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• 81. [Article] Estimating Wholesale Demand for Live Reef Food Fish in Hong Kong

  Wholesale demand systems for live reef food fish in Hong Kong are analysed using the Linear Approximate Almost Ideal Demand System (LA/AIDS). Results suggest that price elasticities of demand are inelastic, ...

  Citation × Citation Citation Abstract Copy Title: Estimating Wholesale Demand for Live Reef Food Fish in Hong Kong Author: Petersen, Elizabeth Wholesale demand systems for live reef food fish in Hong Kong are analysed using the Linear Approximate Almost Ideal Demand System (LA/AIDS). Results suggest that price elasticities of demand are inelastic, with relatively high-valued species exhibiting greater elasticity than relatively low-valued species. Cross price elasticities are negative suggesting that different live reef fish species are complements. Live reef fish are found to be normal goods, with relatively high-valued species being less expenditure-elastic than relatively low-valued species. SARS is found to shift expenditure away from high-valued species to low-valued species. There is no evidence that Chinese New Year has a significant impact on demand. Title: Estimating Wholesale Demand for Live Reef Food Fish in Hong Kong Author: Petersen, Elizabeth Wholesale demand systems for live reef food fish in Hong Kong are analysed using the Linear Approximate Almost Ideal Demand System (LA/AIDS). Results suggest that price elasticities of demand are inelastic, with relatively high-valued species exhibiting greater elasticity than relatively low-valued species. Cross price elasticities are negative suggesting that different live reef fish species are complements. Live reef fish are found to be normal goods, with relatively high-valued species being less expenditure-elastic than relatively low-valued species. SARS is found to shift expenditure away from high-valued species to low-valued species. There is no evidence that Chinese New Year has a significant impact on demand. Close

• 82. [Image] Reclamation accomplishments, 1905-1953, Klamath Project, Oregon-California

  	SUMMARY AND CONCLUSIONS Klamath Project is a $13 million Federal investment in water resource development, About 200,000 acres are irrigated and gross crop production (has exceeded $17 million each year ...
  	Citation × Citation Citation Abstract Copy Title: Reclamation accomplishments, 1905-1953, Klamath Project, Oregon-California Author: Strantz, Maurice K. Year: 1953, 2005 SUMMARY AND CONCLUSIONS Klamath Project is a $13 million Federal investment in water resource development, About 200,000 acres are irrigated and gross crop production (has exceeded $17 million each year over the past 7 years. The Project encompasses the largest single block of irrigated land in the area and includes nearly half the three-county total irrigated area and one quarter of the cropland. Agriculture and manufacturing directly contribute half the three-county personal income and provide half the jobs. Klamath Project accounts for five-sixths of the gross income from crops, and half the total agricultural production in the three-county area. Personal income from project crops is estimated at $10.6 mil1ion in 1948. Recent crop production on the project supports directly or indirectly about $25 million in local personal income. Federal contribution for irrigation to repay costs without interest to date amounts to about $10.8 million. Annual personal income generated by project in the postwar years equals this assistance Project gross crop production of nearly $300 million over 46 years. Project farm income supports substantial portion of area retail trade and contributes to transportation and other services. Project agriculture in past 10 years increased its support to the economy and has helped offset the declines in the lumber industry. Without the project only about 50,000 irrigated acres would have been developed and the agricultural economy would have produced crops worth only about l/7th as large as at present. Reclamation development tends to maintain a stable prosperous economy in the three-county area. Title: Reclamation accomplishments, 1905-1953, Klamath Project, Oregon-California Author: Strantz, Maurice K. Year: 1953, 2005 SUMMARY AND CONCLUSIONS Klamath Project is a $13 million Federal investment in water resource development, About 200,000 acres are irrigated and gross crop production (has exceeded $17 million each year over the past 7 years. The Project encompasses the largest single block of irrigated land in the area and includes nearly half the three-county total irrigated area and one quarter of the cropland. Agriculture and manufacturing directly contribute half the three-county personal income and provide half the jobs. Klamath Project accounts for five-sixths of the gross income from crops, and half the total agricultural production in the three-county area. Personal income from project crops is estimated at $10.6 mil1ion in 1948. Recent crop production on the project supports directly or indirectly about $25 million in local personal income. Federal contribution for irrigation to repay costs without interest to date amounts to about $10.8 million. Annual personal income generated by project in the postwar years equals this assistance Project gross crop production of nearly $300 million over 46 years. Project farm income supports substantial portion of area retail trade and contributes to transportation and other services. Project agriculture in past 10 years increased its support to the economy and has helped offset the declines in the lumber industry. Without the project only about 50,000 irrigated acres would have been developed and the agricultural economy would have produced crops worth only about l/7th as large as at present. Reclamation development tends to maintain a stable prosperous economy in the three-county area. Close

• 83. [Article] Crop and tree response to planting patterns in alley cropping systems

  Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved ...

