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• 71. [Article] High-context and low-context cultures: value system variations for American and Japanese university students and their resultant communication patterns

  This exploratory investigation focused on the validity of the concepts of high-context and low-context as a meaningful and powerful construct for examining cultural differences. Specifically, American ...

  Citation × Citation Citation Abstract Copy Title: High-context and low-context cultures: value system variations for American and Japanese university students and their resultant communication patterns Author: Yamaguchi, Shinobu Yume This exploratory investigation focused on the validity of the concepts of high-context and low-context as a meaningful and powerful construct for examining cultural differences. Specifically, American and Japanese value differences and communication patterns were examined. The study tested the hypotheses that Japanese students would rank high-context group orientation values higher than American students, and American students would rank low-context individual values higher than Japanese students. Other value differences and similarities were explored. The data were collected from American university students and Japanese university students. Subjects were drawn from Oregon State University for American students, and from Aoyama Gakuin University in Tokyo for Japanese students. Statistical analysis of rank order data showed Japanese university students ranked highly on group orientation values, supporting the first hypothesis, while American university students ranked highly on individual orientation values, supporting the second hypothesis. The general results of this exploratory study were interpreted as supporting Hall's concepts of high-context and low-context cultural differences. Title: High-context and low-context cultures: value system variations for American and Japanese university students and their resultant communication patterns Author: Yamaguchi, Shinobu Yume This exploratory investigation focused on the validity of the concepts of high-context and low-context as a meaningful and powerful construct for examining cultural differences. Specifically, American and Japanese value differences and communication patterns were examined. The study tested the hypotheses that Japanese students would rank high-context group orientation values higher than American students, and American students would rank low-context individual values higher than Japanese students. Other value differences and similarities were explored. The data were collected from American university students and Japanese university students. Subjects were drawn from Oregon State University for American students, and from Aoyama Gakuin University in Tokyo for Japanese students. Statistical analysis of rank order data showed Japanese university students ranked highly on group orientation values, supporting the first hypothesis, while American university students ranked highly on individual orientation values, supporting the second hypothesis. The general results of this exploratory study were interpreted as supporting Hall's concepts of high-context and low-context cultural differences. Close

• 72. [Article] Ethical Considerations of Transgenic Biotechnology as a Tool to Address Global Food Insecurity: Implementation and Regulation in Developing Countries

  Transgenic biotechnology holds enormous potential as a tool to address global food insecurity. Transgenic food crops have been shown to increase food availability and food system security by incorporating ...

  Citation × Citation Citation Abstract Copy Title: Ethical Considerations of Transgenic Biotechnology as a Tool to Address Global Food Insecurity: Implementation and Regulation in Developing Countries Author: Stepper, Shelby Ann Transgenic biotechnology holds enormous potential as a tool to address global food insecurity. Transgenic food crops have been shown to increase food availability and food system security by incorporating disease, pesticide and drought resistance. Production costs of transgenic crops are lower due to the reduced need for costly pesticides and manual tillage, leaving more disposable income for farmers to buy food. Biofortified and nutritionally enriched transgenic crops may be able to reduce vitamin and micronutrient deficiencies. Despite the many promising applications of transgenic food crops in developing countries, many governments have raised major objections to the utilization of transgenic food production and have resisted transgenic crop adoption. The majority of these objections appear to be rooted in societal values, economics related to trade, and ethical principles, not biophysical science. My analysis of the current regulatory system suggests that ethical considerations regarding transgenic food crops are best addressed as part of local regulations rather than incorporated in global trade restrictions. I argue that while there is no silver bullet for solving world hunger, the utilization and responsible regulation of biotechnology could meaningfully contribute its reduction. Title: Ethical Considerations of Transgenic Biotechnology as a Tool to Address Global Food Insecurity: Implementation and Regulation in Developing Countries Author: Stepper, Shelby Ann Transgenic biotechnology holds enormous potential as a tool to address global food insecurity. Transgenic food crops have been shown to increase food availability and food system security by incorporating disease, pesticide and drought resistance. Production costs of transgenic crops are lower due to the reduced need for costly pesticides and manual tillage, leaving more disposable income for farmers to buy food. Biofortified and nutritionally enriched transgenic crops may be able to reduce vitamin and micronutrient deficiencies. Despite the many promising applications of transgenic food crops in developing countries, many governments have raised major objections to the utilization of transgenic food production and have resisted transgenic crop adoption. The majority of these objections appear to be rooted in societal values, economics related to trade, and ethical principles, not biophysical science. My analysis of the current regulatory system suggests that ethical considerations regarding transgenic food crops are best addressed as part of local regulations rather than incorporated in global trade restrictions. I argue that while there is no silver bullet for solving world hunger, the utilization and responsible regulation of biotechnology could meaningfully contribute its reduction. Close

• 73. [Article] Ethanol and High-Value Terpene Co-Production from Lignocellulosic Biomass of Cymbopogon flexuosus and Cymbopogon martinii

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library ...

