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• 51. [Article] Apoplastic distribution of atrazine and glyphosate in intact sunflower leaves

  Apoplastic distribution patterns of atrazine [2-chloro-4-(ethylamino)- 6-(isopropylamino)-s-triazine], glyphosate [N-(phosphonomethyl)- glycine], the naturally occurring apoplastic leaf solutes, and the ...

  Citation × Citation Citation Abstract Copy Title: Apoplastic distribution of atrazine and glyphosate in intact sunflower leaves Author: Jachetta, John Joseph Apoplastic distribution patterns of atrazine [2-chloro-4-(ethylamino)- 6-(isopropylamino)-s-triazine], glyphosate [N-(phosphonomethyl)- glycine], the naturally occurring apoplastic leaf solutes, and the apoplastic dye PTS (trisodium 3-hydroxy-5,8,10-pyrenetrisulfonate) were compared. Aliquots of sap were expressed from intact sunflower leaves in a pressure chamber over intervals of 0.2 to 0.4 bars. Three distinct fractions were detected in the expressed sap volume; these were tentatively identified as a petiole-midrib fraction, a minor vein-cell wall fraction, and a third fraction comprised of a decreasing minor vein-cell wall fraction and an increasing fraction of membrane-filtered cell sap. Atrazine and the naturally occurring apoplastic solutes were in a slightly higher concentration in the petiole-midrib fraction than in the minor vein-cell wall fraction. The concentration of apoplastic solutes in the third fraction was decreased with each increment of pressure to a value close to deionized water. The concentration of atrazine in the third fraction was the same as the second fraction, indicating that the plasmalemma was not a significant barrier to atrazine movement. The apoplastic distribution of PTS and glyphosate were very similar to each other, showing a marked accumulation in the minor vein-cell wall fraction. Both compounds were diluted with each successive pressure increment to a low value in the third fraction, indicating a resistance to movement into or out of the symplast. The total concentration of atrazine in the apoplast was much lower than glyphosate. Both compounds were in similar concentrations in the symplast. The apparent octanol:water partitioning coefficient for atrazine and glyphosate was determined. These values were comparable to the quotients of the symplastic and apoplastic concentrations for both atrazine and glyphosate. It was suggested that the polar nature and high water solubility of glyphosate were responsible for its slower rate of penetration into the symplast and resulting accumulation in the apoplast. These results support the intermediate permeability hypothesis; that compounds which display the apoplastic transport pattern are freely mobile between the apoplast and symplast. Compounds which are not weak acids and exhibit the symplastic transport pattern penetrate the. symplast slowly, but once absorbed, are retained for long-distance transport. Title: Apoplastic distribution of atrazine and glyphosate in intact sunflower leaves Author: Jachetta, John Joseph Apoplastic distribution patterns of atrazine [2-chloro-4-(ethylamino)- 6-(isopropylamino)-s-triazine], glyphosate [N-(phosphonomethyl)- glycine], the naturally occurring apoplastic leaf solutes, and the apoplastic dye PTS (trisodium 3-hydroxy-5,8,10-pyrenetrisulfonate) were compared. Aliquots of sap were expressed from intact sunflower leaves in a pressure chamber over intervals of 0.2 to 0.4 bars. Three distinct fractions were detected in the expressed sap volume; these were tentatively identified as a petiole-midrib fraction, a minor vein-cell wall fraction, and a third fraction comprised of a decreasing minor vein-cell wall fraction and an increasing fraction of membrane-filtered cell sap. Atrazine and the naturally occurring apoplastic solutes were in a slightly higher concentration in the petiole-midrib fraction than in the minor vein-cell wall fraction. The concentration of apoplastic solutes in the third fraction was decreased with each increment of pressure to a value close to deionized water. The concentration of atrazine in the third fraction was the same as the second fraction, indicating that the plasmalemma was not a significant barrier to atrazine movement. The apoplastic distribution of PTS and glyphosate were very similar to each other, showing a marked accumulation in the minor vein-cell wall fraction. Both compounds were diluted with each successive pressure increment to a low value in the third fraction, indicating a resistance to movement into or out of the symplast. The total concentration of atrazine in the apoplast was much lower than glyphosate. Both compounds were in similar concentrations in the symplast. The apparent octanol:water partitioning coefficient for atrazine and glyphosate was determined. These values were comparable to the quotients of the symplastic and apoplastic concentrations for both atrazine and glyphosate. It was suggested that the polar nature and high water solubility of glyphosate were responsible for its slower rate of penetration into the symplast and resulting accumulation in the apoplast. These results support the intermediate permeability hypothesis; that compounds which display the apoplastic transport pattern are freely mobile between the apoplast and symplast. Compounds which are not weak acids and exhibit the symplastic transport pattern penetrate the. symplast slowly, but once absorbed, are retained for long-distance transport. Close

• 52. [Article] Reservoir Water Re-allocation and Community Welfare

  Financial support from the QUT Business School and the FRDC (Project 2008 ⁄ 306) is gratefully acknowledged.

  Citation × Citation Citation Abstract Copy Title: Reservoir Water Re-allocation and Community Welfare Author: Wilson, Clevo, Kularatne, Mohottala G, Robinson, Tom, Pascoe, Sean Financial support from the QUT Business School and the FRDC (Project 2008 ⁄ 306) is gratefully acknowledged. Title: Reservoir Water Re-allocation and Community Welfare Author: Wilson, Clevo, Kularatne, Mohottala G, Robinson, Tom, Pascoe, Sean Financial support from the QUT Business School and the FRDC (Project 2008 ⁄ 306) is gratefully acknowledged. Close

• 53. [Article] Performance of cultivars, hybrids and composites of winter wheat (Triticum aestivum L. em Thell) grown at three locations

  The objective of this study was to compare three genetically different groups of winter wheat for their grain yield. Experimental material consisted of parental lines grown in pure stands, hybrids, and 1:1 ...

