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1
Rowley, Marc A. „Orchard Floor Management“. DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1103.
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Orchard floor management is vital to tree health, yield, and fruit quality. Current standard management practices include maintaining a vegetation-free tree row and a grass-covered alleyway. This system is effective at limiting competition from undesirable vegetation and creating a favorable environment for the fruit trees. However, limitations to standard orchard floor practices are that the grass alleyway provides no nutrient benefit, and current practices do not readily lend themselves to organic management constraints. Alternative in-row and alleyway systems are requisite to creating improved orchard floor management systems. Three different approaches were used to investigate alternative orchard floor management strategies, including: alternative in-row weed control with combinations of mulch and organic herbicides, alternative alleyway management with legume cover crops, and combinations of in-row and alleyway alternative strategies. Although organic in-row weed control was best accomplished with combinations of straw and acetic acid, this management approach was not economically viable at current costs of labor and supplies, and current fruit prices. Alfalfa and alfalfa clover treatments contributed the most aboveground biomass and nitrogen among alternative alleyway covers, but consumed 45% more water than the conventional grass alleyway. In combinations of in-row and alleyway alternatives, birds-foot trefoil alleyway had a beneficial effect on tree growth compared to grass, while consuming the greatest amount of water. Peach yields were the highest for the integrated compost and NPK fertility treatments that used herbicides to minimize competition. Treatments that experienced the most competition from weeds, no herbicide and reduced herbicide treatments, resulted in lower yields. Weed fabric and tillage in-row weed control methods resulted in the highest tree growth as compared to the straw and alyssum treatments. Finally, results from the combined studies were integrated into a series of recommendations for commercial fruit growers. While alternatives to orchard floor management show a number of potential benefits for growers in the Intermountain West, additional work is needed to determine the long-term viability of these approaches.
2
Albertyn, Sonnica. „Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) population ecology in citrus orchards: the influence of orchard age“. Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/62615.
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Anecdotal reports in the South African citrus industry claim higher populations of false codling moth (FCM), Thaumatotibia (Cryptophlebia) leucotreta (Meyr) (Lepidoptera: Tortricidae), in orchards during the first three to five harvesting years of citrus planted in virgin soil, after which, FCM numbers seem to decrease and remain consistent. Various laboratory studies and field surveys were conducted to determine if, and why juvenile orchards (four to eight years old) experience higher FCM infestation than mature orchards (nine years and older). In laboratory trials, Washington Navel oranges and Nova Mandarins from juvenile trees were shown to be significantly more susceptible to FCM damage and significantly more attractive for oviposition in both choice and no-choice trials, than fruit from mature trees. Although fruit from juvenile Cambria Navel trees were significantly more attractive than mature orchards for oviposition, they were not more susceptible to FCM damage. In contrast, fruit from juvenile and mature Midnight Valencia orchards were equally attractive for oviposition, but fruit from juvenile trees were significantly more susceptible to FCM damage than fruit from mature trees. Artificial diets were augmented with powder from fruit from juvenile or mature Washington Navel orchards at 5%, 10%, 15% or 30%. Higher larval survival of 76%, 63%, 50% and 34%, respectively, was recorded on diets containing fruit powder from the juvenile trees than on diets containing fruit powder from the mature trees, at 69%, 57%, 44% and 27% larval survival, respectively. Bioassays were conducted to determine if differences in plant chemistry between fruit from juvenile and mature trees will have an impact on the susceptibility FCM to entomopathogenic nematodes (EPN), entomopathogenic fungi (EPF) and Cryptophlebia leucotreta granulovirus (CrleGV). No significant differences in the susceptibility of larvae reared on diets containing 15% fruit powder from juvenile and mature trees to EPN and EPF were recorded. Mortality of neonate larvae was significantly lower when placed on diets containing 15% fruit powder from mature trees (45% mortality) than diets containing 15% fruit powder from juvenile trees (61% mortality), after larvae ingested the lowest virus concentration tested, being 2 x104 OBs/ml. Data collected from field surveys showed significantly lower egg parasitism, virus infection of larvae and EPF occurrence in juvenile orchards than mature orchards. Egg parasitism was between 11% and 54% higher in mature orchards than juvenile orchards, with the exception of Mandarins during 2015, where egg parasitism was slightly higher in juvenile orchards, but not significantly so. A significantly higher proportion of larvae retrieved from mature orchards (7% of larvae) were infected with CrleGV than larvae retrieved from juvenile orchards (4% of larvae). A significantly higher occurrence of EPF was recorded in non-bearing and mature orchards, with 40% and 37% occurrence respectively, than in juvenile orchards, with 25% occurrence recorded. EPF occurrence in juvenile orchards increased significantly by 16% to 32% from the first to the third year of sampling. In contrast to results recorded in laboratory trials, similar or higher pest pressure in juvenile orchards than mature orchards did not always result in significantly higher levels of FCM damage under field conditions. FCM damage in juvenile orchards may have been lower than expected, as greater extremes of temperature and lower humidity were recorded in juvenile orchards, which would increase larval mortality. Results of this study showed that juvenile and mature orchards are significantly different and should be managed differently.
3
Middleton, Simon Guy. „Apple orchard light interception and productivity“. Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46448.
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4
Miranda, Ricardo Augusto Calheiros de. „Persistence of wetness in an apple orchard“. Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317993.
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5
Dennis, Amy Elizabeth. „'The Sleep Orchard' : poetry and critical commentary“. Thesis, Aberystwyth University, 2014. http://hdl.handle.net/2160/a2c4fafd-252c-4695-90d3-b2efc4e30cc4.
