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• 51. [Article] Reproductive ecology and endocrinology of the garibaldi damselfish, Hypsypops rubicundus (Pomacentridae)

  I examined two aspects of the reproductive behavior of the garibaldi, Hypsypops rubicundus, a temperate marine damselfish with male parental care. My primary objective was to determine the relationship ...

  Citation × Citation Citation Abstract Copy Title: Reproductive ecology and endocrinology of the garibaldi damselfish, Hypsypops rubicundus (Pomacentridae) Author: Sikkel, Paul C. I examined two aspects of the reproductive behavior of the garibaldi, Hypsypops rubicundus, a temperate marine damselfish with male parental care. My primary objective was to determine the relationship between female choice and male parental investment in the care of offspring. In particular, I sought to determine: (1) how the presence and developmental stage of eggs already in the nest influences female spawning site choice; (2) how male investment in current offspring varies with the number and developmental stage of eggs in his nest; and (3) how patterns of mate choice and parental investment contribute to the reproductive success of each sex. Because male courtship and parental care behaviors change during a nesting cycle, a secondary objective was to indentify associated hormonal changes that potentially cause this change in behavior. Female garibaldi showed a strong preference to spawn in nests with early stage eggs over empty nests or those with predominantly late-stage eggs. Within nests containing eggs in multiple stages of development, females always deposited their eggs among the youngest eggs in the nest. Male garibaldi exhibited behavioral tactics that would increase the mortality of eggs deposited in empty nests (first clutches) or in older broods (late clutches) and thus favor such female preference. These include: (1) cannibalism of single-clutch broods; (2) cannibalism of older eggs early in the brood-cycle; (3) cannibalism of younger eggs late in the brood-cycle; (4) increased attentiveness of larger broods; and (5) increased aggressiveness in defense of larger broods. These behaviors are consistent with the predictions of parental investment theory that males invest in current offspring in a way that maximizes the net (current plus future) benefits of paternal care. Male garibaldi actively courted females when their nests were empty. However, courtship rates declined as males acquired eggs and as those eggs aged. This was concomitant with an increase in parental egg fanning. Levels of both testosterone and 11-ketotestosterone were positively related to levels of courtship activity and inversely related to male parental egg-fanning. Title: Reproductive ecology and endocrinology of the garibaldi damselfish, Hypsypops rubicundus (Pomacentridae) Author: Sikkel, Paul C. I examined two aspects of the reproductive behavior of the garibaldi, Hypsypops rubicundus, a temperate marine damselfish with male parental care. My primary objective was to determine the relationship between female choice and male parental investment in the care of offspring. In particular, I sought to determine: (1) how the presence and developmental stage of eggs already in the nest influences female spawning site choice; (2) how male investment in current offspring varies with the number and developmental stage of eggs in his nest; and (3) how patterns of mate choice and parental investment contribute to the reproductive success of each sex. Because male courtship and parental care behaviors change during a nesting cycle, a secondary objective was to indentify associated hormonal changes that potentially cause this change in behavior. Female garibaldi showed a strong preference to spawn in nests with early stage eggs over empty nests or those with predominantly late-stage eggs. Within nests containing eggs in multiple stages of development, females always deposited their eggs among the youngest eggs in the nest. Male garibaldi exhibited behavioral tactics that would increase the mortality of eggs deposited in empty nests (first clutches) or in older broods (late clutches) and thus favor such female preference. These include: (1) cannibalism of single-clutch broods; (2) cannibalism of older eggs early in the brood-cycle; (3) cannibalism of younger eggs late in the brood-cycle; (4) increased attentiveness of larger broods; and (5) increased aggressiveness in defense of larger broods. These behaviors are consistent with the predictions of parental investment theory that males invest in current offspring in a way that maximizes the net (current plus future) benefits of paternal care. Male garibaldi actively courted females when their nests were empty. However, courtship rates declined as males acquired eggs and as those eggs aged. This was concomitant with an increase in parental egg fanning. Levels of both testosterone and 11-ketotestosterone were positively related to levels of courtship activity and inversely related to male parental egg-fanning. Close

• 52. [Article] Exploring the Effects of Multi-Level Protective and Risk Factors on Child and Parenting Outcomes in Families Participating in Healthy Start/Healthy Families Oregon (HS/HFO)

  While many studies focus on the links between multiple risk factors and negative outcomes such as child maltreatment, less is known about the influence of protective factors in the face of risks. The theoretical ...

