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• 61. [Article] The breeding behavior of forage yield in two populations of tall fescue, (Festuca arundinacea, Schreb.)

  The single-cross and most F₂ progenies of 19 genotypes of tall fescue (Festuca arundinacea, Schreb. ) were used to study the breeding behavior of forage yield. Parental genotypes were selected for high ...

  Citation × Citation Citation Abstract Copy Title: The breeding behavior of forage yield in two populations of tall fescue, (Festuca arundinacea, Schreb.) Author: Matheson, Keith Isom The single-cross and most F₂ progenies of 19 genotypes of tall fescue (Festuca arundinacea, Schreb. ) were used to study the breeding behavior of forage yield. Parental genotypes were selected for high self-sterility, high chromogen and high crude protein. These were studied in two groups of nine intermediate and ten late-flowering genotypes. Progenies were grown on the Hyslop Agronomy Farm, Corvallis, Oregon as plants spaced one foot apart with three feet between rows. Ten plants of each cross for each generation were arranged in a randomized block design with four replications. Variables measured were plant width, natural plant height, plant spread, leaf length, total plant height of regrowth tissue, plant density and forage yield. The collected data were converted to plant means. Broad- and narrow-sense estimates of heritability were obtained from expected mean squares according to Griffing's analysis (random model, method four) and compared with estimates of heritability obtained by F₂-single-cross regression. General and specific combining ability effects were observed and the single-cross-F₂ inbreeding depressions were studied. The F₂ families were obtained by the self-pollination of five single-cross plants. General combining ability mean squares averaged from two to nine times greater than the mean squares for specific combining ability, with the largest difference being 54.7 times greater. The two populations responded similarly for the variables measured except for total plant height and plant spread. Greater progress from selection could be expected in the late- maturing group with the exception of these two traits. In most cases, single-cross progenies performed better than their corresponding F₂ progenies. The average of all single-crosses differed from the average of all F₂ progenies in 12 of 20 analyses in 1963, but in only 2 of 12 in 1964. The inbreeding characteristic was most pronounced for forage yield. High-performing single-crosses for the traits studied tended to produce high-performing F₂ progenies. Little or no heterosis was expressed and the expression of inbreeding depression appeared to be influenced greatly by the environment. Heritability estimates indicated that most traits could be studied more effectively after the second year of plant establishment. The environmental influence appeared to be less pronounced at that time. Where the coefficient of determination was high between the single-cross and F₂ generations, traits were less influenced by the environment and the disparity between the estimates of heritability was less. When used on cross-pollinated polyploid grasses, the method of diallel analysis proposed by Griffing does not appear to remove all environmental influence and thus overestimates heritability. Forage yield in the two populations of tall fescue studied was governed principally by additive gene action. Heterosis expressed was mostly in crosses involving low-performing parents. Title: The breeding behavior of forage yield in two populations of tall fescue, (Festuca arundinacea, Schreb.) Author: Matheson, Keith Isom The single-cross and most F₂ progenies of 19 genotypes of tall fescue (Festuca arundinacea, Schreb. ) were used to study the breeding behavior of forage yield. Parental genotypes were selected for high self-sterility, high chromogen and high crude protein. These were studied in two groups of nine intermediate and ten late-flowering genotypes. Progenies were grown on the Hyslop Agronomy Farm, Corvallis, Oregon as plants spaced one foot apart with three feet between rows. Ten plants of each cross for each generation were arranged in a randomized block design with four replications. Variables measured were plant width, natural plant height, plant spread, leaf length, total plant height of regrowth tissue, plant density and forage yield. The collected data were converted to plant means. Broad- and narrow-sense estimates of heritability were obtained from expected mean squares according to Griffing's analysis (random model, method four) and compared with estimates of heritability obtained by F₂-single-cross regression. General and specific combining ability effects were observed and the single-cross-F₂ inbreeding depressions were studied. The F₂ families were obtained by the self-pollination of five single-cross plants. General combining ability mean squares averaged from two to nine times greater than the mean squares for specific combining ability, with the largest difference being 54.7 times greater. The two populations responded similarly for the variables measured except for total plant height and plant spread. Greater progress from selection could be expected in the late- maturing group with the exception of these two traits. In most cases, single-cross progenies performed better than their corresponding F₂ progenies. The average of all single-crosses differed from the average of all F₂ progenies in 12 of 20 analyses in 1963, but in only 2 of 12 in 1964. The inbreeding characteristic was most pronounced for forage yield. High-performing single-crosses for the traits studied tended to produce high-performing F₂ progenies. Little or no heterosis was expressed and the expression of inbreeding depression appeared to be influenced greatly by the environment. Heritability estimates indicated that most traits could be studied more effectively after the second year of plant establishment. The environmental influence appeared to be less pronounced at that time. Where the coefficient of determination was high between the single-cross and F₂ generations, traits were less influenced by the environment and the disparity between the estimates of heritability was less. When used on cross-pollinated polyploid grasses, the method of diallel analysis proposed by Griffing does not appear to remove all environmental influence and thus overestimates heritability. Forage yield in the two populations of tall fescue studied was governed principally by additive gene action. Heterosis expressed was mostly in crosses involving low-performing parents. Close