  Citation × Citation Citation Abstract Copy Title: Performance of cultivars, hybrids and composites of winter wheat (Triticum aestivum L. em Thell) grown at three locations Author: Verges, Ruben P. The objective of this study was to compare three genetically different groups of winter wheat for their grain yield. Experimental material consisted of parental lines grown in pure stands, hybrids, and 1:1 mixtures of the parental combinations. Three sites were employed to evaluate possible interactions between the different groups across locations. Phenotypic correlations among selected agronomic traits and grain yield within each group along with the expression of heterosis and heterobeltiosis in the hybrids were studied. Results of this investigation support the general conclusion reached by other investigators that hybrids and composites are not consistently superior to the best conventional cultivars of wheat for grain yield. However, at the Moro site, with the greater environmental stresses, some hybrids and composites appeared to yield more than the parental lines grown in pure stands. At Pendleton, the best environment for yield expression, the hybrids and conventional cultivars did not differ for grain yield. At this location, the best hybrids and one composite did significantly outyield the commercial cultivars Stephens, Malcolm and Hill, but not four advanced parental selections when grown in pure stands. Low to moderate values of heterosis and heterobeltiosis for grain yield were found. The degree of expression being affected by the specific growing site. Plant height and the number of kernels per spike showed relatively higher values for heterosis and heterobeltiosis over locations when compared to the other traits. Phenotypic correlations suggested that a breeding program to develop hybrid wheat should combine high number of kernels per spike with high kernel weight. The positive correlation between grain yield and plant height indicated that increases in grain yield could be obtained by increasing plant height if lodging did not present a problem. Title: Performance of cultivars, hybrids and composites of winter wheat (Triticum aestivum L. em Thell) grown at three locations Author: Verges, Ruben P. The objective of this study was to compare three genetically different groups of winter wheat for their grain yield. Experimental material consisted of parental lines grown in pure stands, hybrids, and 1:1 mixtures of the parental combinations. Three sites were employed to evaluate possible interactions between the different groups across locations. Phenotypic correlations among selected agronomic traits and grain yield within each group along with the expression of heterosis and heterobeltiosis in the hybrids were studied. Results of this investigation support the general conclusion reached by other investigators that hybrids and composites are not consistently superior to the best conventional cultivars of wheat for grain yield. However, at the Moro site, with the greater environmental stresses, some hybrids and composites appeared to yield more than the parental lines grown in pure stands. At Pendleton, the best environment for yield expression, the hybrids and conventional cultivars did not differ for grain yield. At this location, the best hybrids and one composite did significantly outyield the commercial cultivars Stephens, Malcolm and Hill, but not four advanced parental selections when grown in pure stands. Low to moderate values of heterosis and heterobeltiosis for grain yield were found. The degree of expression being affected by the specific growing site. Plant height and the number of kernels per spike showed relatively higher values for heterosis and heterobeltiosis over locations when compared to the other traits. Phenotypic correlations suggested that a breeding program to develop hybrid wheat should combine high number of kernels per spike with high kernel weight. The positive correlation between grain yield and plant height indicated that increases in grain yield could be obtained by increasing plant height if lodging did not present a problem. Close

• 54. [Article] Effects of value self-confrontation on values and academic performance of undergraduates

  This study investigated the following question: If one wants to be a good student and then compares his/her own values with those of good students, will he/she shift values immediately to resemble those ...

  Citation × Citation Citation Abstract Copy Title: Effects of value self-confrontation on values and academic performance of undergraduates Author: Seyfarth, Leonard H. This study investigated the following question: If one wants to be a good student and then compares his/her own values with those of good students, will he/she shift values immediately to resemble those of good students, and later improve academic performance? The investigator drew a sample of 237 volunteers of both sexes from a large general psychology class in a land grant university to provide data. A modified two-group pretest-posttest control group design (Campbell & Stanley, 1966) was utilized. Early in the term, groups of students were administered a three-part questionnaire. Part One, the values pretest, consisted of Rokeach's Value Survey, form E (1976, 1973). Part Two was the high or low level of value self-confrontation treatment. High treatment students (a) saw themselves as good students, and (b) compared their own values with those of previously measured good students in the course. Low treatment students (a) saw themselves as unlike high school students, and (b) compared their own values with good-student values misleadingly labelled as those of high school students. Hence, the two treatments differed only in the mind-set of the students toward the source of the comparison values. Part Three consisted of the immediate values posttest and demographic questions. The academic performance measures were the most recent GPA, and regular midterm and final examinations. The analysis was based on two values which historically had best discriminated between good and mediocre students, being self-controlled (important for good students), and pleasure (less important for good students). Analysis consisted of (a) median test using chi square on the posttest value rankings, and (b) one-way analyses of variance on midterm and final examination scores. For high treatment students, the predicted increase in the importance of being self-controlled occurred, but the predicted decline in the importance of pleasure did not. The predicted improvement in academic performance occurred on the final examination, but not on the midterm. Findings tended to support Rokeach's (1973) concentric, cognitive consistency theory of value and behavior change, and have implications for a more firmly grounded model of values education. Title: Effects of value self-confrontation on values and academic performance of undergraduates Author: Seyfarth, Leonard H. This study investigated the following question: If one wants to be a good student and then compares his/her own values with those of good students, will he/she shift values immediately to resemble those of good students, and later improve academic performance? The investigator drew a sample of 237 volunteers of both sexes from a large general psychology class in a land grant university to provide data. A modified two-group pretest-posttest control group design (Campbell & Stanley, 1966) was utilized. Early in the term, groups of students were administered a three-part questionnaire. Part One, the values pretest, consisted of Rokeach's Value Survey, form E (1976, 1973). Part Two was the high or low level of value self-confrontation treatment. High treatment students (a) saw themselves as good students, and (b) compared their own values with those of previously measured good students in the course. Low treatment students (a) saw themselves as unlike high school students, and (b) compared their own values with good-student values misleadingly labelled as those of high school students. Hence, the two treatments differed only in the mind-set of the students toward the source of the comparison values. Part Three consisted of the immediate values posttest and demographic questions. The academic performance measures were the most recent GPA, and regular midterm and final examinations. The analysis was based on two values which historically had best discriminated between good and mediocre students, being self-controlled (important for good students), and pleasure (less important for good students). Analysis consisted of (a) median test using chi square on the posttest value rankings, and (b) one-way analyses of variance on midterm and final examination scores. For high treatment students, the predicted increase in the importance of being self-controlled occurred, but the predicted decline in the importance of pleasure did not. The predicted improvement in academic performance occurred on the final examination, but not on the midterm. Findings tended to support Rokeach's (1973) concentric, cognitive consistency theory of value and behavior change, and have implications for a more firmly grounded model of values education. Close