  Citation × Citation Citation Abstract Copy Title: Ethanol and High-Value Terpene Co-Production from Lignocellulosic Biomass of Cymbopogon flexuosus and Cymbopogon martinii Author: Sykes, Robert, Joyce, Blake L., et al., Zheljazkov, Valtcho D. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Title: Ethanol and High-Value Terpene Co-Production from Lignocellulosic Biomass of Cymbopogon flexuosus and Cymbopogon martinii Author: Sykes, Robert, Joyce, Blake L., et al., Zheljazkov, Valtcho D. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Close

• 74. [Article] Evaporation synergy in a bi-textured soil system

  Evaporation synergy is the phenomenon in which two porous medium textures that share a common vertical boundary experience a higher cumulative evaporation than either homogeneous texture can produce. Studies ...

  Citation × Citation Citation Abstract Copy Title: Evaporation synergy in a bi-textured soil system Author: Fisher, Arthur J. Evaporation synergy is the phenomenon in which two porous medium textures that share a common vertical boundary experience a higher cumulative evaporation than either homogeneous texture can produce. Studies that have been conducted to date address this phenomenon in relatively fine and coarse sands but not in finer textured soils where viscous forces play a major role. The purpose of this study was to determine which of the 66 combinations of soil textures would exhibit evaporation synergy and develop a conceptual model of the conditions necessary for synergy. The numerical modeler HYDRUS was used to investigate all soil texture combinations and generate evaporation rates and cumulative evaporation amounts for each system. In addition, two combinations of soils were selected as laboratory experiments based on the HYDRUS predictions: one that exhibited synergy (Loamy Sand & Silt Loam) and one that did not (Loamy Sand & Sandy Clay). The laboratory data supported the HYDRUS predictions for evaporation synergy and non-synergy. The conditions necessary for evaporation synergy were developed from the numerical and physical models’ predictions and results. The two textures must experience different air-entry values to create lateral and vertical pressure gradients, the fine must possess a high enough hydraulic conductivity to allow water to move to its surface before it reaches its own air-entry value and possess the capillarity to maintain liquid film flow to its surface, and the viscous forces within the coarse must be low enough for water to be pulled from itself to the fine. It was also determined that the evaporation rate of a bi-texture decreases as a series of constant-rate steps until the fine enters S2 evaporation and is associated with a stepwise recession of the drying front in the coarse media. The duration of each step appears to be associated with the lateral distance from which water can be extracted within the coarse media. Title: Evaporation synergy in a bi-textured soil system Author: Fisher, Arthur J. Evaporation synergy is the phenomenon in which two porous medium textures that share a common vertical boundary experience a higher cumulative evaporation than either homogeneous texture can produce. Studies that have been conducted to date address this phenomenon in relatively fine and coarse sands but not in finer textured soils where viscous forces play a major role. The purpose of this study was to determine which of the 66 combinations of soil textures would exhibit evaporation synergy and develop a conceptual model of the conditions necessary for synergy. The numerical modeler HYDRUS was used to investigate all soil texture combinations and generate evaporation rates and cumulative evaporation amounts for each system. In addition, two combinations of soils were selected as laboratory experiments based on the HYDRUS predictions: one that exhibited synergy (Loamy Sand & Silt Loam) and one that did not (Loamy Sand & Sandy Clay). The laboratory data supported the HYDRUS predictions for evaporation synergy and non-synergy. The conditions necessary for evaporation synergy were developed from the numerical and physical models’ predictions and results. The two textures must experience different air-entry values to create lateral and vertical pressure gradients, the fine must possess a high enough hydraulic conductivity to allow water to move to its surface before it reaches its own air-entry value and possess the capillarity to maintain liquid film flow to its surface, and the viscous forces within the coarse must be low enough for water to be pulled from itself to the fine. It was also determined that the evaporation rate of a bi-texture decreases as a series of constant-rate steps until the fine enters S2 evaporation and is associated with a stepwise recession of the drying front in the coarse media. The duration of each step appears to be associated with the lateral distance from which water can be extracted within the coarse media. Close

• 75. [Article] Geostatistical applications to salinity mapping and simulated reclamation

  Geostatistical methods were used to find efficient and accurate means for salinity assessment using regionalized random variables and limited sampling. The random variables selected, sodium absorption ...

  Citation × Citation Citation Abstract Copy Title: Geostatistical applications to salinity mapping and simulated reclamation Author: Al-Taher, Mohamad A. Geostatistical methods were used to find efficient and accurate means for salinity assessment using regionalized random variables and limited sampling. The random variables selected, sodium absorption ratio (SAR), electrical conductivity (EC), and clay content were measured on samples taken over an area of fifteen square miles. Ordinary kriging and co-kriging were used as linear estimators. They were compared on the basis of average kriging variance and sum of squares for error between observed and estimated values. The results indicate a significant improvement in the average kriging variance and sum of squares by using co-kriging estimators. EC was used to estimate SAR because of the high correlation between them. This was not true for clay content. A saving of two-thirds of the cost and time was achieved by using electrical conductivity as an auxiliary variable to estimate sodium absorption ratio. The nonlinear estimator, disjunctive kriging, was an improvement over co-kriging in terms of the variances. More information at the estimation site is a more important consideration than when the estimator is linear. Disjunctive kriging was used to produce an estimate of the conditional probability that the value at an unsampled location is greater than an arbitrary cutoff level. This feature of disjunctive kriging aids salinity assessment and reclamation management. A solute transport model was used to show how saptially variable initial conditions influenced the amount of water required to reclaim a saline soil at each sampling point in a simulated leaching of the area. Title: Geostatistical applications to salinity mapping and simulated reclamation Author: Al-Taher, Mohamad A. Geostatistical methods were used to find efficient and accurate means for salinity assessment using regionalized random variables and limited sampling. The random variables selected, sodium absorption ratio (SAR), electrical conductivity (EC), and clay content were measured on samples taken over an area of fifteen square miles. Ordinary kriging and co-kriging were used as linear estimators. They were compared on the basis of average kriging variance and sum of squares for error between observed and estimated values. The results indicate a significant improvement in the average kriging variance and sum of squares by using co-kriging estimators. EC was used to estimate SAR because of the high correlation between them. This was not true for clay content. A saving of two-thirds of the cost and time was achieved by using electrical conductivity as an auxiliary variable to estimate sodium absorption ratio. The nonlinear estimator, disjunctive kriging, was an improvement over co-kriging in terms of the variances. More information at the estimation site is a more important consideration than when the estimator is linear. Disjunctive kriging was used to produce an estimate of the conditional probability that the value at an unsampled location is greater than an arbitrary cutoff level. This feature of disjunctive kriging aids salinity assessment and reclamation management. A solute transport model was used to show how saptially variable initial conditions influenced the amount of water required to reclaim a saline soil at each sampling point in a simulated leaching of the area. Close

