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1
Fournier, François. "Seuil économique et programme d'échantillonnage séquentiel pour le thrips de l'oignon (Thrips tabaci Lindeman) sur l'oignon." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69571.
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Very high infestation levels of Thrips tabaci Lindeman were observed on onions at Ste-Clotilde (Quebec) with seasonal means of 149 and 161 thrips/plant for 1988 and 1989 respectively. No significant differences in thrips densities were detected among six yellow onion cultivars (Capable, Flame, Norstar, Progress, Rocket, Taurus) through weekly comparisons in 1988 and biweekly comparisons in 1989.A new variable, the cumulative number of thrips-days/plant, was used to model the impact of T. tabaci on onion yields. This variable allowed for better-fitted models, especially in 1989 where greater variability of the onion yields was observed. A modified Gompertz equation gave the best fit for 1988. No yield reduction due to T. tabaci was observed up to the 1000 cumulative thrips-days/plant point, beyond which the thrips impact first increased with the feeding pressure and then gradually decreased to a minimal level corresponding to a yield loss of 43%. In 1989, thrips impact was immediate and best described by an exponential model with a maximal yield loss of 34,5%.
Economic thresholds of 964 and 251 cumulative thrips-days/plant were calculated for 1988 and 1989 respectively. Converted to thrips/leaf these correspond to 2,2 and 0,9 thrips/leaf. This conversion could facilitate their use in a field situation.
Spatial distribution of T. tabaci was analyzed in ten commercial onion fields. Within field, density was homogeneous in the majority of cases. In some fields, higher thrips densities were temporary (two consecutive weeks at most) in one or two field margins.
The Iwao method was used to calculate the acceptance boundaries of sequential sampling plans for the economic thresholds of 0,9 and 2,2 thrips/leaf and onion growth stages of 6, 7, 8, 9 and 10 green leaves. (Abstract shortened by UMI.)
2
Peters, Curtis Lee 1958. "SURFACE RESPONSE OF ONIONS TO CULTURAL TREATMENTS." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276358.
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Langenhoven, Petrus. "Invloed van bemesting op die opbrengs en kwaliteit van uie (Allium cepa L.)." Thesis, Link to the online version, 1999. http://hdl.handle.net/10019.1/1808.
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Rethwisch, Michael D. "Thrips Control on Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/214481.
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Tschorsch, Florian. "Onions in the queue." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17554.
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Performanz ist ein zentraler Bestandteil des Designs von Anonymisierungsdiensten. Ihre zunehmende Popularität führt jedoch zu einer hohen Netzwerklast, die unzulängliche Entwurfsentscheidungen imminent macht. Die Anforderungen und die vielschichtige Architektur von Anonymisierungsdiensten machen die Thematik zu einem anspruchsvollen und zugleich inspirierenden Forschungsgegenstand. Die vorliegende Arbeit diskutiert das Design von sogenannten Niedriglatenz-Anonymisierungsdiensten im Allgemeinen und dem Tor-Netzwerk als relevantesten Vertreter im Speziellen. Es werden Lösungen für eine Reihe von Forschungsfragen entwickelt, die allesamt das Ziel verfolgen, diese Overlay-Netzwerke zu verbessern und sicherer zu gestalten. Es entsteht ein fundamentales Verständnis zu Netzwerkaspekten in Anonymisierungs-Overlays, das die Netzwerklast, als vorherrschende Ursache für die schwache Performanz, thematisiert.Performance is a pivot point in the design of anonymity overlays. Due to their growing popularity, they are faced with increasing load, which makes design problems imminent. The special requirements and complex architecture of anonymity overlays renders the topic a challenging but likewise inspiring object of research. In this work, we discuss the design of low-latency anonymous communication systems in general and the Tor network as the de-facto standard in particular. We develop solutions to a number of research questions, all collectively following the aim of enhancing and securing such networks. By doing this we create a fundamental technical understanding of networking aspects in anonymity overlays and tackle the most prevalent performance issue experienced today: network congestion.
6
Umeda, Kai. "Postemergence Herbicide Weed Control in Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/214728.
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Onions treated at the 2-leaf stage of growth with the 3rd leaf just beginning to emerge with postemergence herbicides bromoxynil (Buctril®) and oxyfluorfen (Goal®) exhibited slight injury at 11 days after treatment (DAT) but had recovered to show no injury at 1 month after treatment (MAT). Annual yellow sweetclover (Melilotus officinalis) was the predominat weed in the test site and early ratings showed that Goal at 0.25 lb a.i. /A and Goal plus Buctril gave marginally acceptable control at 80 %. Buctril alone did not control clover. At 1 MAT, the clovers had recovered from the initial injury and the level of control had declined to become unacceptable.
7
Martin, Edward, Donald Slack, and E. James Pegelow. "Water Use in Vegetables - Dry Bulb Onions." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2009. http://hdl.handle.net/10150/146973.
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Umeda, K., and D. MacNeil. "Early Postemergence Herbicide Weed Control in Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/219956.
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Onions treated with bromoxynil (Buctril7) or oxyfluorfen (Goal7) at the time when the first true leaf was emerging were not injured. No significant onion crop stand reduction occurred from any of the postemergence (POST) treatments. Onion height was not affected by any of the POST treatments through the season. A single application of Goal or Buctril offered up to 7 WAT of very good weed control with excellent crop safety. Onions treated at the typical 2-leaf stage of growth with Buctril or Goal exhibited no significant crop injury. Delayed and reduced control of knotweed (Polygonum aviculare) could have contributed to the decreased onion yield in the herbicide treated onions compared to the handweeded check. Onions in the untreated check were significantly reduced compared to Goal treated onions or the handweeded check.
9
Umeda, K., and C. Fredman. "Early Postemergence Herbicide Weed Control in Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/221477.