• 55. [Article] Two Studies Addressing Practical Needs of Wheat Farmers, Processors, and Breeders : Changes in Falling Number and Alpha-amylase During Grain Storage, and Improved Predictions of Wheat-flour Dough Properties

  Wheat (Triticum aestivum) is a globally traded staple food crop. The diverse and pleasing nature of wheat-derived products is a result of the complex interactions of the polymeric components from the wheat ...

  Citation × Citation Citation Abstract Copy Title: Two Studies Addressing Practical Needs of Wheat Farmers, Processors, and Breeders : Changes in Falling Number and Alpha-amylase During Grain Storage, and Improved Predictions of Wheat-flour Dough Properties Author: Adams, Mike R. Wheat (Triticum aestivum) is a globally traded staple food crop. The diverse and pleasing nature of wheat-derived products is a result of the complex interactions of the polymeric components from the wheat endosperm. Changes in the functionality of these polymeric components, as a result of changes in growing conditions or different genetics, impacts market price and end-product quality and directly affects farmers and processors. Wheat is of particular economic importance to the U.S. Pacific Northwest and, specifically, to the state of Oregon. Providing quality wheat for export is paramount to the survival of the Oregon wheat industry. This dissertation focuses on wheat quality from the perspective of serving the practical needs of farmers, processors, and wheat breeders. The first study, split into two portions, concerns pre-harvest sprouting (PHS) and grain storage. PHS increases alpha amylase (αA) activity in wheat, which, in excess, reduces wheat end-product quality. Falling Number (FN) is the primary test used by industry to gauge PHS damage in wheats. Direct measurement of αA activity is the fundamental frame of reference. The objective of these studies was to determine if FN and αA activity of wheat samples changed during storage and if changes were a function of storage time, storage temperature, and degree of PHS damage. Samples from three Idaho locations were used. These captured a wide range of PHS degree, and therefore, wide ranges of FN values and αA activities. Samples were subdivided and stored at -20°C, +20°C, and +40°C. Low FN values and high αA activities were observed in soft wheats from locations that had rain events prior to harvest. Overall, FN and αA activity had the curvilinear relationship expected from the literature, indicating the validity of the sample set with regard to the FN/αA relationship. Changes in FN and αA activity were observed over a 90 day period of grain storage. FN differed between growing environments, wheat varieties, and storage temperatures. αA activity also differed between growing environments and wheat varieties, but not between storage temperatures. Highest rates of increase in FN were observed in hard wheats with high initial (day 0) FN values. Lowest rates of increase in FN were observed in soft wheats with low day 0 FN values. This contrasted with the changes that occurred in αA activity. Decreases in αA activity over storage time were most prevalent in soft wheats, particularly sprouted soft wheats (i.e. those with day 0 αA activities > 0.1 Ceralpha Units: CU). There were small decreases in αA activity in hard wheats but the distinction between high and low αA activity samples was not as evident as in the soft wheats because the vast majority of hard wheat samples tested had αA activities < 0.1 CU. Decreases in αA activity were in general not associated with corresponding increases in FN values over grain storage time. Increases in FN values occurred at a higher rates as storage temperature increased, particularly in hard wheats with high day 0 FN. Grain storage was successful as a way to raise FN values to > 300 s in very few cases. Storage was not effective in decreasing αA activity from > 0.1 CU to < 0.1 CU. Increases in FN over storage time for the hard wheats significantly differed between locations. However, decreases in αA activities over storage time for the hard wheats were not significantly different between locations. This again highlights a lack of correspondence between increased FN and decreased αA activity, suggesting that these two factors are somewhat decoupled when looking at changes in stored grain. Temperature-induced gluten crosslinking was explored as possible explanation for drastic increases in unsprouted hard wheat FN observed in samples from one location. Total polymeric protein (TPP) content was assessed at the end of the study for unsprouted hard wheats stored at +40°C and -20°C as well as sprouted hard wheats from stored at -20°C. TPP content was assessed as % large unextractable polymeric proteins (%LUPP) and % total unextractable polymeric proteins (%TUPP) using size exclusion high performance liquid chromatography (HPSEC). TPP content was not significantly different between storage temperatures for wheat varieties from the same location. %TUPP, but not % LUPP, was significantly lower in wheat varieties affected by PHS. Changes in FN at high storage temperature were not likely due to increased protein crosslinking. The second study aimed to validate the use of a rapid method for predicting dough strength at early generations in hard wheat breeding programs. Early generation quality screening improves breeding program efficiency. Hard wheats are used to make leavened bread products. The gluten proteins, particularly high molecular weight glutenin subunits (HMW-GS), form large, ramifying networks called the glutenin macropolymer (GMP). High GMP content is associated with increased dough strength and bread quality. Genetic differences in HMW-GS, and by inference, GMP, are responsible for differing dough properties between varieties. The Mixograph is used to measure dough mixing properties and predict end-product quality in breeding programs. GMP can also be measured as total polymeric protein (TPP) via HPSEC. The Solvent Retention Capacity (SRC) test has been proposed to predict hard wheat quality, specifically lactic acid SRC (LASRC). The objectives of this research were to provide preliminary information on the usefulness of using LASRC, on its own, to predict dough mixing properties, specifically as applied to early generation screening in a wheat breeding program, and to assess the relationship between LASRC and TPP. Wheat samples were categorized by flour protein concentration (FPC). Mixograph analysis was used as the baseline for dough properties and was analyzed both by eye and by the proprietary Mixsmart software. TPP content was assessed as %LUPP and %%TUPP. As a result of redundancy between the two TPP measures, only %LUPP was used for statistical analysis. Dough mixing parameters were slightly better correlated with LASRC than %LUPP. Correlations between LASRC, %LUPP, and dough mixing parameters were different between FPC categories, particularly in low FPC samples. A strict cutoff of 115% LASRC effectively screened out the bottom 10% of low quality hard wheats but retained a nearly equal amount of low quality hard wheats that