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• 111. [Article] Approval seeking motivation : a determinant of conformity to group norms inconsistent with personal values

  This study was designed to assess the effects of approval seeking motivation and social cost upon conformity to group norms which were inconsistent with personal values. Utilizing the Asch conformity paradigm, ...

  Citation × Citation Citation Abstract Copy Title: Approval seeking motivation : a determinant of conformity to group norms inconsistent with personal values Author: Martin, Harry J. This study was designed to assess the effects of approval seeking motivation and social cost upon conformity to group norms which were inconsistent with personal values. Utilizing the Asch conformity paradigm, 321 subjects were exposed to a group opinion which was contradictory to one of their personal values. The results produced several conclusions: (1) approval motivation is an important determinant of conformity with approval motivated individuals yielding to social pressure significantly more than low approval seekers, (2) low approval seekers are value affirming but values tend to have reduced validity as guides for the behavior of high approval seekers, (3) high approval seekers are vulnerable to social cost while low approval seekers are not, (4) awareness of the value in question does not increase resistance to conformity pressures, and (5) significant differences exist in value structures between high and low approval seekers. These findings were integrated into theories of prejudice, social movements, authoritarianism, and existential courage. The results also raised questions as to areas of possible future research. Title: Approval seeking motivation : a determinant of conformity to group norms inconsistent with personal values Author: Martin, Harry J. This study was designed to assess the effects of approval seeking motivation and social cost upon conformity to group norms which were inconsistent with personal values. Utilizing the Asch conformity paradigm, 321 subjects were exposed to a group opinion which was contradictory to one of their personal values. The results produced several conclusions: (1) approval motivation is an important determinant of conformity with approval motivated individuals yielding to social pressure significantly more than low approval seekers, (2) low approval seekers are value affirming but values tend to have reduced validity as guides for the behavior of high approval seekers, (3) high approval seekers are vulnerable to social cost while low approval seekers are not, (4) awareness of the value in question does not increase resistance to conformity pressures, and (5) significant differences exist in value structures between high and low approval seekers. These findings were integrated into theories of prejudice, social movements, authoritarianism, and existential courage. The results also raised questions as to areas of possible future research. Close

