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Dissertations / Theses on the topic 'Perennialism'
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1
Pettersson, Martin. "Grundfilosofiska ideér och pedagogisk verklighet : En jämförelse mellan behöriga och obehöriga lärare." Thesis, Högskolan Dalarna, Pedagogiskt arbete, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3074.
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I min uppsatts så undersöker jag om det finns någon uppenbar pedagogisk skillnad mellan behöriga och obehöriga lärare. I undersökningen så deltog två outbildade och två utbildade lärare. Jag gör undersökningen genom grundfilosofiskt perspektiv. Jag börjar med att ge lite statistik på hur fördelningen har varit mellan behöriga och obehöriga lärare från 1990-talets början till en början in på 2000-talet. Redovisar sedan fyra grundfilosofier essentialism, perennialism, progressivism och rekonstruktionism. Efter detta redovisar jag mina intervjuer och filminspelningar samt tolkar och redovisar dessa. Jag kommer framtill att jag inte kan se någon uppenbar skillnad i min intolkning av de olika lärarna vare sig de är utbildade eller inte.
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Fabbri, Renaud. "Frithjof Schuon the shining realm of the pure intellect /." Oxford, Ohio : Miami University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1175881809.
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Brandin, Hannah. "Kunskap för framtiden? : En kvalitativ undersökning om tidigare gymnasieelevers upplevelser av religionsundervisningen i gymnasieskolan." Thesis, Högskolan i Halmstad, Akademin för lärande, humaniora och samhälle, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-39204.
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Denna uppsats undersöker i vilken utsträckning tidigare gymnasieelever upplever att religionsundervisningen i den svenska gymnasieskolan har varit förberedande för ett liv i samhället efter avslutade studier. Vidare undersöker uppsatsen även tidigare gymnasieelevers upplevelser av religionsundervisningen som betydelsefull och bristfällig. För att erhålla ett resultat har fyra semistrukturerade intervjuer med tidigare gymnasieelever som läst religionskunskap 1 & 2 utefter Gy 11 gjorts. För att visa på i vilken utsträckning religionsundervisningen har varit förberedande för informanterna har insamlat material analyserats utifrån en flerdimensionell utbildningsfilosofisk karta vilken anger hur lärarens spektrum av urval och innehåll är inordnat i flera spänningsfält av huruvida undervisningen ska syfta till att förvalta en tradition, ett kulturarv, eller om den istället ska syfta framåt och förbereda för framtiden. Undersökningen visar att religionsundervisningen i stor utsträckning har varit förberedande för ett liv i samhället efter avslutade studier för informanterna och att det innehåll och de undervisningsmetoder som informanterna upplevde vara bristfälliga i hög grad går att koppla till en åstundan efter en undervisning där diskussion, samtal, projekt- och temaarbeten, konfliktfyllda frågor, grupparbeten och problemlösning är centrala aktiviteter. Vidare visade undersökningen på en åstundan efter problembaserad, reflekterande, samtidsrelevant och problemlösande undervisning där elevernas erfarenheter och intressen är i fokus.
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Lundmark, Fredrik. "Skolans syfte mellan 1965 & 1994 : En problematisering av synen på gymnasieskolan utifrån ett utbildningsfilosofiskt perspektiv." Thesis, Umeå University, Historical Studies, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1186.
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Arbetet bygger på ett ifrågasättande av synen på gymnasieskolans olika delar mellan åren 1965 och 1994 som idémässigt enhetliga med ett gemensamt syfte och utveckling. Uppsatsens syfte är att problematisera denna syn utifrån ett utbildningsfilosofiskt perspektiv. Syftet konkretiseras genom två frågeställningar, den första frågeställningen behandlar vilka idéer som uttrycks i skolans kursplaner, till vilken utbildningsfilosofi idéerna kan kopplas och hur de förändras under den undersöka tidsperioden. Den andra frågan behandlar vilka likheter och skillnader i utbildningsfilosofisk grund som finns mellan de olika ämnenas kursplaner under tidsperioden. Källmaterialet bearbetas genom textanalys i form av idéanalys för att på så sätt utvinna de idéer som utrycks. Därefter används idealtyper för att kategorisera idéerna till dess utbildningsfilosofiska grund. Slutligen görs en jämförande analys för att analysera likheter och skillnader mellan de undersökta ämnenas kursplaner. Resultatet av analyserna visar på att det finns vissa gemensamma drag gällande utbildningsfilosofisk grund och utveckling under den behandlade tidsperioden, men att skillnaderna är fler än likheterna. En av de slutsatser man kan dra av resultatet är att gymnasieskolan under tidsperioden mellan åren 1965 och 1994 hade ett splittrat syfte. De olika ämnena byggde inte på samma utbildningsfilosofiska grund och därmed syftande ämnena till att påverka eleven på olika sätt.
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Metcalf, Charlotte Jessica Eland. "Evolutionary demography of monocarpie perennials." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416378.
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Abod, Sheikh Ali. "Growth and establishment of woody perennials." Thesis, Imperial College London, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364051.
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Cerveny, Christopher B. "Stock plant management of tropical perennials." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0015781.
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DeGomez, Tom. "Perennials for Northern Arizona above 6000 Foot Elevations." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/144761.
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12 pp.This article provides information about perennials in Northern Arizona. It describes planting them, preparing the soil, irrigation, mulching, fertilizing, etc.. It lists out many of the perennials and gives information about each of their growing conditions and their use.
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Braun, Hattie, and Tom DeGomez. "Perennials for Northern Arizona above 6000 Foot Elevations." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/239573.
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Harris, William Kevin. "Increasing the overwintering survival of container-grown perennials." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/35746.
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Container grown perennials are a popular product offered by nurseries and greenhouses and included in their production but little research has been reported on proper overwintering techniques for herbaceous perennials and ornamental grasses.