• 62. [Article] Highland Magnet School at Kenwood: School Improvement Plan Dashboard

  Single-page poster.

  Citation × Citation Citation Abstract Copy Title: Highland Magnet School at Kenwood: School Improvement Plan Dashboard Author: Dean, Paul Year: 2013, 2012 Single-page poster. Title: Highland Magnet School at Kenwood: School Improvement Plan Dashboard Author: Dean, Paul Year: 2013, 2012 Single-page poster. Close

• 63. [Article] Consequential Validity Evidence for Oregon's Extended Assessment

  Single page poster

  Citation × Citation Citation Abstract Copy Title: Consequential Validity Evidence for Oregon's Extended Assessment Author: Farley, Daniel Year: 2013, 2012 Single page poster Title: Consequential Validity Evidence for Oregon's Extended Assessment Author: Farley, Daniel Year: 2013, 2012 Single page poster Close

• 64. [Image] Nude youths: 1508-1510, Sistine Chapel Ceiling

  	Printed on both sides of a single accordion folded piece of paper; Housed in a brown paper slip case; Slip case sealed with parental advisory label; Text printed accross center of images; Black and white ...
  	Citation × Citation Citation Abstract Copy Title: Nude youths: 1508-1510, Sistine Chapel Ceiling Author: Wirth, Karen Printed on both sides of a single accordion folded piece of paper; Housed in a brown paper slip case; Slip case sealed with parental advisory label; Text printed accross center of images; Black and white images of figures on the Sistine Chapel ceiling Title: Nude youths: 1508-1510, Sistine Chapel Ceiling Author: Wirth, Karen Printed on both sides of a single accordion folded piece of paper; Housed in a brown paper slip case; Slip case sealed with parental advisory label; Text printed accross center of images; Black and white images of figures on the Sistine Chapel ceiling Close

• 65. [Article] Genetic variation and interrelationships of acid detergent fiber, neutral detergent fiber, hemicellulose, crude protein and in vitro dry matter digestibility in tall fescue (Festuca arundinacea Schreb)

  Six parent clones and their 15 single-crosses of tall fescue (Festuca arundinaceae, Schreb) were row-planted in Corvallis, Oregon, row and sward-planted in Columbia, Missouri, and evaluated for genetic ...