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Oxyfluorfen (Goal®) herbicide at 0.125 to 0.25 lb. a.i./A applied postemergence (POST) to onions at the 3-leaf stage of growth effectively controlled London rocket, yellow sweetclover, and prostrate pigweed with marginal injury to onions. Earlier POST applications on 1- and 2-leaf onions caused injury and some stand reduction. Bromoxynil (Buctril®) herbicide at 0.25 lb. a.i./A applied early POST gave generally good weed control but did not adequately control sweetclover. Buctril® applied in clear weather did not injure 1-leaf onions but caused severe injury on 2- and 3-leaf onions when applied during cloudy weather conditions. Buctril® plus pendimethalin (Prowl®) tank-mix combination applied POST provided good control of London rocket, sweetclover, and prostrate pigweed; however, onion injury was severe due to applying Buctril® in cloudy weather. Buctril® and Goal® effectively controlled weeds present in the onions but timing of POST applications was critical with respect to onion size and weather conditions to minimize injury.
10
Martin, Edward C., Donald C. Slack, and E. J. Pegelow. "Water Use in Vegetables - Dry Bulb Onions." College of Agriculture, University of Arizona (Tucson, AZ), 2014. http://hdl.handle.net/10150/333152.
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Rethwisch, Michael D., Bill Daily, David Sanderson, and Charles McDaniel. "Control of Thrips in Seed Onions and Resultant Seed Yields." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/214522.
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Four insecticides were evaluated for their effect on onion seed production in Yuma County where two species on thrips (western flower and onion) were present in seed fields. Visual differences between treatments resultant from onion thrips damage was evident within 10 days after treatments were applied at flower opening. Lorsban, Ammo and Capture treatments provided control of onion thrips based on condition of seed heads. Only Ammo and Capture treatments increased seed yield as the Lorsban treatment was thought to repel bees which are needed for pollination. Pyrethroid treatments yielded 40% more than the untreated check. Damage from onion thrips to onion seed in Yuma County is conservatively calculated to currently be at least $1.1 million annually.
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Allison, Edwin. "Effects of seed adjuvants on germination and development of onions." Thesis, Cape Technikon, 2001. http://hdl.handle.net/20.500.11838/2000.
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Thesis (MTech (Agriculture))--Cape Technikon, 2001.Onion seeds (cultivar Caledon Globe), and soil into which the seedlings were planted, were treated with various adjuvants including fungicides, a seed disinfectant and a soil sterilant, as well as soil-applied growth stimulants to determine the effect of these on germination of seed, the growth of plants and the storage life of onions obtained. Three sets of germination trials were undertaken in petri dishes, and sets of seed was also sown in deep seed trays. A trial planting was made and the crop graded and stored. Seed was also sown in pots in soil obtained from a commercial undertaking where poor germination had been obtained. A portion of this soil was pasteurised and a portion inoculated with Fusarium spp. Growth of these seedlings was then followed by re-sowing in the same pots using seed of additional cultivars.
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Abbey, Lord. "Discrimination of Allium headspace volatiles affected by variations in genotype, growing environment and storage using an electronic nose." Thesis, Cranfield University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274054.
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Al-Moshileh, Abdul Rahman M. "Control of leaf development and bulbing in onions." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306787.
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Umeda, K., and N. Lund. "Effect of Prowl and Prefar Herbicides on Onions." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/214935.
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Significant onion height reduction was observed when Prowl (pendimethalin) and Prefar (bensulide) herbicide combinations were applied preemergence (PREE). The onions resumed growth but the height was still slightly reduced later in the growing season compared to the handweeded check and the standard herbicide treatment, Dacthal (DCPA). The onion crop stand emerged initially but later in the season, a significant crop stand reduction was observed for the higher rate of Prowl at 0.5 lb AI/A plus Prefar. A lower rate of Prowl at 0.25 lb AI/A plus Prefar also caused a reduction of the onion stand compared to the handweeded check or Dacthal.
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Sreeramoju, Mahendra K. "PREPARATION, CHARACTERIZATION AND APPLICATIONS OF FUNCTIONALIZED CARBON NANO-ONIONS." UKnowledge, 2013. http://uknowledge.uky.edu/chemistry_etds/20.
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Carbon nano-onions (CNOs) discovered by Ugarte in 1992 are multi-layered fullerenes that are spherical analogs of multi-walled carbon nanotubes with diameters varying from 6 nm to 30 nm. Among the various methods of synthesis, CNOs prepared by graphitization of nanodiamonds (N-CNOs) and underwater electric arc of graphite rods (A-CNOs) are the subject of our research. N-CNOs are considered as more reactive than A-CNOs due to their smaller size, high curvature and surface defects.
This dissertation focuses on structural analysis and surface functionalization of N- CNOs with diameters ranging from 6—10 nm. Synthetic approaches such as oleum- assisted oxidation, Freidel-Crafts acylation and Billups reductive alkylation were used to functionalize N-CNOs to improve their dispersion properties in aqueous and organic solvents. Functionalized N-CNOs were characterized using various techniques such as TGA, TG-MS, Raman spectroscopy and pH-titrimetry. We designed an experimental method to isolate polycyclic aromatic adsorbates formed on the surface of oleum oxidized N-CNOs (ON-CNOs) and characterized them.
A-CNOs, on the other hand are bigger than N-CNOs with diameters ranging from 20—40 nm. In this dissertation, we discuss the preparation of graphene structures by unzipping of A-CNOs using KMnO4 as oxidizing agent. These graphene structures were characterized using powder X-ray diffraction, TGA, BET nitrogen adsorption/desorption studies and compressed powder conductivity.
This dissertation also focuses on lithiation/delithiation studies of N-CNOs, A- CNOs and A-CNO-derived graphene structures to use them as negative electrode materials in lithium-ion batteries. The cycling performances of these materials at a charge/discharge rate of C/10 were discussed. The cycling performance of N-CNOs was tested at faster charge/discharge rate of C.
17
Chanda, Chrispin Tumeo. "Manipulation and prediction of flower initiation in tropical onions." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361999.
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Gadalla, Suleiman Omar. "Inhibition of sprouting of onions during storage and marketing." Thesis, Cranfield University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340347.
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Crévier, Hélène A. "Cultural methods for dehydrating onion production in Quebec, with particular reference to the fluid drilling technique." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65969.
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MacManus, Gerard P. V. "Development and extension of a disease forecasting and chemical control system for onion downy mildew /." St. Lucia, Qld, 2000. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16115.pdf.
