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• 41. [Article] Influential Factors of Parental Substance and Alcohol Abuse on Children’s Academic Achievement

  There is much research to support the idea that parental involvement benefits a child's educational performance. There is also strong evidence demonstrating that parental substance or alcohol abuse increases ...

  Citation × Citation Citation Abstract Copy Title: Influential Factors of Parental Substance and Alcohol Abuse on Children’s Academic Achievement Author: Winters, Andrea Year: 2013 There is much research to support the idea that parental involvement benefits a child's educational performance. There is also strong evidence demonstrating that parental substance or alcohol abuse increases a child's risk for behavioral problems that include drug and alcohol abuse, social-skill deficits, and low educational attainment. Very little current research has focused specifically on children of substance abusers who, against the odds, achieve academically. This study investigates the relationship between parental substance or alcohol abuse and children’s academic achievement. Data will be collected using a self-report survey from adult-children who self-identify as being a child of a past or present substance or alcohol abuser. This study hopes to identify strategies that were used by the subjects to surmount family dysfunction and which helped them to achieve academically. It is expected that these strategies could be used as interventions to help other students by encouraging their academic progress and achievement even amid dysfunctional, substance abusing family situations. Positive psychological theory and resilience theory concepts are used as a backdrop. Substance abuse, specifically alcohol abuse, is the most prevalent psychiatric disorder in the United States, with an estimate in 1992 of 14 million adults who abused or were dependent upon alcohol. The problems of drug and alcohol addiction are worthy of attention as they create concomitant social, economic, and psychological consequences for everyone involved. For example, the collective effects of tobacco, alcohol, and drugs exact greater consequences on the welfare of the American people than any other single preventable factor. The total costs ascribable to addiction are approximated at more than $400 billion every year, including health care costs, low worker productivity, and crime. Faculty Mentor: Valerie Stewart Title: Influential Factors of Parental Substance and Alcohol Abuse on Children’s Academic Achievement Author: Winters, Andrea Year: 2013 There is much research to support the idea that parental involvement benefits a child's educational performance. There is also strong evidence demonstrating that parental substance or alcohol abuse increases a child's risk for behavioral problems that include drug and alcohol abuse, social-skill deficits, and low educational attainment. Very little current research has focused specifically on children of substance abusers who, against the odds, achieve academically. This study investigates the relationship between parental substance or alcohol abuse and children’s academic achievement. Data will be collected using a self-report survey from adult-children who self-identify as being a child of a past or present substance or alcohol abuser. This study hopes to identify strategies that were used by the subjects to surmount family dysfunction and which helped them to achieve academically. It is expected that these strategies could be used as interventions to help other students by encouraging their academic progress and achievement even amid dysfunctional, substance abusing family situations. Positive psychological theory and resilience theory concepts are used as a backdrop. Substance abuse, specifically alcohol abuse, is the most prevalent psychiatric disorder in the United States, with an estimate in 1992 of 14 million adults who abused or were dependent upon alcohol. The problems of drug and alcohol addiction are worthy of attention as they create concomitant social, economic, and psychological consequences for everyone involved. For example, the collective effects of tobacco, alcohol, and drugs exact greater consequences on the welfare of the American people than any other single preventable factor. The total costs ascribable to addiction are approximated at more than $400 billion every year, including health care costs, low worker productivity, and crime. Faculty Mentor: Valerie Stewart Close

• 42. [Article] Relations between Parental Marital Status, Residential Mobility, and Children’s Academic Achievement and Self-Regulation in Kindergarten

  Children’s self-regulation and academic achievement are important factors in predicting school readiness and later academic outcomes. This study examined relationships between parental marital status and ...

  Citation × Citation Citation Abstract Copy Title: Relations between Parental Marital Status, Residential Mobility, and Children’s Academic Achievement and Self-Regulation in Kindergarten Author: Tracy, Alexis, Bukres, Aya, McClelland, Megan M. Children’s self-regulation and academic achievement are important factors in predicting school readiness and later academic outcomes. This study examined relationships between parental marital status and residential mobility on children’s academic achievement and self-regulation in kindergarten. Using a diverse sample of 131 kindergarten children, results indicated that the number of family moves was related to lower literacy skills at the beginning of kindergarten In addition, being a single parent was significantly related to lower self-regulation in children. Title: Relations between Parental Marital Status, Residential Mobility, and Children’s Academic Achievement and Self-Regulation in Kindergarten Author: Tracy, Alexis, Bukres, Aya, McClelland, Megan M. Children’s self-regulation and academic achievement are important factors in predicting school readiness and later academic outcomes. This study examined relationships between parental marital status and residential mobility on children’s academic achievement and self-regulation in kindergarten. Using a diverse sample of 131 kindergarten children, results indicated that the number of family moves was related to lower literacy skills at the beginning of kindergarten In addition, being a single parent was significantly related to lower self-regulation in children. Close

• 43. [Article] Nicoya Peninsula, Costa Rica: A single suite of Caribbean oceanic plateau magmas

  The pre-Tertiary oceanic crust exposed on the west coast of Costa Pica has been broadly referred to as the Nicoya Complex. This study was designed to determine the age of the Nicoya Complex in the Nicoya ...