  Citation × Citation Citation Abstract Copy Title: Exploring the Effects of Multi-Level Protective and Risk Factors on Child and Parenting Outcomes in Families Participating in Healthy Start/Healthy Families Oregon (HS/HFO) Author: Nygren, Peggy Year: 2013 While many studies focus on the links between multiple risk factors and negative outcomes such as child maltreatment, less is known about the influence of protective factors in the face of risks. The theoretical base of this study was a social ecological model of interactive influences including individual parent, family, and neighborhood level factors to predict outcomes. Protective Factor Index (PFI) and Risk Factor Index (RFI) predictors were developed to explore potential multi-level protective factor buffering effects on key child development and parenting outcomes. Participants were first time mothers enrolled in a randomized controlled study of the Healthy Start/ Healthy Families Oregon (HS/HFO) home visitation program (treatment group) who completed a follow-up phone survey at the child’s 12 month birthday (n = 405). Families were offered HS/HFO services prenatally after meeting risk screening eligibility criteria on the New Baby Questionnaire (NBQ). Program mothers having received at least one home visit (n = 248) were included in the final analyses. Families had an average of 3.1 (SD = 1.2) NBQ risk factors at enrollment and 83% reported having trouble paying for basic needs. Families received an average of 16 home visits in the first 6 months of the program. Thirty-one percent of mothers were aged 19 or younger, 60% were White and Non-Hispanic, 31% were Hispanic, and 9% were another race/ethnicity. Hierarchical regression models with main effects (RFI, PFI, race) and an interaction term (RFI X PFI) were developed to predict eight outcomes. Interaction effects models were not significant. Five RFI main effects were significant: higher RFI scores were associated with greater likelihood of child welfare involvement, greater parenting stress, less favorable scores on child health and well-being, lower parent responsiveness and ii acceptance, and less supportive learning environments. One PFI main effect was significant: higher PFI scores predicted lower parenting stress. A trend level result showed higher PFI scores were associated with less child welfare involvement. Race was significant in two models: White/Non-Hispanic families were more likely to have a home visitor report child welfare involvement and had more frequent parent-child activities compared to other race/ethnicity families. Unpacking the results with separate single risk factor (12 items) and protective factor (10 items) regression models followed. Results showed parent’s prior family history of maltreatment and younger maternal age predicted child welfare involvement (home visitor report), while protection was seen for those with access to housing support. Social support and family functioning protectors were linked to lower parenting stress, while maternal depression showed the opposite finding. Better scores on a child health and well-being measure were seen with higher neighborhood cohesion and greater participation in HS/HFO; in contrast, neighborhood violence and frequent mobility were linked to worse scores. Developmentally supportive home environments were seen for families participating in additional parent support programs, in which the mother had greater knowledge of infant milestones and behavior, and if the family had access to housing supports. Unemployment proved to be associated with less enriched home environments. In summary, there was no support for the cumulative PFI in buffering risk for negative outcomes in this model. The RFI was also a more robust predictor of outcomes compared to the PFI in the main effects models. Overall, study findings provide some evidence for the utility of specific protective factors, as well as cumulative and specific single risk factors, for screening families for effectively targeting services and guiding the conceptual development of program and evaluation formats. Title: Exploring the Effects of Multi-Level Protective and Risk Factors on Child and Parenting Outcomes in Families Participating in Healthy Start/Healthy Families Oregon (HS/HFO) Author: Nygren, Peggy Year: 2013 While many studies focus on the links between multiple risk factors and negative outcomes such as child maltreatment, less is known about the influence of protective factors in the face of risks. The theoretical base of this study was a social ecological model of interactive influences including individual parent, family, and neighborhood level factors to predict outcomes. Protective Factor Index (PFI) and Risk Factor Index (RFI) predictors were developed to explore potential multi-level protective factor buffering effects on key child development and parenting outcomes. Participants were first time mothers enrolled in a randomized controlled study of the Healthy Start/ Healthy Families Oregon (HS/HFO) home visitation program (treatment group) who completed a follow-up phone survey at the child’s 12 month birthday (n = 405). Families were offered HS/HFO services prenatally after meeting risk screening eligibility criteria on the New Baby Questionnaire (NBQ). Program mothers having received at least one home visit (n = 248) were included in the final analyses. Families had an average of 3.1 (SD = 1.2) NBQ risk factors at enrollment and 83% reported having trouble paying for basic needs. Families received an average of 16 home visits in the first 6 months of the program. Thirty-one percent of mothers were aged 19 or younger, 60% were White and Non-Hispanic, 31% were Hispanic, and 9% were another race/ethnicity. Hierarchical regression models with main effects (RFI, PFI, race) and an interaction term (RFI X PFI) were developed to predict eight outcomes. Interaction effects models were not significant. Five RFI main effects were significant: higher RFI scores were associated with greater likelihood of child welfare involvement, greater parenting stress, less favorable scores on child health and well-being, lower parent responsiveness and ii acceptance, and less supportive learning environments. One PFI main effect was significant: higher PFI scores predicted lower parenting stress. A trend level result showed higher PFI scores were associated with less child welfare involvement. Race was significant in two models: White/Non-Hispanic families were more likely to have a home visitor report child welfare involvement and had more frequent parent-child activities compared to other race/ethnicity families. Unpacking the results with separate single risk factor (12 items) and protective factor (10 items) regression models followed. Results showed parent’s prior family history of maltreatment and younger maternal age predicted child welfare involvement (home visitor report), while protection was seen for those with access to housing support. Social support and family functioning protectors were linked to lower parenting stress, while maternal depression showed the opposite finding. Better scores on a child health and well-being measure were seen with higher neighborhood cohesion and greater participation in HS/HFO; in contrast, neighborhood violence and frequent mobility were linked to worse scores. Developmentally supportive home environments were seen for families participating in additional parent support programs, in which the mother had greater knowledge of infant milestones and behavior, and if the family had access to housing supports. Unemployment proved to be associated with less enriched home environments. In summary, there was no support for the cumulative PFI in buffering risk for negative outcomes in this model. The RFI was also a more robust predictor of outcomes compared to the PFI in the main effects models. Overall, study findings provide some evidence for the utility of specific protective factors, as well as cumulative and specific single risk factors, for screening families for effectively targeting services and guiding the conceptual development of program and evaluation formats. Close