In the first experiment rooted liners of Pennisetum alopecuroides, Pennisetum â Hamelnâ and Pennisetum â Little Bunny,â were potted. Treatments included, utilizing two overwintering covers, two fertilizer rates (low or high) and two substrate moisture contents (wet or dry). Covering with either a double layer of Dewitt N-Sulateâ ¢ insulation fabric or a double layer of Dewitt N-Sulateâ ¢ insulation fabric and a single sheet of 4 mil white polyethylene plastic on top of the insulation fabric, wet substrate treatments, low fertility rates and combinations of both, improved survival and vigor for all three tested Pennisetum species and cultivars.
In the second experiment, rooted liners of P. alopecuroides, P. â Hamelnâ and P. â Little Bunny,â were potted. Treatments included, two transplanting times (young or old), two fertilizer rates (low or high) and two substrate moisture contents (wet or dry) at the UHC and Poplar Ridge Nursery (Montross, VA) (PR). Vigor was improved for P. alopecuroides (at PR) and P. â Little Bunnyâ (at both locations) with the young transplanting time.
In the third experiment, older plant material of P. alopecuroides, P. â Hamelnâ and P. â Little Bunny,â were subjected to fertility treatments of no additional fertilizer or top-dressed at a low, medium or high rate . A high fertility rate reduced survival and vigor for P. â Little Bunny.â
In the fourth experiment rooted liners of Echinacea purpurea â Hot Papaya,â Echinacea purpurea â Milkshake,â Gaillardia x grandiflora â Gallo Peach,â Heuchera x villosa â Pistache,â Heuchera x villosa â Brownies,â P. alopecuroides, P. â Cassian,â P. â Hamelnâ and P. â Little Bunny,â were potted and overwintered at the UHC or Poplar Ridge Nursery (Montross, VA) (PR) or Riverbend Nursery, Inc. (Riner, VA) (RB). Treatments included, utilizing two overwintering covers, two fertilizer rates (low or high) and two substrate moisture contents (wet or dry). Vigor at the UHC, was reduced with the high fertility rate for E. â Hot Papayaâ and H. â Brownies.â A double layer of Dewitt N-Sulateâ ¢ insulation fabric and white polyethylene plastic on top of the cover, in combination with the wet substrate moisture treatment improved vigor of E. â Hot Papaya.â A double layer of Dewitt N-Sulateâ ¢ insulation fabric in combination with the wet substrate moisture content and the high fertility rate reduced P. â Cassianâ vigor. No overwintering cover reduced P. â Hamelnâ vigor. No overwintering cover and the high fertility rate reduced P. â Little Bunnyâ vigor. Vigor at PR was improved with the high fertility rate for E. â Milkshake,â G. â Gallo Peachâ and H. â Brownies.â At RB, a double layer of Dewitt N-Sulateâ ¢ insulation fabric in combination with the low fertility treatment and no cover in combination with the high fertility treatment reduced vigor for E. â Milkshakeâ and P. â Little Bunny,â respectively. No cover in combination with the wet substrate moisture treatment reduced vigor for G.â Gallo Peach.âMaster of Science
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Dimke, Kelley C. "Effect of overwintering systems on 30 species of herbaceous perennials." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299774589.
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Deeter, Laura M. "Sodium Chloride tolerance of selected herbaceous perennials and the effects of Sodium Chloride on osmotic adjustment and ionic uptake in three species of herbaceous perennials /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486402288261395.
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Cameron, R. W. F. "Low temperature stress in woody perennials with special reference to rhododendron." Thesis, University of Strathclyde, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395132.
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Mortimer, Simon Richard. "The control of population size of sparse perennials in chalk grassland." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319820.
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DiSabato-Aust, Tracy M. "Hardiness of herbaceous perennials and its implication to overwintering container grown plants." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1300117596.
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Mitsui, Yuki. "Ecological speciation at riparian habitats in perennials of the genus Ainsliaea (Asteraceae)." Kyoto University, 2011. http://hdl.handle.net/2433/142288.
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Kyoto University (京都大学)0048
新制・課程博士
博士(人間・環境学)
甲第16160号
人博第543号
新制||人||132(附属図書館)
22||人博||543(吉田南総合図書館)
28739
京都大学大学院人間・環境学研究科相関環境学専攻
(主査)准教授 瀬戸口 浩彰, 教授 加藤 眞, 准教授 市岡 孝朗
学位規則第4条第1項該当
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Johansson, Mikael. "The circadian clock in annuals and perennials : coordination of Growth with Environmental Rhythms." Doctoral thesis, Umeå universitet, Institutionen för fysiologisk botanik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-35870.
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Since the first signs of life on planet earth, organisms have had to adapt to the daily changes between light and dark, and high and low temperatures. This has led to the evolution of an endogenous time keeper, known as the circadian clock. This biological timing system helps the organism to synchronize developmental and metabolic events to the most favorable time of the day. Such a mechanism is of considerable value to plants, since they in contrast to animals cannot change location when the environment becomes unfavorable. Thus is the ability to predict coming events of central importance in a plants life. This thesis is a study of the molecular machinery behind the clockwork in the small weed plant Arabidopsis thaliana as well as its close relative perennial; the woody species Populus. We have characterized a novel component of the circadian clock, EARLY BIRD (EBI). EBI is involved in transcriptional and translational regulation, via interaction with the known post-translational clock regulator ZEITLUPE (ZTL). In Populus, we describe the role of the circadian clock and its components with respect to entry and exit of dormancy and show that gene expression of the Populus LATE ELONATED HYPOCOTYL (LHY) genes are crucial importance for freezing tolerance and thereby survival at high latitudes. Furthermore, the input to the Populus clock is mediated via the phytochrome A (phyA) photoreceptor.Liv på jorden har alltid behövt anpassa sig till de dagliga växlingarna mellan främst ljus och mörker. Detta har lett till evolutionen av en intern, biologisk klocka, känd som den circadianska klockan, efter latinets ”circa diem”, som betyder ”ungefär en dag”. Denna inre klocka hjälper organismer att styra biologiska processer till den tid på dygnet som är mest gynnsam för deras utveckling och överlevnad. Denna mekanism är av stort värde för växter, eftersom de inte kan söka skydd på mera lämpliga platser om de blir utsatta för olika former av stress. Det gör att förmågan att förutse kommande händelser är av yttersta vikt för växter. Denna avhandling är en studie av det molekylära nätverk som styr denna biologiska klocka i den lilla örtplantan Arabidopsis thaliana (backtrav), och den besläktade träd-arten Populus (hybrid-asp). Vi har karaktäriserat en ny komponent i den circadianska klockan i Arabidopsis, EARLY BIRD (EBI). EBI är involverad i transkriptionell och translationell reglering av klockan, via interaktion med den kända post-translationella klock-regulatorn ZEITLUPE (ZTL). I Populus har vi beskrivit den interna klockan och dess roll i processer som invintring, vinterdvala och återstart av tillväxt. LATE ELONATED HYPOCOTYL (LHY) generna i Populus är avgörande för förvärv av köld-tolerans och således överlevnad på högre latituder. Dessutom har vi visat att signaler till den circadianska klockan i Populus är medierade via fotoreceptorn phytochrome A (phyA).