• 112. [Article] An evaluation of soil warming for increased crop production

  In regions where soil temperatures limit plant growth, artificial soil warming may be an economically feasible practice. This hypothesis was evaluated in a soil warming experiment near Corvallis, Oregon. This ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of soil warming for increased crop production Author: Rykbost, K. A. In regions where soil temperatures limit plant growth, artificial soil warming may be an economically feasible practice. This hypothesis was evaluated in a soil warming experiment near Corvallis, Oregon. This experiment was prompted by the observation that multiple use of waste heat discharged in the condenser cooling water of thermal power plants may become an important consideration in the development and siting of these plants. The thermal discharge might be used to achieve increased soil temperature by circulating warm water through a subsurface pipe network. Objectives of this investigation were: (1) to determine the effect, if any, of buried line heat sources on air temperatures within a crop canopy; (2) to determine the extent to which soil temperature can be elevated with buried line heat sources maintained at various temperatures; (3) to establish the effect of subsurface heating on soil water regimes and to evaluate a subsurface irrigation system as a means of maintaining high soil water content and hence high rates of heat transfer in the vicinity of heat sources; (4) to evaluate a theoretical model for prediction of energy dissipation rates; (5) to establish the yield response to soil warming for numerous crops; and (6) to evaluate the influence of subsurface heating on soil and air temperatures and crop production in a wood frame, plastic covered greenhouse. Six individually controlled electrical heating cables were used to simulate a buried pipe network. Thirteen different crops were grown on heated and unheated areas during the four years of this study. Air and soil temperatures were monitored at over 200 locations with thermistors. Readings were taken with a computerized digital data acquisition system. Soil water content was monitored with electrical resistance blocks. Energy inputs were measured for each heating cable with kilowatt-hour meters. Air temperatures at four heights above the soil surface over bare soil and in a field corn canopy were not appreciably affected by soil warming. Statistically significant temperature increases due to soil warming were observed but they were too small to be of consequence for crop growth. Soil temperatures in the upper 25 centimeters were more responsive to solar heating than to subsurface heating. Temperature increases due to soil warming were one to five degrees centigrade at the five centimeter depth, depending on heat source temperature, time of year, time of day and crop canopy conditions. A major portion of the root zone was maintained above 20 degrees centigrade during most of the growing season. The greatest temperature increases were observed on a plot where subsurface irrigation was used to maintain high soil water content near the heat sources. During the summer substantial soil drying occurred in the vicinity of the heat sources, particularly under a field corn crop. Thermal gradients prevented rewetting by sprinkler irrigation. A subsurface irrigation system maintained a wet soil near the heat sources throughout the growing season. The rate of heat loss from buried heat sources was found to respond to changes in depth and spacing of sources, source temperature, soil surface temperature and soil water content, as predicted by theoretical considerations. A high correlation between mean monthly air temperature and mean monthly heat loss rates was found. The results indicate that the area required to reduce the temperature of circulating warm water, from a 1,000 megawatt thermal power plant, by 10 degrees centigrade would range from 10,000 hectares in the winter to 20,000 hectares in the summer under Willamette Valley climatic conditions. This requirement could be reduced by design modifications or subsurface irrigation. A wide range in crop response to soil warming was observed for different crops and for some crops in different years. The results obtained with field corn and bush beans suggest that the response to soil heating depends on the degree of adversity to which the crop is subjected. When climatic conditions and management factors are optimum soil heating has a limited effect on crop yields. When one or more of these factors are limiting soil heating becomes more effective and greater yield responses occur. In nearly all cases soil warming resulted in more rapid germination and early growth, and earlier maturation. Double cropping of bush beans and double cropping with summer and winter annual forage crops appear to be feasible with soil warming. Yield increases due to soil warming were above 50 percent for several forage and vegetable crops. Several cropping sequences were suggested. Additional input from agricultural economists and engineers is needed to determine those crop combinations which will result in the greatest economic returns from a soil warming system. Soil heating did not result in higher air temperatures in a plastic covered greenhouse. Soil temperatures were substantially increased and this resulted in an increase in tomato production of 64 percent compared with a crop grown in the greenhouse with no soil warming. Strawberry yields did not respond to soil warming in greenhouse culture and this was attributed to high air temperatures due to solar heat trapping during daylight hours. The results of this investigation suggest that soil warming with condenser cooling waters from thermal power plants is feasible. Additional information is needed to evaluate the economic and engineering aspects of a soil warming system. It is unlikely that a soil warming system can fulfill all the needs of a thermal power