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• 111. [Article] Influence of cover crop residue management on soil moisture, vine growth, and productivity in a pre-production vineyard in the Willamette Valley

  The use of cover crops in young vineyards is not widely accepted in the Pacific Northwest due to concerns of water and nutrient competition between the cover crop and vines. The last 2 years of a 4-year ...

  Citation × Citation Citation Abstract Copy Title: Influence of cover crop residue management on soil moisture, vine growth, and productivity in a pre-production vineyard in the Willamette Valley Author: Curtis, Morgan A. The use of cover crops in young vineyards is not widely accepted in the Pacific Northwest due to concerns of water and nutrient competition between the cover crop and vines. The last 2 years of a 4-year study started in 2009 are reported here. The study evaluated the use of biomass management of a winter annual cover to enhance growth and conserve soil moisture. A winter annual cover crop of cereal rye (Secale cereale) and crimson clover (Trifolium incarnatum) was planted each fall in a pre-production Vitis vinifera 'Chardonnay' vineyard. Cover-cropped treatments were compared to an unplanted treatment which was never planted to cover crop and kept free of vegetation by tillage and/or herbicides for the duration of the study. In spring, cover crop biomass was mowed and residues were placed in the alleys, removed from the alleys, or applied as a mulch to the vine row at two densities (one equal to the alley biomass, and one with triple the alley biomass). All treatments were tilled and kept free of vegetation during the summer. Insufficient residue was produced in 2012 and data collected in that year was used to determine residual effects from three prior years of treatments. Higher levels of soil moisture were maintained in mulched treatments through the summer of 2011. Soil mechanical resistance was decreased under the high level of mulch. Root density was increased in mulched vine rows, likely as a result of both increased soil moisture and reduced soil mechanical resistance. In 2011, shoot growth was increased by 17% in mulch treatments, and fruitfulness was higher in 2011 and 2012. Tissue nitrogen and leaf chlorophyll were increased in mulched treatments at bloom, and potassium and boron were higher with the high level of mulch in 2011. Clusters were larger in the high level of mulch treatment with more berries per cluster, but berry weight and fruit yield were not different. Cover crop and mulch did not alter soluble solids, pH, titratable acidity, or yeast assimilable nitrogen. By using a winter annual cover crop, consisting of a mix of grasses and legumes, and applying the biomass to the vines in the spring, cover crops can be a viable management option for establishing vineyards in the Pacific Northwest. Title: Influence of cover crop residue management on soil moisture, vine growth, and productivity in a pre-production vineyard in the Willamette Valley Author: Curtis, Morgan A. The use of cover crops in young vineyards is not widely accepted in the Pacific Northwest due to concerns of water and nutrient competition between the cover crop and vines. The last 2 years of a 4-year study started in 2009 are reported here. The study evaluated the use of biomass management of a winter annual cover to enhance growth and conserve soil moisture. A winter annual cover crop of cereal rye (Secale cereale) and crimson clover (Trifolium incarnatum) was planted each fall in a pre-production Vitis vinifera 'Chardonnay' vineyard. Cover-cropped treatments were compared to an unplanted treatment which was never planted to cover crop and kept free of vegetation by tillage and/or herbicides for the duration of the study. In spring, cover crop biomass was mowed and residues were placed in the alleys, removed from the alleys, or applied as a mulch to the vine row at two densities (one equal to the alley biomass, and one with triple the alley biomass). All treatments were tilled and kept free of vegetation during the summer. Insufficient residue was produced in 2012 and data collected in that year was used to determine residual effects from three prior years of treatments. Higher levels of soil moisture were maintained in mulched treatments through the summer of 2011. Soil mechanical resistance was decreased under the high level of mulch. Root density was increased in mulched vine rows, likely as a result of both increased soil moisture and reduced soil mechanical resistance. In 2011, shoot growth was increased by 17% in mulch treatments, and fruitfulness was higher in 2011 and 2012. Tissue nitrogen and leaf chlorophyll were increased in mulched treatments at bloom, and potassium and boron were higher with the high level of mulch in 2011. Clusters were larger in the high level of mulch treatment with more berries per cluster, but berry weight and fruit yield were not different. Cover crop and mulch did not alter soluble solids, pH, titratable acidity, or yeast assimilable nitrogen. By using a winter annual cover crop, consisting of a mix of grasses and legumes, and applying the biomass to the vines in the spring, cover crops can be a viable management option for establishing vineyards in the Pacific Northwest. Close

• 112. [Article] Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition

  Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused ...