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The Sleep Orchard is a collection of poetry written in response to the life and artwork of Arshile Gorky. By mapping the differences as well as the deepening intersections between Gorky and the author, these poems highlight the complexities inherent in attempting to understand another’s life and art within the frame of one’s own consciousness. In addition to meditating on various paintings and the subsequent thoughts they inspire, the text shifts between reflection, recollection, description, confessionalism, and collage, ultimately carving an intimate trajectory through history, memory, vibrancy, and loss. The Invisible Foxglove Spine is a collection of ekphrastic poems in which personal and historical resonances often strive to transcend the purely visual realm of the paintings that initially inspired them. Notions of religion, gender, family, as well as avenues of human connectivity are addressed. The critical commentary explores notions of truth in biographical writing, the relation of this to my poetry collection The Sleep Orchard, as well as voice appropriation in connection with my manuscript on Arshile Gorky. Also investigated are notions of ekphrasis and gender in my shadow collection The Invisible Foxglove Spine, as well as the relationship between ekphrasis and the confessional as considered through the work of contemporary poets Pascal Petit and Deryn Rees-Jones.
6
Bortolotti, Gianmarco <1993>. „Evaluation of a 2D multileader training system for improving sustainability and precision orchard management applications in italian apple orchards“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10373/1/GB_PhD_Thesis_Uploaded.pdf.
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The presented study aimed to evaluate the productive and physiological behavior of a 2D multileader apple training systems in the Italian environment both investigating the possibility to increase yield and precision crop load management resolution. Another objective was to find valuable thinning thresholds guaranteeing high yields and matching fruit market requirements.
The thesis consists in three studies carried out in a Pink Lady®- Rosy Glow apple orchard trained as a planar multileader training system (double guyot). Fruiting leaders (uprights) dimension, crop load, fruit quality, flower and physiological (leaf gas exchanges and fruit growth rate) data were collected and analysed. The obtained results found that uprights present dependence among each other and as well as a mutual support during fruit development. However, individual upright fruit load and upright’s fruit load distribution on the tree (~ plant crop load) seems to define both upright independence from the other, and single upright crop load effects on the final fruit quality production. Correlations between fruit load and harvest fruit size were found and thanks to that valuable thinning thresholds, based on different vegetative parameters, were obtained. Moreover, it comes out that an upright’s fruit load random distribution presents a widening of those thinning thresholds, keeping un-altered fruit quality. For this reason, uprights resulted a partially physiologically-dependent plant unit. Therefore, if considered and managed as independent, then no major problems on final fruit quality and production occurred. This partly confirmed the possibility to shift crop load management to single upright. The finding of the presented studies together with the benefits coming from multileader planar training systems suggest a high potentiality of the 2D multileader training systems to increase apple production sustainability and profitability for Italian apple orchard, while easing the advent of automation in fruit production.
7
Zinzani, Michele. „Electric drives for ORTO - Orchard Rapid Transit Operation“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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This thesis is focused on a novel agricultural technique for orchard cultivations that allows to perform automatic and fossil fuel free cultivation operations. More specifically, the aim of this thesis work is to study and implement the electric traction system and control the vehicle that performs the automatic operations.
Starting from the analysis of each single component of the traction system, the control of the mobile platform will be then performed.
After a first control of the mobile platform in no load conditions, the implementation of the dynamic model will be performed in the Simulink environment. Different simulations representing typical operational missions will be performed to have a real idea concerning the behaviour of the traction system and the energy consumption of this solution.
Finally, the obtained results will be analysed for the future implementation of the mobile platform on the field.
8
Becker, Emily Jane. „Beyond Fruit: Examining Community in a Community Orchard“. PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2628.
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The Fruits of Diversity Community Orchard, located in Portland, Oregon in an affordable housing neighborhood, is a site of alternative food provisioning in which a group of people, organized by two nonprofits, work together to manage fruit and nut producing plants. Through conversations with volunteers who participate regularly and participant observation, this study explores the questions: What does community mean in the context of a community orchard? In what ways does partnering with a nonprofit from outside the neighborhood influence community and the way the project is operationalized?
This thesis situates community orchards within the literature on alternative food networks (AFN) and highlights three key findings drawing on literature about community development and race in AFNs. First, neighbors and non-neighbors who participate in the project propose different definitions of community. Second, neighbor involvement is limited by a number of factors, including neighborhood divisions and organizational challenges. Notably, orchard participants do not reflect the racial and ethnic diversity of the neighborhood, putting this project at risk of creating a white space in a majority people of color neighborhood and reproducing inequality rather than fighting against it. Finally, this research complicates the notion of community in alternative food networks and demonstrates how collaborating with an organization from outside the neighborhood impacted the community through increasing non-neighbor participation and through their communications, aesthetics, decision making, and inattention to racial dynamics in the neighborhood and orchard.
9
Robbie, Francis Anne. „Studies into factors affecting fruit production in young apple trees“. Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329559.
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10
Culumber, Catherine Mae. „Soil Nutrient Cycling and Water Use in Response to Orchard Floor Management in Stone-Fruit Orchards in the Intermountain West“. DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/5030.