plant cooling system. Additional studies to evaluate other beneficial uses of waste heat to be used in combination with a soil warming system will be required. Title: An evaluation of soil warming for increased crop production Author: Rykbost, K. A. In regions where soil temperatures limit plant growth, artificial soil warming may be an economically feasible practice. This hypothesis was evaluated in a soil warming experiment near Corvallis, Oregon. This experiment was prompted by the observation that multiple use of waste heat discharged in the condenser cooling water of thermal power plants may become an important consideration in the development and siting of these plants. The thermal discharge might be used to achieve increased soil temperature by circulating warm water through a subsurface pipe network. Objectives of this investigation were: (1) to determine the effect, if any, of buried line heat sources on air temperatures within a crop canopy; (2) to determine the extent to which soil temperature can be elevated with buried line heat sources maintained at various temperatures; (3) to establish the effect of subsurface heating on soil water regimes and to evaluate a subsurface irrigation system as a means of maintaining high soil water content and hence high rates of heat transfer in the vicinity of heat sources; (4) to evaluate a theoretical model for prediction of energy dissipation rates; (5) to establish the yield response to soil warming for numerous crops; and (6) to evaluate the influence of subsurface heating on soil and air temperatures and crop production in a wood frame, plastic covered greenhouse. Six individually controlled electrical heating cables were used to simulate a buried pipe network. Thirteen different crops were grown on heated and unheated areas during the four years of this study. Air and soil temperatures were monitored at over 200 locations with thermistors. Readings were taken with a computerized digital data acquisition system. Soil water content was monitored with electrical resistance blocks. Energy inputs were measured for each heating cable with kilowatt-hour meters. Air temperatures at four heights above the soil surface over bare soil and in a field corn canopy were not appreciably affected by soil warming. Statistically significant temperature increases due to soil warming were observed but they were too small to be of consequence for crop growth. Soil temperatures in the upper 25 centimeters were more responsive to solar heating than to subsurface heating. Temperature increases due to soil warming were one to five degrees centigrade at the five centimeter depth, depending on heat source temperature, time of year, time of day and crop canopy conditions. A major portion of the root zone was maintained above 20 degrees centigrade during most of the growing season. The greatest temperature increases were observed on a plot where subsurface irrigation was used to maintain high soil water content near the heat sources. During the summer substantial soil drying occurred in the vicinity of the heat sources, particularly under a field corn crop. Thermal gradients prevented rewetting by sprinkler irrigation. A subsurface irrigation system maintained a wet soil near the heat sources throughout the growing season. The rate of heat loss from buried heat sources was found to respond to changes in depth and spacing of sources, source temperature, soil surface temperature and soil water content, as predicted by theoretical considerations. A high correlation between mean monthly air temperature and mean monthly heat loss rates was found. The results indicate that the area required to reduce the temperature of circulating warm water, from a 1,000 megawatt thermal power plant, by 10 degrees centigrade would range from 10,000 hectares in the winter to 20,000 hectares in the summer under Willamette Valley climatic conditions. This requirement could be reduced by design modifications or subsurface irrigation. A wide range in crop response to soil warming was observed for different crops and for some crops in different years. The results obtained with field corn and bush beans suggest that the response to soil heating depends on the degree of adversity to which the crop is subjected. When climatic conditions and management factors are optimum soil heating has a limited effect on crop yields. When one or more of these factors are limiting soil heating becomes more effective and greater yield responses occur. In nearly all cases soil warming resulted in more rapid germination and early growth, and earlier maturation. Double cropping of bush beans and double cropping with summer and winter annual forage crops appear to be feasible with soil warming. Yield increases due to soil warming were above 50 percent for several forage and vegetable crops. Several cropping sequences were suggested. Additional input from agricultural economists and engineers is needed to determine those crop combinations which will result in the greatest economic returns from a soil warming system. Soil heating did not result in higher air temperatures in a plastic covered greenhouse. Soil temperatures were substantially increased and this resulted in an increase in tomato production of 64 percent compared with a crop grown in the greenhouse with no soil warming. Strawberry yields did not respond to soil warming in greenhouse culture and this was attributed to high air temperatures due to solar heat trapping during daylight hours. The results of this investigation suggest that soil warming with condenser cooling waters from thermal power plants is feasible. Additional information is needed to evaluate the economic and engineering aspects of a soil warming system. It is unlikely that a soil warming system can fulfill all the needs of a thermal power plant cooling system. Additional studies to evaluate other beneficial uses of waste heat to be used in combination with a soil warming system will be required. Close