  Citation × Citation Citation Abstract Copy Title: Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition Author: Topitzhofer, Ellen Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused significant concern and hence have been a topic of intensive investigation. These declines are reportedly due to multiple factors. Poor nutrition, which may be a result of current migratory pollination practices, is one such factor. Migratory pollination is a common practice of beekeepers from the Pacific Northwest and involves the placement of managed honey bee colonies within a series of cropping systems. There is a gap in knowledge on how migratory pollination practices impact honey bee nutrition. To understand the potential impacts of migratory pollination on honey bee nutrition, it is critical to assess the diversity of pollen collected by bees when colonies are placed adjacent to these cropping systems. In this study, we describe the diversity of pollen collected by honey bee colonies managed by beekeepers in the Pacific Northwest region of the United States when placed in seven major cropping systems. We quantified the percent of target crop pollen and overall diversity of pollen collected by honey bees when colonies were placed in these cropping systems. We collected and identified pollen in almond (Prunus dulcis (Mill.)), cherry (Prunus avium L.), highbush blueberry (Vaccinium corymbosum L.), meadowfoam (Limnanthes alba Benth.), white clover (Trifolium repens L.), radish (Raphanus sativus L.), and carrot (Daucus carota (Hoffm.)) cropping systems. We found that pollen collected from colonies placed in almond cropping systems was predominately Prunus sp., and hence, low in pollen diversity. At the other end of the spectrum, pollen collected from colonies placed adjacent to blueberry cropping systems did not yield any target pollen types (Highbush blueberry, Vaccinium corymbosum L.), but was high in overall pollen diversity. The pollen collected from colonies placed in other cropping systems was largely intermediate in diversity between these two extremes. There were not many plant species in bloom when pollen was collected from colonies placed in almond cropping system, whereas more plants were in bloom when we collected pollen from colonies placed in blueberry cropping system. The results of this study demonstrate that honey bees collected pollen from plants in the surrounding environment and collected different degrees of pollen diversity across different cropping systems in which the colonies were placed. We further determined if pollen diversity influences colony-level protein utilization and biosynthesis of protein in nurse bees by conducting a pollen feeding experiment. Pollen collected from four different cropping systems in the first study was used to formulate four different diets, each varying in pollen diversity. We measured protein consumption in experimental colonies and by sampling nurse bees from each colony to estimate hypopharyngeal gland protein content and proteolytic enzyme activity after five weeks of feeding on the experimental pollen diets. Experimental colonies fed on pollen collected from almond cropping system exhibited a high protein consumption rate. However, low protein content as found in hypopharyngeal glands of nurse bees in these colonies. The nurse bees in these colonies also had low proteolytic enzyme activity, which indicates a lower rate of protein digestion. Overall, these results suggest that the diet representing pollen collected from almond cropping systems had low digestion rate and may have resulted in lower nurse bee hypopharyngeal gland protein. However, we cannot say this with certainty, as there were other confounding factors involved, such as presence of pesticides in the pollen collected from the cropping systems. Title: Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition Author: Topitzhofer, Ellen Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused significant concern and hence have been a topic of intensive investigation. These declines are reportedly due to multiple factors. Poor nutrition, which may be a result of current migratory pollination practices, is one such factor. Migratory pollination is a common practice of beekeepers from the Pacific Northwest and involves the placement of managed honey bee colonies within a series of cropping systems. There is a gap in knowledge on how migratory pollination practices impact honey bee nutrition. To understand the potential impacts of migratory pollination on honey bee nutrition, it is critical to assess the diversity of pollen collected by bees when colonies are placed adjacent to these cropping systems. In this study, we describe the diversity of pollen collected by honey bee colonies managed by beekeepers in the Pacific Northwest region of the United States when placed in seven major cropping systems. We quantified the percent of target crop pollen and overall diversity of pollen collected by honey bees when colonies were placed in these cropping systems. We collected and identified pollen in almond (Prunus dulcis (Mill.)), cherry (Prunus avium L.), highbush blueberry (Vaccinium corymbosum L.), meadowfoam (Limnanthes alba Benth.), white clover (Trifolium repens L.), radish (Raphanus sativus L.), and carrot (Daucus carota (Hoffm.)) cropping systems. We found that pollen collected from colonies placed in almond cropping systems was predominately Prunus sp., and hence, low in pollen diversity. At the other end of the spectrum, pollen collected from colonies placed adjacent to blueberry cropping systems did not yield any target pollen types (Highbush blueberry, Vaccinium corymbosum L.), but was high in overall pollen diversity. The pollen collected from colonies placed in other cropping systems was largely intermediate in diversity between these two extremes. There were not many plant species in bloom when pollen was collected from colonies placed in almond cropping system, whereas more plants were in bloom when we collected pollen from colonies placed in blueberry cropping system. The results of this study demonstrate that honey bees collected pollen from plants in the surrounding environment and collected different degrees of pollen diversity across different cropping systems in which the colonies were placed. We further determined if pollen diversity influences colony-level protein utilization and biosynthesis of protein in nurse bees by conducting a pollen feeding experiment. Pollen collected from four different cropping systems in the first study was used to formulate four different diets, each varying in pollen diversity. We measured protein consumption in experimental colonies and by sampling nurse bees from each colony to estimate hypopharyngeal gland protein content and proteolytic enzyme activity after five weeks of feeding on the experimental pollen diets. Experimental colonies fed on pollen collected from almond cropping system exhibited a high protein consumption rate. However, low protein content as found in hypopharyngeal glands of nurse bees in these colonies. The nurse bees in these colonies also had low proteolytic enzyme activity, which indicates a lower rate of protein digestion. Overall, these results suggest that the diet representing pollen collected from almond cropping systems had low digestion rate and may have resulted in lower nurse bee hypopharyngeal gland protein. However, we cannot say this with certainty, as there were other confounding factors involved, such as presence of pesticides in the pollen collected from the cropping systems. Close