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Fruit growers in Utah and other areas across the Intermountain West are faced with growing production challenges stemming from declining soil quality and water resources. Population growth presents challenges in terms of the cost and availability of land, but also presents opportunities in the form of new marketing options such as organic fruit. Few certified organic fruit orchards are operating in Utah currently, which is attributed to a lack of locally tested and adapted organic management practices. An organic peach orchard trial evaluated the effectiveness of different organic management approaches to enhance soil quality and conserve water without compromise to fruit tree growth and fertility. Two tree-row treatments: ‘straw mulch' (Triticum aestivum L.) and ‘living mulch’ (Lobularia maritima (L.) Desv.) were tested in combination with two alleyway groundcovers: ‘grass’ (Festuca rubra L. with Lolium perenne L.) and a legume, ‘Birdsfoot trefoil’ (Lotus corniculatus L.). The novel systems were compared with industry standards, tillage and weed fabric tree-rows with grass alleyways. Trefoil alleyway biomass deposited into tree-rows contributed an estimated 6.24 kg biomass and 0.21 kg total N/tree annually. Trefoil treatments had higher levels of organic carbon (C) and nitrogen (N), inorganic N, microbial biomass and enzyme activities, suggesting trefoil alleyways enhanced soil nutrient cycling, as well as C and N reserves in comparison to grass and tillage treatments. A functional gene array analysis was conducted to describe the mechanisms, microbial functional composition and diversity underlying the observed soil processes, however few differences were detected in soil community structure between soils under different orchard floor management.
Significantly lower leaf δ15N in trees grown with trefoil compared to grass, and an association between root biomass, diameter and trunk cross-sectional area (TCSA) suggests nitrogen sources derived from the trefoil groundcover contributed to improved fruit tree vigor. Few differences resulted among orchard treatments for water use (mm/week). Trends indicated slightly higher water use in trefoil over grass, but not enough to offset observed soil quality and tree growth benefits. These findings suggest, trefoil alleyways may provide ecological benefits such as improved soil quality and efficient nutrient cycling, without substantial increases in water use.
11
Holtz, Daniel. „Evaluation and design of a 20-acre avocado orchard“. Click here to view, 2010. http://digitalcommons.calpoly.edu/braesp/2/.
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Thesis (B.S.)--California Polytechnic State University, 2010.Project advisor: Charles Burt. Title from PDF title page; viewed on Apr. 19, 2010. Includes bibliographical references. Also available on microfiche.
12
Kang, Kyu-Suk. „Genetic gain and gene diversity of seed orchard crops /“. Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6071-9.pdf.
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13
White, John Gordon. „Control of rodent damage in Australian macadamia orchard systems“. Thesis, Queensland University of Technology, 1999.
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14
MIA, MD JEBU. „Alternative orchard floor management practices in the tree row“. Doctoral thesis, Università Politecnica delle Marche, 2021. http://hdl.handle.net/11566/290842.
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La gestione del suolo nel sottofila del frutteto dipende in gran parte dall’uso di erbicidi chimici e dalle lavorazioni e questo concorre al declino della biodiversità e della qualità del suolo, e infine risulta dannosa per la sostenibilità della coltivazione. Tuttavia, il declino del suolo può essere contrastato praticando strategie alternative più sostenibili, singole o integrate. La gestione dovrebbe mantenere il suolo coperto nel filare degli alberi con specie viventi spontanee o selezionate per il loro ruolo vitale nei servizi dell'agroecosistema e nel miglioramento della biodiversità nel frutteto.
Nel primo studio, due approcci meccanici integrati, la falciatura integrata (falciatrice e spazzola o disco) e la lavorazione integrata (sarchiatrice a lame e falciatura integrata), sono stati confrontati con il sistema gestito con erbicida standard in due frutteti commerciali di melo e pesco nelle Marche (Italia). Sono state misurate biodiversità del frutteto (copertura del suolo, numero di specie e produzione di biomassa), qualità del suolo (materia organica e contenuto di azoto), crescita degli alberi, resa e qualità dei frutti. Nel complesso, entrambe le pratiche integrate hanno dimostrato rispettivamente circa l'82%, il 91% e il 113% in più di diversità di specie, copertura del suolo e produzione di biomassa infestante rispetto al sistema gestito con erbicida. La falciatura integrata ha avuto effetti non significativi sulla sostanza organica del suolo e sulla disponibilità di azoto; tuttavia, è stato notato un miglioramento dell’equilibrio nel contenuto di azoto del suolo con riduzione del rischio della lisciviazione dei nitrati. Non è stato riscontrato alcun effetto negativo sulla crescita e sulla fisiologia degli alberi né sulla resa e sulla qualità dei frutti. I costi medi associati al controllo chimico delle infestanti sono stati rispettivamente del 66,5% e del 72% inferiori rispetto alla lavorazione integrata e alla falciatura integrata. Tuttavia, i sussidi forniti ai frutticoltori per incoraggiare pratiche di gestione sostenibile sono stati in grado di compensare tali costi aggiuntivi.