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Montalti, Massimo. "Spectroscopical investigation of carbon nanostructures : carbon nanotubes and carbon onions." Thesis, University of Newcastle Upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413968.
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Dolman, G. "Density trials with systematic designs on intercropped carrots and onions." Thesis, University of Reading, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354069.
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Moore, William F. "Vic Onion." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1419072621.
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Nicholson, P. "Basal rot of narcissus." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382245.
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Hagler, James Robert. "Basic aspects of onion pollination." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184512.
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Difficulties in pollen transfer have adversely affected seed production of hybrid onion (Allium cepa L.) in the United States. Six onion cultivars were examined for differential attractiveness to the honey bee (Apis mellifera L.). Honey bees clearly discriminated between the onion cultivars in both open plots and caged plots. Nectar secretion, nectar sugar concentration, nectar sugar composition, mectar potassium content, and flower phenology were correlated with honey bee visitation. Nectar secretion rates ranged from 0.54 to 0.84 ul per floret per day. Onion cultivars also demonstrated differential flowering potential. The cultivars produced from 176 to 359 flowers per umbel with 32 to 74 umbels per 30 onions. All onion cultivars examinaed contained viscous nectar with sugar concentrations ranging from 51 to 65% of total dissolved solids. Onion nectar was analyzed by gas chromatography to determine qualitative sugar differences among onion cultivars. All cultivars were hexose dominant with an approximately 1:1 fructose:glucose ratio. However, fructose was slightly more abundant than glucose. Sucrose was much less abundant than the hexose sugars. Atomic absorption spectrophotometry revealed little difference in potassium content among the A. cepa cultivars. Nectar potassium levels ranged from 5,300 ppm to 6,900 ppm. Cultivars with higher nectar potassium levels had fewer honey bee visits. Two honey bee bioassays were conducted. The first bioassay simulated the sugar and potassium composition of each onion cultivar. The honey bees selectively foraged on simulated nectars with low potassium and high sugar concentrations. The second bioassay was designed to test honey bee response to "phenolic-rich" solutions. The natural compounds tested were dilutions of salt cedar (Tamarix pentandra Pall.) honey, almond (Prunus dulcis Mill.) honey, and aloe (Aloe littoralis L.) nectar. The pure synthetic compounds tested were caffeic acid and genestic acid. Generally, honey bees foraged preferentially on the lower phenolic concentrations, indicating that compounds high in phenolic composition inhibit honey bee foraging. Finally, seed yields of each of the cultivars were compared. Wide variations in yields were correlated with honey bee visitation, sugar composition, potassium levels, and flower phenology.
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Blank, V. D., A. N. Kirichenko, A. K. Aseev, V. N. Denisov, I. A. Perezhogin, B. A. Kulnitskiy, and A. A. Nuzhdin. "Influence of Shear Deformation on Carbon Onions Stability under High Pressure." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35018.
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The influence of shear deformation on carbon onions stability under high pressure up to 45 GPa was
investigated in a Shear Diamond Anvil Cell (SDAC) by the Raman spectroscopy and the Transmission
Electron Microscopy (TEM). At shear less then 40 degrees the carbon onions are stable up to 30 GPa. Biger shear deformation leads to increasing of size and destruction of the onions and to formation of sp3 C-C
bonds. At pressure exceeded 45 GPa shear deformation leads to diamond-like carbon (DLC) formation.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35018
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Umeda, K., and C. Fredman. "Dacthal® Herbicide Rate Comparison for Preemergence Weed Control in Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/221476.
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DCPA (Dacthal®) herbicide was applied preemergence (PE) to the soil surface after onion planting and no crop injury was observed for rates of 5.3, 7.5, and 10.5 lb. a.i. /A at one of two locations. Dacthal® gave good control of London rocket and cheeseweed (90 -94 %) at one location and marginal control at the second location (79 -85 %). Dacthal® did not exhibit a rate response to control the two weeds common to both locations. The lower rate of Dacthal® did not differ in efficacy compared to higher rates to completely control lambsquarters and nettleleaf goosefoot. All rates of Dacthal® marginally controlled yellow sweetclover and other mustard weeds present. Dacthal® provided adequate weed control to allow onion stand establishment.
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Umeda, K., and G. Gal. "Evaluation of Nortron® Herbicide for Preemergence Weed Control in Onions." College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/221634.
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An exploratory field study was conducted to evaluate the efficacy and safety of Nortron® (ethofumesate) herbicide for potential use in an onion weed control program. A rate range of 1.0 to 2.5 lb AI/A applied preemergence (PREE) demonstrated good safety on onions and no injury or crop stand reduction was observed. Sowthistle was the most numerous weed present and Nortron did not reduce it relative to the untreated check. Dacthal® (DCPA) significantly reduced the number of sowthistle relative to the untreated and to Nortron treatments. Onion height was reduced by Dacthal about 40 %.
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Dalal, Ketan. "Counting the onion." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80247.
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Iteratively computing and discarding a set of convex hulls creates a structure known as an "onion". In this thesis, we show that the expected number of layers of a convex hull onion for n uniformly and independently distributed points in a disk is theta( n23 ). Additionally, we show that in general the bound is theta( n2d+1 ) for points distributed in a d-dimensional ball. Further, we show that this bound holds more generally for any fixed, bounded, full-dimensional shape with a non-empty interior. The results of this thesis were published in Random Structures and Algorithms (2004) [1].
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Grenier, Aline M. "Influence of selected endomycorrhizal fungi and phosphorus fertilization on the growth and mineral nutrition of onion grown in newly reclaimed organic soil." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69533.