• 76. [Article] Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States

  Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other ...

  Citation × Citation Citation Abstract Copy Title: Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States Author: Abdel-Karim, Ibrahim Amin Year: 1987 Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other factors which are not only prevalent in developed world economies, but which also are thought to force the cultivation of freshly consumed agricultural commodities away from the immediate vicinity of the market center. The second issue pertains to indirectly consumed crops, which are thought to shun proximity to the market center, where land rents per unit area are characteristically high, even when conditions for productions are ideal. Traditional models have shown a zonal pattern of crop distribution in peri-urban areas. The present study sets forth two hypotheses, one pertaining to the spatial distribution of freshly consumed crops, and the other pertaining to the spatial distribution of indirectly consumed crops. It was hypothesized in the present study that freshly consumed crops will continue to be cultivated in the near vicinity of the market center due to characteristics of the crops and the urban market. It was further hypothesized that indirectly consumed crops will continue to be cultivated in the near vicinity of the market center by virtue of greater intensity of production that may be obtained through the use of the environment of designated places. In the case of both crops, the cited factors, as well as others, offset the disadvantages of higher land rent per unit area common to areas close to the market center. These offsetting factors permit agriculture to compete successfully for land in the peri-urban zone. To test these hypotheses, variables were selected to measure the influence that urbanization, transportation, other technologies, the market, the environment, and land use regulations have on agricultural siting patterns in the peri-urban zones of the "Wheat Region" of the central United States. These variables were expressed as equations and were subjected to multiple linear regression (MLR) analysis. The present findings tended to support the research hypotheses. On the basis of these findings, the present research offers a revised model of agricultural cropping patterns, one that reflects the sectoral, rather than the zonal, pattern of crop distribution in peri-urban zones. In the revised model, the mixing of different crops at various locations around the market is feasible, and low-priced grains may compete successfully for high-rent locations in the near vicinity of the urban market. The findings also show that the production of perishable crops in the iIl'.mediate vicinity of the urban market is here to stay, largely due to access to varied means of transportation as well as characteristics of the crops themselves. Furthermore, the findings show that environmental conditions influence the locating of grain production, although economic considerations were seen to supersede them, particularly at high-rent sites. Title: Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States Author: Abdel-Karim, Ibrahim Amin Year: 1987 Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other factors which are not only prevalent in developed world economies, but which also are thought to force the cultivation of freshly consumed agricultural commodities away from the immediate vicinity of the market center. The second issue pertains to indirectly consumed crops, which are thought to shun proximity to the market center, where land rents per unit area are characteristically high, even when conditions for productions are ideal. Traditional models have shown a zonal pattern of crop distribution in peri-urban areas. The present study sets forth two hypotheses, one pertaining to the spatial distribution of freshly consumed crops, and the other pertaining to the spatial distribution of indirectly consumed crops. It was hypothesized in the present study that freshly consumed crops will continue to be cultivated in the near vicinity of the market center due to characteristics of the crops and the urban market. It was further hypothesized that indirectly consumed crops will continue to be cultivated in the near vicinity of the market center by virtue of greater intensity of production that may be obtained through the use of the environment of designated places. In the case of both crops, the cited factors, as well as others, offset the disadvantages of higher land rent per unit area common to areas close to the market center. These offsetting factors permit agriculture to compete successfully for land in the peri-urban zone. To test these hypotheses, variables were selected to measure the influence that urbanization, transportation, other technologies, the market, the environment, and land use regulations have on agricultural siting patterns in the peri-urban zones of the "Wheat Region" of the central United States. These variables were expressed as equations and were subjected to multiple linear regression (MLR) analysis. The present findings tended to support the research hypotheses. On the basis of these findings, the present research offers a revised model of agricultural cropping patterns, one that reflects the sectoral, rather than the zonal, pattern of crop distribution in peri-urban zones. In the revised model, the mixing of different crops at various locations around the market is feasible, and low-priced grains may compete successfully for high-rent locations in the near vicinity of the urban market. The findings also show that the production of perishable crops in the iIl'.mediate vicinity of the urban market is here to stay, largely due to access to varied means of transportation as well as characteristics of the crops themselves. Furthermore, the findings show that environmental conditions influence the locating of grain production, although economic considerations were seen to supersede them, particularly at high-rent sites. Close

• 77. [Article] Interaction of crop plant population with weed competition in corn (Zea mays L.), bush snap beans (Phaseolus vulgaris L.), and onion (Allium cepa L.) at differing stages of development

  Yield reductions due to competition of weeds with crop plants can be extremely important. Early weed competition can be as important in reducing crop yield as weed competition for the entire season. The ...