Nello studio finale della tesi, sono state realizzate pacciamature viventi con due specie selezionate: Alchemilla vulgaris e Mentha piperita a confronto con la vegetaziona naturale sfalciata regolarmente (controllo) in un meleto biologico sperimentale a Skierniewice, in Polonia. Entrambi le pacciamature viventi selezionate hanno soppresso le erbe infestanti e migliorato la biodiversità del frutteto producendo il 42,5% in più di biomassa secca con il 29% in più di specie (numero) e il 33% in più di copertura del suolo, rispetto agli appezzamenti falciati. La clorofilla e il contenuto di nutrienti nelle foglie di melo sono risultati più elevati negli appezzamenti con pacciamatura viva selezionata rispetto al controllo. Inoltre, hanno prodotto una densità del peso secco delle radici di melo (RDWD) superiore del 30-46%, mentre altri tratti morfologici delle radici come la lunghezza della radice (RL), l'area della superficie della radice (RSA), il diametro della radice (RD) e il volume della radice (RV) non sono stati modificati in modo significativo. Questi risultati suggeriscono che le specie utilizzate per la pacciamatura vivente possono migliorare notevolmente la biodiversità del frutteto senza compromettere la produttività degli alberi e l'attività delle radici.Orchard floor management in the tree row largely depends on chemical herbicides and soil tillage, and resulted in declining orchard biodiversity, soil quality, and proved to be detrimental to orchard sustainability. However, it can be restored by practicing more sustainable alternatives strategy either single or integrated. The practice should support covered soil with either spontaneous or selected living species in the tree row, as they can play a vital role in agroecosystem services and biodiversity improvement in the fruit orchard. In the first study, two integrated mechanical approaches; integrated mowing (mower and brush or disc) and integrated tillage (blade weeder and integrated mowing), were compared with the standard herbicide system in two commercial apple and peach orchards in Marche region (Italy). Orchard biodiversity (soil coverage, species number and biomass production), soil quality (organic matter and nitrogen content), tree growth, fruit yield and quality were measured. Overall, both integrated practices demonstrated approximately 82%, 91% and 113% more species diversity, soil coverage, and weed biomass production, respectively, than the herbicide systems. Integrated mowing had a non-significant effect on soil organic matter and N availability; however, an improvement was noticed while maintained a balance in soil N status by reducing nitrate leaching. No negative effect was found on tree growth, tree physiological constituents, fruit yield, and quality. The average costs associated with chemical weed control were 66.5% and 72% lower, respectively, compared to integrated tillage and integrated mowing. However, the government subsidies provided to the orchardists to encourage sustainable management practices were able to offset such additional costs. In the final study of the thesis, two selected living mulching species: Alchemilla vulgaris and Mentha piperita were compared with a mixture of natural vegetations with mowing (control) in an experimental organic apple orchard in Skierniewice, Poland. Both selected living mulches suppress weeds and enhance orchard biodiversity by producing 42.5% more dry biomass, 29% more species number, and 33% more soil coverage, compared to mowed plots. Apple leaf chlorophyll index and nutrient content were higher in selected living mulches plots than in control. In addition, they produced 30–46% higher apple root dry weight density (RDWD), while other root morphological traits such as root length (RL), root surface area (RSA), root diameter (RD), and root volume (RV) did not differ. These results suggest that the selected living mulching species can improve orchard biodiversity remarkably without impairing tree physiological constituents and root activity.
15
Zanotelli, Damiano <1982>. „Carbon fluxes and allocation pattern in an apple orchard“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4889/1/tesi_PhD_completed_DZ_ok2.pdf.
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Carbon fluxes and allocation pattern, and their relationship with the main environmental and physiological parameters, were studied in an apple orchard for one year (2010). I combined three widely used methods: eddy covariance, soil respiration and biometric measurements, and I applied a measurement protocol allowing a cross-check between C fluxes estimated using different methods. I attributed NPP components to standing biomass increment, detritus cycle and lateral export. The influence of environmental and physiological parameters on NEE, GPP and Reco was analyzed with a multiple regression model approach.
I found that both NEP and GPP of the apple orchard were of similar magnitude to those of forests growing in similar climate conditions, while large differences occurred in the allocation pattern and in the fate of produced biomass. Apple production accounted for 49% of annual NPP, organic material (leaves, fine root litter, pruned wood and early fruit drop) contributing to detritus cycle was 46%, and only 5% went to standing biomass increment. The carbon use efficiency (CUE), with an annual average of 0.68 ± 0.10, was higher than the previously suggested constant values of 0.47-0.50. Light and leaf area index had the strongest influence on both NEE and GPP. On a diurnal basis, NEE and GPP reached their peak approximately at noon, while they appeared to be limited by high values of VPD and air temperature in the afternoon. The proposed models can be used to explain and simulate current relations between carbon fluxes and environmental parameters at daily and yearly time scale. On average, the annual NEP balanced the carbon annually exported with the harvested apples. These data support the hypothesis of a minimal or null impact of the apple orchard ecosystem on net C emission to the atmosphere.
16
Zanotelli, Damiano <1982>. „Carbon fluxes and allocation pattern in an apple orchard“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4889/.
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Carbon fluxes and allocation pattern, and their relationship with the main environmental and physiological parameters, were studied in an apple orchard for one year (2010). I combined three widely used methods: eddy covariance, soil respiration and biometric measurements, and I applied a measurement protocol allowing a cross-check between C fluxes estimated using different methods. I attributed NPP components to standing biomass increment, detritus cycle and lateral export. The influence of environmental and physiological parameters on NEE, GPP and Reco was analyzed with a multiple regression model approach.
I found that both NEP and GPP of the apple orchard were of similar magnitude to those of forests growing in similar climate conditions, while large differences occurred in the allocation pattern and in the fate of produced biomass. Apple production accounted for 49% of annual NPP, organic material (leaves, fine root litter, pruned wood and early fruit drop) contributing to detritus cycle was 46%, and only 5% went to standing biomass increment. The carbon use efficiency (CUE), with an annual average of 0.68 ± 0.10, was higher than the previously suggested constant values of 0.47-0.50. Light and leaf area index had the strongest influence on both NEE and GPP. On a diurnal basis, NEE and GPP reached their peak approximately at noon, while they appeared to be limited by high values of VPD and air temperature in the afternoon. The proposed models can be used to explain and simulate current relations between carbon fluxes and environmental parameters at daily and yearly time scale. On average, the annual NEP balanced the carbon annually exported with the harvested apples. These data support the hypothesis of a minimal or null impact of the apple orchard ecosystem on net C emission to the atmosphere.
17
Shateryan, Djavad. „Evaluation of three cycles of recurrent phenotypic selection for forage yield in orchardgrass and timothy“. Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26140.