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Onions are highly responsive to endomycorrhizae and improved plant growth is among the benefits associated with this symbiosis, particularly in low phosphorus soils. Although this crop is grown extensively in organic soils, few studies have been conducted on these. Onion plants (Allium cepa L. cv. Norstar) were inoculated with Glomus aggregatum Schenck & Smith, Glomus clarum Nicolson & Schenck, Glomus fasciculatum Gerdemann & Trappe, Glomus intraradix Schenck & Smith and Glomus versiforme (Karst.) Berch and grown in the field and under controlled conditions to evaluate their efficiency in newly reclaimed organic soil of low P fertility. Three species were selected to evaluate the effects of introduced endomycorrhizal fungi effects and P fertilization (equivalent to 0, 24 and 48 kg P ha$ sp{-1}$) on the growth and mineral nutrition of onion plants.Introducing endomycorrhizal fungi in non-sterile soil did not affect the growth and mineral nutrition of onion. Crop maturity was advanced when plants were inoculated, however. Increasing levels of P fertilization did not depress root colonization and onion growth was increased significantly at the highest rate only. These results suggest that higher levels than recommended could be used in this soil. Inoculation in $ gamma$-irradiated (10 kGy, $ sp{60}$Co) soil alleviated excessive Mn absorption by onion plants. Adding P fertilizer depressed growth and root colonization when plants were inoculated with G. clarum and G. intraradix and was related to the low irradiance levels used in this study. G. versiforme appeared to be the most efficient of the introduced species.
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Schorr, Marcio Renan Weber. "Storage of crioula and bola precoce onions under refrigeration and controlled atmosphere." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/5082.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorTake into account the crescent consumers demand by quality foods and the need of constant supply of vegetables products, the aim of this study was to evaluate the conservation of Crioula and Bola Precoce onions stored in different controlled atmosphere (CA), relative humidity (RH), temperature and ethylene conditions. Were evaluated four experiments with cv. Crioula and one with cv Bola Precoce. In the Crioula experiment 1, was tested the effect of different O2 and CO2 levels in storage atmosphere, two RH and two temperatures levels. Crioula experiment 2 tested three RH levels (75, 80 and 85%), experiment 3 tested three temperature levels (0.5, -0.5 and -1.0 °C) and experiment 4 tested the effect of presence or absence of ethylene 10 μl l-1, all in cold storage (CS). Bola Precoce experiment conditions are identical to Crioula experiment 1. The analyses were realized after six months of storage. CA decreased the breaking of dormancy and the bulb sprout onset in relation to CS. Low O2 and high CO2 increased the response from CA on sprout development process. Respiratory rate of bulbs gradually decreased during shelf-life, being less in CA stored bulbs. The mainly form of mass loss was due to respiration in Crioula and due to water loss in Bola Precoce . CA, mainly with 0.5+2.0 (kPa O2+kPa CO2), reduced aliinase activity and the generation of precursor compounds of onion flavor, beyond decrease the soluble solids consume and polyphenols level. Therefore, CA decrease the bulb metabolism during storage, reflecting in retard in breaking of dormancy and sprout onset, beyond maintain better post-harvest bulb quality. Better results were obtained in AC 0.5+2.0 (kPa O2+kPa CO2).
Tendo em vista a crescente demanda do mercado consumidor por alimentos com qualidade e a necessidade de suprimento constante de produtos de origem vegetal, o objetivo deste trabalho foi avaliar a conservação de cebolas Crioula e Bola Precoce armazenadas em diferentes condições de atmosfera controlada (AC), umidade relativa (UR), temperatura e etileno. Foram realizados quatro experimentos com a cv. Crioula e um com a cv. Bola Precoce. No experimento 1, com Crioula , testou-se o efeito de diferentes níveis de O2 e CO2 na atmosfera de armazenagem, dois níveis de UR e duas temperaturas. O experimento 2 testou três níveis de UR (75, 80 e 85%), o experimento 3 testou três níveis de temperatura (0,5, -0,5 e -1,0 °C) e o experimento 4 testou a presença constante de 10 μl l-1 de etileno durante o armazenamento, todos mantidos em armazenamento refrigerado (AR). Os tratamentos testados em Bola Precoce foram iguais aos do experimento 1 de Crioula . As análises foram realizadas após seis meses de armazenamento. A AC reduziu a superação da dormência e início do processo de brotamento dos bulbos em relação ao AR. Condições com baixo nível de O2 e alto de CO2 aumentaram a resposta da AC no controle do processo de desenvolvimento dos brotos. A taxa respiratória dos bulbos reduziu gradativamente durante a vida de prateleira, sendo menor nos bulbos armazenados em AC. A principal forma de perda de massa foi através da respiração na Crioula e pela perda de água na Bola Precoce . A AC, principalmente com 0,5+2,0 (kpa O2+kpa CO2), reduziu a atividade da enzima aliinase e a geração de compostos precursores do flavor de cebolas, além de reduzir o consumo de sólidos solúveis e o teor de polifenois. Portanto, a AC reduz o metabolismo dos bulbos durante o armazenamento, refletindo em retardo na superação da dormência e início do processo de brotamento, além de manter melhor qualidade pós-colheita dos bulbos. Melhores resultados são obtidos em AC 0,5+2,0 (kPa O2+kPa CO2). .
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Parfitt, D. "Sclerotium cepivorum Berk. in onions : An investigation of alternative methods of control." Thesis, University of Hull, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377392.
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Borgohain, Rituraj. "PHYSICOCHEMICAL MODIFICATIONS AND APPLICATIONS OF CARBON NANO-ONIONS FOR ELECTROCHEMICAL ENERGY STORAGE." UKnowledge, 2013. http://uknowledge.uky.edu/chemistry_etds/24.
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Carbon nano-onions (CNOs), concentrically multilayered fullerenes, are prepared by several different methods. We are studying the properties of two specific CNOs: A-CNOs and N-CNOs. A-CNOs are synthesized by underwater arc discharge, and N-CNOs are synthesized by high-temperature graphitization of commercial nanodiamond. In this study the synthesis of A-CNOs are optimized by designing an arc discharge aparatus to control the arc plasma. Moreover other synthesis parameters such as arc power, duty cycles, temperature, graphitic and metal impurities are controlled for optimum production of A-CNOs. Also, a very efficient purification method is developed to screen out A-CNOs from carboneseous and metal impurities. In general, A-CNOs are larger than N-CNOs (ca. 30 nm vs. 7 nm diameter). The high surface area, appropriate mesoporosity, high thermal stability and high electrical conductivity of CNOs make them a promising material for various applications. These hydrophobic materials are functionalized with organic groups on their outer layers to study their surface chemistry and to decorate with metal oxide nanoparticles. Both CNOs and CNO nanocomposites are investigated for application in electrochemical capacitors (ECs). The influences of pH, concentration and additives on the performance of the composites are studied. Electrochemical measurements demonstrate high specific capacitance and high cycling stability with high energy and power density of the composite materials in aqueous electrolyte.