• 53. [Image] Soils of the Klamath Indian Reservation; interim report, June 11, 1958

  	TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE ...
  	Citation × Citation Citation Abstract Copy Title: Soils of the Klamath Indian Reservation; interim report, June 11, 1958 Author: United States. Bureau of Indian Affairs Year: 1958, 2005, 2004 TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE 182 - 18 Climatic table, Sprague River, Oregon 185 Precipitation table , Chiloquin, Oregon 186 Temperature table, Chiloquin, Oregon 187 Climatic table, Fort Klamath, Oregon 188 VEGETATION 189 - 25 GEOLOGY 196 - 51 Hydrography: rivers, lakes, marshes, ground water 196 Relief and geological formations. 262e .32 Diatomite - tuff formation 262e . 1c4 Pliocene sediments of the Modoc Point area 262e.. 37 Faulted tuff formation 1c9 Pumice tuff formation.. 1d0 Pumice mantle and pumice flows ........ 262e.... .........40 Table of chemical analyses of pumice and scoria 1d5 Geology Map 262e . 262e 221 BIBLIOGRAPHY 262e 262e...52 PART II DESCRIPTIONS OF SOILS 223 - 60 Classification and survey 262e 262e.. 262e... 53 Soil profile and nomenclature. .... 262e...53 Chestnut Soils 262e 224 "Western" Brown Forest Soils 225 Regosol Soils . . 262e. 262e......56 Solonetz Soils 262e.....57 Halomorphic Soils 262e 228 Hydromorphic Soils 262e... 229 Soil Association Map 262e 229 KEY TO SOIL SERIES 262e61 - 63 SOIL SERIES AND MAPPING UNIT DESCRIPTIONS 134 ~ 254 APPENDIX 1955 - 297 Soil Series and mapping unit index. 2620. . . . 255 Glossary of terms 263f 262e. . . . 272 Table of soil analyses (Oregon State College)... 1989 Table of irrigation water quality (Oregon State College) 1990 Table of conductivity and reaction. . . . 1991 Table of resistance of saturated paste 262e296 Title: Soils of the Klamath Indian Reservation; interim report, June 11, 1958 Author: United States. Bureau of Indian Affairs Year: 1958, 2005, 2004 TABLE OF CONTENTS PART I INTRODUCTION 18 - 11 History and ethnology 18 Irrigated area table 19 Cultural geography 19 General physiographic features 262e . .3 Physiographic areas and farming 1d CLIMATE 182 - 18 Climatic table, Sprague River, Oregon 185 Precipitation table , Chiloquin, Oregon 186 Temperature table, Chiloquin, Oregon 187 Climatic table, Fort Klamath, Oregon 188 VEGETATION 189 - 25 GEOLOGY 196 - 51 Hydrography: rivers, lakes, marshes, ground water 196 Relief and geological formations. 262e .32 Diatomite - tuff formation 262e . 1c4 Pliocene sediments of the Modoc Point area 262e.. 37 Faulted tuff formation 1c9 Pumice tuff formation.. 1d0 Pumice mantle and pumice flows ........ 262e.... .........40 Table of chemical analyses of pumice and scoria 1d5 Geology Map 262e . 262e 221 BIBLIOGRAPHY 262e 262e...52 PART II DESCRIPTIONS OF SOILS 223 - 60 Classification and survey 262e 262e.. 262e... 53 Soil profile and nomenclature. .... 262e...53 Chestnut Soils 262e 224 "Western" Brown Forest Soils 225 Regosol Soils . . 262e. 262e......56 Solonetz Soils 262e.....57 Halomorphic Soils 262e 228 Hydromorphic Soils 262e... 229 Soil Association Map 262e 229 KEY TO SOIL SERIES 262e61 - 63 SOIL SERIES AND MAPPING UNIT DESCRIPTIONS 134 ~ 254 APPENDIX 1955 - 297 Soil Series and mapping unit index. 2620. . . . 255 Glossary of terms 263f 262e. . . . 272 Table of soil analyses (Oregon State College)... 1989 Table of irrigation water quality (Oregon State College) 1990 Table of conductivity and reaction. . . . 1991 Table of resistance of saturated paste 262e296 Close

• 54. [Article] Diagnostic congruence: a study on presentation of clinical information to parents and recall