• 113. [Article] Low-altitude, high-resolution aerial imaging systems for row and field crop phenotyping: A review

  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 published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Low-altitude, high-resolution aerial imaging systems for row and field crop phenotyping: A review Author: Espinoza, Carlos Zúñiga, Sankaran, Sindhuja, Pumphrey, Michael O., Miklas, Phillip N., Carter, Arron H., Vandemark, George J., Knowles, N. Richard, Khot, Lav R., Jarolmasjed, Sanaz, Sathuvalli, Vidyasagar R., Payek, Mark J. 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 published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/european-journal-of-agronomy/. Title: Low-altitude, high-resolution aerial imaging systems for row and field crop phenotyping: A review Author: Espinoza, Carlos Zúñiga, Sankaran, Sindhuja, Pumphrey, Michael O., Miklas, Phillip N., Carter, Arron H., Vandemark, George J., Knowles, N. Richard, Khot, Lav R., Jarolmasjed, Sanaz, Sathuvalli, Vidyasagar R., Payek, Mark J. 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 published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/european-journal-of-agronomy/. Close

• 114. [Article] Tree and crop productivity and soil organic matter changes as influenced by Leucaena hedge-row management in sub-humid India

  The overall objective of this study was to evaluate biomass production and soil ameliorative potential of alley farming in sub-humid India. Effect of the cutting height (40, 80, 120, 160 cm) of Leucaena ...