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Kerkhoff, Karen Leigh. "Effects of defoliation on the cultivated strawberry (Fragaria X ananassa Duch.)." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45799.
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Using 'Redchief' (Junebearer) and 'Tribute' (dayneutral) cultivars, greenhouse and field studies were conducted to determine the effects of defoliation on photosynthesis, growth and yield of the strawberry. From preliminary photosynthesis experiments it was found that both 'Redchief' and 'Tribute' strawberry leaves reached maximum net photosynthesis (Pn) concurrently with full leaf expansion at approximately 8 to l0 days and 4 to 5 days, respectively, after unfolding. By exposing the plants to increasing irradiance it was determined that these cultivars were light saturated at 600 to 700)Ï molâ ¢m-2s-1. Neither cultivar showed a consistent diurnal pattern when Pn was monitored hourly over two consecutive days.
Master of Science
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Beckort, Richard. "Evaluation of Three Coverings for the Overwintering of Container Grown Herbaceous Perennials in Kentucky." TopSCHOLAR®, 1987. https://digitalcommons.wku.edu/theses/2153.
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The purpose of this study was to evaluate three coverings for overwintering twelve varieties of container grown herbaceous perennials under Kentucky conditions. The twelve perennial varieties were started from seed in the spring and had been moved to one gallon containers by fall. In the first week of December, three blocks of containers were covered with one of the following: one layer of 4 mil, milky copolymer; one layer of quarter inch microfoam and one layer of milky copolymer; a sandwich of two layers of milky copolymer with 6 inches of wheat straw between them; the remaining block was left uncovered as a check.
The perennials were uncovered in the spring, observed, and evaluated. The single layer of copolymer and the microfoam and copolymer treatments had the most new growth. The growth under the copolymer and straw sandwich method was elongated and white. Only three containers in the uncovered treatment showed signs of regrowth.
The microfoam and copolymer and the single layer of milky copolymer proved to be the best coverings for the over - wintering container grown herbaceous perennials in Kentucky.
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Cunliffe, R. N. "The role of interactions between perennials and annuals as determinants of annual plant community structure." Bachelor's thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/27663.
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Kingsley-Richards, Sarah. "Influence of Plant Age, Soil Moisture, and Temperature Cylcing Date on Containter-Grown Herbaceous Perennials." ScholarWorks @ UVM, 2011. http://scholarworks.uvm.edu/graddis/122.
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Perennial growers overwintering plant stock require information to assist in deciding which containerized plants are most likely to successfully overwinter. Three studies on container-grown herbaceous perennials were conducted to examine the influence of plant age, soil moisture, and temperature cycling date on cold hardiness. In January, plants were exposed to controlled freezing temperatures of -2, -5, -8, -11, and -14C and then returned to a 3-5C greenhouse. In June, plants were assessed using a visual rating scale of 1-5 (1 = dead, 3-5 = increasing salable quality, varying by cultivar) and dry weights of new growth were determined. Controlled freezing in November and March were also included in the third study. In the first study, two ages of plants were exposed to controlled freezing temperatures in January. For Geranium x cantabrigiense 'Karmina', age had no effect on either rating or dry weight in one study year. In two Sedum 'Matrona' study years, age had no effect on dry weight but ratings were higher for older plants than younger plants in the first year and higher for younger plants than older plants in the second year. In two Leucanthemum x superbum 'Becky' study years, age had an effect on both rating and dry weight which were both generally higher for younger plants than older plants. In the second study, plants were maintained in pots at two different soil moisture levels prior to exposure to controlled freezing temperatures in January. Coreopsis 'Tequila Sunrise' and Carex morrowii 'Ice Dance' showed no effect on either rating or dry weight from soil moisture level. Soil moisture level had no effect on dry weight but ratings were higher for Geranium x cantabrigiense 'Cambridge' “wet” plants and for Heuchera 'Plum Pudding' “dry” plants. Carex laxiculmus 'Hobb' (Bunny Blue™) soil moisture level had an effect where dry weight was higher for “dry” plants. Means at were of salable quality for Geranium and Heuchera at all temperatures and Carex laxiculmus at temperatures above -11C. The effects of soil moisture level on Carex oshimensis were inconclusive. In the third study, during November, January, and March, plants were subjected to temperature cycling treatments prior to exposure to controlled freezing temperatures. Geranium x cantabrigiense 'Cambridge' were more tolerant of both temperature cycling and freezing temperatures in January and an increased number of cycles in November had an advantageous effect. Sedum 'Matrona' were more tolerant of temperature cycling and freezing temperatures in January and an increased number of cycles in March had an advantageous effect. Leucanthemum x superbum 'Becky' were more tolerant of temperature cycling in January in the second year of the study and an increased number of cycles in November had an advantageous effect in the first year and in all months in the second year. Overwintering younger container-grown plants is likely to result in more growth and higher quality following exposure to freezing temperatures. Effects of soil moisture level on overwintering container-grown plant growth and quality are cultivar-specific and a general effect could not be established in these studies. Overwintering container-grown plants are likely to be hardier in January and slight temperature cycles prior to exposure to freezing temperatures generally increase hardiness.