  Citation × Citation Citation Abstract Copy Title: Crop and tree response to planting patterns in alley cropping systems Author: Seiter, Stefan Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved in species interactions, three feasible alley cropping and two sweet corn monocrop planting patterns were studied in a replicated factorial experiment. Each alley cropping pattern was planted twice, with either red alder (Alnus rubra Bong) or black locust (Robinia pseudoacacia L.). The annual crop component used was sweet corn (Zea mays L.). Sweet com population was the same in all plant arrangements, except one alley cropping pattern. The monocrop control, planted at 63.5 cm row spacing, yielded highest while the lowest com yield was produced in the alley cropping system that involved alternate com and black locust rows. The highest com yield produced among alley cropping patterns surpassed the control planted at 89 cm row spacing. Com yield in planting patterns was dependent on the relative space occupied by each species. A high ratio of tree occupation was negatively correlated with com yield. Greatest pruning biomass was produced in alley cropping systems with highest tree population and greatest percentage of tree space occupation. Compared to black locust, biomass produced by red alder trees was minimal. Within alley cropping patterns of the same tree species, lower crop yield coincided with highest pruning biomass implicating trade-offs between potential soil improving effects and crop yield. Tree biomass was more strongly affected by changes in relative space occupation than com yield. Yield of individual com rows within treatments varied considerably. In alley cropping systems where several com rows were separated by double rows of trees, com rows adjacent to trees yielded significantly more than those neighboring com rows on either side. Com row position had no significant effect in monocrop or patterns where tree and com alternated. Mean yield of individual com plants decreased when both neighboring com rows and neighboring tree row were in close proximity. The approach of using a few planting patterns as experimental treatments did not permit to precisely model the relationships between single proximity factors and yield components. However, the approach permitted identification of factors contributing the most to changes in tree and crop yield and demonstrated basic trends. Title: Crop and tree response to planting patterns in alley cropping systems Author: Seiter, Stefan Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved in species interactions, three feasible alley cropping and two sweet corn monocrop planting patterns were studied in a replicated factorial experiment. Each alley cropping pattern was planted twice, with either red alder (Alnus rubra Bong) or black locust (Robinia pseudoacacia L.). The annual crop component used was sweet corn (Zea mays L.). Sweet com population was the same in all plant arrangements, except one alley cropping pattern. The monocrop control, planted at 63.5 cm row spacing, yielded highest while the lowest com yield was produced in the alley cropping system that involved alternate com and black locust rows. The highest com yield produced among alley cropping patterns surpassed the control planted at 89 cm row spacing. Com yield in planting patterns was dependent on the relative space occupied by each species. A high ratio of tree occupation was negatively correlated with com yield. Greatest pruning biomass was produced in alley cropping systems with highest tree population and greatest percentage of tree space occupation. Compared to black locust, biomass produced by red alder trees was minimal. Within alley cropping patterns of the same tree species, lower crop yield coincided with highest pruning biomass implicating trade-offs between potential soil improving effects and crop yield. Tree biomass was more strongly affected by changes in relative space occupation than com yield. Yield of individual com rows within treatments varied considerably. In alley cropping systems where several com rows were separated by double rows of trees, com rows adjacent to trees yielded significantly more than those neighboring com rows on either side. Com row position had no significant effect in monocrop or patterns where tree and com alternated. Mean yield of individual com plants decreased when both neighboring com rows and neighboring tree row were in close proximity. The approach of using a few planting patterns as experimental treatments did not permit to precisely model the relationships between single proximity factors and yield components. However, the approach permitted identification of factors contributing the most to changes in tree and crop yield and demonstrated basic trends. Close

• 84. [Article] Evaluation of popcorn cultivars as resistant rotation crops to Columbia root-knot nematode : a systems approach