  Citation × Citation Citation Abstract Copy Title: Tree and crop productivity and soil organic matter changes as influenced by Leucaena hedge-row management in sub-humid India Author: Singh, Rajive K. The overall objective of this study was to evaluate biomass production and soil ameliorative potential of alley farming in sub-humid India. Effect of the cutting height (40, 80, 120, 160 cm) of Leucaena hedges and root barriers on biomass yield of Leucaena and maize and wheat crops were examined. Trees were pruned at sowing of crops and pruned biomass recycled as surface mulch at the rate of 0, 1.5, 3, 4.5 and 6 Mg ha⁻¹ twice every year. Biomass production from the trees increased with increasing cutting height up to 120 cm without any substantial reduction in the crop yields. Root barriers had little effect on trees, no effect on maize, but significantly increased wheat grain and straw yield near the trees indicating competitive below ground interaction between Leucaena and wheat. Some alteration in pruning timing may help to minimize tree-crop competition. Crop yields sharply increased with increasing mulch levels when compared on a net-cropped-area basis. However, growing of higher levels of mulch material rapidly reduced area under crops. When adjusted for loss in crop area, a reduction in the grain production was estimated with increasing mulch levels. Estimates based on tree-crop interactions observed in this study show that an alley cropping system with 20% area under Leucaena hedge-rows would provide about 12% lower grain yield and 15% higher fodder yield from crops compared to sole cropping system. In addition, trees would provide about 3.2 Mg ha⁻¹ fuel wood. In such an arrangement, about 3 Mg ha⁻¹yr⁻¹ mulch can be recycled which will have little soil ameliorative value as it showed only marginal increase in soil organic matter (SOM). The system should, however, maintain current yield levels. I used a simulation model SCUAF (Soil Changes Under Agro-Forestry) for predicting expected changes in SOM under different mulch levels. The predicted changes in SOM after a period of 25 years were of the same magnitude as observed changes in soil microbial biomass (Bc) during the 3 year study. Results of this study support the hypotheses that the Bc:Oc ratio tends to return to a climate induced equilibria and early changes in Bc may be used for providing quantitative projections of changes in SOM under different land management options. However, this relationship needs to be validated with long-term field data. Title: Tree and crop productivity and soil organic matter changes as influenced by Leucaena hedge-row management in sub-humid India Author: Singh, Rajive K. The overall objective of this study was to evaluate biomass production and soil ameliorative potential of alley farming in sub-humid India. Effect of the cutting height (40, 80, 120, 160 cm) of Leucaena hedges and root barriers on biomass yield of Leucaena and maize and wheat crops were examined. Trees were pruned at sowing of crops and pruned biomass recycled as surface mulch at the rate of 0, 1.5, 3, 4.5 and 6 Mg ha⁻¹ twice every year. Biomass production from the trees increased with increasing cutting height up to 120 cm without any substantial reduction in the crop yields. Root barriers had little effect on trees, no effect on maize, but significantly increased wheat grain and straw yield near the trees indicating competitive below ground interaction between Leucaena and wheat. Some alteration in pruning timing may help to minimize tree-crop competition. Crop yields sharply increased with increasing mulch levels when compared on a net-cropped-area basis. However, growing of higher levels of mulch material rapidly reduced area under crops. When adjusted for loss in crop area, a reduction in the grain production was estimated with increasing mulch levels. Estimates based on tree-crop interactions observed in this study show that an alley cropping system with 20% area under Leucaena hedge-rows would provide about 12% lower grain yield and 15% higher fodder yield from crops compared to sole cropping system. In addition, trees would provide about 3.2 Mg ha⁻¹ fuel wood. In such an arrangement, about 3 Mg ha⁻¹yr⁻¹ mulch can be recycled which will have little soil ameliorative value as it showed only marginal increase in soil organic matter (SOM). The system should, however, maintain current yield levels. I used a simulation model SCUAF (Soil Changes Under Agro-Forestry) for predicting expected changes in SOM under different mulch levels. The predicted changes in SOM after a period of 25 years were of the same magnitude as observed changes in soil microbial biomass (Bc) during the 3 year study. Results of this study support the hypotheses that the Bc:Oc ratio tends to return to a climate induced equilibria and early changes in Bc may be used for providing quantitative projections of changes in SOM under different land management options. However, this relationship needs to be validated with long-term field data. Close