  The present study was an investigation of recall following presentation of diagnostic information. The setting was the Crippled Children's Division of the University of Oregon Medical School. The purpose ...

  Citation × Citation Citation Abstract Copy Title: Diagnostic congruence: a study on presentation of clinical information to parents and recall Author: Maier, Miriam Rae Year: 1972 The present study was an investigation of recall following presentation of diagnostic information. The setting was the Crippled Children's Division of the University of Oregon Medical School. The purpose of the study was to test the hypothesis that one session conferencing imparting diagnostic information to parents of handicapped children reduces recall. Additionally, it was hypothesized that multi-discipline conferencing is related to greater diagnostic recall than single discipline conferencing. The sample was made up of 20 parent units whose children were evaluated at the Crippled Children's Division for suspected Cerebral Palsy and/or Mental Retardation. There were ten families from the Cerebral Palsy Clinic and ten from the Mental Retardation Clinic. Three comparisons were made: (1) The amount of information presented at the staffing session was the baseline against which the amount of information imparted at the parent conference was compared. (2) The amount of information imparted at the parent conference was compared with the amount of information that was recalled six weeks later at the follow up interview. (3) The amount of information recalled at the time of the follow up interview was compared with the staffing information in order to determine the loss of diagnostic information. The results supported the hypotheses. Diagnostic congruence was by far, more the exception than the rule Implications suggest that additional follow up services are necessary. Title: Diagnostic congruence: a study on presentation of clinical information to parents and recall Author: Maier, Miriam Rae Year: 1972 The present study was an investigation of recall following presentation of diagnostic information. The setting was the Crippled Children's Division of the University of Oregon Medical School. The purpose of the study was to test the hypothesis that one session conferencing imparting diagnostic information to parents of handicapped children reduces recall. Additionally, it was hypothesized that multi-discipline conferencing is related to greater diagnostic recall than single discipline conferencing. The sample was made up of 20 parent units whose children were evaluated at the Crippled Children's Division for suspected Cerebral Palsy and/or Mental Retardation. There were ten families from the Cerebral Palsy Clinic and ten from the Mental Retardation Clinic. Three comparisons were made: (1) The amount of information presented at the staffing session was the baseline against which the amount of information imparted at the parent conference was compared. (2) The amount of information imparted at the parent conference was compared with the amount of information that was recalled six weeks later at the follow up interview. (3) The amount of information recalled at the time of the follow up interview was compared with the staffing information in order to determine the loss of diagnostic information. The results supported the hypotheses. Diagnostic congruence was by far, more the exception than the rule Implications suggest that additional follow up services are necessary. Close