  This study examined the management situation for the Columbiaroot-knot nematode (Meloidogyne chitwoodi) in potato, using an approach with systems thinking and interactive meetings. The focus of current ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of popcorn cultivars as resistant rotation crops to Columbia root-knot nematode : a systems approach Author: Cardwell, Derek This study examined the management situation for the Columbiaroot-knot nematode (Meloidogyne chitwoodi) in potato, using an approach with systems thinking and interactive meetings. The focus of current research for control of this nematode was evaluated. Control practices include crop rotation, and this study also evaluated popcorn cultivars for their potential as resistant rotation crops. Popcorn cultivars were grown in M. chitwoodi race 1 infested soil at the Hermiston Agricultural Research and Extension Center (HAREC), Hermiston, OR. Soil samples were taken soon after planting (initial) and before harvest (final), and the number of M. chitwoodi juveniles / 250 g dry soil was calculated for each sample. A reproduction index was calculated for the nematode reproduction on each cultivar: R value = initial / final population. Cultivars were categorized as good, poor- and nonhosts depending on their R values. Popcorn cultivars were also tested for their host status in the greenhouse. Plants were inoculated with approximately 5000 M. chitwoodi eggs (initial), and after 55 days, eggs were extracted from the roots (final). In the field and greenhouse tests, field corn (FC) cv Pioneer 3578 was tested as a good host check. Among cultivars tested in both the field and greenhouse, the seven with the lowest R values as % of FC 3578 were: WOC 9508 (4%), W206 (16%), WOX 9512 (23%), Robust 33-77 (30%), Robust 20-70 (38%), and WOC 9504 (42%). Cultivars more susceptible than field corn were (R values as % of FC 3578 - mean of field, greenhouse tests): W 104 (119%) and Robust 90477 (102%). Popcorn cultivars WOC 9531, WOC 9556, WOX 9528, and WOX 9511 were more resistant than field corn but still need to be also tested in the field. Cultivars with R values < 1.0 in field tests can be functional in decreasing or stabilizing nematode populations, thus increasing the effectiveness of prepotato nematicides or winter cover crops. This nematode pest situation was analyzed with use of diagrams showing interacting components of the system. This system includes people, nematodes, and potatoes. Issues and questions emerged as the situation was viewed in a systems manner. Some of these issues and questions were the foci of a Farmer-Scientist Focus Session conducted on June 28th, 1995 in Hermiston, OR. Participants included growers, researchers, and extension educators. The meeting was interactive and facilitated the expression of ideas, perspectives, and concerns of the crop rotation possibilities for controlling M. chitwoodi. The opportunities and challenges using non-host crops in potato rotations were discussed. Growers expressed desire for more agronomic information about currently available poor- and non-host cultivars. They did not emphasize a need for a more diverse selection of resistant cultivars. From the grower's perspective, the main opportunity of resistant crop rotation is the integration of suppressive winter cover crops. The main challenge is the small market size for most non-host crops. Additional interactive meetings are needed to stimulate the creation of new ideas and to refine the vision and direction of research in a cooperative manner. Title: Evaluation of popcorn cultivars as resistant rotation crops to Columbia root-knot nematode : a systems approach Author: Cardwell, Derek This study examined the management situation for the Columbiaroot-knot nematode (Meloidogyne chitwoodi) in potato, using an approach with systems thinking and interactive meetings. The focus of current research for control of this nematode was evaluated. Control practices include crop rotation, and this study also evaluated popcorn cultivars for their potential as resistant rotation crops. Popcorn cultivars were grown in M. chitwoodi race 1 infested soil at the Hermiston Agricultural Research and Extension Center (HAREC), Hermiston, OR. Soil samples were taken soon after planting (initial) and before harvest (final), and the number of M. chitwoodi juveniles / 250 g dry soil was calculated for each sample. A reproduction index was calculated for the nematode reproduction on each cultivar: R value = initial / final population. Cultivars were categorized as good, poor- and nonhosts depending on their R values. Popcorn cultivars were also tested for their host status in the greenhouse. Plants were inoculated with approximately 5000 M. chitwoodi eggs (initial), and after 55 days, eggs were extracted from the roots (final). In the field and greenhouse tests, field corn (FC) cv Pioneer 3578 was tested as a good host check. Among cultivars tested in both the field and greenhouse, the seven with the lowest R values as % of FC 3578 were: WOC 9508 (4%), W206 (16%), WOX 9512 (23%), Robust 33-77 (30%), Robust 20-70 (38%), and WOC 9504 (42%). Cultivars more susceptible than field corn were (R values as % of FC 3578 - mean of field, greenhouse tests): W 104 (119%) and Robust 90477 (102%). Popcorn cultivars WOC 9531, WOC 9556, WOX 9528, and WOX 9511 were more resistant than field corn but still need to be also tested in the field. Cultivars with R values < 1.0 in field tests can be functional in decreasing or stabilizing nematode populations, thus increasing the effectiveness of prepotato nematicides or winter cover crops. This nematode pest situation was analyzed with use of diagrams showing interacting components of the system. This system includes people, nematodes, and potatoes. Issues and questions emerged as the situation was viewed in a systems manner. Some of these issues and questions were the foci of a Farmer-Scientist Focus Session conducted on June 28th, 1995 in Hermiston, OR. Participants included growers, researchers, and extension educators. The meeting was interactive and facilitated the expression of ideas, perspectives, and concerns of the crop rotation possibilities for controlling M. chitwoodi. The opportunities and challenges using non-host crops in potato rotations were discussed. Growers expressed desire for more agronomic information about currently available poor- and non-host cultivars. They did not emphasize a need for a more diverse selection of resistant cultivars. From the grower's perspective, the main opportunity of resistant crop rotation is the integration of suppressive winter cover crops. The main challenge is the small market size for most non-host crops. Additional interactive meetings are needed to stimulate the creation of new ideas and to refine the vision and direction of research in a cooperative manner. Close