would have been screened out by mixograph analysis. LASRC and %LUPP are not likely to be effective predictors of dough properties, but may have some value to screen for hard wheat quality in the early generations of a wheat breeding cycle. Title: Two Studies Addressing Practical Needs of Wheat Farmers, Processors, and Breeders : Changes in Falling Number and Alpha-amylase During Grain Storage, and Improved Predictions of Wheat-flour Dough Properties Author: Adams, Mike R. Wheat (Triticum aestivum) is a globally traded staple food crop. The diverse and pleasing nature of wheat-derived products is a result of the complex interactions of the polymeric components from the wheat endosperm. Changes in the functionality of these polymeric components, as a result of changes in growing conditions or different genetics, impacts market price and end-product quality and directly affects farmers and processors. Wheat is of particular economic importance to the U.S. Pacific Northwest and, specifically, to the state of Oregon. Providing quality wheat for export is paramount to the survival of the Oregon wheat industry. This dissertation focuses on wheat quality from the perspective of serving the practical needs of farmers, processors, and wheat breeders. The first study, split into two portions, concerns pre-harvest sprouting (PHS) and grain storage. PHS increases alpha amylase (αA) activity in wheat, which, in excess, reduces wheat end-product quality. Falling Number (FN) is the primary test used by industry to gauge PHS damage in wheats. Direct measurement of αA activity is the fundamental frame of reference. The objective of these studies was to determine if FN and αA activity of wheat samples changed during storage and if changes were a function of storage time, storage temperature, and degree of PHS damage. Samples from three Idaho locations were used. These captured a wide range of PHS degree, and therefore, wide ranges of FN values and αA activities. Samples were subdivided and stored at -20°C, +20°C, and +40°C. Low FN values and high αA activities were observed in soft wheats from locations that had rain events prior to harvest. Overall, FN and αA activity had the curvilinear relationship expected from the literature, indicating the validity of the sample set with regard to the FN/αA relationship. Changes in FN and αA activity were observed over a 90 day period of grain storage. FN differed between growing environments, wheat varieties, and storage temperatures. αA activity also differed between growing environments and wheat varieties, but not between storage temperatures. Highest rates of increase in FN were observed in hard wheats with high initial (day 0) FN values. Lowest rates of increase in FN were observed in soft wheats with low day 0 FN values. This contrasted with the changes that occurred in αA activity. Decreases in αA activity over storage time were most prevalent in soft wheats, particularly sprouted soft wheats (i.e. those with day 0 αA activities > 0.1 Ceralpha Units: CU). There were small decreases in αA activity in hard wheats but the distinction between high and low αA activity samples was not as evident as in the soft wheats because the vast majority of hard wheat samples tested had αA activities < 0.1 CU. Decreases in αA activity were in general not associated with corresponding increases in FN values over grain storage time. Increases in FN values occurred at a higher rates as storage temperature increased, particularly in hard wheats with high day 0 FN. Grain storage was successful as a way to raise FN values to > 300 s in very few cases. Storage was not effective in decreasing αA activity from > 0.1 CU to < 0.1 CU. Increases in FN over storage time for the hard wheats significantly differed between locations. However, decreases in αA activities over storage time for the hard wheats were not significantly different between locations. This again highlights a lack of correspondence between increased FN and decreased αA activity, suggesting that these two factors are somewhat decoupled when looking at changes in stored grain. Temperature-induced gluten crosslinking was explored as possible explanation for drastic increases in unsprouted hard wheat FN observed in samples from one location. Total polymeric protein (TPP) content was assessed at the end of the study for unsprouted hard wheats stored at +40°C and -20°C as well as sprouted hard wheats from stored at -20°C. TPP content was assessed as % large unextractable polymeric proteins (%LUPP) and % total unextractable polymeric proteins (%TUPP) using size exclusion high performance liquid chromatography (HPSEC). TPP content was not significantly different between storage temperatures for wheat varieties from the same location. %TUPP, but not % LUPP, was significantly lower in wheat varieties affected by PHS. Changes in FN at high storage temperature were not likely due to increased protein crosslinking. The second study aimed to validate the use of a rapid method for predicting dough strength at early generations in hard wheat breeding programs. Early generation quality screening improves breeding program efficiency. Hard wheats are used to make leavened bread products. The gluten proteins, particularly high molecular weight glutenin subunits (HMW-GS), form large, ramifying networks called the glutenin macropolymer (GMP). High GMP content is associated with increased dough strength and bread quality. Genetic differences in HMW-GS, and by inference, GMP, are responsible for differing dough properties between varieties. The Mixograph is used to measure dough mixing properties and predict end-product quality in breeding programs. GMP can also be measured as total polymeric protein (TPP) via HPSEC. The Solvent Retention Capacity (SRC) test has been proposed to predict hard wheat quality, specifically lactic acid SRC (LASRC). The objectives of this research were to provide preliminary information on the usefulness of using LASRC, on its own, to predict dough mixing properties, specifically as applied to early generation screening in a wheat breeding program, and to assess the relationship between LASRC and TPP. Wheat samples were categorized by flour protein concentration (FPC). Mixograph analysis was used as the baseline for dough properties and was analyzed both by eye and by the proprietary Mixsmart software. TPP content was assessed as %LUPP and %%TUPP. As a result of redundancy between the two TPP measures, only %LUPP was used for statistical analysis. Dough mixing parameters were slightly better correlated with LASRC than %LUPP. Correlations between LASRC, %LUPP, and dough mixing parameters were different between FPC categories, particularly in low FPC samples. A strict cutoff of 115% LASRC effectively screened out the bottom 10% of low quality hard wheats but retained a nearly equal amount of low quality hard wheats that would have been screened out by mixograph analysis. LASRC and %LUPP are not likely to be effective predictors of dough properties, but may have some value to screen for hard wheat quality in the early generations of a wheat breeding cycle. Close