  Citation × Citation Citation Abstract Copy Title: Interaction of crop plant population with weed competition in corn (Zea mays L.), bush snap beans (Phaseolus vulgaris L.), and onion (Allium cepa L.) at differing stages of development Author: Williams, Clarence Frank Yield reductions due to competition of weeds with crop plants can be extremely important. Early weed competition can be as important in reducing crop yield as weed competition for the entire season. The objectives of this study were (1) to determine the weed control achieved by narrow row-cropping patterns, (2) to measure the competitive effect achieved with narrow row-cropping patterns, with low photosynthetic capacity crop plants or with high photosynthetic capacity plants, in competition with high photosynthetic capacity weeds, (3) to determine at what time weed control becomes important and (4) to determine if the time at which competition begins could be determined by change in weight, sugar content, and/or nitrogen content of the commercial crop. Also, two greenhouse studies were made to evaluate the differential uptake of nitrogen by two competiting species, corn (Zea mays L.) and pigweed (Amaranthus rectroflexus L.), and to evaluate the effect of competition for soil and light between two broadleaf species, snap beans and pigweed. Yields of bush snap beans (Phaseolus vulgaris L.), corn (Zea mays L.), and onion (Allium cepa L.) were all decreased significantly by the presence of weed competition throughout the entire growing season. Reduction in total area occupied by an individual crop plant resulted in decreased effects on vegetative and reproductive parts due to weed competition and increased the effect of crop plant-to-plant competition. Early weed control was important in all crops. In 1969, yield reductions in corn and beans allowed, to compete with weeds for a period of five to six weeks after crop emergence were equal to those from plots with weed competition for the entire season. In 1970, corn required two weeks of cultivation after emergence and snap beans required three weeks of cultivation after emergence to decrease losses due to weed competition. Weed weight yields were significantly reduced in snap beans at the 5 x 5 inch spacing when compared to the 15 x 5 and 35 x 5 inch spacings. As measured by leaf fresh weight, competition was determined to begin between snap beans and redroot pigweed at 36 to 44 days after crop emergence at crop plant spacings of 35 x 5 and 15 x 5 inches. Significant weed competition did not develop after 51 days at crop plant spacings of 5 x 5 inches. Competition between corn and redroot developed 41 days after emergence for all plant spacings. This study indicated the time at which competition between crop and weeds could be determined by leaf fresh weight measurements or by measuring the leaf area of the crop plants. At a fertilizer rate of 77-101-64 pounds of N-P-K per acre, corn made greater gains in total green weight than did pigweed in the greenhouse. However, with the further addition of 300 pounds of ammonium nitrate per acre, pigweed continued to make gains while corn growth was unaffected. At all fertility rates, pigweed had higher levels of total leaf nitrogen than corn. When snap beans had emerged and become established before the emergence of pigweed, the total green and dry weight of pigweed was significantly reduced if growing in full competition or in competition for soil factors only. Title: Interaction of crop plant population with weed competition in corn (Zea mays L.), bush snap beans (Phaseolus vulgaris L.), and onion (Allium cepa L.) at differing stages of development Author: Williams, Clarence Frank Yield reductions due to competition of weeds with crop plants can be extremely important. Early weed competition can be as important in reducing crop yield as weed competition for the entire season. The objectives of this study were (1) to determine the weed control achieved by narrow row-cropping patterns, (2) to measure the competitive effect achieved with narrow row-cropping patterns, with low photosynthetic capacity crop plants or with high photosynthetic capacity plants, in competition with high photosynthetic capacity weeds, (3) to determine at what time weed control becomes important and (4) to determine if the time at which competition begins could be determined by change in weight, sugar content, and/or nitrogen content of the commercial crop. Also, two greenhouse studies were made to evaluate the differential uptake of nitrogen by two competiting species, corn (Zea mays L.) and pigweed (Amaranthus rectroflexus L.), and to evaluate the effect of competition for soil and light between two broadleaf species, snap beans and pigweed. Yields of bush snap beans (Phaseolus vulgaris L.), corn (Zea mays L.), and onion (Allium cepa L.) were all decreased significantly by the presence of weed competition throughout the entire growing season. Reduction in total area occupied by an individual crop plant resulted in decreased effects on vegetative and reproductive parts due to weed competition and increased the effect of crop plant-to-plant competition. Early weed control was important in all crops. In 1969, yield reductions in corn and beans allowed, to compete with weeds for a period of five to six weeks after crop emergence were equal to those from plots with weed competition for the entire season. In 1970, corn required two weeks of cultivation after emergence and snap beans required three weeks of cultivation after emergence to decrease losses due to weed competition. Weed weight yields were significantly reduced in snap beans at the 5 x 5 inch spacing when compared to the 15 x 5 and 35 x 5 inch spacings. As measured by leaf fresh weight, competition was determined to begin between snap beans and redroot pigweed at 36 to 44 days after crop emergence at crop plant spacings of 35 x 5 and 15 x 5 inches. Significant weed competition did not develop after 51 days at crop plant spacings of 5 x 5 inches. Competition between corn and redroot developed 41 days after emergence for all plant spacings. This study indicated the time at which competition between crop and weeds could be determined by leaf fresh weight measurements or by measuring the leaf area of the crop plants. At a fertilizer rate of 77-101-64 pounds of N-P-K per acre, corn made greater gains in total green weight than did pigweed in the greenhouse. However, with the further addition of 300 pounds of ammonium nitrate per acre, pigweed continued to make gains while corn growth was unaffected. At all fertility rates, pigweed had higher levels of total leaf nitrogen than corn. When snap beans had emerged and become established before the emergence of pigweed, the total green and dry weight of pigweed was significantly reduced if growing in full competition or in competition for soil factors only. Close