• 85. [Article] Estimates of genetic variance and heterosis in F₁ winter x spring barley crosses (Hordeum vulgare, L.)

  Four winter and four spring barley cultivars along with their F₁ hybrids were grown on the Hyslop Agronomy Farm near Corvallis, Oregon, a high rainfall site (over 1000 mm annually) located in the Willamette Valley. ...

  Citation × Citation Citation Abstract Copy Title: Estimates of genetic variance and heterosis in F₁ winter x spring barley crosses (Hordeum vulgare, L.) Author: Harrabi, Moncef Mohamed Four winter and four spring barley cultivars along with their F₁ hybrids were grown on the Hyslop Agronomy Farm near Corvallis, Oregon, a high rainfall site (over 1000 mm annually) located in the Willamette Valley. The experiment consisted of four replications. Ten seeds of each F₁ and parents were seeded in a three meter row. Plants were spaced 30 cm between and within the rows. Investigations were made to evaluate the presence of hybrid vigor when hybridizing winter and spring barley. Gene action estimates contributing to yield and its components were obtained. Additional information concerning the inheritance and the association of 12 agronomic traits and yield were also evaluated. The data were analyzed by using the factorial technique, analysis of variance, correlations, path-coefficient, parent-progeny regressions, and by polynomial and multiple regressions. The traits measured were: (1) total yield per plant, (2) kernel weight, (3) tiller number per plant, (4) kernel number per spike, (5) heading date, (6) plant height, (7) flag leaf area, (8) flag leaf width, (9) flag leaf length, (10) culm diameter, (11) head length, and (12) head extrusion. Heterobeltiosis was observed in all of the hybrids except in the cross between Adair and Short Wocus. The absence of hybrid vigor in this cross may be attributed to the fact that these two parents are closely related. Combining ability analysis as well as narrow sense heritability estimates indicated that additive gene action is more predominant in the expression of heading date, plant height, tiller number, head length, culm diameter, flag leaf width and kernel weight. Heterobeltiosis and high SCA estimates were observed in most of the hybrids for yield per plant and kernel number per spike. This implies that most of the genetic variation associated with these two traits resulted from non-additive gene action. The high SCA estimate observed for head extrusion indicates that this trait appeared to be controlled by non-additive gene action. Both additive and nonadditive gene action are important for the expression of flag leaf area and flag leaf length. When the 12 traits were correlated and the r values partitioned into direct and indirect effects it was observed that tiller number, kernel weight and kernel number per spike exerted the highest direct effect on yield. Plant height had a small positive direct effect, but an indirect effect on yield through kernel weight. It was further observed that a negative association exists between tiller number and kernel weight. This indicates that, in this barley population, it would be difficult to select for a plant containing large grain type and short stature, but it may be easy to select short plants with a relatively large number of tillers and high kernel number per spike. Path coefficient analysis indicated further that flag leaf area has a negative direct effect on yield and the remaining six traits have a negligible or no direct effect on yield, indicating that these traits can not be used as selection criteria. More genetic variability for tiller number and kernel number per spike was noted in the winter barley while more genetic variability for kernel weight was found in the spring barley. The results of this study suggest that increases in yield could be achieved by selecting plants with relatively high tiller number and high kernel weight. Selection for a high kernel number per spike can be accomplished by selecting for large culms and longer peduncle. By this procedure the breeder can take advantage of the additive genetic variance associated with tiller number and kernel weight and by the positive correlation that exists between culm size and peduncle length with kernel number per spike. Title: Estimates of genetic variance and heterosis in F₁ winter x spring barley crosses (Hordeum vulgare, L.) Author: Harrabi, Moncef Mohamed Four winter and four spring barley cultivars along with their F₁ hybrids were grown on the Hyslop Agronomy Farm near Corvallis, Oregon, a high rainfall site (over 1000 mm annually) located in the Willamette Valley. The experiment consisted of four replications. Ten seeds of each F₁ and parents were seeded in a three meter row. Plants were spaced 30 cm between and within the rows. Investigations were made to evaluate the presence of hybrid vigor when hybridizing winter and spring barley. Gene action estimates contributing to yield and its components were obtained. Additional information concerning the inheritance and the association of 12 agronomic traits and yield were also evaluated. The data were analyzed by using the factorial technique, analysis of variance, correlations, path-coefficient, parent-progeny regressions, and by polynomial and multiple regressions. The traits measured were: (1) total yield per plant, (2) kernel weight, (3) tiller number per plant, (4) kernel number per spike, (5) heading date, (6) plant height, (7) flag leaf area, (8) flag leaf width, (9) flag leaf length, (10) culm diameter, (11) head length, and (12) head extrusion. Heterobeltiosis was observed in all of the hybrids except in the cross between Adair and Short Wocus. The absence of hybrid vigor in this cross may be attributed to the fact that these two parents are closely related. Combining ability analysis as well as narrow sense heritability estimates indicated that additive gene action is more predominant in the expression of heading date, plant height, tiller number, head length, culm diameter, flag leaf width and kernel weight. Heterobeltiosis and high SCA estimates were observed in most of the hybrids for yield per plant and kernel number per spike. This implies that most of the genetic variation associated with these two traits resulted from non-additive gene action. The high SCA estimate observed for head extrusion indicates that this trait appeared to be controlled by non-additive gene action. Both additive and nonadditive gene action are important for the expression of flag leaf area and flag leaf length. When the 12 traits were correlated and the r values partitioned into direct and indirect effects it was observed that tiller number, kernel weight and kernel number per spike exerted the highest direct effect on yield. Plant height had a small positive direct effect, but an indirect effect on yield through kernel weight. It was further observed that a negative association exists between tiller number and kernel weight. This indicates that, in this barley population, it would be difficult to select for a plant containing large grain type and short stature, but it may be easy to select short plants with a relatively large number of tillers and high kernel number per spike. Path coefficient analysis indicated further that flag leaf area has a negative direct effect on yield and the remaining six traits have a negligible or no direct effect on yield, indicating that these traits can not be used as selection criteria. More genetic variability for tiller number and kernel number per spike was noted in the winter barley while more genetic variability for kernel weight was found in the spring barley. The results of this study suggest that increases in yield could be achieved by selecting plants with relatively high tiller number and high kernel weight. Selection for a high kernel number per spike can be accomplished by selecting for large culms and longer peduncle. By this procedure the breeder can take advantage of the additive genetic variance associated with tiller number and kernel weight and by the positive correlation that exists between culm size and peduncle length with kernel number per spike. Close