• 113. [Article] Local Crop Planting Systems Enhance Insecticide-Mediated Displacement of Two Invasive Leafminer Fly

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Local Crop Planting Systems Enhance Insecticide-Mediated Displacement of Two Invasive Leafminer Fly Author: Zhang, Zhi, Yu, Wenyan, Gao, Yulin, Wei, Qingbo, Reitz, Stuart R., Lei, Zhongren This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Title: Local Crop Planting Systems Enhance Insecticide-Mediated Displacement of Two Invasive Leafminer Fly Author: Zhang, Zhi, Yu, Wenyan, Gao, Yulin, Wei, Qingbo, Reitz, Stuart R., Lei, Zhongren This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Close

• 114. [Article] Constraints and financial profitability to the exploitation of natural

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Constraints and financial profitability to the exploitation of natural Author: Meke Soung, Pierre Nolasque Research Paper Title: Constraints and financial profitability to the exploitation of natural Author: Meke Soung, Pierre Nolasque Research Paper Close

• 115. [Article] Protocol: transient expression system for functional genomics in the tropical tree Theobroma cacao L.

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by BioMed Central. The published article can be found at: http://plantmethods.biomedcentral.com/

  Citation × Citation Citation Abstract Copy Title: Protocol: transient expression system for functional genomics in the tropical tree Theobroma cacao L. Author: Zhang, Yufan, Guiltinan, Mark J., Fister, Andrew S., Shi, Zi, Helliwell, Emily E., Maximova, Siela N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by BioMed Central. The published article can be found at: http://plantmethods.biomedcentral.com/ Title: Protocol: transient expression system for functional genomics in the tropical tree Theobroma cacao L. Author: Zhang, Yufan, Guiltinan, Mark J., Fister, Andrew S., Shi, Zi, Helliwell, Emily E., Maximova, Siela N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by BioMed Central. The published article can be found at: http://plantmethods.biomedcentral.com/ Close

• 116. [Article] Variation in Broccoli Cultivar Phytochemical Content under Organic and Conventional Management Systems: Implications in Breeding for Nutrition

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Variation in Broccoli Cultivar Phytochemical Content under Organic and Conventional Management Systems: Implications in Breeding for Nutrition Author: van Bueren, Edith T. Lammerts, Renaud, Erica N. C., et al., Myers, James R. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Title: Variation in Broccoli Cultivar Phytochemical Content under Organic and Conventional Management Systems: Implications in Breeding for Nutrition Author: van Bueren, Edith T. Lammerts, Renaud, Erica N. C., et al., Myers, James R. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Close

• 117. [Article] Osmotic stress vigor test for wheat seed

  Seed vigor tests have been developed to evaluate the relative ability of seed lots to produce stands of seedlings in the field. Some workers have suggested the possibility of differentiating vigor levels ...

  Citation × Citation Citation Abstract Copy Title: Osmotic stress vigor test for wheat seed Author: Currans, Sean Seed vigor tests have been developed to evaluate the relative ability of seed lots to produce stands of seedlings in the field. Some workers have suggested the possibility of differentiating vigor levels by germinating seeds under osmotic stress, but have not conducted field trials to evaluate the usefulness of the test. This study was conducted to 1) develop an osmotic stress vigor test for wheat seed, 2) evaluate the effectiveness of this test in ranking seed lots for field emergence, and 3) compare the osmotic stress vigor test with other vigor tests. The effects of osmotic potential and temperature on germination of wheat seeds of different vigor levels were investigated. The conditions resulting in greatest differentiation of vigor levels were selected for an osmotic stress vigor test. The osmotic stress test and six other germination and vigor tests were compared for effectiveness in predicting seedling emergence in three field trials of 16 artificially aged and 19 naturally aged seed lots. Reduced osmotic potentials lowered the germination rate of low vigor seeds more than high vigor seeds, but total germination remained the same. The conditions selected for the osmotic stress vigor test were a sand substrate with 50 mL PEG 8000 solution at - 0.5 MPa, with a 10-day germination period in the dark at 20° C. Under adverse field conditions, the osmotic stress test was significantly correlated with field emergence of artificially aged (r = .85) and naturally aged seeds (r = .62). However, the predictive value of the osmotic stress test was lower than some of the other vigor tests, especially accelerated aging and the 4-day sand test. The vigor test rankings varied somewhat under more favorable field conditions. These results indicate the necessity of including several vigor tests and field planting dates when evaluating a specific vigor test. Research should continue to determine the potential of the osmotic stress test and four-day sand tests for application to other seed kinds. Title: Osmotic stress vigor test for wheat seed Author: Currans, Sean Seed vigor tests have been developed to evaluate the relative ability of seed lots to produce stands of seedlings in the field. Some workers have suggested the possibility of differentiating vigor levels by germinating seeds under osmotic stress, but have not conducted field trials to evaluate the usefulness of the test. This study was conducted to 1) develop an osmotic stress vigor test for wheat seed, 2) evaluate the effectiveness of this test in ranking seed lots for field emergence, and 3) compare the osmotic stress vigor test with other vigor tests. The effects of osmotic potential and temperature on germination of wheat seeds of different vigor levels were investigated. The conditions resulting in greatest differentiation of vigor levels were selected for an osmotic stress vigor test. The osmotic stress test and six other germination and vigor tests were compared for effectiveness in predicting seedling emergence in three field trials of 16 artificially aged and 19 naturally aged seed lots. Reduced osmotic potentials lowered the germination rate of low vigor seeds more than high vigor seeds, but total germination remained the same. The conditions selected for the osmotic stress vigor test were a sand substrate with 50 mL PEG 8000 solution at - 0.5 MPa, with a 10-day germination period in the dark at 20° C. Under adverse field conditions, the osmotic stress test was significantly correlated with field emergence of artificially aged (r = .85) and naturally aged seeds (r = .62). However, the predictive value of the osmotic stress test was lower than some of the other vigor tests, especially accelerated aging and the 4-day sand test. The vigor test rankings varied somewhat under more favorable field conditions. These results indicate the necessity of including several vigor tests and field planting dates when evaluating a specific vigor test. Research should continue to determine the potential of the osmotic stress test and four-day sand tests for application to other seed kinds. Close