• 78. [Article] Estimation of genetic-parameters in the Oregon State University Hazelnut (Corylus avellana L.) breeding population

  Heritability in the narrow sense and in the broad sense, variance components and correlation coefficients are important genetic parameters in a breeding program. The estimates of these parameters can provide ...

  Citation × Citation Citation Abstract Copy Title: Estimation of genetic-parameters in the Oregon State University Hazelnut (Corylus avellana L.) breeding population Author: Yao, Qiang Heritability in the narrow sense and in the broad sense, variance components and correlation coefficients are important genetic parameters in a breeding program. The estimates of these parameters can provide important information for a breeder in the selection of parents, the most efficient design for evaluation of seedlings and advanced selections and the choice of selection strategy to improve many target traits simultaneously. In addition, histograms showing the distributions of the traits in offspring may provide additional information about parent combinations for the improvement of target traits. The Oregon State University hazelnut breeding program is developing improved varieties for the kernel market. Estimates of genetic parameters for most traits of interest are not available. Seventy seven trees representing 41 genotypes and 35 progenies were used to investigate midparent values and progeny means for 17 traits, including 13 kernel and nut traits, and 4 phenological traits, for three years. Estimates for heritability in the narrow sense are all high, ranging from 0.56 for amount of kernel fiber, and 0.58 for date of opening of female flowers to 0.87 for percent kernel, 0.88 for nut compression index and 0.89 for nut depth. Therefore, progeny means can be predicted from mid-parent values and response to selection is expected to be rapid for the improvement of all traits. The analysis of variance components revealed that genotypic variance accounted for most of the phenotypic variance. Although significant, the genotype X year interaction only accounted for a very small part of the phenotypic variance. It suggested one year's evaluation of genotypes for all traits should be sufficient except for nut weight, kernel weight, number of nuts per cluster, fiber amount, nut maturity, time of catkin elongation, and time of opening of female flowers. Genetic and phenotypic correlation coeficients were large and positive for nut size traits (nut length, width, depth, nut weight and kernel weight). Phenological traits (date of opening of female flowers, time of catkin elongation and time of leafing out) were also highly and positively correlated. But most other traits were uncorrelated with each other. Therefore, selection of parents with round nuts of medium size, high % kernel, easily-blanched kernels, and early nut maturity is expected to rapidly improve the population for all of these traits. Histograms show that all traits have continuous variation. Transgressive segregation is very common. For all traits except blanching ability, parent combinations may be based on midparent values. For the improvement of blanching ability, both parents should blanch easily. Because existing statistical packages do not allow easy calculation of genetic correlation coefficients for tree fruit and nut crops, the use of a spreadsheet to quickly estimate genetic correlation coefficients is demonstrated. Title: Estimation of genetic-parameters in the Oregon State University Hazelnut (Corylus avellana L.) breeding population Author: Yao, Qiang Heritability in the narrow sense and in the broad sense, variance components and correlation coefficients are important genetic parameters in a breeding program. The estimates of these parameters can provide important information for a breeder in the selection of parents, the most efficient design for evaluation of seedlings and advanced selections and the choice of selection strategy to improve many target traits simultaneously. In addition, histograms showing the distributions of the traits in offspring may provide additional information about parent combinations for the improvement of target traits. The Oregon State University hazelnut breeding program is developing improved varieties for the kernel market. Estimates of genetic parameters for most traits of interest are not available. Seventy seven trees representing 41 genotypes and 35 progenies were used to investigate midparent values and progeny means for 17 traits, including 13 kernel and nut traits, and 4 phenological traits, for three years. Estimates for heritability in the narrow sense are all high, ranging from 0.56 for amount of kernel fiber, and 0.58 for date of opening of female flowers to 0.87 for percent kernel, 0.88 for nut compression index and 0.89 for nut depth. Therefore, progeny means can be predicted from mid-parent values and response to selection is expected to be rapid for the improvement of all traits. The analysis of variance components revealed that genotypic variance accounted for most of the phenotypic variance. Although significant, the genotype X year interaction only accounted for a very small part of the phenotypic variance. It suggested one year's evaluation of genotypes for all traits should be sufficient except for nut weight, kernel weight, number of nuts per cluster, fiber amount, nut maturity, time of catkin elongation, and time of opening of female flowers. Genetic and phenotypic correlation coeficients were large and positive for nut size traits (nut length, width, depth, nut weight and kernel weight). Phenological traits (date of opening of female flowers, time of catkin elongation and time of leafing out) were also highly and positively correlated. But most other traits were uncorrelated with each other. Therefore, selection of parents with round nuts of medium size, high % kernel, easily-blanched kernels, and early nut maturity is expected to rapidly improve the population for all of these traits. Histograms show that all traits have continuous variation. Transgressive segregation is very common. For all traits except blanching ability, parent combinations may be based on midparent values. For the improvement of blanching ability, both parents should blanch easily. Because existing statistical packages do not allow easy calculation of genetic correlation coefficients for tree fruit and nut crops, the use of a spreadsheet to quickly estimate genetic correlation coefficients is demonstrated. Close