• 55. [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

• 56. [Article] Construction of a SNP and SSR linkage map in autotetraploid blueberry using genotyping by sequencing

  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 Springer ...

  Citation × Citation Citation Abstract Copy Title: Construction of a SNP and SSR linkage map in autotetraploid blueberry using genotyping by sequencing Author: Hackett, Christine A., Buck, Emily, Wiedow, Claudia, Wheeler, Edmund J., Bassil, Nahla V., Brown, Allan, Poland, Jesse A., Olmstead, James W., Jorgensen, Linzi, McCallum, Susan, Rowland, Lisa J., Hancock, James F., Graham, Julie, Vining, Kelly, Jackson, Eric 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 Springer and can be found at: http://link.springer.com/journal/11032 Title: Construction of a SNP and SSR linkage map in autotetraploid blueberry using genotyping by sequencing Author: Hackett, Christine A., Buck, Emily, Wiedow, Claudia, Wheeler, Edmund J., Bassil, Nahla V., Brown, Allan, Poland, Jesse A., Olmstead, James W., Jorgensen, Linzi, McCallum, Susan, Rowland, Lisa J., Hancock, James F., Graham, Julie, Vining, Kelly, Jackson, Eric 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 Springer and can be found at: http://link.springer.com/journal/11032 Close

• 57. [Article] Sex-determining chromosomes and sexual dimorphism: insights from genetic mapping of sex expression in a natural hybrid Fragaria ×ananassa subsp. cuneifolia

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.ht...

  Citation × Citation Citation Abstract Copy Title: Sex-determining chromosomes and sexual dimorphism: insights from genetic mapping of sex expression in a natural hybrid Fragaria ×ananassa subsp. cuneifolia Author: Liston, Aaron, Ashman, Tia-Lynn, Govindarajulu, Rajanikanth This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. Title: Sex-determining chromosomes and sexual dimorphism: insights from genetic mapping of sex expression in a natural hybrid Fragaria ×ananassa subsp. cuneifolia Author: Liston, Aaron, Ashman, Tia-Lynn, Govindarajulu, Rajanikanth This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. Close

• 58. [Article] Bioclimatic, ecological, and phenotypic intermediacy and high genetic admixture in a natural hybrid of octoploid strawberries

  This is the publisher’s final pdf. The published article is copyrighted by Botanical Society of America and can be found at: http://www.botany.org/.

  Citation × Citation Citation Abstract Copy Title: Bioclimatic, ecological, and phenotypic intermediacy and high genetic admixture in a natural hybrid of octoploid strawberries Author: Ashnam, Tia-Lynn, Liston, Aaron, Falk, Stacey, Govindarajulu, Rajanikanth, Parks, Matthew, Salamone, Isabella This is the publisher’s final pdf. The published article is copyrighted by Botanical Society of America and can be found at: http://www.botany.org/. Title: Bioclimatic, ecological, and phenotypic intermediacy and high genetic admixture in a natural hybrid of octoploid strawberries Author: Ashnam, Tia-Lynn, Liston, Aaron, Falk, Stacey, Govindarajulu, Rajanikanth, Parks, Matthew, Salamone, Isabella This is the publisher’s final pdf. The published article is copyrighted by Botanical Society of America and can be found at: http://www.botany.org/. Close

• 59. [Article] Single cross progeny evaluation in tall fescue, Festuca arundinacea, Schreb

  All possible single crosses from three different maturity groups of 27 selected parental genotypes of tall fescue were established in a randomized block experiment to be evaluated in 1962 for five agronomic ...