• 86. [Article] How to reduce bee poisoning from pesticides

  Published December 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http:/...

  Citation × Citation Citation Abstract Copy Title: How to reduce bee poisoning from pesticides Author: Washington State University. Extension, Barbour, Jim, Pacific Northwest Cooperative Extension, Johansen, Erik, Brewer, Linda J., University of Idaho. Extension, Riedl, Helmut., Oregon State University. Extension Service Published December 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: How to reduce bee poisoning from pesticides Author: Washington State University. Extension, Barbour, Jim, Pacific Northwest Cooperative Extension, Johansen, Erik, Brewer, Linda J., University of Idaho. Extension, Riedl, Helmut., Oregon State University. Extension Service Published December 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 87. [Article] Phenology and monitoring of the cabbage maggot, Delia radicum (L.), in brassica root crops

  In Oregon’s northern Willamette Valley, cabbage maggot (CM), Delia radicum (L.) (Diptera: Anthomyiidae) often renders Brassica root crops unmarketable. Scheduled insecticides are the only current control. ...

  Citation × Citation Citation Abstract Copy Title: Phenology and monitoring of the cabbage maggot, Delia radicum (L.), in brassica root crops Author: Dreves, Amy J. In Oregon’s northern Willamette Valley, cabbage maggot (CM), Delia radicum (L.) (Diptera: Anthomyiidae) often renders Brassica root crops unmarketable. Scheduled insecticides are the only current control. Studies were conducted to: 1) describe and characterize spring emergence of CM flies and their seasonal flight activity relative to degree-day (DD) accumulations; 2) measure impact of CM by assessing crop damage; 3) define influence of seasonal planting and harvest dates relative to root damage; 4) identify the occurrence of ovipositional activity in relation to time of season, age of crop, distribution in field; and 5) study relationships among flight activity, oviposition, and crop damage. Commercial rutabaga and turnip fields were studied from 2001 through 2005. Spring emergence from overwintering puparia was monitored using emergence cages. A bimodal spring emergence pattern for CM was observed: approximately 70% of the overwintering population peaked in late March. A second smaller peak was observed at the end of May. The mean DD accumulations at 10, 50, and 95% of spring emergence using a lower and upper developmental threshold of 4.3°C and 30°C beginning January 1 had corresponding DD values of 200 ± 50.2 (8 March), 330 ± 22.2 (4 April) and 762 ± 60.1 (28 May), respectively. Spring flight patterns, monitored with yellow water traps, mirrored the bimodal emergence pattern but with an apparent lag. Rutabaga crops sustained 1.7x higher damage levels than did turnip crops. Damage caused by CM was significantly greater (37-52%) in spring crops planted prior to an accumulated 900 DD, than in summer crops planted after 900 degree-days or in fields planted in the fall after 1500 DD. Maggot damage is abated by planting after the spring flight (> 900 DD) and harvesting before the relative peak of fall flight (< 2600 DD). Fields documented with less than an average of 100 flies collected in a water trap over a crop’s duration in the field, had the lowest sum of percent weekly egg assessments (38.6 ± 6.1; based on 7 weekly egg level assessments), and the least amount of root infestation by CM (< 20% per 60 root samples). Fields with greater than 100 flies per trap over crop duration in the field had the greatest sum frequency of plants with eggs (95.6 ± 6.7), and the most CM root infestation (> 20%). Oviposition significantly increased in fields at 30.9 (± 1.1) days after seeding. Large plants with > 5 leaves, root diameter of > 6 mm, and increased crop canopy were more heavily infested with CM eggs than smaller plants. A strong