  Citation × Citation Citation Abstract Copy Title: Nicoya Peninsula, Costa Rica: A single suite of Caribbean oceanic plateau magmas Author: Denyer, Percy, Duncan, Robert A., Sinton, Christopher W. The pre-Tertiary oceanic crust exposed on the west coast of Costa Pica has been broadly referred to as the Nicoya Complex. This study was designed to determine the age of the Nicoya Complex in the Nicoya Peninsula, Playa Jaco, and the Quepos Peninsula using Ar-40-Ar-39 radiometric dating and to assess the petrologic relationships between the different localities using major element, trace element, and Sr, Nd, Pb isotopic data. Radiometric ages of basalts and diabases from the Nicoya Peninsula are 88-90 Ma (with a weighted mean of 88.5 Ma), and those of two intrusive rocks (a gabbro and plagiogranite) are both 83-84 Ma. The combined geochemical data indicate that the sampled Nicoya Peninsula rocks belong to a single suite related by fractional crystallization of similar parental magmas. Nd and Pb isotopic ratios indicate a common mantle source distinct from that of mid-ocean ridge basalts. Both the age and composition of the Nicoya rocks are consistent with the idea that they are a part of the Caribbean Cretaceous oceanic plateau [Donnelly, 1994]. The Jacó lavas are geochemically similar to the Nicoya Peninsula suite, and a single age of 84 Ma is identical to the age of the Nicoya Peninsula intrusives. The one analyzed Quepos basalt has a radiometric age of ~64 Ma, and it is enriched in incompatible elements relative to the Nicoya rocks, Similarities in Nd and Pb isotopic ratios indicate that the Quepos and Nicoya/Jacó lavas were derived from a similar mantle source to that which produced the Nicoya rocks, possibly the Galapagos plume. Title: Nicoya Peninsula, Costa Rica: A single suite of Caribbean oceanic plateau magmas Author: Denyer, Percy, Duncan, Robert A., Sinton, Christopher W. The pre-Tertiary oceanic crust exposed on the west coast of Costa Pica has been broadly referred to as the Nicoya Complex. This study was designed to determine the age of the Nicoya Complex in the Nicoya Peninsula, Playa Jaco, and the Quepos Peninsula using Ar-40-Ar-39 radiometric dating and to assess the petrologic relationships between the different localities using major element, trace element, and Sr, Nd, Pb isotopic data. Radiometric ages of basalts and diabases from the Nicoya Peninsula are 88-90 Ma (with a weighted mean of 88.5 Ma), and those of two intrusive rocks (a gabbro and plagiogranite) are both 83-84 Ma. The combined geochemical data indicate that the sampled Nicoya Peninsula rocks belong to a single suite related by fractional crystallization of similar parental magmas. Nd and Pb isotopic ratios indicate a common mantle source distinct from that of mid-ocean ridge basalts. Both the age and composition of the Nicoya rocks are consistent with the idea that they are a part of the Caribbean Cretaceous oceanic plateau [Donnelly, 1994]. The Jacó lavas are geochemically similar to the Nicoya Peninsula suite, and a single age of 84 Ma is identical to the age of the Nicoya Peninsula intrusives. The one analyzed Quepos basalt has a radiometric age of ~64 Ma, and it is enriched in incompatible elements relative to the Nicoya rocks, Similarities in Nd and Pb isotopic ratios indicate that the Quepos and Nicoya/Jacó lavas were derived from a similar mantle source to that which produced the Nicoya rocks, possibly the Galapagos plume. Close

• 44. [Article] Effective Single-Parent Training Group Program: Three System Studies

  Objective: This study highlights Dr. Elsie Pinkston and colleagues’ research on the effectiveness of behavior parent training and examines the application of single-parent training group (SPG) programs ...