  Citation × Citation Citation Abstract Copy Title: Genetic variation and interrelationships of acid detergent fiber, neutral detergent fiber, hemicellulose, crude protein and in vitro dry matter digestibility in tall fescue (Festuca arundinacea Schreb) Author: Soh, Aik-chin Six parent clones and their 15 single-crosses of tall fescue (Festuca arundinaceae, Schreb) were row-planted in Corvallis, Oregon, row and sward-planted in Columbia, Missouri, and evaluated for genetic variability, genotyp-eenvironment interactions and interrelationships in acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose (HCL), crude protein (CP) and in vitro dry matter digestibility (IVDMD) for each harvest in 1977 and 1978. Analyses revealed that general combining ability or additive genetic effects predominated for all the measured characteristics in the tall fescue diallel cross population. Of the genotype-environment interactions, only general combining ability x harvest interaction effects were significant enough to warrant consideration. The results also suggest that general combining ability of the parents rather than actual parental performance is a better predictor of hybrid progeny performance for all the characteristics. Parent-progeny regressions reveal that ADF is a more transmissible trait than NDF, IVDMD, HCL, or CP. ADF and NDF were highly and significantly correlated to IVDMD while HCL and CP were poorly correlated to IVDMD. It is suggested that the results obtained can have wider applicability to other tall fescue growing areas and populations. The results indicate that a selection program based on progeny testing for general combining ability for low ADF under row-planted conditions in one location for all harvest seasons over one or two years would efficiently and conveniently result in a rapid indirect selection improvement for digestibility in tall fescue. Title: Genetic variation and interrelationships of acid detergent fiber, neutral detergent fiber, hemicellulose, crude protein and in vitro dry matter digestibility in tall fescue (Festuca arundinacea Schreb) Author: Soh, Aik-chin Six parent clones and their 15 single-crosses of tall fescue (Festuca arundinaceae, Schreb) were row-planted in Corvallis, Oregon, row and sward-planted in Columbia, Missouri, and evaluated for genetic variability, genotyp-eenvironment interactions and interrelationships in acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose (HCL), crude protein (CP) and in vitro dry matter digestibility (IVDMD) for each harvest in 1977 and 1978. Analyses revealed that general combining ability or additive genetic effects predominated for all the measured characteristics in the tall fescue diallel cross population. Of the genotype-environment interactions, only general combining ability x harvest interaction effects were significant enough to warrant consideration. The results also suggest that general combining ability of the parents rather than actual parental performance is a better predictor of hybrid progeny performance for all the characteristics. Parent-progeny regressions reveal that ADF is a more transmissible trait than NDF, IVDMD, HCL, or CP. ADF and NDF were highly and significantly correlated to IVDMD while HCL and CP were poorly correlated to IVDMD. It is suggested that the results obtained can have wider applicability to other tall fescue growing areas and populations. The results indicate that a selection program based on progeny testing for general combining ability for low ADF under row-planted conditions in one location for all harvest seasons over one or two years would efficiently and conveniently result in a rapid indirect selection improvement for digestibility in tall fescue. Close

• 66. [Article] Do Family Risk Classes Predict Attrition in Parent Child Interaction Therapy?

  Child behavior disorders are the second most prevalent form of mental illness affecting children in the United States (Perou et al., 2013), with lifetime prevalence estimated at 10% (Nock, Kazdin, Hiripi ...