• 56. [Article] Natural outcrossing in spaced planted F₂ populations and solid seeded advanced generations of wheat (Triticum aestivum L. em Thell)

  This study was conducted to investigate the possible contamination of foreign pollen at different stages of a wheat breeding program. These included spaced planted F₂ segregating populations, replicated ...

  Citation × Citation Citation Abstract Copy Title: Natural outcrossing in spaced planted F₂ populations and solid seeded advanced generations of wheat (Triticum aestivum L. em Thell) Author: Boinnet, Jerry K. K. This study was conducted to investigate the possible contamination of foreign pollen at different stages of a wheat breeding program. These included spaced planted F₂ segregating populations, replicated yield trials and seed multiplication. The experimental wheat materials consisted of four different F₂ populations, four cultivars and two experimental lines. Two genetic marker lines, Blue Hyslop and Blue Norco were used to determine the amount of possible outcrossing. The pollen of these marker lines carry genetic factors for blue aleurone color, thus the extent of outcrossing (wherever outcrossing had occurred in the experimental populations) could be immediately observed and determined during the same crop season. The mean percent outcrossing recorded was less than 1% in spaced planted F₂ populations, different replicated yield trials and seed multiplication conditions. The highest percentage of outcrossing of 5.6% was observed for a single plant in a spaced planted F₂ population. Under yield trial conditions, the highest percentage of outcrossing of 0.6% was recorded for the cultivar Hill 81 whereas the lowest value of 0.1% was recorded for experimental line SPN/AU/YMH. Under seed multiplication conditions, a sample taken at 0.5 m away from blue aleurone pollen source in low density planting had a mean outcrossing value of 0.5% for the cultivar Jackmar. Pollen load of marker lines relative to that of all entries in low seeding rate was high, consequently, the low seeding rate had higher levels of outcrossing than the high seeding rate. No significant effect on outcrossing was observed for Seeding rate x Entry interaction. However, effects of entry and sampling distance on outcrossing were significant. As sampling distance increased from the blue aleurone pollen source, the level of outcrossing decreased. Low positive correlation of 0.12 and 0.14 existed between outcrossing and plant height and tillers per linear meter respectively. Correlation of 0.70 was found between natural outcrossing and wind velocity. Results of this study suggest that outcrossing can occur in all stages of a breeding program. The results also indicate that an isolation distance of 2 m established for multiplication of registered and certified seed in the certification program of Oregon State University might not be adequate especially for such cuitivars as Jackmar and Hill 81. Furthermore, the level of outcrossing detected was high enough to distort and perhaps alter the genetic identity and integrity of the breeding material. A similar problem will exist if care is not exercised when growing valuable wheat germplasm in various collection centers. Title: Natural outcrossing in spaced planted F₂ populations and solid seeded advanced generations of wheat (Triticum aestivum L. em Thell) Author: Boinnet, Jerry K. K. This study was conducted to investigate the possible contamination of foreign pollen at different stages of a wheat breeding program. These included spaced planted F₂ segregating populations, replicated yield trials and seed multiplication. The experimental wheat materials consisted of four different F₂ populations, four cultivars and two experimental lines. Two genetic marker lines, Blue Hyslop and Blue Norco were used to determine the amount of possible outcrossing. The pollen of these marker lines carry genetic factors for blue aleurone color, thus the extent of outcrossing (wherever outcrossing had occurred in the experimental populations) could be immediately observed and determined during the same crop season. The mean percent outcrossing recorded was less than 1% in spaced planted F₂ populations, different replicated yield trials and seed multiplication conditions. The highest percentage of outcrossing of 5.6% was observed for a single plant in a spaced planted F₂ population. Under yield trial conditions, the highest percentage of outcrossing of 0.6% was recorded for the cultivar Hill 81 whereas the lowest value of 0.1% was recorded for experimental line SPN/AU/YMH. Under seed multiplication conditions, a sample taken at 0.5 m away from blue aleurone pollen source in low density planting had a mean outcrossing value of 0.5% for the cultivar Jackmar. Pollen load of marker lines relative to that of all entries in low seeding rate was high, consequently, the low seeding rate had higher levels of outcrossing than the high seeding rate. No significant effect on outcrossing was observed for Seeding rate x Entry interaction. However, effects of entry and sampling distance on outcrossing were significant. As sampling distance increased from the blue aleurone pollen source, the level of outcrossing decreased. Low positive correlation of 0.12 and 0.14 existed between outcrossing and plant height and tillers per linear meter respectively. Correlation of 0.70 was found between natural outcrossing and wind velocity. Results of this study suggest that outcrossing can occur in all stages of a breeding program. The results also indicate that an isolation distance of 2 m established for multiplication of registered and certified seed in the certification program of Oregon State University might not be adequate especially for such cuitivars as Jackmar and Hill 81. Furthermore, the level of outcrossing detected was high enough to distort and perhaps alter the genetic identity and integrity of the breeding material. A similar problem will exist if care is not exercised when growing valuable wheat germplasm in various collection centers. Close

• 57. [Article] Effect of lot size on lot uniformity in Lolium spp. seed

  Studies were conducted to determine the uniformity of three commercial seed lots of ryegrass (Lolium spp.) and the effects of lot size on lot uniformity. Individual bag-samples were taken from each seed ...