  Citation × Citation Citation Abstract Copy Title: Effective Single-Parent Training Group Program: Three System Studies Author: Briggs, Harold E., Miller, Keva M., Orellana, Edwin Roberto, Briggs, Adam C., Cox, Wendell H. Year: 2013 Objective: This study highlights Dr. Elsie Pinkston and colleagues’ research on the effectiveness of behavior parent training and examines the application of single-parent training group (SPG) programs to three parent–child dyads exposed to distressed family circumstances. Methods: Single-system evaluation designs were conducted with two single birth parents, one single foster parent, and each parent’s three respective children, in an effort to appraise the results of a SPG program. Results: Two of the three parent–child dyads benefited from the SPG. Results suggested that there were changes in parent reinforcement and attention behaviors and children’s noncompliance behaviors. Conclusion: Behavioral improvements in single parent and child dyads lend support for the effectiveness of the parent training group for single parents. Implications for practice and future research on SPG programs are discussed. Title: Effective Single-Parent Training Group Program: Three System Studies Author: Briggs, Harold E., Miller, Keva M., Orellana, Edwin Roberto, Briggs, Adam C., Cox, Wendell H. Year: 2013 Objective: This study highlights Dr. Elsie Pinkston and colleagues’ research on the effectiveness of behavior parent training and examines the application of single-parent training group (SPG) programs to three parent–child dyads exposed to distressed family circumstances. Methods: Single-system evaluation designs were conducted with two single birth parents, one single foster parent, and each parent’s three respective children, in an effort to appraise the results of a SPG program. Results: Two of the three parent–child dyads benefited from the SPG. Results suggested that there were changes in parent reinforcement and attention behaviors and children’s noncompliance behaviors. Conclusion: Behavioral improvements in single parent and child dyads lend support for the effectiveness of the parent training group for single parents. Implications for practice and future research on SPG programs are discussed. Close

• 45. [Article] NWA 8614: The Least Heated Winonaite

  Northwest Africa 8614 is classified as a winonaite on the basis of oxygen isotope ratios, mineralogy, and highly reduced chemistry. Unlike other winonaites, it contains numerous and readily apparent chondrules. ...

  Citation × Citation Citation Abstract Copy Title: NWA 8614: The Least Heated Winonaite Author: Farley, Karla, Ruzicka, Alexander M., Armstrong, Katherine Year: 2015 Northwest Africa 8614 is classified as a winonaite on the basis of oxygen isotope ratios, mineralogy, and highly reduced chemistry. Unlike other winonaites, it contains numerous and readily apparent chondrules. Here we discuss various features of NWA 8614 and the possible significance of the meteorite. Petrological and chemical analyses were performed using optical microscopy with a DM2500 Leica petrographic microscope and a Zeiss Sigma VP-FEG scanning electron microscope (SEM) with a high-efficiency energy dispersive spectrometer (EDS). Oxygen isotopes were analyzed by Karen Ziegler at the University of New Mexico on acid-washed samples to remove terrestrial weathering products. Owing to the abundance of chondrules, NWA 8641 may be one of the least heated winonaites, and therefore may provide clues to the chondritic protolith of the winonaite parent body. Overall textures are similar to those found in type 6 chondrites that escaped significant melting. Despite similar geothermometer temperatures for various mineral pairs, NWA 8614 apparently did not attain Fe-Mg equilibrium between olivine and pyroxene. Like other winonaites, NWA 8614 has olivine compositions that are too magnesian for equilibrium relative to low-Ca pyroxene. Among winonaites as a whole, there is no evidence for a curved trend between Fa and Fs compositions as would be expected for FeO-reduction during metamorphism [Benedix, et al 1998], nor for mineral compositions that correlate with geothermometry temperatures. This argues against a single metamorphic FeO-reduction trend from a common chondritic precursor. Instead, protoliths for different winonaites may have varied slightly in composition. Title: NWA 8614: The Least Heated Winonaite Author: Farley, Karla, Ruzicka, Alexander M., Armstrong, Katherine Year: 2015 Northwest Africa 8614 is classified as a winonaite on the basis of oxygen isotope ratios, mineralogy, and highly reduced chemistry. Unlike other winonaites, it contains numerous and readily apparent chondrules. Here we discuss various features of NWA 8614 and the possible significance of the meteorite. Petrological and chemical analyses were performed using optical microscopy with a DM2500 Leica petrographic microscope and a Zeiss Sigma VP-FEG scanning electron microscope (SEM) with a high-efficiency energy dispersive spectrometer (EDS). Oxygen isotopes were analyzed by Karen Ziegler at the University of New Mexico on acid-washed samples to remove terrestrial weathering products. Owing to the abundance of chondrules, NWA 8641 may be one of the least heated winonaites, and therefore may provide clues to the chondritic protolith of the winonaite parent body. Overall textures are similar to those found in type 6 chondrites that escaped significant melting. Despite similar geothermometer temperatures for various mineral pairs, NWA 8614 apparently did not attain Fe-Mg equilibrium between olivine and pyroxene. Like other winonaites, NWA 8614 has olivine compositions that are too magnesian for equilibrium relative to low-Ca pyroxene. Among winonaites as a whole, there is no evidence for a curved trend between Fa and Fs compositions as would be expected for FeO-reduction during metamorphism [Benedix, et al 1998], nor for mineral compositions that correlate with geothermometry temperatures. This argues against a single metamorphic FeO-reduction trend from a common chondritic precursor. Instead, protoliths for different winonaites may have varied slightly in composition. Close

• 46. [Article] Toward a Model of Work and Family Balance: How Families with Children Having Serious Emotional Disorders Manage Caregiving and Worklife

  Employed parents of children with serious emotional disorders must manage the competing demands of home and job. Although every situation is unique, all parents cope daily with the interface between employment ...