  Citation × Citation Citation Abstract Copy Title: Single cross progeny evaluation in tall fescue, Festuca arundinacea, Schreb Author: Cáceres, Oscar All possible single crosses from three different maturity groups of 27 selected parental genotypes of tall fescue were established in a randomized block experiment to be evaluated in 1962 for five agronomic characters: height, width and maturity per plant; self -seed yield per plant; and forage yield per plant. For each character, general and specific combining ability effects, relationship among these characters and heritability estimates based on mean square expectations were obtained. Results of this study indicate that genetic diversity present in the original parental population resulted in significant differences among maturity groups for the characters measured, with the exception of self-seed yield. The variability within each group was small and significant only for maturity and self-seed yield in the intermediate group and for height and maturity in the late group, indicating that the progenies were quite uniform for the other characters. Significant correlation coefficients were noted between forage yield with height and width of the plant. This significant association was observed in all three maturity groups. Estimates of heritability in narrow sense for maturity and self-seed yield in the intermediate maturity group were 0.19 and 0.46, respectively. With the preponderance of additive gene effects for self-seed yield, the value of breeding material for this character may be indicated early in a breeding program. Title: Single cross progeny evaluation in tall fescue, Festuca arundinacea, Schreb Author: Cáceres, Oscar All possible single crosses from three different maturity groups of 27 selected parental genotypes of tall fescue were established in a randomized block experiment to be evaluated in 1962 for five agronomic characters: height, width and maturity per plant; self -seed yield per plant; and forage yield per plant. For each character, general and specific combining ability effects, relationship among these characters and heritability estimates based on mean square expectations were obtained. Results of this study indicate that genetic diversity present in the original parental population resulted in significant differences among maturity groups for the characters measured, with the exception of self-seed yield. The variability within each group was small and significant only for maturity and self-seed yield in the intermediate group and for height and maturity in the late group, indicating that the progenies were quite uniform for the other characters. Significant correlation coefficients were noted between forage yield with height and width of the plant. This significant association was observed in all three maturity groups. Estimates of heritability in narrow sense for maturity and self-seed yield in the intermediate maturity group were 0.19 and 0.46, respectively. With the preponderance of additive gene effects for self-seed yield, the value of breeding material for this character may be indicated early in a breeding program. Close

• 60. [Article] Methods of evaluation, effects of intermating and results of one cycle of S₁ family recurrent selection in barley

  The focus of this study was to determine if S₁ family recurrent selection might be successfully used for barley improvement. Objectives were: 1) to identify suitable methods of evaluating grain yield in ...