relationship was seen between the frequency of older plants with eggs (> 9 leaves, >19 mm root size and partially-closed canopy) and crop damage at harvest (r2 = 0.83). Egg incidence was significantly higher (46%) on plants located on the outside periphery of fields than on plants located in the field centers. Spring monitoring of emergence and flight arrival, and density of D. radicum allows useful predictions of oviposition and crop damage. Appropriate oviposition assessment, combined with timely planting and harvesting schedules, and use of egg thresholds to time treatments could greatly reduce maggot populations. Title: Phenology and monitoring of the cabbage maggot, Delia radicum (L.), in brassica root crops Author: Dreves, Amy J. In Oregon’s northern Willamette Valley, cabbage maggot (CM), Delia radicum (L.) (Diptera: Anthomyiidae) often renders Brassica root crops unmarketable. Scheduled insecticides are the only current control. Studies were conducted to: 1) describe and characterize spring emergence of CM flies and their seasonal flight activity relative to degree-day (DD) accumulations; 2) measure impact of CM by assessing crop damage; 3) define influence of seasonal planting and harvest dates relative to root damage; 4) identify the occurrence of ovipositional activity in relation to time of season, age of crop, distribution in field; and 5) study relationships among flight activity, oviposition, and crop damage. Commercial rutabaga and turnip fields were studied from 2001 through 2005. Spring emergence from overwintering puparia was monitored using emergence cages. A bimodal spring emergence pattern for CM was observed: approximately 70% of the overwintering population peaked in late March. A second smaller peak was observed at the end of May. The mean DD accumulations at 10, 50, and 95% of spring emergence using a lower and upper developmental threshold of 4.3°C and 30°C beginning January 1 had corresponding DD values of 200 ± 50.2 (8 March), 330 ± 22.2 (4 April) and 762 ± 60.1 (28 May), respectively. Spring flight patterns, monitored with yellow water traps, mirrored the bimodal emergence pattern but with an apparent lag. Rutabaga crops sustained 1.7x higher damage levels than did turnip crops. Damage caused by CM was significantly greater (37-52%) in spring crops planted prior to an accumulated 900 DD, than in summer crops planted after 900 degree-days or in fields planted in the fall after 1500 DD. Maggot damage is abated by planting after the spring flight (> 900 DD) and harvesting before the relative peak of fall flight (< 2600 DD). Fields documented with less than an average of 100 flies collected in a water trap over a crop’s duration in the field, had the lowest sum of percent weekly egg assessments (38.6 ± 6.1; based on 7 weekly egg level assessments), and the least amount of root infestation by CM (< 20% per 60 root samples). Fields with greater than 100 flies per trap over crop duration in the field had the greatest sum frequency of plants with eggs (95.6 ± 6.7), and the most CM root infestation (> 20%). Oviposition significantly increased in fields at 30.9 (± 1.1) days after seeding. Large plants with > 5 leaves, root diameter of > 6 mm, and increased crop canopy were more heavily infested with CM eggs than smaller plants. A strong relationship was seen between the frequency of older plants with eggs (> 9 leaves, >19 mm root size and partially-closed canopy) and crop damage at harvest (r2 = 0.83). Egg incidence was significantly higher (46%) on plants located on the outside periphery of fields than on plants located in the field centers. Spring monitoring of emergence and flight arrival, and density of D. radicum allows useful predictions of oviposition and crop damage. Appropriate oviposition assessment, combined with timely planting and harvesting schedules, and use of egg thresholds to time treatments could greatly reduce maggot populations. Close

