. Crude protein content was within the range of 6,5 to 10.1 percent of the dry matter. It was on the average highest for FB 73130 barley followed by Casbon barley, Stephens wheat, Adair barley, Yamhill wheat and the Triticale varieties. Acid detergent fiber ranged from 30.8 to 46.4 percent of dry matter. The oats varieties had the lowest ADF values, followed by Stephens and Yamhill wheats, FB 73130 and Adair barleys and VT 75-229 Triticale. The average neutral detergent fiber content for the 13 cereal varieties varied from a low of 50.3 to a high of 69.4 percent of D.M. The oats varieties were generally lowest followed by Stephens and Yamhill wheats, FB 73130 barley, VT 75-229 Triticale, Adair barley and Sel N-91 and S-72 Triticales. Covariance analysis indicated that a strong linear relationship existed between the yield and the quality components of the cereal varieties. When CP, ADF and NDF contents were adjusted for the same yield, it was found that the nitrogen fertilizer effect was no longer significant for either ADF or NDF. Close

• 39. [Article] Estimating plant-available nitrogen release from cover crops

  Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Estimating plant-available nitrogen release from cover crops Author: Andrews, N. (Nick), Oregon State University. Extension Service, Sullivan, Dan M. (Dan Matthew), 1954- Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Estimating plant-available nitrogen release from cover crops Author: Andrews, N. (Nick), Oregon State University. Extension Service, Sullivan, Dan M. (Dan Matthew), 1954- Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 40. [Article] Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach

  The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program ...

  Citation × Citation Citation Abstract Copy Title: Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach Author: Mahrouf, Abdul R. M. The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program in Mahaweli System B, Sri Lanka. The adoption of new cropping patterns is determined by a number of interrelated and mutually reinforcing factors. Hence, a multidisciplinary approach is used in this study to apprehend the different attributes of the new cropping patterns and farmers' decision making environment. The analytical methods include Marginal Cost-Benefit Analysis, Multivariate Analysis of Variance, Factor Analysis and Logit Probability Model. The results from the different techniques are generally in close agreement and complement each other. Results of the Marginal Cost- Benefit Analysis indicates that an increase in current crop yields and output prices may be necessary to increase the profitability of new cropping patterns to a recommendable level. Analysis of the farmers' beliefs suggests that adopters of the new cropping patterns have more positive beliefs towards the profitability and adoption of new cropping patterns when compared to nonadopters. Factor Analysis shows that there is a wide variation between the adopters and non-adopters, and also across the different locations with respect to farm-level variables. The analysis demonstrated that the information provided by 17 selected farm-level variables may be explained by four factors; namely, management factor, social factor, farm resource factor and farm stability factor. The variables highly loaded with the stability factor (number of years of residence, amount of loan obtained for farming, irrigation condition and percentage of rice produced allocated for consumption) are closely associated with the adoption rate. A logit probability model indicates that availability of farm loans significantly increases the probability of the adoption of new cropping patterns. The study results show that the crop yield, output prices, availability of farm loans and farmer beliefs, are the dominant factors which influence the adoption of new cropping patterns. Title: Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach Author: Mahrouf, Abdul R. M. The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program in Mahaweli System B, Sri Lanka. The adoption of new cropping patterns is determined by a number of interrelated and mutually reinforcing factors. Hence, a multidisciplinary approach is used in this study to apprehend the different attributes of the new cropping patterns and farmers' decision making environment. The analytical methods include Marginal Cost-Benefit Analysis, Multivariate Analysis of Variance, Factor Analysis and Logit Probability Model. The results from the different techniques are generally in close agreement and complement each other. Results of the Marginal Cost- Benefit Analysis indicates that an increase in current crop yields and output prices may be necessary to increase the profitability of new cropping patterns to a recommendable level. Analysis of the farmers' beliefs suggests that adopters of the new cropping patterns have more positive beliefs towards the profitability and adoption of new cropping patterns when compared to nonadopters. Factor Analysis shows that there is a wide variation between the adopters and non-adopters, and also across the different locations with respect to farm-level variables. The analysis demonstrated that the information provided by 17 selected farm-level variables may be explained by four factors; namely, management factor, social factor, farm resource factor and farm stability factor. The variables highly loaded with the stability factor (number of years of residence, amount of loan obtained for farming, irrigation condition and percentage of rice produced allocated for consumption) are closely associated with the adoption rate. A logit probability model indicates that availability of farm loans significantly increases the probability of the adoption of new cropping patterns. The study results show that the crop yield, output prices, availability of farm loans and farmer beliefs, are the dominant factors which influence the adoption of new cropping patterns. Close