• 79. [Article] Biochemical evaluation of silage corn varieties

  Chemical and biological evaluations were conducted to provide chemical composition and digestibility information, in addition to yield data, for silage corn varieties produced on poorly drained Dayton ...

  Citation × Citation Citation Abstract Copy Title: Biochemical evaluation of silage corn varieties Author: Anderson, Daniel Craig Chemical and biological evaluations were conducted to provide chemical composition and digestibility information, in addition to yield data, for silage corn varieties produced on poorly drained Dayton soil series. Each variety was subjected to a Kjeldahl nitrogen, acid detergent fiber, acid detergent lignin, cell wall, and residual ash test. Subsequently cell contents, cellulose, and hemicellulose were calculated by difference. The objectives of this study were to determine if significant differences in nutrient composition and digestibility existed among silage corn varieties grown under similar cultural conditions, and whether such differences could be detected by the detergent analysis scheme in a non-pasture forage. Finally, a comparison of in vitro (artificial rumen) and summative equation digestibility coefficients would indicate the possibility of using the latter for estimating nutritive value in forage crop experimental work. In addition, grass and legume samples, varying widely in nutritive value, were subjected to detergent analysis to ascertain the systems capabilities for assessing differences in chemical composition between forage types. Statistical analysis of the data for chemical composition of the silage corn varieties showed that no significant differences among varieties existed at the five percent probability level. Biological availability of the nutrients of the silage corn varieties was measured by the in vitro (artificial rumen) technique. No significant differences were noted in the 24-hour trials. However, in the 12-hour trials varieties two and four gave coefficients that were significantly (P < .05) greater than varieties one, five, six, seven, or ten. Calculated correlations of the 12 and 24-hour in vitro (artificial rumen) dry matter digestibility and of coefficients estimated by the summative equation were not highly significant. Relationships of chemical constituent data of grass and legume samples from detergent analysis provided evidence that this feed-stuff fractionation accurately reflects differences in chemical composition between species. Hemicellulose values of the grass were four times as great as those of the alfalfa, but the cellulose content was similar for the two forage types. Comparison of silage corn data with that of the alfalfa gave a relationship analogous to that of the alfalfa-grass. Residual ash values of the grass were ten times larger than those of the alfalfa. However, it was not an important factor limiting nutritive value in either the alfalfa or the silage corn. Alfalfa cell wall level and its digestibility were lower than that of the grass. But cell wall material of the grass was twice the amount contained in the alfalfa, and its digestibility was also higher which reflects its lower degree of lignification. Title: Biochemical evaluation of silage corn varieties Author: Anderson, Daniel Craig Chemical and biological evaluations were conducted to provide chemical composition and digestibility information, in addition to yield data, for silage corn varieties produced on poorly drained Dayton soil series. Each variety was subjected to a Kjeldahl nitrogen, acid detergent fiber, acid detergent lignin, cell wall, and residual ash test. Subsequently cell contents, cellulose, and hemicellulose were calculated by difference. The objectives of this study were to determine if significant differences in nutrient composition and digestibility existed among silage corn varieties grown under similar cultural conditions, and whether such differences could be detected by the detergent analysis scheme in a non-pasture forage. Finally, a comparison of in vitro (artificial rumen) and summative equation digestibility coefficients would indicate the possibility of using the latter for estimating nutritive value in forage crop experimental work. In addition, grass and legume samples, varying widely in nutritive value, were subjected to detergent analysis to ascertain the systems capabilities for assessing differences in chemical composition between forage types. Statistical analysis of the data for chemical composition of the silage corn varieties showed that no significant differences among varieties existed at the five percent probability level. Biological availability of the nutrients of the silage corn varieties was measured by the in vitro (artificial rumen) technique. No significant differences were noted in the 24-hour trials. However, in the 12-hour trials varieties two and four gave coefficients that were significantly (P < .05) greater than varieties one, five, six, seven, or ten. Calculated correlations of the 12 and 24-hour in vitro (artificial rumen) dry matter digestibility and of coefficients estimated by the summative equation were not highly significant. Relationships of chemical constituent data of grass and legume samples from detergent analysis provided evidence that this feed-stuff fractionation accurately reflects differences in chemical composition between species. Hemicellulose values of the grass were four times as great as those of the alfalfa, but the cellulose content was similar for the two forage types. Comparison of silage corn data with that of the alfalfa gave a relationship analogous to that of the alfalfa-grass. Residual ash values of the grass were ten times larger than those of the alfalfa. However, it was not an important factor limiting nutritive value in either the alfalfa or the silage corn. Alfalfa cell wall level and its digestibility were lower than that of the grass. But cell wall material of the grass was twice the amount contained in the alfalfa, and its digestibility was also higher which reflects its lower degree of lignification. Close

• 80. [Article] Combining ability and associations of agronomic traits involving three sources of dwarfism in wheat (Triticum aestivum, L. em Thell)

  Three genetically different dwarf cultivars of spring wheat were evaluated as potential sources of short stature to use in a wheat improvement program. The study involved a five parent diallel cross which ...