• 88. [Article] Detection and Quantification of Pratylenchus thornei in DNA Extracted from Soil Using Real-Time PCR

  This is the publisher’s final pdf. The published article is copyrighted by American Phytopathological Society and can be found at: www.apsnet.org/.

  Citation × Citation Citation Abstract Copy Title: Detection and Quantification of Pratylenchus thornei in DNA Extracted from Soil Using Real-Time PCR Author: Smiley, Richard W., Okubara, Patricia A., Yan, Guiping This is the publisher’s final pdf. The published article is copyrighted by American Phytopathological Society and can be found at: www.apsnet.org/. Title: Detection and Quantification of Pratylenchus thornei in DNA Extracted from Soil Using Real-Time PCR Author: Smiley, Richard W., Okubara, Patricia A., Yan, Guiping This is the publisher’s final pdf. The published article is copyrighted by American Phytopathological Society and can be found at: www.apsnet.org/. Close

• 89. [Article] Possible association between grain protein content and yield as influenced by harvest index and biological yield in selected hard red winter wheat (Triticum aestivum L.) crosses

  Grain yield and grain protein are often negatively associated in wheat. When yield increases and grain protein decreases, there can be an adverse effect on the milling and baking quality if the desired ...

  Citation × Citation Citation Abstract Copy Title: Possible association between grain protein content and yield as influenced by harvest index and biological yield in selected hard red winter wheat (Triticum aestivum L.) crosses Author: Costa, José María Grain yield and grain protein are often negatively associated in wheat. When yield increases and grain protein decreases, there can be an adverse effect on the milling and baking quality if the desired end product is bread flour. It has been suggested that this inverse association is the result of selecting for a higher harvest index (ratio of grain yield to total biomass), to enhance grain yield. Parents, Fl, F2, and F3 generations of three crosses and reciprocal backcrosses of one cross were space-planted to study the association of grain protein content with grain and biological yields, harvest index, and related traits. Selection P5221, a high protein selection, was a common parent in crosses with three different genotypes. Differences were observed among generations within crosses for biological yield, grain yield, harvest index, grain protein content, grain hardness, and protein yield. The coefficients of variation for the measured traits were low for the three crosses. No associations between grain protein content and grain yield were observed in the populations studied. The largest association detected was between harvest index and grain protein. The r values ranged from -0.39 to -0.46, and rho was not different from -0.50 in two of the crosses. Path coefficient analyses revealed that this association was mostly due to the direct effect of harvest index on grain protein content, with little direct or indirect effect via other plant traits. In the cross P5221/ORCR 8313, biological yield exhibited a moderately large (0.64) direct effect on grain protein content; however this was offset by the negative indirect effect of tiller number. The R2 of the path analyses were relatively small for the three crosses, indicating that most of the variation in grain protein content was not explained by the variables included in the analyses. A possible negative association between grain protein content and harvest index, although moderate, suggests that selection for high yield should not be based on further increases of harvest index because grain protein could decrease. Title: Possible association between grain protein content and yield as influenced by harvest index and biological yield in selected hard red winter wheat (Triticum aestivum L.) crosses Author: Costa, José María Grain yield and grain protein are often negatively associated in wheat. When yield increases and grain protein decreases, there can be an adverse effect on the milling and baking quality if the desired end product is bread flour. It has been suggested that this inverse association is the result of selecting for a higher harvest index (ratio of grain yield to total biomass), to enhance grain yield. Parents, Fl, F2, and F3 generations of three crosses and reciprocal backcrosses of one cross were space-planted to study the association of grain protein content with grain and biological yields, harvest index, and related traits. Selection P5221, a high protein selection, was a common parent in crosses with three different genotypes. Differences were observed among generations within crosses for biological yield, grain yield, harvest index, grain protein content, grain hardness, and protein yield. The coefficients of variation for the measured traits were low for the three crosses. No associations between grain protein content and grain yield were observed in the populations studied. The largest association detected was between harvest index and grain protein. The r values ranged from -0.39 to -0.46, and rho was not different from -0.50 in two of the crosses. Path coefficient analyses revealed that this association was mostly due to the direct effect of harvest index on grain protein content, with little direct or indirect effect via other plant traits. In the cross P5221/ORCR 8313, biological yield exhibited a moderately large (0.64) direct effect on grain protein content; however this was offset by the negative indirect effect of tiller number. The R2 of the path analyses were relatively small for the three crosses, indicating that most of the variation in grain protein content was not explained by the variables included in the analyses. A possible negative association between grain protein content and harvest index, although moderate, suggests that selection for high yield should not be based on further increases of harvest index because grain protein could decrease. Close