• 115. [Article] Mapping QTL for root rot resistance, root traits, and morphological trait in a common bean recombinant inbred population

  Root rot diseases of bean (Phaseolus vulgaris L.) are a problem wherever they are grown, and are a major constraint to dry edible and snap bean production. Root rot is a primary yield limitation of snap ...

  Citation × Citation Citation Abstract Copy Title: Mapping QTL for root rot resistance, root traits, and morphological trait in a common bean recombinant inbred population Author: Hagerty, Christina H. Root rot diseases of bean (Phaseolus vulgaris L.) are a problem wherever they are grown, and are a major constraint to dry edible and snap bean production. Root rot is a primary yield limitation of snap bean production in the US, especially within the top three snap bean producing states of Wisconsin, Oregon and New York. Bean root rot pathogens will be present by the end of the first season even when starting with clean ground. The decline in yield can be relatively slow, so growers might not notice or appreciate the hidden yield cost associated with root rot disease. Traditional methods for disease control such as fungicides, crop rotations, cover crops, seedbed preparations have been proven ineffective (either physically ineffective or economically unviable) against root rot. Therefore, genetic resistance is needed. In order to address the need for genetic resistance to root rot in snap beans, the highly root rot resistant line RR6950, a small seeded black indeterminate type IIIA accession of unknown origin, was crossed with OSU5446, a highly root rot susceptible determinate type I blue lake four-sieve breeding line to produce the RR138 recombinant inbred mapping population. In this study we evaluated the RR138 RI population in the F₆ generation for resistance to Fusarium solani root rot in Oregon and Aphanomyces euteiches root rot in Wisconsin. We also evaluated this population for morphological traits and root structural traits including pod height, pod width, pod length, pod wall thickness, strings, seed color, flower color, tap and basal root diameter, and root angle measurements. The RR138 population was also genotyped on the 10K BeanCAP Illumina Beadchip. The Single Nucleotide Polymorphism (SNP) data was used to assemble a high-density linkage map and Quantitative Trait Loci (QTL) for phenotypic data were evaluated. The linkage map produced from this study contained 1,689 SNPs across 1,196cM. The map was populated with 1 SNP for every 1.4cM, spanning across 11 linkage groups. Three QTL associated with A. euteiches root rot resistance were consistently expressed in 2011 and 2012 trials. A. euteiches QTL were found on Pv02, Pv04, and Pv06 and accounted for 7-17% of total genetic variation. Two QTL associated with F. solani were found in 2011 trial on Pv03 and Pv07, account for 9 and 22% of total genetic variation, respectively. We also found several QTL for morphological traits and root structural traits including QTL for pod fiber and pod height on Pv04, pod length on Pv01, strings on Pv01, taproot diameter on Pv05, and shallow basal root angle on Pv05, accounting for 21, 26, 12, 20, 11, and 19% of total genetic variation, respectively. QTL discovered from Oregon data for F. solani resistance did not cluster with QTL for A. euteiches root rot resistance. "SNP0928_7", was highly associated with F. solani resistance on Pv07 and "SNP0508_2", was highly associated with A. euteiches on Pv02. QTL and markers associated with QTL from this study will be of value to snap bean breeders developing root rot resistant lines with processing traits, and provide more information about targeting the mechanism of resistance. Title: Mapping QTL for root rot resistance, root traits, and morphological trait in a common bean recombinant inbred population Author: Hagerty, Christina H. Root rot diseases of bean (Phaseolus vulgaris L.) are a problem wherever they are grown, and are a major constraint to dry edible and snap bean production. Root rot is a primary yield limitation of snap bean production in the US, especially within the top three snap bean producing states of Wisconsin, Oregon and New York. Bean root rot pathogens will be present by the end of the first