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Gonçalves, Natalia Martins. "Economias de escala em uma linha de onibus urbano: o enfoque micro-analitico." reponame:Repositório Institucional da UFSC, 1995. http://repositorio.ufsc.br/xmlui/handle/123456789/76226.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro TecnologicoMade available in DSpace on 2012-10-16T08:26:30Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T20:12:06Z : No. of bitstreams: 1 99385.pdf: 4712274 bytes, checksum: 5d922f0abc775aa04f7e3059e1292f03 (MD5)
O enfoque deste trabalho é o detalhamento da análise operacional de uma linha de ônibus urbano, englobando conjuntamente o ponto de vista do operador e do usuário. Neste sentido, buscou-se analisar uma situação real, com parâmetros operacionais diferenciados ao longo da linha de ônibus (tempos de parada, velocidade, distância entre pontos de parada, etc.), possibilitando um tratamento prático e mais detalhado da teoria. Por outro lado, com a diferenciação dos vários grupos de usuários em função da sua posição geográfica, avaliou-se os custos e benefícios para cada segmento de demanda de forma distributiva, considerando que o nível de serviço oferecido pelo operador não alcança da mesma forma todas as pessoas. Para ajustar a função custo generalizado dos usuários, foi realizada uma pesquisa de preferência declarada em uma linha de ônibus da cidade de Florianópolis/SC. O estudo apresenta um modelo de avaliação que possibilita a simulação de situações diversas para operador e usuários, buscando otimizar custos e benefícios.
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Bitterlich, Iris. "Weed interference and weed control in cole crops and onion." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28920.
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Additive weed competition experiments were undertaken to study the effect of lamb's-quarters (Chenopodium album) interference on direct seeded broccoli. Lamb's-quarters (3, 8, 10, 12, and 15 plants m⁻²) began to affect broccoli growth 28 to 36 days after seeding. Decreases in crop growth increased with weed density as time after seeding increased. Yield data were fitted to a rectangular hyperbolic model which indicated that even one lamb's-quarters plant m⁻² could reduce total yield by 18 to 20 percent and marketable yield (head >10 cm across) by 22 to 37 percent. Lamb's-quarters reduced total yield by reducing average head weight and not by lowering the number of heads per plot. On the other hand, the weed reduced marketable yield by reducing both the average head weight and the number of heads per plot.
The feasibility of using liquid ammonium nitrate as a post-emergent weed control spray in cole crops was studied. The relative susceptibility of different weed species grown by themselves (1989) and with two crops (broccoli and onion; 1987) to ammonium nitrate (800 L ha⁻¹; 0, 7.5, 10, 15, 20 percent N) burning was investigated. The fertilizer controlled shepherd's-purse (Capsella bursa-pastoris), chickweed (Stellaria media), cudweed {Gnaphalium uliginosum), and redroot pigweed (Amaranthus retroflexus), but not lamb's-quarters, purslane (Portulaca oleracea), and annual bluegrass (Poa annua). Corn spurry (Spergula arvensis) varied in its tolerance. Although weed populations were reduced by 70 percent in 1987, the remaining weeds
competed so strongly with the onion and broccoli that the crop plants did not reach a harvestable size. The large initial weed population (799 plants m⁻²), the large number of tolerant weeds present, and the possible recovery of some of the susceptible weeds may all have been factors responsible for crop failure.
The effect of different shepherd's-purse densities (52 to 988 plants m⁻²) on the degree of ammonium nitrate (800 L ha⁻¹; 20 percent N) control in broccoli was also studied. The initial weed control achieved was reduced over time either because some weeds counted as dead had recovered or new plants were being recruited to the population through seed germination. Although the maximum density of shepherd's-purse plants that survived was 219 plants m⁻², these plants did not significantly reduce crop yield possibly because shepherd's-purse is not a very competitive species and all the surviving weeds had been damaged to varying degrees, further reducing their competitive ability.
The relative susceptibility of various crop cultivars to ammonium nitrate (800 L ha⁻¹; 0, 10, 15, 20 percent N) burning was also studied. In 1987, the growth rates of 'Lunet' (Brussels sprouts), ‘SGI' (broccoli), 'Elgon' (cauliflower), and 'Matra' (cauliflower) initially decreased but the plants recovered; they were largely unaffected in 1988. The growth rates of 'White Lisbon' (onion), 'Emperor' (broccoli), and 'Early Marvel' (cabbage) were largely unaffected in either year. Although some cultivars had shown initial signs of lower growth rates, there was no decrease in crop yield.
Leaf surfaces of tolerant and susceptible crop and weed species were examined by scanning electron microscopy to determine the basis of ammonium nitrate selectivity. Leaf surfaces of tolerant species were completely covered with a crystalline wax layer, while susceptible species had little or no epicuticular wax. Cellulose acetate was used to remove the epicuticular wax from cabbage leaves. The stripped leaves showed far greater ammonium nitrate retention and salt injury than unstripped leaves, demonstrating the importance of the epicuticular wax in providing protection against ammonium nitrate injury. Trichomes, observed on the leaf surfaces of some susceptible species, may further increase ammonium nitrate retention and, therefore, salt injury.Land and Food Systems, Faculty of
Graduate
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Donner, Horst. "The anthocyanins of red onions, Allium cepa L, extraction, characterization, complexation and stabilization." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq23285.pdf.
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Zuaznabar, Gardona Julio César. "Preparation and characterization of surfaces modified with carbon nano-onions. Biomedical and environmental applications." Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/670711.