• 90. [Article] Cultural management of corn root rot: Report to the Oregon Processed Vegetable Commission, 2005

  1. Rotbusters Field Survey.  Kokanee and Basin were the only varieties sampled in 2005. There was a significant relationship between radicle rot severity and gross yield for Kokanee but not for Basin.  ...

  Citation × Citation Citation Abstract Copy Title: Cultural management of corn root rot: Report to the Oregon Processed Vegetable Commission, 2005 Author: Stone, Alex, Hertel, Michael, Miyazoe, Mikio, Weston, Galen 1. Rotbusters Field Survey.  Kokanee and Basin were the only varieties sampled in 2005. There was a significant relationship between radicle rot severity and gross yield for Kokanee but not for Basin.  In previous years, we have shown that for Jubilee, approximately 3 tons of gross yield are lost in fields of very high root rot potential compared to those of very low root rot potential. We have also shown that Coho and SSJ+ lose about half that, or about 1.5 tons. In 2005, across all fields scouted, approximately 1.5 tons of gross yield in Kokanee were lost when this variety was planted into fields of very high root rot potential relative to planting into fields of very low root rot potential.  Kokanee, Coho and Basin are higher yielding than either Jubilee or SSJ+, regardless of the root rot potential of the soil. 2. Impacts of High Biomass Cover Cropping on Root Rot and Yield of Sweet Corn.  In a research station replicated field trial, no late summer or winter cover crop treatments significantly suppressed root rot or increased yield of sweet corn.  In a pseudo-replicated on-farm trial, all winter cover crop treatments (oats “Saia”, arugula “Nemfix” and mustard mix “Caliente” strongly suppressed nodal root rot of sweet corn but had no significant effect on sweet corn yield.  It is likely that the effects of cover crops on root rot and yield of sweet corn are the combined result of the effects of cover crop management on microbial activity (general suppression), nitrogen mineralization, plant available water, and possibly other soil factors. More work is required to better understand how to best manage high biomass cover crops to improve sweet corn productivity. Title: Cultural management of corn root rot: Report to the Oregon Processed Vegetable Commission, 2005 Author: Stone, Alex, Hertel, Michael, Miyazoe, Mikio, Weston, Galen 1. Rotbusters Field Survey.  Kokanee and Basin were the only varieties sampled in 2005. There was a significant relationship between radicle rot severity and gross yield for Kokanee but not for Basin.  In previous years, we have shown that for Jubilee, approximately 3 tons of gross yield are lost in fields of very high root rot potential compared to those of very low root rot potential. We have also shown that Coho and SSJ+ lose about half that, or about 1.5 tons. In 2005, across all fields scouted, approximately 1.5 tons of gross yield in Kokanee were lost when this variety was planted into fields of very high root rot potential relative to planting into fields of very low root rot potential.  Kokanee, Coho and Basin are higher yielding than either Jubilee or SSJ+, regardless of the root rot potential of the soil. 2. Impacts of High Biomass Cover Cropping on Root Rot and Yield of Sweet Corn.  In a research station replicated field trial, no late summer or winter cover crop treatments significantly suppressed root rot or increased yield of sweet corn.  In a pseudo-replicated on-farm trial, all winter cover crop treatments (oats “Saia”, arugula “Nemfix” and mustard mix “Caliente” strongly suppressed nodal root rot of sweet corn but had no significant effect on sweet corn yield.  It is likely that the effects of cover crops on root rot and yield of sweet corn are the combined result of the effects of cover crop management on microbial activity (general suppression), nitrogen mineralization, plant available water, and possibly other soil factors. More work is required to better understand how to best manage high biomass cover crops to improve sweet corn productivity. Close