• 118. [Article] Utilization of surplus Italian prunes

  Prune growers of Oregon are faced with the prospect of large crops and surpluses for the next few years. These surpluses will probably be felt in both fresh and dried prunes. This thesis presents the results ...

  Citation × Citation Citation Abstract Copy Title: Utilization of surplus Italian prunes Author: Fenner, Keith Peck, 1914- Prune growers of Oregon are faced with the prospect of large crops and surpluses for the next few years. These surpluses will probably be felt in both fresh and dried prunes. This thesis presents the results of an investigation to find. new markets and new products which will be of value in utilizing these surpluses. The following products have been investigated and are included in this report. Canned prepared dried prunes. A. prolonged study was made of the effect of prepared Italian prunes on various types of cans. It was found that plain charcoal cans were entirely satisfactory over a period of 11 months' storage. Single enameled cans should not be used as they swell in less than eight months' storage. Methods of preparation of prunes for canning were studied. A long pre-soaking was found most satisfactory, for high quality. Short hot blanch before canning can be used if proper conditions of syrup and fill are observed. Yields and costs were given for the two methods of preparation. Prune beverages. Three types of prune beverages were discussed. Pulpy juice was most promising. A cloudy and a clear beverage were also satisfactory. Yields and costs were given and compared. Pitted prune pulp. Small or low-grade dried prunes were made into pulp by means of a suitable machine. This product was suitable for use in the bakery trade. Halved Pitted prunes. Fresh prunes were split and pitted before drying. The machine to do this was developed during this investigation. Large savings were effected in drying time, because of quicker evaporation of moisture from these halved prunes. Because of shorter drying time and lower temperature the quality was more nearly that of fresh prunes. Fresh Prune Juice. Small or low-grade fresh prunes were used to make a pulpy fresh prune juice. This product was excellent in flavor and color. Cloudy fresh prune juice was not satisfactory either in flavor, in body, or in yield. Fresh Prune Pulp. This was prepared from fresh prunes. It proved to be a very good means of fresh prune utilization. The combined effect of the products studied in this report, if they are developed and marketed, should prove beneficial to marketing conditions of the northwest Italian prunes. Title: Utilization of surplus Italian prunes Author: Fenner, Keith Peck, 1914- Prune growers of Oregon are faced with the prospect of large crops and surpluses for the next few years. These surpluses will probably be felt in both fresh and dried prunes. This thesis presents the results of an investigation to find. new markets and new products which will be of value in utilizing these surpluses. The following products have been investigated and are included in this report. Canned prepared dried prunes. A. prolonged study was made of the effect of prepared Italian prunes on various types of cans. It was found that plain charcoal cans were entirely satisfactory over a period of 11 months' storage. Single enameled cans should not be used as they swell in less than eight months' storage. Methods of preparation of prunes for canning were studied. A long pre-soaking was found most satisfactory, for high quality. Short hot blanch before canning can be used if proper conditions of syrup and fill are observed. Yields and costs were given for the two methods of preparation. Prune beverages. Three types of prune beverages were discussed. Pulpy juice was most promising. A cloudy and a clear beverage were also satisfactory. Yields and costs were given and compared. Pitted prune pulp. Small or low-grade dried prunes were made into pulp by means of a suitable machine. This product was suitable for use in the bakery trade. Halved Pitted prunes. Fresh prunes were split and pitted before drying. The machine to do this was developed during this investigation. Large savings were effected in drying time, because of quicker evaporation of moisture from these halved prunes. Because of shorter drying time and lower temperature the quality was more nearly that of fresh prunes. Fresh Prune Juice. Small or low-grade fresh prunes were used to make a pulpy fresh prune juice. This product was excellent in flavor and color. Cloudy fresh prune juice was not satisfactory either in flavor, in body, or in yield. Fresh Prune Pulp. This was prepared from fresh prunes. It proved to be a very good means of fresh prune utilization. The combined effect of the products studied in this report, if they are developed and marketed, should prove beneficial to marketing conditions of the northwest Italian prunes. Close

