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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Response to fenamiphos, extraction techniques and population dynamics of Pratylenchus penetrans on western Oregon red raspberry

Lolas, Mauricio 15 March 1991 (has links)
The effects of fenamiphos on soil and root populations of Pratylenchus penetrans were evaluated in four red raspberry cv. Willamette fields in Northwestern Oregon. Field 1 was a silty clay loam with 53% organic matter (OM). Field 2 and 3 were silty loam soils with 3.25 and 2.55% OM, respectively and field 4 was a silty clay with 7.1% OM. The nematicide, fenamiphos (10 kg a.i./ha) was applied in broadcast or band treatments on November 15, 1989. Additional plots in field 3, received a band-nematicide treatment on December 28, 1989 to evaluate the effect of application date on the control of P. penetrans in red raspberry. Field 4 had plots in sites with and without grass and weed ground cover in the aisles between raspberry rows to examine effects of ground cover on nematicide efficacy. Nematodes from soil and roots were sampled monthly from all plots in each field from October 1989 to October 1990. Soil populations of P. penetrans sampled within rows decreased between the October and December sampling dates in all four fields. Soil populations in 3 fields increased in density during mid-summer and reached their highest peak in the middle of September. A similar pattern occurred in P. penetrans soil populations from plots with or without ground cover in aisles between rows of raspberry in field 4. However, in this field, numbers increased in July and reached their peak density in August. Root populations of P. penetrans from red raspberry reached their highest number during spring and summer at all fields. No significant (P>0.05) differences in effectiveness of fenamiphos were detected between band and broadcast method of application and, also between the 2 application dates. Seasonal mean densities of soil populations from band application was only significantly lower than in nontreated controls in areas with ground cover in field 4, respectively. High variability in the numbers of P. penetrans in soil and roots of raspberry was observed throughout the year. Therefore, conclusions about the effectiveness of fenamiphos were difficult to assess. The efficiency of Baermann funnels was 43.9%, when a known number of P. penetrans was added to soil. Total yields of P. penetrans extracted from raspberry roots by mist chamber root extraction (MCRE) were higher (P = 0.05) than yields extracted by polyethylene plastic bag root incubation (PBRI). Approximately 90% of the total P. penetrans recovered was achieved after three and seven days of extraction for PBRI and MCRE, respectively. However, the extraction efficiency of MCRE was 30% higher than PBRI and the daily recovery lasted 28 and 18 days, respectively. / Graduation date: 1992
32

Edible coatings to improve storability and enhance nutritional value of strawberries (Fragaria ananassa) and raspberries (Rubus ideaus)

Han, Chunran 15 March 2004 (has links)
Graduation date: 2004
33

Characterization, epidemiology, and ecology of a virus associated with black raspberry decline

Halgren, Anne B. 24 January 2006 (has links)
The objective of this study was to characterize an unknown agent associated with decline in black raspberry (Rubus occidentalis) in Oregon. A virus was found consistently associated with decline symptoms of black raspberries and was named Black raspberry decline associated virus (BRDaV). Double stranded RNA extraction from BRDaV-infected black raspberry revealed the presence of two bands of approximately 8.5 and 7 kilobase pairs, which were cloned and sequenced. The complete nucleotide sequences of RNA 1 and RNA 2 are 7581 nt and 6364 nt, respectively, excluding the 3' poly(A) tails. The genome structure was identical to that of Strawberry mottle virus (SMoV), with the putative polyproteins being less than 50% identical to that of SMoV and other related sequenced viruses. The final 189 amino acids of the RNA-dependent- RNA-polymerase (RdRp) reveal an unusual indel with homology to AlkB-like protein domains, suggesting a role in repair of alkylation damage. This is the first report of a virus outside the Flexiviridae and ampeloviruses of the Closteroviridae to contain these domains. An RT-PCR test was designed for the detection of BRDaV from Rubus tissue. BRDaV is vectored non-persistently by the large raspberry aphid Amphorophora agathonica, the green peach aphid Myzus persicae, and likely nonspecifically by other aphid species. Phylogenetic analysis of conserved motifs of the RdRp, helicase, and protease regions indicate that BRDaV belongs to the Sadwavirus genus. To assess the rate of spread BRDaV, four newly planted fields of black raspberries (Rubus occidentalis) in Oregon were studied for three years. In an effort to characterize the suspected complexity of synergistic interactions between BRDaV and other Rubus-infecting viruses, the prevalence of ten additional Rubus viruses was also monitored in the study fields. The timing of BRDaV infection as it relates to aphid populations and flights was also determined. Testing of nearby vegetation identified several symptomless Rubus hosts of BRDaV, as well as detection in multiple cultivars of black raspberry and several non-Rubus weeds. It was determined that BRDaV spreads rapidly with a low aphid threshold and consistently is associated with decline of black raspberries in Oregon. / Graduation date: 2006
34

Anthocyanin composition of red raspberry juice : influences of variety, processing, and environmental factors