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L’objectiu de la present tesi és la preparació y caracterització de superfícies modificades amb nanocebes de carboni (CNOs) per al desenvolupament de sistemes electrocatalítics i (bio)sensors electroquímics amb aplicacions biomèdiques i mediambientals. La primera part de la tesi està relacionada amb la dispersabilitat, l’estructura electrònica, la composició química de la superfície i les propietats electroquímiques de les CNOs. A la segona part es van explorar noves propietats electrocatalítiques i aplicacions en (bio)sensors electroquímics de les CNOs per a comprendre la seva relació amb l’estructura electrònica d’aquests materials. Els resultats exposen els avantatges d’incorporar les CNOs al disseny de sistemes electroquímics per millorar el seu acompliment analític. Altrament, aquest resultats podrien ser d’ajuda en la fabricació a mida de superfícies i dispositius amb propietats úniques per aprofitar al màxim el potencial de les CNOs i obrir un nou ventall de possibles aplicacions en àrees relacionades amb els mètodes electroanalítics i l’emmagatzematge electroquímic d’energia.El objetivo de la presente tesis es la preparación y caracterización de superficies modificadas con nanocebollas de carbono (CNOs) para el desarrollo de sistemas electrocatalíticos y (bio)sensores electroquímicos con posibles aplicaciones biomédicas y medioambientales. La primera parte de la Tesis está relacionada con la dispersabilidad, la estructura electrónica, la composición química de la superficie y las propiedades electroquímicas de las CNOs. En la segunda parte se exploraron nuevas características electrocatalíticas y aplicaciones en (bio)sensores electroquímicos de las CNOs para comprender su relación con la estructura electrónica de estos materiales. Los resultados aquí presentados ilustran las ventajas de incorporar las CNOs en el diseño de sistemas electroquímicos para mejorar su desempeño analítico. Además, dichos resultados podrían facilitar la fabricación a medida de superficies y dispositivos con propiedades únicas en las que se aproveche al máximo las potencialidades de las CNOs y para desarrollar nuevas aplicaciones en áreas como la de los métodos electroanalíticos y el almacenamiento electroquímico de energia.
The focus of the present thesis is to prepare and characterize surfaces modified with carbon nano-onions (CNOs) to develop electrocatalytic systems and electrochemical (bio)sensors for biomedical and environmental applications. The first part of the Thesis is a related to the dispersibility, electronic structure, surface chemical composition and electrochemical properties of CNOs. In the second part, novel electrocatalytic properties and electrochemical (bio)sensing applications of these materials were also explored to understand their relationship with the electronic structure, of CNOs. The results presented here illustrate the advantages of incorporating CNOs in the design of electrochemical systems to improve their performance. These results might help to fabricate tailor made surfaces and devices with unique properties to realize high potential of CNOs to the maximum and to open new application possibilities in areas such as electrochemical energy storage and electroanalytical methods.
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Budathoki, Kedar. "The effects of environmental conditions on the growth and development of onions in Nepal." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300012.
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Hall, Emily Anne. "Clusters and cosmic onions : a description of galaxy dynamics in the quasi-linear regime." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10057210/.
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This thesis investigates the dynamics of galaxies around clusters in the quasi-linear regime, with the ultimate aim of providing cluster mass constraints which can be combined with weak lensing measurements in order to perform tests of General Relativity. Dark matter simulations are populated with galaxies using a halo occupation distribution, and used to develop and test models which describe di↵erent aspects of galaxy dynamics around clusters. A heuristic analytical model is presented describing the infall profile of galaxies onto a cluster of given mass, which is shown to fit the simulations remarkably well on quasilinear scales. The velocity dispersion of galaxies in the simulations is also examined, and a model developed which describes how this e↵ect varies as a function of position relative to the cluster centre. These models of galaxy infall and velocity dispersion are combined to provide predictions of the cluster-galaxy redshift space correlation function, or cosmic onion, which show a relatively good agreement with the simulations. The cosmic onion model is used to obtain cluster mass constraints from redshift space distortions observed in the simulations, in order to demonstrate the robustness of this method. In this work the uncertainty on cluster mass was estimated with all other halo parameters fixed, and was found to be approximately 2% at the 2 confidence level for a halo mass of ⇠ 1013 Msolarh1. However in practice the accuracy of these constraints depends on how many free parameters are considered in the halo occupation distribution, as some are degenerate with the cluster mass. The techniques developed here can be applied to observational data from the upcoming generation of spectroscopic galaxy surveys, potentially improving constraints on the dynamic mass of clusters measured from redshift space distortions.
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Pöhnl, Tobias [Verfasser]. "Influence of varietal onion composition on yield and quality of onion juice / Tobias Pöhnl." Düren : Shaker, 2020. http://d-nb.info/1217164197/34.
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Mullin, Joseph A. "Onion skins : a fall collection." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/845933.
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The poems in this collection are poems of discovery and explanation. They are the recordings and insights of what it means to be a young male in the North American Midwest in the year 1992. Some are memories of what was or what should have been. Some of the poems are attempts to give meaning to what is, or more importantly, to give meaning to the "who" that is becoming. The majority of the poems deal with opposing tensions, especially between society and the individual, and between knowing and the unknown. In almost all the poems there are two forces pulling at the narrator, and there is an axis between the poles which must remain balanced.The need for balance becomes a central element because of the narrative influence in the poems. They represent a coming of age and contain the myriad viewpoints struggling for recognition at such a time. Some of the poems seem to detail this process; others seem to be results of it. In either case, the poems try to capture the emotive and cognitive quality of a moment.The frequent tension between the conflicting emotive and analytical qualities often results in an ambiguity in the poems. This collection is not so much a finished piece of work as a still continuing process. I hope this questioning attitude is plain in the work and is shared by the reader, for it is a major quality of the poems.Ball State UniversityMuncie, IN 47306Department of English
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Brice, John R. "Investigations into onion skin quality." Thesis, Cranfield University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320261.
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Hagler, J. R. "Hybrid Onion Seed Trial, 1987." College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/214155.
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Successful seed production of open pollinated onion (Allium cepa L.) is difficult in Arizona. Providing adequate pollen transfer by honey bees (Apis mellifera) to ensure adequate seed set is a problem often encountered. Honey bees discriminate between onion cultivars. Onion flowers appear to be less attractive to honey bees than flowers of most competing plants. Bees may neglect the crop, particularly if another highly attractive plant species is in bloom. This honey bee discrimination has led to poor onion seed yields. This report compares seed production among five onion cultivars in Tucson, Arizona.