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Three cycles of recurrent restricted phenotypic selection (RRPS) were carried out on two cultivars each of timothy (Phleum pratense L.) and orchardgrass (Dactylis glomerata L.). The selections were conducted at the E. A. Lods Agronomy Research Center of Macdonald Campus of McGill University from 1984 to 1988. Individual plant selections were based on dry matter yields of 25 plants. Within each of 16 grids, the five highest yielding genotypes were selected (i.e. 80 genotypes overall) and allowed to interpollinate. Equal weights of seeds from each of the 80 selected plants were mixed in each cycle. Evaluation trials were carried out in both sward and spaced stand from 1989 to 1993 to assess the effectiveness of selection in improving dry matter yield. Several other morphological and physiological characteristics of cycles were recorded to find possible associated changes.Three cycles of RRPS were not effective in increasing forage dry matter yields. The lack of response may be due to a narrow genetic base in the source populations and/or the population size under selection may have been too small, resulting in inbreeding depression. Another explanation for the ineffective selection may be non-random pollination among selected plants. The selection for forage yield produced some minor changes in other characteristics. There was a tendency towards increased plant height and circumference in orchardgrass; however, for timothy, height and circumference were reduced by selection. Cycle 3 of Avon orchardgrass was one day later in maturity and there was also a tendency for later maturity for timothy.
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Lai, Ben Shu Kwan. „Pollination dynamic in an advanced generation Douglas-fir seed orchard“. Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/7717.
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The objective of seed orchard management is to maximize the genetic gain while maintaining
sufficient level of genetic diversity in the orchard’s crops; however, balancing these two
parameters is a challenging task. Eight polymorphic nuclear microsatellite DNA markers were
used to construct the full pedigree of 801 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)
bulk seeds from 49 orchard parents and 4 external supplemental mass pollination (SMP) donors.
Parental balance curves indicated that 80% of the gametes were produced by 23, 45 and 37% of
females, males and clones, respectively. Contamination was found to be 10.36% with overhead
cooling applied. Selfing rate was found as 15.23% due to the over representation of few orchard
clones. The aggregate SMP (internal & external) success rate was estimated to be 15.02%. The
female, male and clonal effective population size (Ne) was estimated to be 6.49, 26.00 and 13.70,
respectively. The reduction of Ne is mainly the result of unequal parental contribution and to a
minor extent by the co-ancestory of the orchard’s parents. The seed crop’s genetic worth was
estimated to be 10.23 and -1.07 for volume and wood density, respectively. High correlations
between visual reproductive assessment methods F2 (r = 0.90 P < 0.01) and M3 (r 0.77, P <
0.05) with DNA analysis give credence to the visualize assessment methods. The result of this
study indicated that the seed orchard deviated from the ideal conditions affecting the expected
genetic diversity and gain estimates.
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Fredriksson, Emelie. „Tent isolation experiment in an advanced Scots pine seed orchard“. Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-76290.
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Pollen contamination is a severe problem in production breeding programs since it reduces the expected gain. In an attempt to solve this problem Skogforsk created an isolation experiment in the advanced Scots pine (Pinus sylvestris) seed orchard Västerhus in Västerbotten, Sweden. This experiment involves covering blocks of trees with a tent during the pollination period so that they only can mate with each other inside. To evaluate the effects of this tent treatment one tree from inside a tent with supplementary mass pollination (SMP) and one tree from the open control were chosen for this study. 48 seeds from each tree were sampled and genotypes at 9 microsatellite (SSR) loci. The likelihood and exclusion methods for paternity assignment were used to establish the fathers to these seeds. The results showed 0% contamination inside the tent and 4-8% outside in the control. The number of fathers contributed to the fertilization of the 48 seeds was 9 inside and 15 outside. The selfing rate was unexpectedly high, 10% inside the tent and 19% outside. The mating system inside the tent need to be further evaluated to fully understand what other effect the treatment has on the future progeny.
20
Bresilla, Kushtrim <1988>. „Sensors, Robotics and Artificial Intelligence in Precision Orchard Management (POM)“. Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/8980/1/BRESILLA_DISSERTATION.pdf.
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Image/video processing for fruit detection in the tree using hard-coded feature extraction algorithms has shown high accuracy on fruit detection during recent years. While accurate, these approaches even with high-end hardware are still computationally intensive and too slow for real-time systems. This paper details the use of deep convolution neural networks architecture based on single-stage detectors. Using deep-learning techniques eliminates the need for hard-code specific features for specific fruit shapes, color and/or other attributes. This architecture takes the input image and divides into AxA grid, where A is a configurable hyper-parameter that defines the fineness of the grid. To each grid cell an image detection and localization algorithm is applied. Each of those cells is responsible to predict bounding boxes and confidence score for fruit (apple and pear in the case of this study) detected in that cell. We want this confidence score to be high if a fruit exists in a cell, otherwise to be zero, if no fruit is in the cell. More than 100 images of apple and pear trees were taken. Each tree image with approximately 50 fruits, that at the end resulted on more than 5000 images of apple and pear fruits each. Labeling images for training consisted on manually specifying the bounding boxes for fruits, where (x, y) are the center coordinates of the box and (w, h) are width and height. This architecture showed an accuracy of more than 90\% fruit detection. Based on correlation between number of visible fruits, detected fruits on one frame and the real number of fruits on one tree, a model was created to accommodate this error rate. Processing speed is higher than 20FPS which is fast enough for any grasping/harvesting robotic arm or other real-time applications.
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Langrell, Stephen Richard Henry. „Molecular phylogeny, detection and epidemiology of Nectria canker (Nectria Galligena Bres.)“. Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/8140.