• 119. [Article] Evaluation of three methods of selection in relation to yield and yield stability in winter wheat (Triticum aestivum Vill., Host)

  The effectiveness of early generation selection for yield and yield stability and the possible identification of superior parental combinations were studied in winter wheat populations representing different ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of three methods of selection in relation to yield and yield stability in winter wheat (Triticum aestivum Vill., Host) Author: Charoenwatana, Terd, 1937- The effectiveness of early generation selection for yield and yield stability and the possible identification of superior parental combinations were studied in winter wheat populations representing different levels of genetic diversity. Experimental material for evaluating yield stability consisted of nine bulk and seven modified bulk populations derived from nine parental combinations which represented the F₈, F₉, and F₁₀ generations. The F₉ and F₁₀ generations of nine bulk, nine modified bulk and two modified pedigree populations along with the respective parental populations were studied to determine the relationship of yield to genetic diversity. Linear regression of the mean yield of individual entries on the mean yield of all entries for each year was used to describe yield stability. Grain yield differences among populations and crosses were analyzed by a functional analysis of variance. The modified bulk populations were found to be superior to their respective parents in yield and to the bulk populations in yield and yield stability. The modified pedigree populations had the highest yield of all populations measured. It was concluded that populations with high genetic diversity not only do not produce the highest yield but may not provide the greatest stability of yield. Selection for grain yield in the F₄ generation was effective in identifying superior segregates. It was also possible to develop populations which had more yield stability. The highest yielding progeny were obtained from crosses between the medium yielding parents rather than between the highest yielding parents. This suggested that parental performance was of limited value in predicting the yielding ability of their resulting progeny. Therefore, selection for suitable parental combinations could not be based on their individual performance in the present study. It appeared that genetic factors for adaptability are as important as the level of genetic diversity in determining yield stability. A breeding system that allows the breeder to identify and incorporate genetic factors for adaptability and still maintain some genetic diversity in a new variety is suggested. Such a breeding system would prolong the length of time a variety could remain in commercial production and would allow such a variety to be grown over a more extensive range of environments. Title: Evaluation of three methods of selection in relation to yield and yield stability in winter wheat (Triticum aestivum Vill., Host) Author: Charoenwatana, Terd, 1937- The effectiveness of early generation selection for yield and yield stability and the possible identification of superior parental combinations were studied in winter wheat populations representing different levels of genetic diversity. Experimental material for evaluating yield stability consisted of nine bulk and seven modified bulk populations derived from nine parental combinations which represented the F₈, F₉, and F₁₀ generations. The F₉ and F₁₀ generations of nine bulk, nine modified bulk and two modified pedigree populations along with the respective parental populations were studied to determine the relationship of yield to genetic diversity. Linear regression of the mean yield of individual entries on the mean yield of all entries for each year was used to describe yield stability. Grain yield differences among populations and crosses were analyzed by a functional analysis of variance. The modified bulk populations were found to be superior to their respective parents in yield and to the bulk populations in yield and yield stability. The modified pedigree populations had the highest yield of all populations measured. It was concluded that populations with high genetic diversity not only do not produce the highest yield but may not provide the greatest stability of yield. Selection for grain yield in the F₄ generation was effective in identifying superior segregates. It was also possible to develop populations which had more yield stability. The highest yielding progeny were obtained from crosses between the medium yielding parents rather than between the highest yielding parents. This suggested that parental performance was of limited value in predicting the yielding ability of their resulting progeny. Therefore, selection for suitable parental combinations could not be based on their individual performance in the present study. It appeared that genetic factors for adaptability are as important as the level of genetic diversity in determining yield stability. A breeding system that allows the breeder to identify and incorporate genetic factors for adaptability and still maintain some genetic diversity in a new variety is suggested. Such a breeding system would prolong the length of time a variety could remain in commercial production and would allow such a variety to be grown over a more extensive range of environments. Close