  Citation × Citation Citation Abstract Copy Title: Effect of lot size on lot uniformity in Lolium spp. seed Author: Cook, Ronald Lawrence Studies were conducted to determine the uniformity of three commercial seed lots of ryegrass (Lolium spp.) and the effects of lot size on lot uniformity. Individual bag-samples were taken from each seed lot. Factors considered were percentage purity, annual ryegrass, perennial ryegrass, weed, other crop, inert matter, and germination. Number of rattail fescue (Festuca myuros) seeds and number of orchardgrass (Dactylis glomerata) seeds in a purity sample were counted, and number of noxious weed seeds were also totaled. Uniformity in 30,000 kilogram lots was measured by an H-test, heterogeneity value, state seed law labeling tolerance tables, and by a Chi-square test for homogeneity of a binomial distribution on each sub-lot. Subdivisionsof each seed lot were examined for uniformity by use of an analysis of variance test. The analysis used within sublot variance of lot size approximately 1,500 kilograms as an acceptable level of variation and used an analysis of variance test to examine variance among sub-lots of approximate size 1,500, 3,000, 6,000, and 12,000 kilograms. The greatest potential for violation in labeling and nonuniformity in ryegrass seed lots was found in percentage perennial ryegrass and annual ryegrass factors calculated by formula from fluorescence. Changing seed lot size had no effect on lot uniformity. Reducing the lot size below the current 24,947 kilogram limit did not significantly reduce the number of violations in labeling. Fewer violations were found in high purity seed lots than in low purity seed lots. Title: Effect of lot size on lot uniformity in Lolium spp. seed Author: Cook, Ronald Lawrence Studies were conducted to determine the uniformity of three commercial seed lots of ryegrass (Lolium spp.) and the effects of lot size on lot uniformity. Individual bag-samples were taken from each seed lot. Factors considered were percentage purity, annual ryegrass, perennial ryegrass, weed, other crop, inert matter, and germination. Number of rattail fescue (Festuca myuros) seeds and number of orchardgrass (Dactylis glomerata) seeds in a purity sample were counted, and number of noxious weed seeds were also totaled. Uniformity in 30,000 kilogram lots was measured by an H-test, heterogeneity value, state seed law labeling tolerance tables, and by a Chi-square test for homogeneity of a binomial distribution on each sub-lot. Subdivisionsof each seed lot were examined for uniformity by use of an analysis of variance test. The analysis used within sublot variance of lot size approximately 1,500 kilograms as an acceptable level of variation and used an analysis of variance test to examine variance among sub-lots of approximate size 1,500, 3,000, 6,000, and 12,000 kilograms. The greatest potential for violation in labeling and nonuniformity in ryegrass seed lots was found in percentage perennial ryegrass and annual ryegrass factors calculated by formula from fluorescence. Changing seed lot size had no effect on lot uniformity. Reducing the lot size below the current 24,947 kilogram limit did not significantly reduce the number of violations in labeling. Fewer violations were found in high purity seed lots than in low purity seed lots. Close

• 58. [Article] Sexual harassment proclivity of men : relationship to values

  The sexual harassment of women by men is a social phenomenon that exists in academia as well as business and industry. It has only recently been recognized as a significant social problem. The purpose ...

  Citation × Citation Citation Abstract Copy Title: Sexual harassment proclivity of men : relationship to values Author: Olsen, Eric R. The sexual harassment of women by men is a social phenomenon that exists in academia as well as business and industry. It has only recently been recognized as a significant social problem. The purpose of this study was to determine if men who have a high proclivity toward sexual harassment differ in their ranking of personal values from men who have a low proclivity toward sexual harassment. The rationale behind the study was if there is a relationship between personal values and sexual harassment proclivity then values education and exploration may provide an intervention method to reduce sexual harassment. The sample consisted of 100 randomly selected undergraduate male students at Oregon State University. Seventy four percent of the respondents completed two surveys: the Likelihood of Sexually Harassing Scale (LSH) (Pryor, 1987) and the Rokeach Value Survey (1973). The LSH was used to identify two groups of men: those with a high proclivity toward sexual harassment and those with a low proclivity toward sexual harassment. The two groups ranking of values were then compared to determine if a significant difference existed. Data were analyzed using chi-square to test for significant differences between the two groups ranking of values and also test the significance of the phi coefficient to determine if a relationship existed between score on LSH and ranking of values. Results of the study indicated that there is a significant difference between men with a high proclivity and men with a low proclivity toward sexual harassment in their ranking on 5 of 36 values. The low proclivity group ranked equality, honest, loyal, and salvation significantly higher than the high proclivity group. The high proclivity group ranked a comfortable life significantly higher than the low proclivity group. The values ranked significantly higher by the low proclivity group are social values that denote respect for and cooperation with others. The value ranked significantly higher by the high proclivity group is a personal value that denotes a materialistic and self indulgent orientation. Values education or exploration programs that focus on equality, honesty and loyalty may help to reduce sexually harassing behavior. Title: Sexual harassment proclivity of men : relationship to values Author: Olsen, Eric R. The sexual harassment of women by men is a social phenomenon that exists in academia as well as business and industry. It has only recently been recognized as a significant social problem. The purpose of this study was to determine if men who have a high proclivity toward sexual harassment differ in their ranking of personal values from men who have a low proclivity toward sexual harassment. The rationale behind the study was if there is a relationship between personal values and sexual harassment proclivity then values education and exploration may provide an intervention method to reduce sexual harassment. The sample consisted of 100 randomly selected undergraduate male students at Oregon State University. Seventy four percent of the respondents completed two surveys: the Likelihood of Sexually Harassing Scale (LSH) (Pryor, 1987) and the Rokeach Value Survey (1973). The LSH was used to identify two groups of men: those with a high proclivity toward sexual harassment and those with a low proclivity toward sexual harassment. The two groups ranking of values were then compared to determine if a significant difference existed. Data were analyzed using chi-square to test for significant differences between the two groups ranking of values and also test the significance of the phi coefficient to determine if a relationship existed between score on LSH and ranking of values. Results of the study indicated that there is a significant difference between men with a high proclivity and men with a low proclivity toward sexual harassment in their ranking on 5 of 36 values. The low proclivity group ranked equality, honest, loyal, and salvation significantly higher than the high proclivity group. The high proclivity group ranked a comfortable life significantly higher than the low proclivity group. The values ranked significantly higher by the low proclivity group are social values that denote respect for and cooperation with others. The value ranked significantly higher by the high proclivity group is a personal value that denotes a materialistic and self indulgent orientation. Values education or exploration programs that focus on equality, honesty and loyalty may help to reduce sexually harassing behavior. Close