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Lindgren, Jenny. "Ekologiska perenner - Lokalt och globalt : En Intervju- och Litteraturstudie." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-18538.
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Abstract The customer demand for ecological products has increased in recent years, within the garden industry this mainly concerns herbs and other edible plants. The organic trend is increasing and more people are aware of the environment and want to take responsibility for it through their purchases for their garden as well. In this essay the aim is to investigate customer demand and the possibility of selling organic perennial plants in eight garden centres on the Åland islands and in Gävle/Sandviken. I include two garden centres with an organic profile to get a wider point of view. I investigate the global market for organic perennials and look further into existing certification standards on the Swedish market today. The methods I have been using are interviews and a literature study. The study shows that the experienced demand for organic perennials is small in both of my investigated groups. The biggest motivation for starting to sell organic perennials would be to find a supplier of these plants and that more customer would ask for them. The certification systems on the Swedish market today do not concern specifically organic perennials; there is a lack of rules of conduct. In USA the demand for organic perennials has increased in recent years. Several nurseries with an organic profile have opened and programs for guidance of organic growers have been founded. In Germany the production of organic perennials is small and organic certification is lacking. In both countries further research on the market for organic perennials is suggested.Sammanfattning Utbudet och efterfrågan på ekologiska produkter har under de senaste åren ökat. Detta gäller främst livsmedel men trenden kan också ses beröra växter. De ekologiska växterna tenderar främst att vara kryddor och ätbara växter, inte prydnadsväxter. Samband kan ses mellan konsumenternas medvetenhet om miljöfrågor och efterfrågan på ekologiska växter. Syftet med uppsatsen är att i huvudsak undersöka trädgårdshandeln i Gävle/Sandviken och på Åland och dess syn på möjlighet till försäljning av ekologiska perenner samt undersöka internationella erfarenheter kring produktion och efterfrågan, och att studera utvalda svenska kvalitetssystem för perenna växter. Frågeställningarna berör efterfrågan och inställningen till ekologiska perenner hos de utvalda handelsträdgårdarna, ekologiska odlares perspektiv, existerande certifieringssystem och den internationella marknaden med fokus på USA och Tyskland. Som metod använder jag mig av intervjuer samt litteraturstudie. Jag har intervjuat totalt tio stycken trädgårdshandlare, varav två stycken med ekologisk profil. På Åland och i Gävle/Sandviken är den upplevda efterfrågan på ekologiska perenner hos de utvalda handelsträdgårdarna liten och ingen av dem säljer ekologiska perenner. Trädgårdshandlarna är motiverade till att börja sälja ekologiska perenner om någon leverantör erbjuder sådant växtmaterial och ifall efterfrågan ökar. De två handelsträdgårdarna med ekologisk profil upplever inte heller någon stor efterfrågan på ekologiska perenner. De levererar inte perenner till andra återförsäljare. I USA har efterfrågan och utbudet på ekologiska perenner ökat. Den största kundgruppen är unga, miljöintresserade personer. Det har startats program för att hjälpa ekologiska odlare av prydnadsväxter. Certifierade plantskolor finns. I Tyskland består produktionen av prydnadsväxter av en liten andel ekologiska växter. Ekologisk certifiering för produktionen saknas. I både USA och Tyskland föreslås vidare forskning kring ekologiska perenner och deras efterfrågan. I Sverige saknas ett specifikt framtaget certifieringssystem för ekologiska perenner. GRO, E-plant och Svenskt Sigill omfattar inte ekologisk odling och certifiering av sådana växter. KRAVmärkningen omfattar även odling av perenner, men det saknas regler och förhållningssätt speciellt utvecklat för odling av perenner.
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Dubois, Jean-Jacques Bernadette. "Plant Level Response of Seven Herbaceous Perennials to Diurnal Temperature Cycling and Sub?diurnal Temperature Variation." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-01032005-152319/.
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Climate warming has not affected day and night symmetrically: daily temperature range (DTR) is narrowing, as daily average temperature (DAT) increases. The potential impacts of combined DAT and DTR variation on plants are unknown. Four experiments were conducted to assess such impacts. In the first two, plants of seven herbaceous perennial taxa were exposed to 18 combinations of day and night temperature for 50+ days. Effects on total plant dry weight (DW) were analyzed with the aid of a thermodynamic model, modified to include two temperature dimensions. Results showed that the effects of temperature on DW cannot be accounted for by variation in either DAT or DTR alone, and that their magnitude is equivalent. The greatest effect of variation in DTR on DW was on plants growing closest to their optimal DAT. Time?to?event data analysis methods were used to determine the relative effects of DAT and DTR on anthesis and death in two taxa. Effects of day and night temperature could be separated for both events, but were almost entirely subsumed into DAT. Although effects of DTR were significant, they only became meaningful at the extremes. Results suggest changes in DTR are a lesser concern for anthesis and survival than for gross productivity. Two experiments were then conducted to assess the effect on DW of temperature variation within each of the two phases of the diurnal cycle. Plants of Delphinium × cultorum and Rudbeckia fulgida var. sullivantii L. were grown for 40 days under 28 temperature regimes all resulting in cycles of 12-h days/12-h nights at average either 15/15°C, or 25/15°C. There were 14 regimes for each combination, during which temperature varied between 5 and 35 °C every 4 hours. Temperature varied during the light period in the first experiment, and the dark period in the second. Few significant differences in DW were found among regimes for either taxon, and they did not produce a consistent pattern. Results indicate that over season?long durations, effects of sub?diurnal variation on gross productivity are far less consequent than those of diurnal variation.
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Gaol, Mangadas Lumban. "Ecological study of plant species at Sandford Rocks Nature Reserve (SRNR)." Curtin University of Technology, Department of Environmental Biology, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=13955.