• 120. [Article] Impact of artificial flooding on farm profits and streamflow in Echo Meadows, Oregon

  Competition for water both from within the irrigation community and from outside interests has been a major source of conflict in the West. In the Umatilla Basin of central Oregon, Umatilla River water ...

  Citation × Citation Citation Abstract Copy Title: Impact of artificial flooding on farm profits and streamflow in Echo Meadows, Oregon Author: Seely, Harold E Competition for water both from within the irrigation community and from outside interests has been a major source of conflict in the West. In the Umatilla Basin of central Oregon, Umatilla River water is diverted to irrigate a variety of crops, while instream flows have value in salmonid production. Historically, the Umatilla Basin supported runs of fall and spring Chinook as well as steelhead and resident trout but native fish populations have largely disappeared from the river system. The decline in salmonid production has been blamed, in part, on a combination of low streamflow and high water temperatures in the summer months resulting from diversions by agricultural users. This thesis examines a proposed project designed to increase streamflow in the lower Umatilla River during the summer months by artificially flooding selected agricultural land in the Echo Meadows area of the basin during the late winter. The thesis also examines alternative options to increase streamflow. Estimates of the economic and hydrologic impacts of winter water spreading and other options provides information to policy-makers and irrigators on the costs and benefits associated with various project management alternatives. Using information on agricultural production and water supply in the lower Umatilla Basin, this thesis constructs a mathematical optimization model of representative farms in the area. In addition, because return flows represent an important component of streamflow in summer months, water applications determined by the representative farm models are used to assess the impacts of the artificial flooding project on streamflow in the Umatilla River below the study area. The results of the representative farm models indicate that the artificial flooding project increases farm profits by $37,620 and streamflow by 18.58 cubic feet per second. Alternative techniques to obtain similar increases in streamflow are more costly and would have negative effects on the agricultural community. Title: Impact of artificial flooding on farm profits and streamflow in Echo Meadows, Oregon Author: Seely, Harold E Competition for water both from within the irrigation community and from outside interests has been a major source of conflict in the West. In the Umatilla Basin of central Oregon, Umatilla River water is diverted to irrigate a variety of crops, while instream flows have value in salmonid production. Historically, the Umatilla Basin supported runs of fall and spring Chinook as well as steelhead and resident trout but native fish populations have largely disappeared from the river system. The decline in salmonid production has been blamed, in part, on a combination of low streamflow and high water temperatures in the summer months resulting from diversions by agricultural users. This thesis examines a proposed project designed to increase streamflow in the lower Umatilla River during the summer months by artificially flooding selected agricultural land in the Echo Meadows area of the basin during the late winter. The thesis also examines alternative options to increase streamflow. Estimates of the economic and hydrologic impacts of winter water spreading and other options provides information to policy-makers and irrigators on the costs and benefits associated with various project management alternatives. Using information on agricultural production and water supply in the lower Umatilla Basin, this thesis constructs a mathematical optimization model of representative farms in the area. In addition, because return flows represent an important component of streamflow in summer months, water applications determined by the representative farm models are used to assess the impacts of the artificial flooding project on streamflow in the Umatilla River below the study area. The results of the representative farm models indicate that the artificial flooding project increases farm profits by $37,620 and streamflow by 18.58 cubic feet per second. Alternative techniques to obtain similar increases in streamflow are more costly and would have negative effects on the agricultural community. Close