  Citation × Citation Citation Abstract Copy Title: Do Family Risk Classes Predict Attrition in Parent Child Interaction Therapy? Author: Hartman, Grace M. Child behavior disorders are the second most prevalent form of mental illness affecting children in the United States (Perou et al., 2013), with lifetime prevalence estimated at 10% (Nock, Kazdin, Hiripi & Kessler, 2007). Negative outcomes associated with ODD during childhood and adolescence include conflict in families, poor peer relationships, peer rejection, and academic difficulties (Burke, Rowe & Boylan, 2013). Parent training programs are shown to be effective in reducing child behavior disorders (Thomas & Zimmer-Gembeck, 2011). One such program, Parent Child Interaction Therapy (PCIT), is a widely disseminated intervention implemented in diverse settings with populations of at-risk families. PCIT is an intervention shown to be effective in preventing and reducing behavior disorders in children aged 2- to 7- years old (Brinkmeyer & Eyberg, 2003). However, a large barrier to treatment success is that families often dropout before therapy is completed (Fernandez & Eyberg, 2009). A small collection of studies specifically examining attrition in PCIT have explored family risks as treatment barriers. Models exploring the shared influence of multiple risk factors in the literature on PCIT attrition are uncommon, but given the co-occurring contextual risks often seen in families enrolled in PCIT, studies documenting the shared influence of multiple risks on attrition are important and have potential value in research and practice. Studies associating family risks with PCIT attrition have typically operationalized single variables and findings have been inconsistent. Although children and parents in parent-child therapies are known to have adverse family experiences (i.e. abuse, neglect, witnessing violence) (Kazdin, 1996), studies on the influence of adverse family experiences in PCIT attrition are few, and none have looked at the combined influences of family risks. To help address these gaps, the current study will examined the ways in which family risks operate in combination with one another to help explain attrition in PCIT. More specifically, this study examines whether or not families participating in PCIT differ not only in the number of risks they present, but also in the ways in which risks combine, forming distinct patterns of risks. To address this question, we conduct a Latent Class Analysis to identify family risk classes examining how two overarching types of risk; low-SES, and adverse family experiences. We addressed our main study aim by examining how the classes predicted the likelihood of dropping out of PCIT overall, and prior to the completion of the CDI component. To help address these gaps, the current study will examine the ways in which family risks operate in combination with one another to help explain attrition in PCIT. More specifically, this study examines whether or not families participating in PCIT differ not only in the number of risks they present, but also in the ways in which risks combine, forming distinct patterns of risks. The goals of the present study were to explore patterns of risks among families participating in PCIT, and to examine associations between these patterns and the likelihood of dropping out of PCIT, both prior to completing the first component (CDI) of the therapy and prior to completion of the full program. Findings pointed to three distinct patterns of risk but did not detect any significant associations between these patterns of risk and attrition in PCIT. These findings are important for guiding future research and provide preliminary information for practitioners to better understand the complexity of risks among families attending PCIT. Although the primary study aim was to examine links between classes of risk and attrition in PCIT, preliminary analysis detected two specific risk variables linked with PCIT attrition prior to completion of CDI: low parental education and having a mental health disorder in the household. There was also a trend toward low parental education being associated with attrition from PCIT overall Title: Do Family Risk Classes Predict Attrition in Parent Child Interaction Therapy? Author: Hartman, Grace M. Child behavior disorders are the second most prevalent form of mental illness affecting children in the United States (Perou et al., 2013), with lifetime prevalence estimated at 10% (Nock, Kazdin, Hiripi & Kessler, 2007). Negative outcomes associated with ODD during childhood and adolescence include conflict in families, poor peer relationships, peer rejection, and academic difficulties (Burke, Rowe & Boylan, 2013). Parent training programs are shown to be effective in reducing child behavior disorders (Thomas & Zimmer-Gembeck, 2011). One such program, Parent Child Interaction Therapy (PCIT), is a widely disseminated intervention implemented in diverse settings with populations of at-risk families. PCIT is an intervention shown to be effective in preventing and reducing behavior disorders in children aged 2- to 7- years old (Brinkmeyer & Eyberg, 2003). However, a large barrier to treatment success is that families often dropout before therapy is completed (Fernandez & Eyberg, 2009). A small collection of studies specifically examining attrition in PCIT have explored family risks as treatment barriers. Models exploring the shared influence of multiple risk factors in the literature on PCIT attrition are uncommon, but given the co-occurring contextual risks often seen in families enrolled in PCIT, studies documenting the shared influence of multiple risks on attrition are important and have potential value in research and practice. Studies associating family risks with PCIT attrition have typically operationalized single variables and findings have been inconsistent. Although children and parents in parent-child therapies are known to have adverse family experiences (i.e. abuse, neglect, witnessing violence) (Kazdin, 1996), studies on the influence of adverse family experiences in PCIT attrition are few, and none have looked at the combined influences of family risks. To help address these gaps, the current study will examined the ways in which family risks operate in combination with one another to help explain attrition in PCIT. More specifically, this study examines whether or not families participating in PCIT differ not only in the number of risks they present, but also in the ways in which risks combine, forming distinct patterns of risks. To address this question, we conduct a Latent Class Analysis to identify family risk classes examining how two overarching types of risk; low-SES, and adverse family experiences. We addressed our main study aim by examining how the classes predicted the likelihood of dropping out of PCIT overall, and prior to the completion of the CDI component. To help address these gaps, the current study will examine the ways in which family risks operate in combination with one another to help explain attrition in PCIT. More specifically, this study examines whether or not families participating in PCIT differ not only in the number of risks they present, but also in the ways in which risks combine, forming distinct patterns of risks. The goals of the present study were to explore patterns of risks among families participating in PCIT, and to examine associations between these patterns and the likelihood of dropping out of PCIT, both prior to completing the first component (CDI) of the therapy and prior to completion of the full program. Findings pointed to three distinct patterns of risk but did not detect any significant associations between these patterns of risk and attrition in PCIT. These findings are important for guiding future research and provide preliminary information for practitioners to better understand the complexity of risks among families attending PCIT. Although the primary study aim was to examine links between classes of risk and attrition in PCIT, preliminary analysis detected two specific risk variables linked with PCIT attrition prior to completion of CDI: low parental education and having a mental health disorder in the household. There was also a trend toward low parental education being associated with attrition from PCIT overall Close

• 67. [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

• 68. [Article] The transition of single mothers on public assistance to economic self-sufficiency : an analysis of human capital, family resource, employment and psychosocial factors

  The study explored a model that integrates human capital, family resource, employment and psychosocial factors to explain variation in economic self-sufficiency (ESS) among single mothers. A sample of ...