  Citation × Citation Citation Abstract Copy Title: Toward a Model of Work and Family Balance: How Families with Children Having Serious Emotional Disorders Manage Caregiving and Worklife Author: Rosenzweig, Julie M., Ogilvie, Alice Myrth, Brennan, Eileen M. Year: 1998 Employed parents of children with serious emotional disorders must manage the competing demands of home and job. Although every situation is unique, all parents cope daily with the interface between employment and home. As the number of single employed mothers and dual-worker households has increased, so has the research on work and family. A review of this literature offers an examination of the different ways work and family relate within the busy lives of employed parents. Three primary models emerge from the review that describe experiences of mothers and fathers challenged by meeting both the needs of family members and the responsibilities of work-life. The literature does not identify whether or not the parents have children with any special needs. This review serves as a foundation for research that will specifically focus on parents of children with serious emotional disorders. Title: Toward a Model of Work and Family Balance: How Families with Children Having Serious Emotional Disorders Manage Caregiving and Worklife Author: Rosenzweig, Julie M., Ogilvie, Alice Myrth, Brennan, Eileen M. Year: 1998 Employed parents of children with serious emotional disorders must manage the competing demands of home and job. Although every situation is unique, all parents cope daily with the interface between employment and home. As the number of single employed mothers and dual-worker households has increased, so has the research on work and family. A review of this literature offers an examination of the different ways work and family relate within the busy lives of employed parents. Three primary models emerge from the review that describe experiences of mothers and fathers challenged by meeting both the needs of family members and the responsibilities of work-life. The literature does not identify whether or not the parents have children with any special needs. This review serves as a foundation for research that will specifically focus on parents of children with serious emotional disorders. Close

• 47. [Article] Disease resistance and spring phenological characteristics of Ribes L. germplasm

  North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants ...