  Citation × Citation Citation Abstract Copy Title: Combining ability and associations of agronomic traits involving three sources of dwarfism in wheat (Triticum aestivum, L. em Thell) Author: Maya de Leon, Jose Luis Three genetically different dwarf cultivars of spring wheat were evaluated as potential sources of short stature to use in a wheat improvement program. The study involved a five parent diallel cross which included a semidwarf, a standard height and three dwarf cultivars. The genetic sources of dwarfism included a Norma 10 derivative named Vicam 71, a derived line from Tom Thumb called Tordo, and Olesen dwarf. Experimental material consisted of parental lines, F₁, F₂, and both backcrosses to the parents space planted in a randomized block design. The agronomic characters measured on an individual plant basis were: (1) plant height, (2) days to heading, (3) number of tillers, (4) number of spikelets per spike, (5) head length, (6) days to maturity, (7) grain yield, (8) harvest index, (9) kernel weight, (10) number of kernels per spikelet, (11) rachis internode length, (12) grain filling period and, (13) head grain weight. Estimates of gene action were determined by heterosis, heterobeltiosis, broad and narrow sense heritabilities and combining ability analyses. Associations among traits were estimated by phenotypic, environmental, and genotypic correlations as well as path-coefficient analysis for grain yield and eight of the variables. There were significant differences among the parental lines, their crosses, and generations for all traits measured. Either partial dominance for tallness or no dominance was manifested for those crosses involving the dwarf cultivars Vicam 71 and Olesen. Tordo, when crossed to taller wheats showed dominance for short stature. All three genetic sources of dwarfism and their resulting progenies manifested desirable agronomic characteristics. Vicam 71 was a good parent in terms of grain yield and number of tillers per plant. Tordo was the best source for increasing the number of spikelets per spike, kernel weight and head grain weight. Olesen was a good progenitor for increasing number of kernels per spikelet. All three dwarf cultivars displayed some advantage(s) over the other two and all could be used to breed short statured wheats with a possibility of success. Plant height did not appear to have a direct effect on plant grain yield in any of the 10 crosses. With the exception of number of tillers per plant and grain yield, a major proportion of the phenotypic variability observed for all characters studied was due to genetic factors. A large portion of the total genetic variability associated with days to heading, maturity, height, rachis internode, spikelet number, kernels per spikelet, kernel weight, and harvest index was mainly a result of additive gene action. Both additive and non-additive genetic effects were involved in the expression of grain filling period and head weight. The nonadditive portion of the genetic variance associated with tiller number and grain yield per plant was relatively large when compared with the additive portion. Therefore, selection for increased expression of tillers and yield should be delayed until the F₄ or later generations where a large degree of homozygosity has been obtained. The genetic correlations for individual crosses indicated that only a few of the traits studied were associated in the same manner in most or all the 10 hybridizations. High positive genetic correlations were found between plant grain yield vs tiller number and kernels per spikelet, tiller number vs days to maturity, kernels per spikelet vs head grain weight, plant height vs head weight, and head length vs rachis internode length. High negative genetic correlations were found between kernel weight vs days to maturity, plant height vs harvest index, and days to heading vs grain filling period. Most correlations among agronomic traits were different in value and/or sign from one cross to another suggesting different gene associations in the parental cultivars. Genetic correlations between components of yield showed this type of inconsistency. Therefore, grain yield could be increased by a combined increase of more than one component of yield without compensatory oscillation among them because tiller number, spikelet number, kernels per spikelet and kernel weight were often not correlated between one another and sometimes were positively correlated. Path-coefficients analysis indicated that number of tiller per plant had a high direct effect on grain yield in all crosses. With the exception of two crosses, indirect effects of this trait were negligible. In the latter two crosses tiller number had a high negative indirect effect on plant grain yield via head grain weight. Kernels per spikelet and kernel weight had no direct effects on grain yield but their indirect effects via head weight were positive and significant. Large amounts of additive gene action were observed in the expression of plant height. This trait was also highly negatively correlated with harvest index; therefore, phenotypic selection for restricted plant height would be useful in obtaining lines with high grain to straw ratios. In general, crosses that showed high specific combining ability effects involved parents with low general combining ability. However, there were some exceptions to this rule. Crosses of high x high and high x low general combiners presented high specific combining ability effects, suggesting that some additive gene action may be involved in the superior performance of these combinations. Also the F ₂ generation did not differ from the F₁ in assessing general cornbining ability. A wheat breeder should be aware of those genetic associations between agronomic traits that could be used to select superior cultivars. However, the genetic correlations in this study suggested that each cross represented a different set of gene associations depending upon the parents involved. If some progress is to be made in using the genetic variability available in the crop, the breeder should not try to select exactly the same type of plant from every cross. Every hybridization is potentially a source of better lines if they are well planned and the reasons they were made are remembered during selection. It is very important to realize what are the contributions of each parental line in a cross and what are the most important trait associations present in each parent. Superior rural genetic variability