Boyles, Matthew J. 10 December 1991 (has links)
Graduation date: 1992
35

Color changes in berries during processing and storage

Gizis, Evangelos John 16 May 1962 (has links)
Graduation date: 1962
36

The evaluation of raspberry pomace as a feedstuff for growing pigs

McDougall, N. Ruth January 1990 (has links)
Raspberry pomace, consisting of seeds, pulp and added rice hulls, is the residue from the pressing of raspberries for juice and concentrate production. Through the determination of chemical composition by laboratory analyses and the measurement of feeding value in animal trials, the pomace was evaluated as a feedstuff for growing pigs. Pomace contains 11.1% crude fat, 10.0% crude protein, 59.5% total dietary fibre, 7.4% soluble carbohydrates, and a gross energy level of 5220 kcal*kg⁻¹. The acid detergent residue of the pomace contains 11.7% lignin, 6.0% cutin, 2.2% acid detergent ash and 26.0% cellulose (by difference). The digestibility of dry matter, fat, protein and energy was determined. Pomace dried at 60 C, whole and ground (1mm) was fed to growing male pigs (30-35 kg) in a replicated 4X4 Latin Square design with treatments basal (B) , B plus 40% unground pomace, B plus 40% ground pomace and B plus 40% barley. Grinding of pomace significantly improved the digestibility of all parameters measured, however, the barley-soybean meal basal ration was consistently better digested than either of the pomace treatments. The digestibility of whole and ground pomace was respectively: dry matter 10.7% and 20.8% (S.E.M. 1.30), fat 24.1% and 79.7% (S.E.M. 3.47), protein 10.6% and 14.7% (S.E.M. 4.83) and energy 7.9% and 28.4% (S.E.M. 1.80). Protein quality of ground (1mm) and freeze-dried pomace was evaluated with rats in metabolism cages to produce the following values: true protein digestibility 36.0% (S.E.M. 0.66), biological value 91.0% (S.E.M. 3.46), and net protein utilization 32.7% (S.E.M. 1.15). In rat growth trials, where pomace replaced barley incrementally, growth rate was not affected at replacement levels up to 40%, although feed efficiency declined consistently as the level of pomace in the diet increased. It is suggested that raspberry pomace could replace up to 20% of an energy feedstuff in a ration for growing swine without significantly reducing growth rate or feed efficiency. / Land and Food Systems, Faculty of / Graduate
37

The total delivered cost of sieved red raspberries: a procurement optimization model

Trumble, Misty January 1900 (has links)
Master of Agribusiness / Agricultural Economics / Vincent R. Amanor-Boadu / The United States was the world’s third largest producer of raspberries (by pounds) in 2013, behind Russia and Poland. Raspberries are the third most popular berry in the United States behind strawberries and blueberries. Most U.S. production of red raspberries occurs in the states of Washington and Oregon during July and August depending on variety. Harvest and production for industrial pack typically runs for five weeks. Sieved red raspberries or single strength red raspberry puree is one of many industrial packs produced in the Pacific Northwest of the United States. Sieved red raspberries are produced by forcing fresh, cleaned and sorted red raspberries and red raspberry crumbles and pieces through a mesh screen, collected in drums or pails and stored for use in further processed products such as pies, confectioneries and other consumer food products. For this thesis, sieved berries are packed in 55-gallon steel drums lined with food grade plastic bags. They are shipped from the processing plant to a third party warehouse to be frozen and stored. The final processing plant draws on these stored frozen products for use in the production of the Company’s consumer food products. The purpose of this thesis is to review the Company’s current procurement practices of sieved red raspberries and determine how these practices may be improved to reduce its total delivered cost. We use an optimization modelling approach to assess the procurement process used by the Company. The results indicate that it is possible to reduce procurement costs and improve efficiencies by making changes to the current procurement strategy. By implementing the procurement strategy developed in this study, we show that the Company can save as much as $1.69 million per year, which is equivalent to about 20.3% of the current spend. This would suggest that adopting the optimization strategy could allow the Company to increase its total sieved raspberry utilization by as much as 0.9 million pounds per annum, all other things remaining unchanged.
38

Economic feasibility of alternative crops in Northeast Iowa to sustain family incomes

Quandahl, Kendal January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Vincent R. Amanor-Boadu / The purpose of this thesis is to identify which alternative crops could be enhance the income of Quandahl Farms the most by moving the smallest acreage from the farm’s traditional corn and soybean enterprises into its production. The considered crops are grapes, raspberries, and black currants. The objectives of this study included assessing the technical feasibility of producing the selected crops in Northeast Iowa given the agronomic conditions in the region and the agronomic requirements of the crops. The other was the assessment of the economic feasibility of the selected crops and determining the minimum acres required for each to enhance the farm’s financial situation and still allow for corn and soybeans to be the main crops. The analyses were conducted using secondary data on the selected crops from published budgets and government and extension reports as well as the historical financials of Quandahl Farms. The analyses were conducted over a 10-year horizon to ensure a significant duration of cash flow and allow the establishment of the alternative crops. In that 10-year period, the net present value of Quandahl Farms income is $214 per acre per year. Additionally, the analyses were evaluated under four alternative scenarios of prices and yield for each of the crops in addition to the base scenario. The results shows that grapes and black currants were not economically feasible in Northeast Iowa even though they were agronomically feasible. On the contrary, raspberries were found to be both technically and economically feasible in Northeast Iowa. The net present value under that base scenario for raspberries was $23,267 at a discount rate of 4.5%. Based on the net present value of corn and soybean revenue of the same period, it is estimated that taking 22 acres from the current production and putting it into raspberries would increase average farm income by $60,000. The study shows there is an opportunity to allocate a relatively small proportion of current corn and soybean acreage to raspberries to significantly increase farm incomes. As a result, it is recommended to the principals of Quandahl Farms to consider making this small investment in raspberries to protect the farm from the frequent vicissitudes of farm incomes. The next step after their agreement is to develop the business plan to implement such an investment.
39

Isolation of putative pAgK84 transconjugants from commerical cherry and raspberry plants treated with Agrobacterium radiobacter strain K84

Lu, Shu-Fen 25 August 1994 (has links)
Graduation date: 1995
40

Late yellow rust (Pucciniastrum americanum (Farl.) Arth.) of Red raspberry (Rubus idaeus L.)

Luffman, Margie January 1988 (has links)
No description available.

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