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The ecology of plant species at Sandford Rocks Nature Reserve (SRNR) was studied. The study site is an important nature reserve that contains relatively undisturbed natural vegetation. It has a mosaic of exposed granite rocks, scrublands and woodlands. The study involved: a description of the structure and composition of the vegetation; the population characteristics of selected Acacia species; aspects of reproduction in Acacia; germination and seedling characteristics of some Acacia and grass species that dominate the reserve; the effect of seed size on germination and seedling characteristics; and, the relationship of seed size to seed coat thickness in selected Acacia species. Five different areas were studied using the point centered quarter method to sample the woody perennial species. Thirteen Acacia species were examined for reproduction characteristics; and in 2 selected Acacia species, the effects of phyllode and/or inflorescence removal on reproduction was investigated. Germination tests were conducted to identify germination characteristics in 8 Acacia and 7 grass species dominant at SRNR. The possible effects of variation in seed size on germination; seedling characteristics; and, seed coat thickness were investigated in Acacia fauntleroyi and Acacia prainii. A total of 85 species from 20 families of woody perennials were collated. All areas were dominated by the Myrtaceae, Mimosaceae and Proteaceae families. There was considerable variability in the structure and composition of vegetation. Most species were present in particular sites and the composition of communities appears to be related to the heterogeneity of the habitat within the reserve. In areas of shallow or rocky soil, vegetation types present include Allocasuarina huegeliana woodland, Grevillea paradoxa low scrubland and Acacia neurophylla medium shrubland.In a seasonally wet area, vegetation types present include low open grassland; Eucalyptus capillosa (wandoo) woodland; and, Acacia saligna thicket. In deep, dry sandy soil, vegetation types include Phebalium tuberculosum shrubland, Acacia acuminata and Acacia coolgardiensis thickets. On relatively flat areas that gain water from adjacent large granite hills, the vegetation consists mainly of tall, open woodlands of Eucalyptus species. Vegetation types include: medium tall Eucalyptus salmonophloia woodland with Kunzea pulchella shrubland at the periphery of the Eucalyptus woodland. At rock areas, vegetation types present include dense Leptospermum erubescens thicket, low open Acacia prainii and Dodonaea viscosa shrubland. Of the Acacia populations studied, in A. lasiocalyx no recent seedling establishment was observed. It is hypothesised that recruitment occurs in particular periods. As the plants are associated with rock and soils are generally shallow, it appears that recruitment depends on run-off water from the rocks in winter. Continuous recruitment seems to be the pattern in A. prainii with both seedlings and saplings represented. A. fauntleroyi forms relatively small populations; apparently long drought periods (>l00 d) result in mass death and limit its population size. In A. hemiteles, no seedling stage was found, root competition (for water) from associated Eucalyptus species presumably limits its recruitment. Reproductive success of Acacia is affected by rainfall. A wet winter is required to induce flowering and further rain is required after flowering to promote pod development and good seed set.
All Acacia species suffer from drought in the reproduction season, however they differ in their degree of susceptibility. Leaflessness and tree shape also affect Acacia fecundity. Plants bearing more phyllodes produce more flowers and pods, and branches in the upper part of the crown bear heavier inflorescences. In 1998, all Acacia species at SRNR produced mature seed of low weight, with many immature and diseased seed, which gave poor germination. A late spring frost in 1998 is believed to be responsible for limited seed development. In two selected Acacia species, removal of phyllodes reduced the number of pods produced. Presumably, phyllode removal reduces photosynthate produced, therefore the competition among inflorescences (or pods) for resources is more intense and subsequent abortions are likely to occur. All Acacia species studied showed best germination in the cool winter temperature range. Apparently, seeds are adapted to germinate in winter when seasonal moisture is more likely to be available. The best temperature however, varied slightly between species. The grass species dominant in the reserve, except for Aristida contorta, also had more germination in cooler rather than warmer temperatures. The flora of SRNR is similar to typical vegetation of the Southwest. Generally, Acacia species are present only in particular sites, presumably were habitat moisture allows. Seedlings of Acacia species growing in naturally dry areas have greater root: shoot masses than those growing in seasonally wet areas. Biomass partitioning is an apparent strategy to conserve water. Of the 7 grass species, Amphipogon strictus appears to have fastest growth.
Eriachne ovata has greater root than shoot mass, while in all other species, shoot mass is greater than root mass; a characteristic of species that grow well in moist habitats. The longest shoots and roots are in Austrostipa elegantissima, an understorey species of eucalypt woodland. In A. fauntleroyi, the degree of hard-seededness varies between seed sizes. There is a higher proportion of soft seed in smaller seed. Seed of different sizes show some responses to different pre-treatments and incubation temperatures for germination. Larger seeds generally germinate in greater numbers after higher treatment temperatures. The best treatment for small seeds is pre-treatment at 75°C and incubated at 15°C. For medium and large seed, best pre-treatment is at 75°C with incubation at 30°C or soaking in boiling water and incubation at either 15 or 3°C. In A. prainii, seed size; pre-treatment; incubation; and, their interaction all affected germination; larger seeds are more viable. The best treatment to promote germination of A. prainii is soaking in boiling water and incubation at 25°C. In both A. fauntleroyi and A. prainii, larger seeds produce larger seedlings. Seedlings from large seeds have the potential for more rapid pre-photosynthetic growth. Larger, heavier seed has a thicker seed coat. The seed coat of A. prainii is thicker than in A. fauntleroyi; the difference in seed coat thickness is reflected by more soft seed in A. fauntleroyi (35%) than in A. prainii (6%).
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Hüttenmoser, Beate. "Staudenverwendung im Öffentlichen Grün." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1185550009906-62928.
Full textAbstract:
In vielen Städten wird zurzeit der Versuch unternommen, Staudenpflanzungen zur Steigerung der Qualität des Stadtbildes einzubringen. Die Pflanzungen sollen einem gewissen Qualitätsstandard genügen und gleichzeitig soll ihre Pflege möglichst geringe Kosten verursachen. In vorliegender Untersuchung wurden ästhetische und pflegerische Aspekte von Staudenpflanzun¬gen im Hinblick auf ihre Anwendung für das öffentliche Grün untersucht. Dabei ging es in erster Linie darum, das Verhältnis zwischen der ästhetischen Wirkung von Pflanzungen unterschiedlicher Artenzahl zum Pflegeaufwand zu ermitteln. Zusätzlich wurde der Einfluss eines zusätzlichen Rück-schnittes einzelner Arten im Sommer auf die genannten Faktoren untersucht. Um zu einem differenzierten Bild zu gelangen wurde außerdem eruiert, welche Rolle der Flächendeckungsgrad, die unerwünschte Beiflora sowie Krankheiten in diesem Kontext spielen.