  Citation × Citation Citation Abstract Copy Title: Disease resistance and spring phenological characteristics of Ribes L. germplasm Author: Dalton, Daniel T. North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants and gooseberries would intensify the fungal disease white pine blister rust (WPBR) on five-needle pine (Pinus L. section Quinquefoliae) species. These pines were historically vital to the timber industry. Today, plant breeders seek to strengthen the Ribes small fruit industry through production of material suitable for North American conditions. Paramount to this effort is the development of resistance against major pests and diseases. Growers must be able to recognize the attributes of available genotypes prior to field establishment. The objectives of this research were to determine disease resistance and phenological characteristics of Ribes selections at the United States Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. Since the early 1930's, plant breeders have used immune black currant (R. nigrum L.) germplasm as a control tactic against the exotic WPBR, caused by the basidiomycete fungus Cronartium ribicola J.C. Fischer. In 1999, a seedling population was generated at the NCGR from a cross involving susceptible pistillate R. nigrum 'Ben Lomond' and immune staminate parent R. ussuriense Jancz. x R. nigrum 'Consort.' To test the inheritance of resistance in the F₁ population, aeciospore and urediniospore treatments were applied in 2008 to single-leaf softwood cuttings under controlled conditions in a greenhouse. Resistant F₁ phenotypes segregated in a 1:1 ratio consistent with the pattern of simple dominant inheritance of a single gene. Artificial inoculations testing aeciospore and urediniospore infectivity produced equivalent disease severity in the experimental Ribes genotypes. Resistance to the native powdery mildew fungus, Podosphaera mors-uvae (Schwein.) U. Brown and S. Takamatsu, was also evaluated in the F₁ population. Individuals segregated for resistance in a 1:3 ratio after exposure to elevated disease pressure in the greenhouse. Fifteen F₁ genotypes were resistant to both fungal pathogens and are candidates for further breeding trials. In a second study, five years of spring phenological survey data were analyzed using a growing degree-day (GDD) model, with the objective to identify cultivars adapted to North American conditions. Ribes section Calobotrya was the earliest group to reach "first bloom," followed sequentially by R. [superscript]xnidigrolaria Bauer hybrid species, section Symphocalyx, section Grossularia, section Ribes, and lastly, section Botrycarpum. Early and late-flowering accessions were identified for each taxon. Title: Disease resistance and spring phenological characteristics of Ribes L. germplasm Author: Dalton, Daniel T. North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants and gooseberries would intensify the fungal disease white pine blister rust (WPBR) on five-needle pine (Pinus L. section Quinquefoliae) species. These pines were historically vital to the timber industry. Today, plant breeders seek to strengthen the Ribes small fruit industry through production of material suitable for North American conditions. Paramount to this effort is the development of resistance against major pests and diseases. Growers must be able to recognize the attributes of available genotypes prior to field establishment. The objectives of this research were to determine disease resistance and phenological characteristics of Ribes selections at the United States Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. Since the early 1930's, plant breeders have used immune black currant (R. nigrum L.) germplasm as a control tactic against the exotic WPBR, caused by the basidiomycete fungus Cronartium ribicola J.C. Fischer. In 1999, a seedling population was generated at the NCGR from a cross involving susceptible pistillate R. nigrum 'Ben Lomond' and immune staminate parent R. ussuriense Jancz. x R. nigrum 'Consort.' To test the inheritance of resistance in the F₁ population, aeciospore and urediniospore treatments were applied in 2008 to single-leaf softwood cuttings under controlled conditions in a greenhouse. Resistant F₁ phenotypes segregated in a 1:1 ratio consistent with the pattern of simple dominant inheritance of a single gene. Artificial inoculations testing aeciospore and urediniospore infectivity produced equivalent disease severity in the experimental Ribes genotypes. Resistance to the native powdery mildew fungus, Podosphaera mors-uvae (Schwein.) U. Brown and S. Takamatsu, was also evaluated in the F₁ population. Individuals segregated for resistance in a 1:3 ratio after exposure to elevated disease pressure in the greenhouse. Fifteen F₁ genotypes were resistant to both fungal pathogens and are candidates for further breeding trials. In a second study, five years of spring phenological survey data were analyzed using a growing degree-day (GDD) model, with the objective to identify cultivars adapted to North American conditions. Ribes section Calobotrya was the earliest group to reach "first bloom," followed sequentially by R. [superscript]xnidigrolaria Bauer hybrid species, section Symphocalyx, section Grossularia, section Ribes, and lastly, section Botrycarpum. Early and late-flowering accessions were identified for each taxon. Close

• 48. [Article] Early genetic selection in Douglas-fir : interactions with shade, drought, and stand density

  This thesis is concerned with developing techniques for identifying "superior" Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) parent trees based on seedling progeny evaluation. The growth responses ...

  Citation × Citation Citation Abstract Copy Title: Early genetic selection in Douglas-fir : interactions with shade, drought, and stand density Author: Riitters, K. H. (Kurt H.) This thesis is concerned with developing techniques for identifying "superior" Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) parent trees based on seedling progeny evaluation. The growth responses of up to 14 open-pollinated families to shade, drought, and stand density were assessed in four experiments. A technique was developed to compare family height growth responses to increasing stand density while accounting for genetic variation in growth rates. Family rankings based on seedling evaluation criteria were compared with 15-year growth records for an earlier cohort from the same parent trees. The significant findings of this study were: (1) fifteen-year field height rankings were related to differences in budset date, height growth rate, and branchiness among seedlings grown with or without shade or drought stress; (2) seedling-field correlations were inversely related to seedling-seed weight correlations; (3) seedling-field correlations improved with age in the field; (L) family correlations between spaced-plant growth and closed-stand growth were low for measures of seedling size but high for measures of seedling shape, and; (5) there was genetic variation in height growth responses to increasing stand density in single-family seedling plots. Title: Early genetic selection in Douglas-fir : interactions with shade, drought, and stand density Author: Riitters, K. H. (Kurt H.) This thesis is concerned with developing techniques for identifying "superior" Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) parent trees based on seedling progeny evaluation. The growth responses of up to 14 open-pollinated families to shade, drought, and stand density were assessed in four experiments. A technique was developed to compare family height growth responses to increasing stand density while accounting for genetic variation in growth rates. Family rankings based on seedling evaluation criteria were compared with 15-year growth records for an earlier cohort from the same parent trees. The significant findings of this study were: (1) fifteen-year field height rankings were related to differences in budset date, height growth rate, and branchiness among seedlings grown with or without shade or drought stress; (2) seedling-field correlations were inversely related to seedling-seed weight correlations; (3) seedling-field correlations improved with age in the field; (L) family correlations between spaced-plant growth and closed-stand growth were low for measures of seedling size but high for measures of seedling shape, and; (5) there was genetic variation in height growth responses to increasing stand density in single-family seedling plots. Close

• 49. [Article] Spatial and temporal population dynamics of Cantharellus formosus, the Pacific Golden chanterelle, in Oregon