  Citation × Citation Citation Abstract Copy Title: The transition of single mothers on public assistance to economic self-sufficiency : an analysis of human capital, family resource, employment and psychosocial factors Author: Parker, Louise Anne The study explored a model that integrates human capital, family resource, employment and psychosocial factors to explain variation in economic self-sufficiency (ESS) among single mothers. A sample of 851 single mothers on Aid to Families with Dependent Children was selected from the Washington State Family Income Study data base. Data from a three-year period (6/88-5/91) were utilized to describe and analyze single mothers in transition from welfare. When compared to a sample of non-poor single mothers, mothers on public assistance differed significantly in several ways: They were younger, had more children and were more likely to have parents who received public assistance. Educational levels were significantly lower, as was employment activity. Economic self-sufficiency was measured as the ratio of welfare benefits to household income. Degree of ESS improved over the three-year period: While 60 percent of single mothers relied on welfare for more than half their income in the first year, only 45 percent did by the third year. In analyzing differences in degrees of economic self-sufficiency among single mothers, the following groups of mothers had significantly higher degrees of welfare reliance: never-married and divorced mothers; mothers with a child under age two; mothers with three or more children; non-white mothers; and mothers living in public housing. A path analysis was conducted to determine the relative influence of human capital, family resource, employment and psychosocial factors on later economic self-sufficiency. Number of children and receipt of subsidies positively affected welfare reliance. Education, number of adults in the household and number of months employed negatively affected degree of welfare reliance. A key finding was that, after controlling for differences in human capital, family resources and employment activity, workplace support retained a highly significant, inverse relationship with degree of welfare reliance. Sense of personal control and social support had both direct and indirect effects on degree of welfare reliance, establishing that psychosocial factors mediate impacts of human capital, family and employment factors on economic self-sufficiency. The results support the viability of utilizing stress models to examine objective economic outcomes in future research. Title: The transition of single mothers on public assistance to economic self-sufficiency : an analysis of human capital, family resource, employment and psychosocial factors Author: Parker, Louise Anne The study explored a model that integrates human capital, family resource, employment and psychosocial factors to explain variation in economic self-sufficiency (ESS) among single mothers. A sample of 851 single mothers on Aid to Families with Dependent Children was selected from the Washington State Family Income Study data base. Data from a three-year period (6/88-5/91) were utilized to describe and analyze single mothers in transition from welfare. When compared to a sample of non-poor single mothers, mothers on public assistance differed significantly in several ways: They were younger, had more children and were more likely to have parents who received public assistance. Educational levels were significantly lower, as was employment activity. Economic self-sufficiency was measured as the ratio of welfare benefits to household income. Degree of ESS improved over the three-year period: While 60 percent of single mothers relied on welfare for more than half their income in the first year, only 45 percent did by the third year. In analyzing differences in degrees of economic self-sufficiency among single mothers, the following groups of mothers had significantly higher degrees of welfare reliance: never-married and divorced mothers; mothers with a child under age two; mothers with three or more children; non-white mothers; and mothers living in public housing. A path analysis was conducted to determine the relative influence of human capital, family resource, employment and psychosocial factors on later economic self-sufficiency. Number of children and receipt of subsidies positively affected welfare reliance. Education, number of adults in the household and number of months employed negatively affected degree of welfare reliance. A key finding was that, after controlling for differences in human capital, family resources and employment activity, workplace support retained a highly significant, inverse relationship with degree of welfare reliance. Sense of personal control and social support had both direct and indirect effects on degree of welfare reliance, establishing that psychosocial factors mediate impacts of human capital, family and employment factors on economic self-sufficiency. The results support the viability of utilizing stress models to examine objective economic outcomes in future research. Close

• 69. [Article] A comparison of three systems of phenotypic selection for grain yield in three spring barley populations

  Concerns regarding the most effective means of evaluating segregating generations of spring barley prompted this investigation. Three methods of selection were considered: bulk, pedigree, and single seed ...