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Kess, Joseph Anthony. „Reproductive dynamics and fingerprinting effort in a Douglas-fir seed orchard“. Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43421.
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Seed orchards are the tree improvement programs’ production populations used to predictably package genetic gain and diversity achieved during the breeding cycle. Genetic gain and diversity delivered by seed orchards is calculated under the assumption of reproductive randomness, equality, and synchrony. These ideal expectations are not fulfilled by any existent seed orchards and deviations in gametic contribution by orchard parents’ makes genetic gain and diversity unpredictable. In this study, five Douglas-fir (Pseudotsuga menziesii) microsatellite markers (Slavov et al 2004) were used to genotype 66 orchard parents, 14 of which were also supplemental mass pollination (SMP) pollen donors, and 396 bulk seeds from the 2009 seed crop of a wind-pollinated Douglas-fir seed orchard. Genotype data were analyzed using the likelihood based CERVUS parentage analysis program (Kalinowski et al 2007) for full pedigree reconstruction. In this orchard, 14% of paternal gametic contributions came from outside males. Parental balance curves showed that 80% of paternal, maternal, and gametic contributions were made by 38 (58%), 34 (52%) and 37 (56%) orchard parents, indicating that the greatest gametic contribution inequality was attributable to maternal gametic contribution. Differences in gametic contribution and common ancestry between orchard parents decreased the effective number of males, females, and population size to 42, 37, and 41, lower than the census number of 66 parents. Selfing was 24.24%, higher than that reported for many Douglas-fir seed orchards. High selfing may be attributed to reproductive asynchrony or differences in parental reproductive output. Supplemental mass pollination did not result in significantly higher paternal gametic contribution. Failure of SMP may be attributed to either incorrect timing of application or competition with ambient pollen. The minimum number of genotyped seeds required for accurate contamination estimate was 150, identified by jackknife sampling of the total genotyped seed sample.
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Neilsen, Denise. „Characterization and plant availability of zinc in British Columbia orchard soils“. Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72835.
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Lack, K. J. „British orchard Drosophila species and the transmission of apple brown rot“. Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355736.
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Cant, Ross James. „Air jet behaviour in porous structures with application to orchard spraying“. Thesis, University of Surrey, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298821.
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Samuel, Örn. „Estimating Light Interception of Orchard Trees Using LiDAR and Solar Models“. Thesis, Linköpings universitet, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-134125.
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In farming of fruit trees it is of interest to know the light interception of the trees. Therefore, in this project, a geometric model of the trees was derived using LiDAR data and this was combined with a sky model to estimate the light interceptionof orchard trees. The light interception was estimated by first synthesising a discrete model of the hemispherical sky, which holds a measure of global lightradiation in each node. The light interception of the trees was then estimated by ray tracing from the sky, applying a radiation absorption model where rays passed the point cloud representation of the trees. Comparing the interception model to measurements of photosynthetically active radiation (PAR) underneath a tree, the qualitative agreement was high and the quantitative analysis showed a reasonable, albeit noisy, correspondence between the model output and the real world measurements. When comparing the estimations produced by the solar-geometry model and the tree volume (estimated also with LiDAR), a correspondence between the surface area of the tree and the interception was found. When comparing tree volume and light interception against actual yield numbers (total weight, average fruit weight and fruit count per tree), the observable trend was that light interception did better in predicting the average fruit size, while the volume did a better job of estimating the two others. The results were encouraging, however, because ground truth data were only available for 18 trees, future work will have to compare with a greater number of measurements over multiple growing seasons.
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Kisekka, Isaya. „Evapotranspiration based irrigation scheduling for a tropical fruit orchard in south Florida“. [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0025090.
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McCloskey, William B., Glenn C. Wright und Kathryn C. Taylor. „Managing Vegetation on the Orchard Floor in Flood Irrigated Arizona Citrus Groves“. College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/220517.
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Several orchard floor management strategies were evaluated beginning in the fall of 1993 in experiments on the Yuma Mesa in a Limoneira 8A Lisbon lemon grove and in a Valencia orange grove at the University of Arizona Citrus Agricultural Center (CAC) in Waddell, Arizona. On the Yuma Mesa, disking provided satisfactory weed control except underneath the tree canopies where bermudagrass, purple nutsedge, and other weed species survived. Mowing the orchard floor suppressed broadleaf weed species allowing the spread of grasses, primarily bermudagrass. Preemergence (Solicam and Surflan) and postemergence (Roundup and Torpedo) herbicides were used to control weeds in the clean culture treatment in Yuma. After two harvest seasons (1994-95 and 1995-96), the clean culture treatment resulted in greater yield than the other treatments. At the CAC, clean culture (in this location no preemergence herbicides were used), mowed resident weeds, and Salina strawberry clover orchard floor management schemes were compared. Again the clean culture treatment yielded more than the mowed resident weeds. The yield of the strawberry clover treatment was somewhat less than the clean culture yield but not significantly less. The presence of cover crops or weeds on the orchard floor were found to modulate tree canopy temperatures, and to have beneficial effects on soil nitrogen and soil organic matter content, but no effect on citrus leaf nutrient content. The decrease in yield in the mowed resident weed treatments compared to the clean culture treatment in both locations was attributed to competition for water.
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McCloskey, William B., Glenn C. Wright und Kathryn C. Taylor. „Managing Vegetation on the Orchard Floor in Flood Irrigated Arizona Citrus Groves“. College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/220523.