  This dissertation was undertaken to improve the understanding of the population dynamics of the Pacific Golden chanterelle, Cantharellus formosus. It addresses the longevity of individuals over a 12 year ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal population dynamics of Cantharellus formosus, the Pacific Golden chanterelle, in Oregon Author: Collins, Kelly Patrice This dissertation was undertaken to improve the understanding of the population dynamics of the Pacific Golden chanterelle, Cantharellus formosus. It addresses the longevity of individuals over a 12 year period and the limits of gene flow within the area of a 6,400 hectare watershed at the H.J. Andrews Long Term Ecological Research site and the 112 km square Willamette Valley of Oregon. I found that certain genets (i.e. genotypic individuals), called predominant genets, were able to survive for many years and inhabited an area of approximately 4 meters in diameter. Predominant genets produced sporocarps nearly every year, but many related and unrelated genets appeared and disappeared within the boundaries of that genet (as measured by sporocarps), especially in abundant or "good" years of sporocarp production. There was very little differentiation found between 9 plots in the the 6,400 hectare watershed (FST=0.001-0.008). Most differentiation was driven by one or two plots that differed in each of the years sampled (1998, 2000). Migration rates and genetic diversity also differed within the two years sampled. These results demonstrate the differences that occur between abundant years, when many different genets produce a single sporocarp, and less abundant years, when only the predominant genets produce sporocarps. The trend of little differentiation continued at the larger scale when the Willamette Valley was tested as a barrier to dispersal. I found no barrier to dispersal between the Coast Mountain Range and the Cascade Mountain Range that border the Willamette Valley. The two northernmost populations on the Coast Range showed somewhat larger differentiation, as did parameters between populations when evaluated by region. Analysis of molecular variance partitioned nearly twice the amount of variance to regions when calculated by genotypic frequencies (11%) as opposed to allelic frequencies (6%). This suggests that there is a tendency for genetic exchange between close populations. Differentiation was not supported by low estimated migration rates. These findings support a heirarchical dispersal scenario in which the majority of spores fall close to the parental sporocarp and mate with close neighbors. Other spores are captured in surface air currents and dispersed to other populations nearby. A few spores are transported to higher convection layers that disperse them many miles. The overall factor that limits the dispersal of C. formosus is not capacity to disperse, but more likely environmental factors such as availability of host trees like Douglas fir, Hemlock, and Sitka Spruce, proper moisture conditions of the soil, and low exchangeable acidity. Title: Spatial and temporal population dynamics of Cantharellus formosus, the Pacific Golden chanterelle, in Oregon Author: Collins, Kelly Patrice This dissertation was undertaken to improve the understanding of the population dynamics of the Pacific Golden chanterelle, Cantharellus formosus. It addresses the longevity of individuals over a 12 year period and the limits of gene flow within the area of a 6,400 hectare watershed at the H.J. Andrews Long Term Ecological Research site and the 112 km square Willamette Valley of Oregon. I found that certain genets (i.e. genotypic individuals), called predominant genets, were able to survive for many years and inhabited an area of approximately 4 meters in diameter. Predominant genets produced sporocarps nearly every year, but many related and unrelated genets appeared and disappeared within the boundaries of that genet (as measured by sporocarps), especially in abundant or "good" years of sporocarp production. There was very little differentiation found between 9 plots in the the 6,400 hectare watershed (FST=0.001-0.008). Most differentiation was driven by one or two plots that differed in each of the years sampled (1998, 2000). Migration rates and genetic diversity also differed within the two years sampled. These results demonstrate the differences that occur between abundant years, when many different genets produce a single sporocarp, and less abundant years, when only the predominant genets produce sporocarps. The trend of little differentiation continued at the larger scale when the Willamette Valley was tested as a barrier to dispersal. I found no barrier to dispersal between the Coast Mountain Range and the Cascade Mountain Range that border the Willamette Valley. The two northernmost populations on the Coast Range showed somewhat larger differentiation, as did parameters between populations when evaluated by region. Analysis of molecular variance partitioned nearly twice the amount of variance to regions when calculated by genotypic frequencies (11%) as opposed to allelic frequencies (6%). This suggests that there is a tendency for genetic exchange between close populations. Differentiation was not supported by low estimated migration rates. These findings support a heirarchical dispersal scenario in which the majority of spores fall close to the parental sporocarp and mate with close neighbors. Other spores are captured in surface air currents and dispersed to other populations nearby. A few spores are transported to higher convection layers that disperse them many miles. The overall factor that limits the dispersal of C. formosus is not capacity to disperse, but more likely environmental factors such as availability of host trees like Douglas fir, Hemlock, and Sitka Spruce, proper moisture conditions of the soil, and low exchangeable acidity. Close

• 50. [Article] The heritability of agronomic characteristics in tall fescue (Festuca arundinacea Schreb.)