season even when starting with clean ground. The decline in yield can be relatively slow, so growers might not notice or appreciate the hidden yield cost associated with root rot disease. Traditional methods for disease control such as fungicides, crop rotations, cover crops, seedbed preparations have been proven ineffective (either physically ineffective or economically unviable) against root rot. Therefore, genetic resistance is needed. In order to address the need for genetic resistance to root rot in snap beans, the highly root rot resistant line RR6950, a small seeded black indeterminate type IIIA accession of unknown origin, was crossed with OSU5446, a highly root rot susceptible determinate type I blue lake four-sieve breeding line to produce the RR138 recombinant inbred mapping population. In this study we evaluated the RR138 RI population in the F₆ generation for resistance to Fusarium solani root rot in Oregon and Aphanomyces euteiches root rot in Wisconsin. We also evaluated this population for morphological traits and root structural traits including pod height, pod width, pod length, pod wall thickness, strings, seed color, flower color, tap and basal root diameter, and root angle measurements. The RR138 population was also genotyped on the 10K BeanCAP Illumina Beadchip. The Single Nucleotide Polymorphism (SNP) data was used to assemble a high-density linkage map and Quantitative Trait Loci (QTL) for phenotypic data were evaluated. The linkage map produced from this study contained 1,689 SNPs across 1,196cM. The map was populated with 1 SNP for every 1.4cM, spanning across 11 linkage groups. Three QTL associated with A. euteiches root rot resistance were consistently expressed in 2011 and 2012 trials. A. euteiches QTL were found on Pv02, Pv04, and Pv06 and accounted for 7-17% of total genetic variation. Two QTL associated with F. solani were found in 2011 trial on Pv03 and Pv07, account for 9 and 22% of total genetic variation, respectively. We also found several QTL for morphological traits and root structural traits including QTL for pod fiber and pod height on Pv04, pod length on Pv01, strings on Pv01, taproot diameter on Pv05, and shallow basal root angle on Pv05, accounting for 21, 26, 12, 20, 11, and 19% of total genetic variation, respectively. QTL discovered from Oregon data for F. solani resistance did not cluster with QTL for A. euteiches root rot resistance. "SNP0928_7", was highly associated with F. solani resistance on Pv07 and "SNP0508_2", was highly associated with A. euteiches on Pv02. QTL and markers associated with QTL from this study will be of value to snap bean breeders developing root rot resistant lines with processing traits, and provide more information about targeting the mechanism of resistance. Close

• 116. [Article] Handling high moisture seed

  Citation × Citation Citation Abstract Copy Title: Handling high moisture seed Author: Grabe, Don F., Oregon State University. Extension Service, Youngberg, Harold Wayne, 1929- Title: Handling high moisture seed Author: Grabe, Don F., Oregon State University. Extension Service, Youngberg, Harold Wayne, 1929- Close

• 117. [Article] Registration of NM-9D11A-AN3 Anthracnose Resistant Alfalfa Germplasm

  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 published article is copyrighted by the Crop ...

  Citation × Citation Citation Abstract Copy Title: Registration of NM-9D11A-AN3 Anthracnose Resistant Alfalfa Germplasm Author: Ray, I. M., Melton, B. A., Townsend, M. S., Currier, C. G., Henning, J. A. 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 published article is copyrighted by the Crop Science Society of America and can be found at: https://www.crops.org/publications/cs. Title: Registration of NM-9D11A-AN3 Anthracnose Resistant Alfalfa Germplasm Author: Ray, I. M., Melton, B. A., Townsend, M. S., Currier, C. G., Henning, J. A. 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 published article is copyrighted by the Crop Science Society of America and can be found at: https://www.crops.org/publications/cs. Close

• 118. [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

• 119. [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

• 120. [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