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Umeda, K., C. Fredman, B. McGrath, and T. Pettigrew. "Dry Bulb Onion Variety Trial." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/221448.
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Yacoub, M., L. J. Clark, and J. L. Stroehlein. "Effects of Soil Amendments on Crusting, Seedling Emergence and Yields of Onions, Tomatoes and Peppers." College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/221239.
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Studies were carried out at the Safford Agricultural Center using some soil amendments as anti-crusting agents. The results are promising in terms of improved stands on soils subject to crusting. Additional research is needed in order to determine proper rates which will reduce crusting without being toxic to the emerging seedlings.
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Kimbirauskienė, Rasa. "Botrytis spp. infekcijos prognozavimas ropiniuose svogūnuose taikant internetinę „iMETOS®sm“ sistemą." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120613_114311-95534.
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Magistratūros studijų baigiamajame darbe įvertintas ir pritaikytas Botrytis spp. infekcijos prognozavimo modelis ropiniuose svogūnuose apsaugai nuo ligų vegetacijos metu.
Darbo objektai – ropiniai svogūnai (Allium cepa L.); ligos sukėlėjai - kekerinis lapų dėmėtumas (Botrytis squamosa) ir lapų taškuotoji dėmėtligė (Botrytis cinerea); internetinė „iMETOS®sm“ prognozavimo sistema (Botrytis spp. infekcijos prognozavimo modelis).
Tyrimo metodai: tiriamas meteorologinės stotelės „iMETOS®sm“ Botrytis spp. infekcijos prognozavimo modelių pritaikymas ropiniuose svogūnuose. Tirti dviejų Botrytis rūšių sukeliamų ligų prognozavimo modeliai: 1) Botrytis squamosa infekcijos modelis; 2) Botrytis cinerea rizikos modelis. Mikologiniams tyrimams ėminiai surinkti nuo Botrytis grybais pažeistų svogūnų vegetatyvinių dalių vystymosi tarpsniu ir tirti taikant vizualinį – simptomatinį, drėgnų kamerų, sėjimo į Petri lėkšteles, mikroskopavimo metodus. Išskirti izoliatai identifikuoti iki rūšies, remiantis kolonijų kultūrinėmis ir morfologinėmis savybėmis bei lyginant su literatūros duomenimis, naudojant apibūdintojus (Domsch ir kt., 1980, p. 859). Tyrimams pasirinktos dvi apsaugos sistemos: pagal faktinį ligos simtomų aptikimo laiką ir pagal „iMETOS®sm“ Botrytis spp. infekcijos svogūnuose modelio parodymus.
Darbo rezultatai. Botrytis squamosa infekcijos prognozavimo modelis parodė, kad svogūnų kekeriniam dėmėtumui plisti palankios sąlygos abiejuose tirtuose rajonuose susidarė birželio–rugpjūčio mėn... [toliau žr. visą tekstą]The master's degree thesis is evaluated and applied to the Botrytis spp. infection in onion forecasting model for the protection against disease during the growing season. Object of the work - onion (Allium cepa L.) pathogens - Botrytis leaf blight discoloration (Botrytis squamosa) and Botrytis leaf spot in (Botrytis cinerea), an online „iMETOS®sm” Forecasting System (Botrytis spp. infection prediction model). Methods of the work: studied meteorological station „iMETOS®sm” Botrytis spp. infection forecasting models use onion. To explore the two types of diseases caused by Botrytis forecasting models: 1) Botrytis squamosa infection model, 2) risk model Botrytis cinerea. Mycological examination of samples collected fungi Botrytis damaged vegetative parts of the onion stage of development and exploration through visual - symptomatic, moist chambers, seeding in petri dishes, microscopy techniques. Distinguish isolates identified to species based on cultural and morphological colony characteristics and comparison with literature data using apibūdintojus (Domsch et al., 1980, p. 859). For this work, the two security systems based on the actual detection of the disease symptoms at the time and under „iMETOS®sm” Botrytis spp. evidence of infection onion model. The results of work. Botrytis squamosa infection prediction model showed that the onion gray mold to spread favorable conditions in both regions studied occurred between June and August. Kaunas district. B... [to full text]
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Chope, Gemma Amy. "Understanding the mechanisms behind onion bulb dormancy in relation to the potential for improved onion storage." Thesis, Cranfield University, 2006. http://hdl.handle.net/1826/1501.
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Onion (Allium cepa L.) is the most economically important Allium crop. Onion
cultivars adapted for growth in temperate regions require long days for bulb initiation, so the summer crop is stored over-winter. Deterioration in store is largely due to resumption of growth. Extended storage of onions is currently dependent on the synthetic sprout
suppressant maleic hydrazide, whose future use is uncertain due to pressure to reduce
residues in foods.
Abscisic acid (ABA) has previously been linked with dormancy in a relative of
onion (A. wakegi). Bulb ABA concentration in three onion cultivars (viz. Renate, Ailsa
Craig and SS1) with contrasting storage lives declined exponentially during controlled atmosphere (CA – 3% CO2, 5% O2; 2°C) storage at the same rate in each cultivar.
Sprouting occurred at a minimal ABA concentration (ca. 50-120 ng g-1 DW). It was
proposed that extended periods of high concentrations of ABA may delay sprouting.
An ABA analogue (PBI-365) and exogenous ABA, were applied as preharvest foliar sprays (cvs. Renate, Carlos, Dinaro, Hysam, Red Baron and SS1), or as postharvest bulb soaks (cv. Hysam) with the aim of increasing endogenous ABA concentration and, thereby, extending the storage period. Endogenous bulb ABA concentration was not affected. Bulb ABA concentration again decreased during storage at a range of temperatures (4, 12 and 20°C) and sprouting occurred at minimal ABA concentration (ca. 75-150 ng g-1 DW). After the onset of sprouting, ABA concentration increased again, probably due to synthesis by the sprout. The concentration of certain carbohydrates has
been linked with storage potential. No straightforward relationship between ABA and
non-structural carbohydrate (NSC; fructose, glucose, sucrose and fructans) metabolism
could be determined. It was therefore postulated that ABA is more likely to play a role in mediating cell elongation rather than cell division, or that minimal ABA concentration could be a trigger for remobilisation of carbohydrates.