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Several orchard floor management strategies were evaluated beginning in the fall of 1993 in experiments on the Yuma Mesa in a 'Limoneira 8A Lisbon' lemon grove and in a 'Valencia' orange grove at the University of Arizona Citrus Agricultural Center (CAC) in Waddell, Arizona. On the Yuma Mesa, disking provided satisfactory weed control except underneath the tree canopies where bermudagrass, purple nutsedge, and other weed species survived. Mowing the orchard floor suppressed broadleaf weed species allowing the spread of grasses, primarily bermudagrass. Pre-emergence (Solicam and Surffan) and post-emergence (Roundup and Torpedo) herbicides were used to control weeds in the clean culture treatment in Yuma. After three harvest seasons (1994-95 through 1996-97), the clean culture treatment resulted in greater yield than the other treatments. At the CAC, clean culture (in this location no pre -emergence herbicides were used,) mowed resident weeds, and Salina strawberry clover orchard floor management schemes were compared. Again the clean culture treatment yielded more than the mowed resident weeds. The yield of the strawberry clover treatment was somewhat less than the clean culture yield but not significantly less. The presence of cover crops or weeds on the orchard floor were found to have beneficial effects on soil nitrogen and soil organic matter content, but no effect on citrus leaf nutrient content. The decrease in yield in the mowed resident weed treatments compared to the clean culture treatment in both locations was attributed to competition for water.
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Rabie, Louise. „An evaluation of the specific apple replant problem in Western Cape orchard soils“. Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52108.
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Thesis (MScAgric)--University of Stellenbosch, 2001.ENGLISH ABSTRACT: Apple replant disease (ARD) is one of the major impediments to the establishment of an economically viable apple orchard on sites previously planted to apple. In spite of extensive research on ARD, the etiology remains to be fully elucidated. A possible biological origin of ARD etiology in South Africa was investigated by the dilution of replant field soil with sterilised soil. Commercial orchards with ARD were selected for use in pot trials and disease severity evaluated after three months, by measuring shoot length, dry mass of plants as well as root discolouration. Although diluting replant soil to 25 and 50% (v/v) significantly reduced the effects of ARD, symptoms were only absent in 0% replant soil. It was clear that seedlings planted in any mixture containing replant soil, even only 25% replant soil, consistently exhibited symptoms of stunted growth and root discolouration similar to those seedlings grown in 100% replant soil. This indicates that ARD in South Africa is primarily of a biological nature. As an initial step in formulating sustainable disease control alternatives to replace methyl bromide, pot trials were conducted to assess the impact of compost treatments as well as biological control products on ARD. Compost as well as sterilised and unsterilised compost teas (compost extract) significantly increased seedling growth even under optimum nutrient conditions when compared to the control, suggesting that they negate the effects of ARD. Results also indicated that applying high concentrations of compost does not necessarily provide additional growth benefits compared to lower concentrations. Results with biocontrol formulations were less favourable. Only one of the biocontrol formulations, a combination of Bacillus spp. (Biostart®) improved growth significantly compared to the control. There was, however, some inconsistency with results for the different trials conducted using this product. Fungal as well as nematode populations associated with ARD soils were characterised to the generic level to get a clearer understanding of the etiology of ARD in South Africa. Pythium and Cylindrocarpon spp. were consistently isolated from all six replant soils in all trials that formed part of this study, indicating that these fungi may have a role in ARD etiology in South Africa. Nematodes implicated in ARD development were inconsistently associated with ARD soils used in these studies. This suggests that nematodes do not have a primary causal role in ARD etiology in South Africa. Field trials were conducted in commercial orchards to assess the impact of organic amendments and promising biological control products, as indicated by the pot trials, on ARO severity under field conditions. These biological soil amendments were also compared with the standard chemical control methods for ARO, methyl bromide and chloropicrin. In all three trials established, compost and mulch as well as manure and mulch, consistently increased growth to the same extent as the standard chemical treatments and by combining these chemical treatments with organic amendments a significant, additional growth increase could be attained. Biocontrol formulations evaluated in field studies gave variable results. Biostart® improved growth when applied on its own, but not in combination with the chemical Herbifume (metham-sodium). Inoculating soil with effective microorganisms (EM), consisting primarily of photosynthetic bacteria, had no significant effect on growth. Results from this study indicate that application of organic amendments could possibly substitute for soil fumigation in replanted apple orchards. However, compost quality standards need to be implemented and because few types of compost are universally effective, different types of composts should be compared in specific soil environments before recommendations can be made. Oue to variable results with biocontrol products, ARO management with these biological soil amendments cannot be guaranteed at this stage and further studies are recommended.