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Proctor, Cynthia Lambert. "Effect of fertilizer nitrogen rate and time of application on growth and performance of six herbaceous perennials and soil solution nitrogen concentration in a simulated landscape." NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-01082006-144404/.
Full textAbstract:
Herbaceous perennials are planted worldwide in public gardens, and commercial and home landscapes. Little research based information exists on response of herbaceous perennials to fertilizer nitrogen (FN) rate and timing and the potential for loss of applied N via leaching. Therefore, we constructed simulated landscapes and installed canna lily (Canna L. 'President'), coreopsis (Coreopsis verticillata L. 'Moonbeam' ), purple coneflower (Echinacea purpurea L. 'Magnus'), iris (Iris siberica L. 'Caesar?s Brother'), switchgrass (Panicum virgatum L. 'Shenandoah'), sedum (Sedum L. 'Herbstfreude'), and sage (Salvia x sylvestris L. 'East Friesland') to determine how FN rate and timing affected growth and performance of herbaceous perennials and potential N leaching. Porous ceramic cup lysimeters were installed in situ in each landscape plot 38 cm below the soil surface to examine the effects of FN rate and timing on soil solution N concentrations. The experiment was a 4 x 4 factorial in a randomized complete block design with four replications. Four rates of FN: 0, 7, 14, and 28 g?m-2 N were divided equally into two applications and applied at the following times: 1) winter (Jan. 15 and Feb.15), 2) spring (Apr. 15 and May 15), 3) summer (June 15 and July 15), or 4) fall (Sept. 15 and Oct.15) beginning 2001. Soil solution samples were collected approximately every 2 weeks from Jan. 30, 2002 to Nov. 3, 2003 and analyzed to determine soil N (NO3- and NH4+) concentrations. Data collected in 2002 and 2003 for each species included the following number of flowers, plant visual evaluations, growth index (GI), and top dry weight. In 2003, mineral nutrient concentration was determined for each species. Plant response to treatments varied in 2002 and 2003. Our results indicated that despite statistical significance differences, many differences were small and FN treatments had little impact on the growth and ornamental qualities of these species. However, applying no N may not advisable, as some perennials species did benefit from an FN application during a specific time. Soil N concentrations remained above 10 mg?L-1 for 110 days, 62 days, 52 days, and 192 days when applied during January/February, April/May, June/July, 2002 and September/October in 2001 respectively. In 2003, soil N concentrations from FN rates of 7 g?m-2 N (1.5 lbs?1000 ft-2) and 14 g?m-2 N (3.0 lbs?1000 ft-2) applied in January/February, June/July, April/May and September/October remained below 10 mg?L-1 until the end of the study (Oct. 14, 2003). Nitrogen concentrations increased to 19 mg?L-1, 38 mg?L-1, and 21 mg?L-1, after 28 g?m-2 N (6.0 lbs?1000 ft-2) was applied in January/February, April/May, and June/July, respectively. To cover the needs of a wide variety of perennial species that usually exists in one landscape as well as minimize N concentrations in the soil solutions, we recommend a low to moderate rate of FN (5 g?m-2 to 15 g?m-2 ) be applied in split applications in spring and early fall.
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Hüttenmoser, Beate. "Staudenverwendung im Öffentlichen Grün: Untersuchung zur Problematik ästhetischer und pflegerischer Aspekte von Staudenpflanzungen für das Öffentliche Grün." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A23943.
Full textAbstract:
In vielen Städten wird zurzeit der Versuch unternommen, Staudenpflanzungen zur Steigerung der Qualität des Stadtbildes einzubringen. Die Pflanzungen sollen einem gewissen Qualitätsstandard genügen und gleichzeitig soll ihre Pflege möglichst geringe Kosten verursachen. In vorliegender Untersuchung wurden ästhetische und pflegerische Aspekte von Staudenpflanzun¬gen im Hinblick auf ihre Anwendung für das öffentliche Grün untersucht. Dabei ging es in erster Linie darum, das Verhältnis zwischen der ästhetischen Wirkung von Pflanzungen unterschiedlicher Artenzahl zum Pflegeaufwand zu ermitteln. Zusätzlich wurde der Einfluss eines zusätzlichen Rück-schnittes einzelner Arten im Sommer auf die genannten Faktoren untersucht. Um zu einem differenzierten Bild zu gelangen wurde außerdem eruiert, welche Rolle der Flächendeckungsgrad, die unerwünschte Beiflora sowie Krankheiten in diesem Kontext spielen.
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Ozdarici, Ok Asli. "A Segment-based Approach To Classify Agricultural Lands Using Multi-temporal Kompsat-2 And Envisat Asar Data." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614195/index.pdf.
Full textAbstract:
Agriculture has an important role in Turkeyhence automated approaches are crucial to maintain sustainability of agricultural activities. The objective of this research is to classify eight crop types cultivated in Karacabey Plain located in the north-west of Turkey using multi-temporal Kompsat-2 and Envisat ASAR satellite data. To fulfill this objective, first, the fused Kompsat-2 images were segmented separately to define homogenous agricultural patches. The segmentation results were evaluated using multiple goodness measures to find the optimum segments. Next, multispectral single-date Kompsat-2 images with the Envisat ASAR data were classified by MLC and SVMs algorithms. To combine the thematic information of the multi-temporal data set, probability maps were generated for each classification result and the accuracies of the thematic maps were then evaluated using segment-based manner. The results indicated that the segment-based approach based on the SVMs method using the multispectral Kompsat-2 and Envisat ASAR data provided the best classification accuracies. The combined thematic maps of June-August and June-July-August provided the highest overall accuracy and kappa value around 92% and 0.90, respectively, which was 4% better than the highest result computed with the MLC method. The produced thematic maps were also evaluated based on field-based manner and the analysis revealed that the classification performances are directly proportional to the size of the agricultural fields.