Controlled atmosphere (CA) is used to extend storage life of onions; however, shelf-life can be compromised. The effects of the transition between CA (3 % CO2, 5 %
O2; 2°C) and air storage on ABA concentration, quality characteristics, respiration rate(RR) and NSCs in three onion cultivars (viz. Renate, Carlos and SS1) were investigated. The RR of the short storing cultivar, SS1, was greatest by ca. 0.5-fold. The RR increased on removal from CA storage, with no accompanying decrease in carbohydrate
concentration, indicating that the increased RR may have been a transient stress response.
Storage of onions cv. SS1 for three weeks in air, followed by three weeks CA was as
effective in suppressing sprout growth as six weeks continuous CA storage. Bulb ABA
concentration decreased significantly between the time of harvest and after curing.
Therefore the current practice of curing onions for extended periods at high temperatures could be reducing bulb ABA concentration, and therefore storage life.
The literature concerning the role of ethylene in onion storage is limited and
conflicting. The effect of 1-methylcyclopropene (1-MCP; an ethylene perception inhibitor) on sprout growth in onions cv. SS1 stored at a range of temperatures (4, 12 and 20°C) was investigated, along with quality characteristics, NSCs and ABA. Sprout
growth was reduced in onions treated with 1-MCP and stored at 4 or 12°C, but not at
20°C. Approximately 2-fold greater concentrations of sucrose, glucose and fructose were maintained in 1-MCP-treated bulbs stored at 12°C as compared with untreated bulbs. It appeared that 1-MCP reduced carbohydrate metabolism.
Both ethylene and ABA are highly likely to impact significantly on onion storage
life. The results are discussed in relation to the potential to influence storage life by
changes in horticultural practices, including the recommendation to re-evaluate the curing and drying protocol, and to investigate the possibility of delaying the start of CA storage.
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Kamoi, T. "Developing an optimal method for producing a tearless onion." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1008.
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People experience the irritating tearing and burning sensation of lachrymatory factor (LF, propanthial S-oxide) when cutting or chopping onion bulbs. LF is produced by lachrymatory factor synthase (LFS) specifically from 1-propenyl sulfenic acid, a breakdown product of trans-1-propenyl-L-cysteine sulfoxide (1-PRENCSO) by alliinase. This thesis describes strategies to produce a tearless onion by using RNA interference (RNAi) silencing. To determine whether a gene silencing cassette can silence lfs gene transcripts from onion (Allium cepa L.), a crop recalcitrant to genetic transformation, a gene silencing assessment system was developed by using a model plant as a host for the gene of interest. Tobacco (Nicotiana tabacum) plants transgenic for LFS enzyme activity from onion were first produced by introducing a CaMV 35S-onion-lfs gene construct. These plants were then subjected to a second transformation with an RNAi construct directed against the lfs gene sequence. LFS enzyme activity assay showed that the transgenic plants, containing both the lfs gene and the RNAi construct, had significantly reduced LFS activity. This observation was supported by Western analysis for the LFS protein and further validated by quantitative RT-PCR analysis that demonstrated a significant reduction in the lfs transcript level in the dual transformants. This work demonstrated that the RNAi construct is a suitable candidate for the development of a tearless onion. This model plant RNAi system has wide reaching applications for assessment and targeting of plant secondary pathway genes, from poorly studied or recalcitrant plant species, that are important in pharmacological, food and process industries. The functional RNAi vector identified in the model system was transformed into onion. Endogenous lfs transcript levels were successfully reduced by up to 43-fold in six transgenic lines. In consequence, LFS enzyme activity was decreased by up to 1573-fold and this observation was supported by Western analysis for the LFS protein. Furthermore, the production of the deterrent LF upon tissue disruption was reduced up to 67-fold. Subjective olfactory assessment of silenced lines indicated that the pungent odour given off by the leaf and bulb material was much reduced compared with that of non-transgenic counterparts, and that this was replaced by a sweeter milder onion odour. A novel colorimetric assay demonstrated that this silencing had shifted the 1-PRENCSO breakdown pathway so that by reducing LFS protein, more 1-propenyl sulfenic acid was converted into di-1-propenyl thiosulfinate. A consequence of the raised thiosulfinates levels was a marked increase in the downstream production of a non-enzymatically produced zwiebelane isomer that has never previously been identified, and other volatile compounds, di-1-propenyl disulfides and 2-mercapto-3,4-dimethyl-2,3-dihydrothiophenes, which had previously been reported either in small amounts or had not been detected in onions. These raised volatile sulfur compounds provide an explanation for the unique flavour notes of the LF reduced onion and are predicted to have health benefits akin to those found in garlic. These results demonstrated that silencing of LFS enzyme activity by introducing an RNAi construct directed against the lfs gene sequence simultaneously reduced levels of the deterrent LF and increased the desirable thiosulfinates in onions.
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Clark, Lee J., Fred Harper, and L. Max Thatcher. "Onion Variety Trial, Safford Agricultural Center." College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/214114.
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In response to the request for alternative crop production information, 92 varieties of long-day onions were planted on the Safford Agricultural Center. Many varieties performed well, with the top variety yielding almost 480 cwt per acre. It appears that onions can be a viable alternative crop for some farmers in the upper Gila valley.
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Rethwisch, Michael D. "2001 Yield Response of Processing Onions in the Palo Verde Valley Treated with AuxiGro® WP." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/214951.
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Processing onions were treated with AuxiGro in spring 2001. Applications were applied at four and 7.5 weeks prior to harvest. A single application of 4 oz. product/acre at either four or 7.5 weeks prior to harvest increased yield by approximately 0.7 tons/acre. Two applications resulted in a 1.3 tons/acre yield increase. Differences noted were not statistically different, but the two application treatment provided an increased net return of approximately $95/acre.