  Citation × Citation Citation Abstract Copy Title: A comparison of three systems of phenotypic selection for grain yield in three spring barley populations Author: Hayes, Patrick M. Concerns regarding the most effective means of evaluating segregating generations of spring barley prompted this investigation. Three methods of selection were considered: bulk, pedigree, and single seed descent. F₆ lines derived by each method were grown in a replicated yield trial. The effectiveness of each method was measured in terms of grain yield and four other agronomic traits. Continuity of method performance was evaluated across three spring barley populations. Parents used in developing these populations were chosen on the basis"of their diverse genetic backgrounds. Experimental populations differed for all agronomic traits measured. Differences between methods of selection were only found for 100 kernel weight, with lines from the single seed descent method being superior. The pedigree method was least effective for this trait. No significant differences between selection methods were found for plant height, spikes per meter, kernels per spike or grain yield. Significant differences were found between individual lines within methods and crosses for all traits except spikes per meter. There was no conclusive superiority of lines derived by any given method for any of the five traits. Although the single seed descent method was not significantly different from the pedigree and bulk methods on a mean basis, it did derive a number of superior individual lines and preserved substantial between-line variability for all traits measured, except spikes per meter. Because of the overall efficiency achieved with the single seed descent method, it may be a useful tool for the breeder of self-pollinated species. Title: A comparison of three systems of phenotypic selection for grain yield in three spring barley populations Author: Hayes, Patrick M. Concerns regarding the most effective means of evaluating segregating generations of spring barley prompted this investigation. Three methods of selection were considered: bulk, pedigree, and single seed descent. F₆ lines derived by each method were grown in a replicated yield trial. The effectiveness of each method was measured in terms of grain yield and four other agronomic traits. Continuity of method performance was evaluated across three spring barley populations. Parents used in developing these populations were chosen on the basis"of their diverse genetic backgrounds. Experimental populations differed for all agronomic traits measured. Differences between methods of selection were only found for 100 kernel weight, with lines from the single seed descent method being superior. The pedigree method was least effective for this trait. No significant differences between selection methods were found for plant height, spikes per meter, kernels per spike or grain yield. Significant differences were found between individual lines within methods and crosses for all traits except spikes per meter. There was no conclusive superiority of lines derived by any given method for any of the five traits. Although the single seed descent method was not significantly different from the pedigree and bulk methods on a mean basis, it did derive a number of superior individual lines and preserved substantial between-line variability for all traits measured, except spikes per meter. Because of the overall efficiency achieved with the single seed descent method, it may be a useful tool for the breeder of self-pollinated species. Close

• 70. [Article] Electrophoretic karyotypes and molecular genetic analysis of Tilletia caries and T. controversa

  Electrophoretic karyotypes were obtained from intact cells of four wild type strains of Tilletia caries and T. controversa, and 5 inter specific hybrid progeny using clamped homogeneous electric field, ...