• 59. [Article] Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies

  Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types ...

  Citation × Citation Citation Abstract Copy Title: Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies Author: Keifer, Jarrett Alexander Year: 2014 Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types to verify this hypothesis require high spatial or spectral resolution data, or extensive ground truth information to develop training sites, none of which are freely available for much of the world. I developed a new method of crop classification based on the phenological signatures of crops extracted from multi-temporal MODIS vegetation indices. I tested and refined this method using the USDA Cropland Data Layer from Kansas, USA as a reference. I then applied the method to classify crop types for a study site in Pellegrini, Santiago Del Estero, Argentina. The results show that this method is unable to effectively separate summer crops in Pellegrini, but can differentiate summer crops and non-summer crops. Unmet assumptions about agricultural practices are primarily responsible for the ineffective summer crop classification, underlining the need for researchers to have a complete understanding of ground conditions when designing a remote sensing analysis. Title: Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies Author: Keifer, Jarrett Alexander Year: 2014 Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types to verify this hypothesis require high spatial or spectral resolution data, or extensive ground truth information to develop training sites, none of which are freely available for much of the world. I developed a new method of crop classification based on the phenological signatures of crops extracted from multi-temporal MODIS vegetation indices. I tested and refined this method using the USDA Cropland Data Layer from Kansas, USA as a reference. I then applied the method to classify crop types for a study site in Pellegrini, Santiago Del Estero, Argentina. The results show that this method is unable to effectively separate summer crops in Pellegrini, but can differentiate summer crops and non-summer crops. Unmet assumptions about agricultural practices are primarily responsible for the ineffective summer crop classification, underlining the need for researchers to have a complete understanding of ground conditions when designing a remote sensing analysis. Close

• 60. [Article] Measuring costs of sequestering carbon in forest stands with different management regimes in western Oregon

  This project was a part of larger work that compared major factors controlling patterns of carbon dynamics in two regions of the globe, the Pacific Northwest, USA and northwestern Russia. It was funded ...