  Three genotypes of tall fescue (Festuca arundinacea Schreb. cultivar Fawn and four genotypes from the cultivar Fortune were used as parents to form 15 of a possible 21 single crosses to study the heritability ...

  Citation × Citation Citation Abstract Copy Title: The heritability of agronomic characteristics in tall fescue (Festuca arundinacea Schreb.) Author: Subhanij, Thiravira Three genotypes of tall fescue (Festuca arundinacea Schreb. cultivar Fawn and four genotypes from the cultivar Fortune were used as parents to form 15 of a possible 21 single crosses to study the heritability of certain agronomic characteristics. The Fawn variety is considered to be tall in growth habit, vigorous and early in anthesis. The Fortune variety represents germ plasm with a shorter growth habit, less vigor and later anthesis. Crossing was accomplished by mutual pollination in the greenhouse during February 1972. A greenhouse experiment was started in June 1972 using the 15 single crosses in a randomized block with three replications. Plants were supplied with one half strength of a modified Hougland's solution twice weekly until August 3 followed with an application of the same nutrient solution every two weeks until they were taken to the field for establishment. Greenhouse data were collected on July 7, August 4 and September 11. These data indicated that the variation among single crosses for tiller numbers and dry weight were greater as the plant grew older. Nutrient stress affected dry matter yield by reducing the variation and mean performance of the single crosses. Differences among single crosses for shoot length, tiller number, and plant spread were still quite evident under the stress conditions. Shoot length showed significant general combining ability (GCA) with non significant specific combining ability effects (SCA) on July 7 and September 11. GCA effects for tiller numbers were evident on August 4 and September 11. Both GCA and SCA effects were significant for plant spread on September ii. GCA for dry weight were significant only on July 7. Based on the diallel analysis, additive gene action was primarily responsible for shoot length, tiller numbers and dry weight. Both additive and non additive gene action influenced plant spread. The field establishment included the 15 single crosses from greenhouse experiments and the seven parent clones, established in a randomized block design with three replications. From the diallel analysis, it was observed that the GCA:SCA mean square for the characters measured were: plant height (19:1), plant spread (2. 1:1), anthesis date (3.2:1), panicle number (1.4:1), panicle length(l2:1), number of primary pedicels per panicle (7.4:1), five panicle seed weight (0. 2:1), seed yield per plant (0. 4:1) and 100 seed weight (15.1:1). This indicated that additive gene action was of major importance in the expression of plant height, number of primary pedicels and 100 seed weight. Non additive gene action was contributed substantially more to the expression of five panicles seed weight and seed yield. Both additive and non additive gene action contributed to plant spread and anthesis. Inferences about gene action for panicle numbers and panicle length were not as evident. This is because of the low GCA:SCA ratio, a barely significant GCA for panicle number, and no significant GCA or SCA for panicle length. Single cross progeny were superior to mid parent for plant height (9.27 percent), plant spread (20. 33 percent), anthesis (20.90 percent, which suggested earlier anthesis than mid parent), panicle number (36. 69 percent), and panicle length (11. 44 percent). No apparent superiority of single cross progeny over their corresponding mid parent for number of primary pedicels and 100 seed weight was observed. Of all single crosses, only Fawn x Fortune crosses were inferior to mid parents for five panicle seed weight (65.93 percent) and seed yield (60. 22 percent). The Fawn x Fortune performance for both of these characters (0.4062 and 1.23 g per plant, respectively)was low, The diverse parentage of these crosses may have resulted in irregular meiotic behavior in the F₁ which in turn may have caused inviable gametes to be formed. This sterility would result in the low seed yields observed. This is a problem that should be cytologically investigated. Crosses between diverse germ plasm (Fawn x Fortune crosses) did result, however, in heterosis for all characteristics except number of primary pedicels and 100 seed weight. But Fortune x Fortune crosses, for certain characters such as plant height, plant spread, panicle numbers, panicle length,exhibited even more heterosis. No heterosis was observed in the Fawn x Fawn crosses. Medium to high heritability estimates were observed for 100 seed weight, plant spread, anthesis date, panicle number and panicle length, while medium to low heritability were observed for panicle length. Low heritable value was evident for plant height, number of primary pedicels, five panicle seed weight and seed yield. Heritability estimates were based on parent progeny relationships involving all single crosses and mid parents. The relationships among various plant characteristics and seed yield was studied. Five panicle seed weight and panicle numbers were significantly correlated with seed yield. However there was a non-significant association of panicle length with seed yield and number of primary pedicels with seed yield.These relationships suggest that higher yielding genotypes may be identified by observing only few panicles per plants. The panicle characteristics examined in this study (other than seed