existing in the crop. Title: Combining ability and associations of agronomic traits involving three sources of dwarfism in wheat (Triticum aestivum, L. em Thell) Author: Maya de Leon, Jose Luis Three genetically different dwarf cultivars of spring wheat were evaluated as potential sources of short stature to use in a wheat improvement program. The study involved a five parent diallel cross which included a semidwarf, a standard height and three dwarf cultivars. The genetic sources of dwarfism included a Norma 10 derivative named Vicam 71, a derived line from Tom Thumb called Tordo, and Olesen dwarf. Experimental material consisted of parental lines, F₁, F₂, and both backcrosses to the parents space planted in a randomized block design. The agronomic characters measured on an individual plant basis were: (1) plant height, (2) days to heading, (3) number of tillers, (4) number of spikelets per spike, (5) head length, (6) days to maturity, (7) grain yield, (8) harvest index, (9) kernel weight, (10) number of kernels per spikelet, (11) rachis internode length, (12) grain filling period and, (13) head grain weight. Estimates of gene action were determined by heterosis, heterobeltiosis, broad and narrow sense heritabilities and combining ability analyses. Associations among traits were estimated by phenotypic, environmental, and genotypic correlations as well as path-coefficient analysis for grain yield and eight of the variables. There were significant differences among the parental lines, their crosses, and generations for all traits measured. Either partial dominance for tallness or no dominance was manifested for those crosses involving the dwarf cultivars Vicam 71 and Olesen. Tordo, when crossed to taller wheats showed dominance for short stature. All three genetic sources of dwarfism and their resulting progenies manifested desirable agronomic characteristics. Vicam 71 was a good parent in terms of grain yield and number of tillers per plant. Tordo was the best source for increasing the number of spikelets per spike, kernel weight and head grain weight. Olesen was a good progenitor for increasing number of kernels per spikelet. All three dwarf cultivars displayed some advantage(s) over the other two and all could be used to breed short statured wheats with a possibility of success. Plant height did not appear to have a direct effect on plant grain yield in any of the 10 crosses. With the exception of number of tillers per plant and grain yield, a major proportion of the phenotypic variability observed for all characters studied was due to genetic factors. A large portion of the total genetic variability associated with days to heading, maturity, height, rachis internode, spikelet number, kernels per spikelet, kernel weight, and harvest index was mainly a result of additive gene action. Both additive and non-additive genetic effects were involved in the expression of grain filling period and head weight. The nonadditive portion of the genetic variance associated with tiller number and grain yield per plant was relatively large when compared with the additive portion. Therefore, selection for increased expression of tillers and yield should be delayed until the F₄ or later generations where a large degree of homozygosity has been obtained. The genetic correlations for individual crosses indicated that only a few of the traits studied were associated in the same manner in most or all the 10 hybridizations. High positive genetic correlations were found between plant grain yield vs tiller number and kernels per spikelet, tiller number vs days to maturity, kernels per spikelet vs head grain weight, plant height vs head weight, and head length vs rachis internode length. High negative genetic correlations were found between kernel weight vs days to maturity, plant height vs harvest index, and days to heading vs grain filling period. Most correlations among agronomic traits were different in value and/or sign from one cross to another suggesting different gene associations in the parental cultivars. Genetic correlations between components of yield showed this type of inconsistency. Therefore, grain yield could be increased by a combined increase of more than one component of yield without compensatory oscillation among them because tiller number, spikelet number, kernels per spikelet and kernel weight were often not correlated between one another and sometimes were positively correlated. Path-coefficients analysis indicated that number of tiller per plant had a high direct effect on grain yield in all crosses. With the exception of two crosses, indirect effects of this trait were negligible. In the latter two crosses tiller number had a high negative indirect effect on plant grain yield via head grain weight. Kernels per spikelet and kernel weight had no direct effects on grain yield but their indirect effects via head weight were positive and significant. Large amounts of additive gene action were observed in the expression of plant height. This trait was also highly negatively correlated with harvest index; therefore, phenotypic selection for restricted plant height would be useful in obtaining lines with high grain to straw ratios. In general, crosses that showed high specific combining ability effects involved parents with low general combining ability. However, there were some exceptions to this rule. Crosses of high x high and high x low general combiners presented high specific combining ability effects, suggesting that some additive gene action may be involved in the superior performance of these combinations. Also the F ₂ generation did not differ from the F₁ in assessing general cornbining ability. A wheat breeder should be aware of those genetic associations between agronomic traits that could be used to select superior cultivars. However, the genetic correlations in this study suggested that each cross represented a different set of gene associations depending upon the parents involved. If some progress is to be made in using the genetic variability available in the crop, the breeder should not try to select exactly the same type of plant from every cross. Every hybridization is potentially a source of better lines if they are well planned and the reasons they were made are remembered during selection. It is very important to realize what are the contributions of each parental line in a cross and what are the most important trait associations present in each parent. Superior rural genetic variability existing in the crop. Close