  Citation × Citation Citation Abstract Copy Title: Methods of evaluation, effects of intermating and results of one cycle of S₁ family recurrent selection in barley Author: Mareck, James The focus of this study was to determine if S₁ family recurrent selection might be successfully used for barley improvement. Objectives were: 1) to identify suitable methods of evaluating grain yield in small plots, 2) to study the effects of intermating on mean values and variances of selected agronomic characters, and 3) to evaluate the response to one cycle of S₁ family selection for grain yield. Genetic materials included parents, random F₃ lines from four single cross populations, and random S₁ lines from the Cycle 0 (C-0) population which was developed by intermating the four single crosses for two generations. Heading date, plant height, and grain yield were measured on F₃ and S₁ lines grown in unreplicated small (0.7 m²) two row plots in two locations in 1979. The same traits were measured on bulk progenies of F₃ and S₁ lines grown in unreplicated large (6.0 m²) plots in three locations in 1980. Moving mean technique, which uses the mean grain yield of a number of adjacent plots as a covariable in an analysis of covariance, improved the precision of yield trials. Error mean square of replicated parents was reduced between 0 and 80 percent at different experimental sites, depending on the magnitude of field variation. Comparison of grain yield of parents grown in both large and small plots in the same year-location indicated that grain yield in small plots was affected by competition effects associated with plant height. Additional evidence for the inaccuracy of small plot yield data was supplied by the higher positive correlation between grain yield and plant height in small plots as compared to large plots. Breakup of favorably interacting associations of alleles by intermating was studied by comparing the mean of the four single crosses with the mean of the C-0 population. Two generations of intermating did not affect the mean values for plant height or grain yield, however the C-0 population headed significantly earlier due to the effect of rapid generation advancement in the intermating process. Two generations of intermating increased genetic variance for heading date and plant height, but no effect could be detected for grain yield. While some of the estimates of genetic variance for grain yield were negative, most were small and non-significant. Lack of genetic variation for grain yield is believed to be due to common parentage of the genetic materials in this study. Response to selection for grain yield was evaluated with Cycle 1 (C-1) S₁ lines developed by intermating the highest yielding 10% of C-0 S₁ lines. The C-1 population was significantly higher yielding than parents and significantly taller than parents and the C-0 population. Since little genetic variation for grain yield was found in this study, the response to selection for grain yield shown in small plot tests is believed to be a manifestation of competition effects associated with the increased plant height of the C-1 population. Successful S₁ family recurrent selection in barley may require the development of populations with greater genetic variation for grain yield. If populations with more diverse parentage and greater genetic variability are developed, then S₁ family selection in concert with improved field plot techniques may result in continued grain yield improvement in barley. Title: Methods of evaluation, effects of intermating and results of one cycle of S₁ family recurrent selection in barley Author: Mareck, James The focus of this study was to determine if S₁ family recurrent selection might be successfully used for barley improvement. Objectives were: 1) to identify suitable methods of evaluating grain yield in small plots, 2) to study the effects of intermating on mean values and variances of selected agronomic characters, and 3) to evaluate the response to one cycle of S₁ family selection for grain yield. Genetic materials included parents, random F₃ lines from four single cross populations, and random S₁ lines from the Cycle 0 (C-0) population which was developed by intermating the four single crosses for two generations. Heading date, plant height, and grain yield were measured on F₃ and S₁ lines grown in unreplicated small (0.7 m²) two row plots in two locations in 1979. The same traits were measured on bulk progenies of F₃ and S₁ lines grown in unreplicated large (6.0 m²) plots in three locations in 1980. Moving mean technique, which uses the mean grain yield of a number of adjacent plots as a covariable in an analysis of covariance, improved the precision of yield trials. Error mean square of replicated parents was reduced between 0 and 80 percent at different experimental sites, depending on the magnitude of field variation. Comparison of grain yield of parents grown in both large and small plots in the same year-location indicated that grain yield in small plots was affected by competition effects associated with plant height. Additional evidence for the inaccuracy of small plot yield data was supplied by the higher positive correlation between grain yield and plant height in small plots as compared to large plots. Breakup of favorably interacting associations of alleles by intermating was studied by comparing the mean of the four single crosses with the mean of the C-0 population. Two generations of intermating did not affect the mean values for plant height or grain yield, however the C-0 population headed significantly earlier due to the effect of rapid generation advancement in the intermating process. Two generations of intermating increased genetic variance for heading date and plant height, but no effect could be detected for grain yield. While some of the estimates of genetic variance for grain yield were negative, most were small and non-significant. Lack of genetic variation for grain yield is believed to be due to common parentage of the genetic materials in this study. Response to selection for grain yield was evaluated with Cycle 1 (C-1) S₁ lines developed by intermating the highest yielding 10% of C-0 S₁ lines. The C-1 population was significantly higher yielding than parents and significantly taller than parents and the C-0 population. Since little genetic variation for grain yield was found in this study, the response to selection for grain yield shown in small plot tests is believed to be a manifestation of competition effects associated with the increased plant height of the C-1 population. Successful S₁ family recurrent selection in barley may require the development of populations with greater genetic variation for grain yield. If populations with more diverse parentage and greater genetic variability are developed, then S₁ family selection in concert with improved field plot techniques may result in continued grain yield improvement in barley. Close