  Citation × Citation Citation Abstract Copy Title: Electrophoretic karyotypes and molecular genetic analysis of Tilletia caries and T. controversa Author: Russell, Brian W. Electrophoretic karyotypes were obtained from intact cells of four wild type strains of Tilletia caries and T. controversa, and 5 inter specific hybrid progeny using clamped homogeneous electric field, pulsed field gel electrophoresis (CHEF PFGE). Each karyotype was polymorphic and unique relative to the other strains. However, the relative size range of all the chromosomes was consistent and typically ranged from approximately 850 to 4,490 kilobasepairs (Kb) for all strains, accept for two atypically small chromosomes in one strain of T. caries. The minimum estimated number of chromosomes was 19 or 20 for strains of T. controversa, 14 to 20 for T. caries, and from 19 to 22 for the hybrid progeny. The minimum estimated total genome size ranged from 28 to 39 megabasepairs (mb) for T. caries, 34 to 40 mb for T. controversa, and 36 to 42 mb for the hybrid progeny. Southern hybridization analysis performed with cloned, single copy homologous DNA fragments identified a single similar-sized chromosome in all strains. The maximum percent variability of the linkage groups defined by the single copy probes was 10% or less. The rDNA from Neurospora crassa hybridized with 2 or 3 chromosomes in the wild type stains of T. caries and T. controversa, and with 1 to 3 chromosomes in the hybrid progeny. The maximum percent variability among chromosomes that hybridized with the rDNA probe ranged from 35 to 40%. Either 1 or 2 chromosomes were identified by the single copy actin gene from Aspergillus nidulans, and the maximum percent variability ranged from 4 to 14% for these chromosomes. It was not possible to differentiate between the karyotypes of strains of either T. caries or T. controversa using the physical appearance of the karyotypes, the number and sizes of chromosomes, the genome sizes, or by Southern hybridization analysis. Analysis of the karyotypes of the hybrid progeny revealed that all were unique relative to each other and the parental stains, providing circumstantial evidence for the presence of recombinant chromosomes. That the genome size and chromosomes numbers of the hybrid progeny were similar to their monokaryotic parental strains strongly argues that the reduction division stage of meiosis had occurred. Seven teliospore samples from Oregon and Turkey were examined for their germination and autofluorescence properties. The teliospore samples were analyzed to determine if low temperature germination (0-4° C) and autofluorescing spore-wall reticulations associated with spores of T. controversa were usually linked. Two of the seven teliospore samples showed these characteristics to be unlinked. In an attempt to clone the mating type genes of T. caries and T. controversa, total genomic DNA was probed with a fragment of the b west mating type gene from Ustilago hordei. Although single 1.4 kb BamHI fragment from both pathogens was cloned by homology and sequenced, its role in mating type function remains uncertain. Title: Electrophoretic karyotypes and molecular genetic analysis of Tilletia caries and T. controversa Author: Russell, Brian W. Electrophoretic karyotypes were obtained from intact cells of four wild type strains of Tilletia caries and T. controversa, and 5 inter specific hybrid progeny using clamped homogeneous electric field, pulsed field gel electrophoresis (CHEF PFGE). Each karyotype was polymorphic and unique relative to the other strains. However, the relative size range of all the chromosomes was consistent and typically ranged from approximately 850 to 4,490 kilobasepairs (Kb) for all strains, accept for two atypically small chromosomes in one strain of T. caries. The minimum estimated number of chromosomes was 19 or 20 for strains of T. controversa, 14 to 20 for T. caries, and from 19 to 22 for the hybrid progeny. The minimum estimated total genome size ranged from 28 to 39 megabasepairs (mb) for T. caries, 34 to 40 mb for T. controversa, and 36 to 42 mb for the hybrid progeny. Southern hybridization analysis performed with cloned, single copy homologous DNA fragments identified a single similar-sized chromosome in all strains. The maximum percent variability of the linkage groups defined by the single copy probes was 10% or less. The rDNA from Neurospora crassa hybridized with 2 or 3 chromosomes in the wild type stains of T. caries and T. controversa, and with 1 to 3 chromosomes in the hybrid progeny. The maximum percent variability among chromosomes that hybridized with the rDNA probe ranged from 35 to 40%. Either 1 or 2 chromosomes were identified by the single copy actin gene from Aspergillus nidulans, and the maximum percent variability ranged from 4 to 14% for these chromosomes. It was not possible to differentiate between the karyotypes of strains of either T. caries or T. controversa using the physical appearance of the karyotypes, the number and sizes of chromosomes, the genome sizes, or by Southern hybridization analysis. Analysis of the karyotypes of the hybrid progeny revealed that all were unique relative to each other and the parental stains, providing circumstantial evidence for the presence of recombinant chromosomes. That the genome size and chromosomes numbers of the hybrid progeny were similar to their monokaryotic parental strains strongly argues that the reduction division stage of meiosis had occurred. Seven teliospore samples from Oregon and Turkey were examined for their germination and autofluorescence properties. The teliospore samples were analyzed to determine if low temperature germination (0-4° C) and autofluorescing spore-wall reticulations associated with spores of T. controversa were usually linked. Two of the seven teliospore samples showed these characteristics to be unlinked. In an attempt to clone the mating type genes of T. caries and T. controversa, total genomic DNA was probed with a fragment of the b west mating type gene from Ustilago hordei. Although single 1.4 kb BamHI fragment from both pathogens was cloned by homology and sequenced, its role in mating type function remains uncertain. Close