weight) were of little value in identifying high seed yield genotypes, but panicle seed weight was positively related to plant yield. Title: The heritability of agronomic characteristics in tall fescue (Festuca arundinacea Schreb.) Author: Subhanij, Thiravira Three genotypes of tall fescue (Festuca arundinacea Schreb. cultivar Fawn and four genotypes from the cultivar Fortune were used as parents to form 15 of a possible 21 single crosses to study the heritability of certain agronomic characteristics. The Fawn variety is considered to be tall in growth habit, vigorous and early in anthesis. The Fortune variety represents germ plasm with a shorter growth habit, less vigor and later anthesis. Crossing was accomplished by mutual pollination in the greenhouse during February 1972. A greenhouse experiment was started in June 1972 using the 15 single crosses in a randomized block with three replications. Plants were supplied with one half strength of a modified Hougland's solution twice weekly until August 3 followed with an application of the same nutrient solution every two weeks until they were taken to the field for establishment. Greenhouse data were collected on July 7, August 4 and September 11. These data indicated that the variation among single crosses for tiller numbers and dry weight were greater as the plant grew older. Nutrient stress affected dry matter yield by reducing the variation and mean performance of the single crosses. Differences among single crosses for shoot length, tiller number, and plant spread were still quite evident under the stress conditions. Shoot length showed significant general combining ability (GCA) with non significant specific combining ability effects (SCA) on July 7 and September 11. GCA effects for tiller numbers were evident on August 4 and September 11. Both GCA and SCA effects were significant for plant spread on September ii. GCA for dry weight were significant only on July 7. Based on the diallel analysis, additive gene action was primarily responsible for shoot length, tiller numbers and dry weight. Both additive and non additive gene action influenced plant spread. The field establishment included the 15 single crosses from greenhouse experiments and the seven parent clones, established in a randomized block design with three replications. From the diallel analysis, it was observed that the GCA:SCA mean square for the characters measured were: plant height (19:1), plant spread (2. 1:1), anthesis date (3.2:1), panicle number (1.4:1), panicle length(l2:1), number of primary pedicels per panicle (7.4:1), five panicle seed weight (0. 2:1), seed yield per plant (0. 4:1) and 100 seed weight (15.1:1). This indicated that additive gene action was of major importance in the expression of plant height, number of primary pedicels and 100 seed weight. Non additive gene action was contributed substantially more to the expression of five panicles seed weight and seed yield. Both additive and non additive gene action contributed to plant spread and anthesis. Inferences about gene action for panicle numbers and panicle length were not as evident. This is because of the low GCA:SCA ratio, a barely significant GCA for panicle number, and no significant GCA or SCA for panicle length. Single cross progeny were superior to mid parent for plant height (9.27 percent), plant spread (20. 33 percent), anthesis (20.90 percent, which suggested earlier anthesis than mid parent), panicle number (36. 69 percent), and panicle length (11. 44 percent). No apparent superiority of single cross progeny over their corresponding mid parent for number of primary pedicels and 100 seed weight was observed. Of all single crosses, only Fawn x Fortune crosses were inferior to mid parents for five panicle seed weight (65.93 percent) and seed yield (60. 22 percent). The Fawn x Fortune performance for both of these characters (0.4062 and 1.23 g per plant, respectively)was low, The diverse parentage of these crosses may have resulted in irregular meiotic behavior in the F₁ which in turn may have caused inviable gametes to be formed. This sterility would result in the low seed yields observed. This is a problem that should be cytologically investigated. Crosses between diverse germ plasm (Fawn x Fortune crosses) did result, however, in heterosis for all characteristics except number of primary pedicels and 100 seed weight. But Fortune x Fortune crosses, for certain characters such as plant height, plant spread, panicle numbers, panicle length,exhibited even more heterosis. No heterosis was observed in the Fawn x Fawn crosses. Medium to high heritability estimates were observed for 100 seed weight, plant spread, anthesis date, panicle number and panicle length, while medium to low heritability were observed for panicle length. Low heritable value was evident for plant height, number of primary pedicels, five panicle seed weight and seed yield. Heritability estimates were based on parent progeny relationships involving all single crosses and mid parents. The relationships among various plant characteristics and seed yield was studied. Five panicle seed weight and panicle numbers were significantly correlated with seed yield. However there was a non-significant association of panicle length with seed yield and number of primary pedicels with seed yield.These relationships suggest that higher yielding genotypes may be identified by observing only few panicles per plants. The panicle characteristics examined in this study (other than seed weight) were of little value in identifying high seed yield genotypes, but panicle seed weight was positively related to plant yield. Close