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Williamson, Michelle Leigh. "Differential responses of tillers to floral induction in perennial ryegrass (Lolium perenne L.) : implications for perenniality : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Biology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/842.
Full textAbstract:
Development of sustainable practices is an important goal in agriculture. One possibility involves the development of perennial cereal crops, but the mechanisms of perenniality first need to be understood. While in annual cereals flowering structures die following seed production, in perennial grasses, perenniality is achieved by maintaining at least one shoot in a vegetative state. There are two views on perennating tiller origin in perennial grasses: some authors suggest that all over-wintering tillers flower in spring and summer, leaving spring-initiated tillers to perennate, while others indicate that spring-initiated tillers are too immature to survive summer conditions, thereby implying that flowering must be prevented in some over-wintering tillers. An understanding of perenniality will therefore require an understanding of flowering control in these species. Temperate perennial grasses have dual induction requirements for flowering, where plants become competent to perceive inductive signals following vernalisation, and flowering is initiated by inductive photoperiods. Two hypotheses were formulated to test these models. The ‘environmental control hypothesis’ stated that all adequately vernalised perennial ryegrass tillers would flower on sufficient exposure to inductive photoperiods. Alternatively, the ‘spatial control hypothesis’ stated that in addition to the environmental mechanisms, a spatial control mechanism acts to regulate flowering. Two experiments were conducted to test these hypotheses. Perennial ryegrass and Italian (annual) ryegrass were induced to flower and differences between the annual and perennial habits at flowering time were observed. However neither hypothesis was proven. In the second experiment, flowering was studied in detail in individual tillers of perennial ryegrass. The eldest tiller flowered in all flowering plants. The second eldest tiller did not flower in 72% of plants with more than one reproductive tiller, while the third eldest tiller flowered in 94% of these plants. These data favour the spatial control hypothesis which suggests that a spatial regulatory mechanism might act to repress flowering in some competent perennial ryegrass tillers. These results were supported by studies of meristem morphology and by a preliminary gene expression study. Maintenance of older, established tillers in a vegetative state might allow the perennial plant a greater chance of survival during summer.
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Sencan, Secil. "Decision Tree Classification Of Multi-temporal Images For Field-based Crop Mapping." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605503/index.pdf.
Full textAbstract:
ABSTRACT
DECISION TREE CLASSIFICATION OF MULTI-TEMPORAL IMAGES FOR FIELD-BASED CROP MAPPING
Sencan, Seçil M. Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Assist. Prof. Dr. Mustafa Tü
rker August 2004, 125 pages A decision tree (DT) classification approach was used to identify summer (August) crop types in an agricultural area near Karacabey (Bursa), Turkey from multi-temporal images. For the analysis, Landsat 7 ETM+ images acquired in May, July, and August 2000 were used. In addition to the original bands, NDVI, PCA, and Tasselled Cap Transformation bands were also generated and included in the classification procedure. Initially, the images were classified on a per-pixel basis using the multi-temporal masking technique together with the DT approach. Then, the classified outputs were applied a field-based analysis and the class labels of the fields were directly entered into the Geographical Information System (GIS) database. The results were compared with the classified outputs of the three dates of imagery generated using a traditional maximum likelihood (ML) algorithm. It was observed that the proposed approach provided significantly higher overall accuracies for the May and August images, for which the number of classes were low. In May and July, the DT approach produced the classification accuracies of 91.10% and 66.15% while the ML classifier produced 84.38% and 63.55%, respectively. However, in August nearly the similar overall accuracies were obtained for the ML (70.82%) and DT (69.14%) approaches. It was also observed that the use of additional bands for the proposed technique improved the separability of the sugar beet, tomato, pea, pepper, and rice classes.
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Washburn, Jacob. "Trait Correlation and Confirmation of QTLs for Rhizome Growth and Over-wintering in Sorghum." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11410.
Full textAbstract:
A growing world population drives an ever-increasing need for food and energy. These challenges, along with depletion of water and fossil fuel resources, call for improvements in crop production systems and the cultivars used within them. Perennial cropping systems present an attractive solution to many of these problems. A greater understanding of the genetic control of over-wintering ability within crop species is one way to begin the process of making perennial cropping systems a possibility.
In this study an F3:F4 family derived from a cross between Sorghum bicolor (L.) Moench and S. propinquum (Kunth) Hitchc. segregating for rhizome production was phenotyped in both field and greenhouse environments for traits relating to rhizomatousness and over-wintering. Several statistical models were created to correlate rhizome growth and over-wintering. A known rhizome quantitative trait locus (QTL) region was saturated with SSR markers and the QTL interval was reduced from previous estimates of about 16 Mb or 7 cM to 12 Mb or 2 cM, a 25% or 71% reduction in physical or linkage distance respectively. Two previously unidentified QTL regions associated with over-wintering were also identified. Our results also support the hypothesis that rhizome growth is important and possibly necessary for over-wintering in Sorghum.
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Wang, Renhou [Verfasser]. "Flowering time control and perennialism in Arabis alpina, a perennial relative of Arabidopsis thaliana / vorgelegt von Renhou Wang." 2007. http://d-nb.info/989777383/34.
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Shenshyn, Oleg. "Dilema ukrajinského národního projektu: vytváření nových národních mýtů." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-341291.
Full textAbstract:
Ukrainian state lacks an effective historical memory policy. For this reason, the Ukrainian nation- building project lacks ideological capabilities to consolidate Ukrainian society. The dilemma regarding the national myths is the main challenge of the Ukrainian nation-building project. The dilemma emerged in choosing between the myth of the national liberation struggle of the Ukrainian Insurgent Army (UPA) and the myth of the Great Patriotic War. Both myths are struggling for an important place in the pantheon of Ukrainian history, but fisrt of all for a recognition of Ukrainian society. This resulted in the creation of conflicting historical identities. Ukrainian elite have long time speculated on the differences in the historical identity, which largely contributed to social fragmentation. This thesis describes how national myths interact with nation-building project and also analyzes the content of the most crucial interpretations of the historical myths.