  Citation × Citation Citation Abstract Copy Title: Measuring costs of sequestering carbon in forest stands with different management regimes in western Oregon Author: Zyrina, Olga A. This project was a part of larger work that compared major factors controlling patterns of carbon dynamics in two regions of the globe, the Pacific Northwest, USA and northwestern Russia. It was funded through the NASA foundation (grant # NAG5- 6242). Human economic activity is causing the release of pollutants such as carbon dioxide. The increased concentration of pollutants in the atmosphere is thought to cause greenhouse effect, in other words - the warming of the earth and lower atmosphere. Different methods are proposed to reduce concentration of greenhouse gases (GHG) in the atmosphere. Some involve development of more clean technologies. Some involve reductions in the use of fossil fuels. Another possibility is to store carbon (C) as live biomass. Plants use C for growth and development. Using forests to sequester C is one strategy for mitigating effects of GHG emissions. There are many methods in forestry to grow trees and produce wood products. Some of them include clearcutting, thinning, fertilizing, burning, and partial cutting. This project had three purposes. First, was to investigate the effect of a wide variety of silvicultural treatments on C storage and the economic value of harvested forest products. We measured economic value as soil expectation value. Second, was to use Data Envelopment Analysis to determine the efficient set of treatments, which make up the Production Possibility Frontier (PPF) in terms of C and economic value. Third, was to use the PPF to measure the marginal cost of carbon storage in moving from high SEV and relatively low C storage to lower SEV and relatively high C storage. C storage and timber harvest were simulated using the STANDCARB model for forest types common in north-western Oregon with two tree species, Douglas fir (Pseudotsuga menziesii) and Western hemlock (Tsuga heterophylla). Fifty silvicultural regimes were investigated. They included clearcutting with rotations of 50, 70, 90, 110, 130, and 150. Each of the six rotation ages had eight combinations of silvicultural treatments consisting of artificial and natural regeneration, growth enhancement (GE) and thinning. Two partial cutting regimes: group selection and single-tree selection were also used in the analysis. C storage was calculated for every output year of each model run as a sum of live, dead, and stable C. C storage for each silvicultural regime was measured as the average over five full rotations from the steady state portion of the run. The analysis showed that average C increases with rotation age from 335.99 MgC/ha with 50-year rotation with natural regeneration and thinning to 826.36 MgCIha with 150-year rotation with artificial regeneration and GE. The use of artificial regeneration compared to natural regeneration gave a 20-30 MgC/ha improvement for all regimes. The total harvest from thinning and clearcutting over the rotation period averaged for several runs varied from 505.34 m3/ha (with 50-year rotation no treatment) to 1782.24 m3/ha (with 150-year rotation with GE and thinning) The use of artificial compared to natural regeneration gave a 20-50 m3/ha increase in harvest for all regimes. SEV is the present value of net revenues from perpetually growing tree crops following the specified regime. It measures the economic value of each regime. Generally, SEV has a negative correlation with rotation length. Using a 3.5 percent real discount rate, the maximum SEV ($7904.3/hectare) was obtained from 50-year rotation with artificial regeneration, GE and thinning In contrast, SEV for 130-year rotation with artificial regeneration was only $446.68/hectare. Using Data Envelopment Analysis (OnFront software) we found that 8 of the 50 regimes investigated were efficient in their ability to store C and produce economic value. The efficient regimes included 50, 110, 130 and 150-year rotations with artificial regeneration, GE and thinning; 110, 130 and 150-year rotations with natural regeneration, GE and thinning, and the 150-year rotation with natural regeneration and GE. When regimes with GE were excluded, we found 7 efficient regimes: 50 and 150-year rotations with artificial regeneration and thinning, 50, 110, 130 and 150-year rotations with natural regeneration and thinning, and the 150-year rotation with natural regeneration. The marginal cost of C storage is the SEV lost per unit of C due to change in silvicultural regimes that results in increase of average C stored. Marginal cost analysis indicated that marginal cost values were similar for regimes with GE and without. As C storage increased, the marginal cost generally increased. The increase in C storage from 428 MgC/ha to 589 MgC/ha implied a marginal cost of $13.28IMgC. In case of increasing C storage from 683 MgC/ha to 802.7 MgC/ha, the marginal cost would increase to $32.79JMgC. Title: Measuring costs of sequestering carbon in forest stands with different management regimes in western Oregon Author: Zyrina, Olga A. This project was a part of larger work that compared major factors controlling patterns of carbon dynamics in two regions of the globe, the Pacific Northwest, USA and northwestern Russia. It was funded through the NASA foundation (grant # NAG5- 6242). Human economic activity is causing the release of pollutants such as carbon dioxide. The increased concentration of pollutants in the atmosphere is thought to cause greenhouse effect, in other words - the warming of the earth and lower atmosphere. Different methods are proposed to reduce concentration of greenhouse gases (GHG) in the atmosphere. Some involve development of more clean technologies. Some involve reductions in the use of fossil fuels. Another possibility is to store carbon (C) as live biomass. Plants use C for growth and development. Using forests to sequester C is one strategy for mitigating effects of GHG emissions. There are many methods in forestry to grow trees and produce wood products. Some of them include clearcutting, thinning, fertilizing, burning, and partial cutting. This project had three purposes. First, was to investigate the effect of a wide variety of silvicultural treatments on C storage and the economic value of harvested forest products. We measured economic value as soil expectation value. Second, was to use Data Envelopment Analysis to determine the efficient set of treatments, which make up the Production Possibility Frontier (PPF) in terms of C and economic value. Third, was to use the PPF to measure the marginal cost of carbon storage in moving from high SEV and relatively low C storage to lower SEV and relatively high C storage. C storage and timber harvest were simulated using the STANDCARB model for forest types common in north-western Oregon with two tree species, Douglas fir (Pseudotsuga menziesii) and Western hemlock (Tsuga heterophylla). Fifty silvicultural regimes were investigated. They included clearcutting with rotations of 50, 70, 90, 110, 130, and 150. Each of the six rotation ages had eight combinations of silvicultural treatments consisting of artificial and natural regeneration, growth enhancement (GE) and thinning. Two partial cutting regimes: group selection and single-tree selection were also used in the analysis. C storage was calculated for every output year of each model run as a sum of live, dead, and stable C. C storage for each silvicultural regime was measured as the average over five full rotations from the steady state portion of the run. The analysis showed that average C increases with rotation age from 335.99 MgC/ha with 50-year rotation with natural regeneration and thinning to 826.36 MgCIha with 150-year rotation with artificial regeneration and GE. The use of artificial regeneration compared to natural regeneration gave a 20-30 MgC/ha improvement for all regimes. The total harvest from thinning and clearcutting over the rotation period averaged for several runs varied from 505.34 m3/ha (with 50-year rotation no treatment) to 1782.24 m3/ha (with 150-year rotation with GE and thinning) The use of artificial compared to natural regeneration gave a 20-50 m3/ha increase in harvest for all regimes. SEV is the present value of net revenues from perpetually growing tree crops following the specified regime. It measures the economic value of each regime. Generally, SEV has a negative correlation with rotation length. Using a 3.5 percent real discount rate, the maximum SEV ($7904.3/hectare) was obtained from 50-year rotation with artificial regeneration, GE and thinning In contrast, SEV for 130-year rotation with artificial regeneration was only $446.68/hectare. Using Data Envelopment Analysis (OnFront software) we found that 8 of the 50 regimes investigated were efficient in their ability to store C and produce economic value. The efficient regimes included 50, 110, 130 and 150-year rotations with artificial regeneration, GE and thinning; 110, 130 and 150-year rotations with natural regeneration, GE and thinning, and the 150-year rotation with natural regeneration and GE. When regimes with GE were excluded, we found 7 efficient regimes: 50 and 150-year rotations with artificial regeneration and thinning, 50, 110, 130 and 150-year rotations with natural regeneration and thinning, and the 150-year rotation with natural regeneration. The marginal cost of C storage is the SEV lost per unit of C due to change in silvicultural regimes that results in increase of average C stored. Marginal cost analysis indicated that marginal cost values were similar for regimes with GE and without. As C storage increased, the marginal cost generally increased. The increase in C storage from 428 MgC/ha to 589 MgC/ha implied a marginal cost of $13.28IMgC. In case of increasing C storage from 683 MgC/ha to 802.7 MgC/ha, the marginal cost would increase to $32.79JMgC. Close