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Oakley, Christopher G. Winn Alice A. "Inbreeding depression and mating system evolution in the perennial herb viola septemloba; and the evolutionary maintanence of cleistogamy." 2004. http://etd.lib.fsu.edu/theses/available/etd-11082004-160338.
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Thesis (M.S.)--Florida State University, 2004.Advisor: Dr. Alice A. Winn, Florida State University, College of Arts and Sciences, Dept. of Biological Science. Title and description from dissertation home page (viewed Jan. 18, 2005). Includes bibliographical references.
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Dubois, Jean-Jacques B. "Plant level response of seven herbaceous perennials to diurnal temperature cycling and sub-diurnal temperature variation." 2005. http://www.lib.ncsu.edu/theses/available/etd-01032005-152319/unrestricted/etd.pdf.
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Roberts, Christia M. "Research and development of herbaceous perennials as new potted plants for commercial floriculture : case studies with lewisia seed biology and dicentra postproduction performance." Thesis, 1995. http://hdl.handle.net/2429/4396.
Full textAbstract:
Commercial development of new flowering potted plants is stimulated by
overproduction of major crops worldwide and consumer demand for new products. The
process of product development was critically examined and the role of modern plant biology
research in the development process was investigated using new, non-commercial plant genera
for case studies in seed biology and postproduction longevity.
This examination included a review of the history of ornamental plant cultivation and
the scientific literature, and observation of projects in a major, international floriculture
production centre. Development work was most often undertaken by private, international
breeders and propagators of new crop cultivars. Some private producers conducted their own
breeding programs and successfully introduced new products. Product development
consultants and discipline-oriented scientists had a significant role in development work.
Crucial components of the process included identification of a plant species with potential in
floriculture, active involvement of flower producers, confidentiality and product promotion.
One case study investigated the mechanism of seed dormancy, and seed treatments
were tested to improve germination of Lewisia tweedyi and Lewisia cotyledon. These two
lewisia species were found to have dramatically different percent:; and rates of germination
under axenic conditions and in laboratory experiments. Decoating increased germination from
0 to 87% in L. tweedyi which suggests that the seed coat imposes dormancy in this species.
The role of the coat in seed dormancy was supported by measurements of seed coats in
transverse section under a scanning electron microscope. The L. t\v eedyi seed coat was found
to be 22% thicker than the L. cotyledon coat. Scarification of seeds with liquid nitrogen,
infusing gibberellic acid, and an 8 or 12-week stratification improved germination in both species.
Another case study determined the display life of potted plants of Dicentra eximia,
Dicentra formosa, and Dicentra spectabilis. More flowers opensd in a simulated interior
environment room if the plants were treated before harvest with an anionic silver thiosulfate
complex. This increase in flower number resulted in a 75% increase in the display life of D.
eximia (to 14 days) and a 65% increase in the display life of D. formosa (to 28 days). A
similar effect was achieved by producing the plants under supplemental irradiance which also
increased plant height and decreased production time. Height of D. spectabilis could be
controlled by the application of daminozide which had no effect on forcing time, flower
number or display life of the plants.
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Proctor, Cynthia Lambert. "Effect of fertilizer nitrogen rate and time of application on growth and performance of six herbaceous perennials and soil solution nitrogen concentration in a simulated landscape." 2005. http://www.lib.ncsu.edu/theses/available/etd-01082006-144404/unrestricted/etd.pdf.
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Ginke, Harold Charles. "A study of the role of potential competitors and the influence of a stubble oat mulch in the establishment of long-lived perennials in seeded prairie restorations." 1987. http://catalog.hathitrust.org/api/volumes/oclc/16508541.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1987.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 135-141).
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Graham, Gary Thomas. "New Perspectives on the Maintenance of Aqueous Ozone Residuals in Greenhouse and Nursery Irrigation Solutions." Thesis, 2012. http://hdl.handle.net/10214/3871.
Full textAbstract:
Ozonation has been utilized for water treatment for over 100 years. During that time, the range of applications has grown considerably, and includes the remediation of nursery and greenhouse irrigation water. Ozone is dissolved into irrigation water to kill pathogens and degrade chemical contaminants. By convention, growers remove ozone from solutions, prior to distribution to the crop, to avoid phytotoxic effects. The available literature regarding aqueous ozone (O3(aq)) phytotoxicity is limited, making this a sagacious practice, although the removal does preclude any ancillary benefits beyond the point of treatment.
The effects of applying O3(aq) under two irrigation systems are examined. Initial studies suggested O3(aq) concentrations as high as 20 mg⋅L-1 could be applied directly to mineral wool substrate in a limited (one time) fashion without a negative response. To be effective as a remediation tool, however, ozone would need to be applied more frequently (e.g. daily). The effects of daily O3(aq) application, via drip irrigation in mineral wool hydroponic tomato culture, was examined. In the first of two studies, daily applications of 3.0 mg⋅L-1 O3(aq) elicited an overall positive growth response. In a follow-up study, 6.0 mg L-1 elicited a negative response.
Nursery operators often utilize overhead irrigation. A study was conducted to determine if overhead irrigation utilizing O3(aq) was compatible with select woody perennial nursery species. The amount of ozone lost from solution during application was examined, as well as crop response to the ozone environment generated. It was shown that 60 to 70% of the ozone was unaccounted for at canopy level, while phytotoxic effects were elicited at emitter concentrations above 1.5 mg L-1.
Marchantia polymorpha is a significant weed species in greenhouse and nursery production; a species with few control options. Anatomical features of M. polymorpha suggested sensitivity to O3(aq). Studies were performed to examine contact time (CT) and exposure frequencies required for M. polymorpha suppression. A CT of 0.84 mg⋅L-1⋅min at an application frequency of 3-times/week achieved measurable suppression.Natural Science and Engineering Research Council (NSEARC); Ontario Ministry of Agriculture Food and Rural Affairs (OMAFRA); Ontario Centres of Excellence (OCE); Purification Research Technologies INC (PRTI); Flowers Canada (Ontario).