AFRIKAANSE OPSOMMING: EVALUERING VAN DIE SPESIFIEKE APPELHERVESTIGING-PROBLEEM IN BOORDE IN DIE WES-KAAP Appelhervestiging-siekte (AHS) skep 'n groot probleem in die vestiging van jong appelbome op grond waar daar reeds voorheen appels verbou is. Ten spyte van omvangryke navorsing is die oorsaak van die probleem nog hoofsaaklik onbekend. 'n Moontlike biologiese oorsaakleer is in Suid-Afrika ondersoek deur die hervestigings-effek te probeer verminder deur die vermenging van hervestigingsgrond met gesteriliseerde grond. Kommersiële boorde met 'n appelhervestigingsprobleem is geselekteer en gebruik in potproewe. Die ernstigheidsgraad van die siekte is na drie maande se groei geevalueer deur lootlengte, droë massa en wortelverkleuring te meet. Alhoewel verdunning van die hervestigingsgrond tot 50 en 25% (vlv) die effek van AHS op groei betekenisvol verminder het, kon die skadelike effek van die veroorsakende faktor slegs uitgeskakel word deur saailinge in 100% gesteriliseerde grond te plant. Dit was duidelik dat saailinge wat in enige grondmengsel geplant is waarin hervestigingsgrond voorgekom het, selfs al was dit net 25%, konsekwent simptome van vertraagde groei en wortelverkleuring getoon het. Dit is 'n aanduiding dat AHS in Suid-Afrika hoofsaaklik biologies van aard is. Potproewe is uitgevoer as 'n eerste stap in die formulering van volhoubare siektebeheer-strategieë, om die impak van kompos-behandelings en biologiese beheer produkte op AHS te ondersoek. Kompos sowel as gesteriliseerde en ongesteriliseerde kompos-tee (kompos-water) het, selfs onder optimale voedingsomstandighede, die groei van saailinge betekenisvol verbeter. Dit dui aan dat hierdie behandelings die effek van AHS kan teenwerk. Resultate het ook daarop gedui dat hoër kompos konsentrasies nie noodwendig enige addisionele voordele vir groei inhou in vergelyking met laer konsentrasies nie. Resultate met biologiese beheer produkte was minder gunstig. Slegs een van die produkte wat geëvalueer is, 'n kombinasie van Bacillus spp. (Biostart®), het groei betekenisvol verbeter in vergelyking met die kontrole. Resultate was egter inkonsekwent vir die verskillende proewe waarin hierdie produk gebruik is. Swampopulasies sowel as aalwurmpopulasies wat met hervestigingsgrond geassosieer word, is geïdentifiseer tot op generiese vlak om vas te stel waardeur AHS in Suid-Afrika veroorsaak word. Pythium en Cylindrocarpon spp. is konsekwent van al ses hervestigingsgronde geïsoleer wat daarop dui dat hierdie twee swamgenera 'n beduidende rol in AHS ontwikkeling in Suid-Afrika mag hê. Aalwurms wat aangedui is in die literatuur om 'n moontlike rol in AHS te hê, was slegs in enkele gevalle geassosieer met hervestigingsgronde waarvan in hierdie studie gebruik gemaak is. Die gevolg-trekking is dus gemaak dat aalwurms nie 'n betekenisvolle rol speel as hoof-veroorsakende organisme onder Suid-Afrikaanse toestande nie. Veldproewe is uitgevoer in kommersiële appelboorde om vas te stel wat die effek van organiese materiaal, asook belowende biologiese beheermiddels, soos aangedui deur potproewe, op AHS onder veldtoestande is. Die biologiese grondtoedienings is ook vergelyk met die standaard chemiese beheermiddels (metielbromied en chloorpikrien). In al drie proewe wat gevestig is, het kompos met 'n deklaag, sowel as kraalmis met 'n deklaag, groei betekenisvol verbeter tot dieselfde mate as chemiese middels. Daar kon ook 'n beduidende, addisionele groeitoename gemeet word in gevalle waar chemiese middels met organiese materiaal gekombineer is. Resultate met biologiese beheer formulasies wat onder veldtoestande geëvalueer is, het gevarieer. Biostart® het groei verbeter wanneer dit alleen toegedien is, maar in kombinasie met die chemiese middel Herbifume (metham-sodium) het dit geen effek gehad nie. Die inokulering van grond met 'n oplossing van effektiewe mikroorganismes (EM) wat hoofsaaklik uit fotosinterende baterieë bestaan, het ook geen betekenisvolle effek op groei gehad nie. Die gevolgtrekking is gemaak dat toediening van organiese materiaal moonlik as plaasvervanger vir metielbromied-beroking kan dien in die beheer van AHS. Die nodige komposkwaliteit-standaarde moet egter eers geïmplimenteer word. Omdat feitlik geen kompos universeel effektief kan wees nie, is dit ook nodig dat verskillende tipes kompos met mekaar vergelyk moet word in spesifieke grondtoestande voordat verdere aanbevelings gemaak kan word. As gevolg van variërende resultate met biologiese beheer produkte kan AHS beheer met hierdie middels nie gewaarborg word op hierdie stadium nie en verdere studies word aanbeveel.
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Pamphilon, Lindsay Victoria. „The biological control of Myzus cerasi“. Thesis, University of Greenwich, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325268.
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Wigington, Ian. „The effect of water restrictions on apple orchard productivity in British Columbia's Okanagan Valley“. Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26666.
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This thesis examines the relationship between water and yield for apples in the Okanagan region of British Columbia. This is accomplished through a model which simulates the water/yield relationship in tree fruits. Two soil types, two rootstocks, and two irrigation systems were included in the simulation.
The results of the simulation indicate that Okanagan orchard irrigation water requirements are substantially lower than present irrigation application rates. Using sprinkler irrigation, irrigation requirements for silt-loam soils amounted to 30% of present application rates, while for sand soils 42% of present application rates were required. Trickle irrigation requirements were determined to be 71% of sprinkler requirements for similar yields.Land and Food Systems, Faculty of
Graduate
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Suwarni, Endah. „Pollen contamination, mating system, and genetic diversity in a Pinus merkusii seedling seed orchard“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ47103.pdf.
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Tsai, Ming-Yi. „The Washington orchard spray drift study : understanding the broader mechanisms of pesticide spray drift /“. Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8471.
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Morelli, Carla Dominica. „Engendering design--eliminating impediments to the creation of supportive housing models at Orchard Park“. Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/68763.
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Cordero-Irizarry, Patricia Marie. „Soil Carbon as A Soil Quality Indicator of A Fruit Orchard In Puerto Rico“. The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618594104520193.
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Berdeni, Despina. „Evaluating the potential of arbuscular mycorrhizal fungi for improving apple (Malus pumila) orchard sustainability“. Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/17456/.
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Developing agricultural systems which are able to balance productivity and sustainability is critical for ensuring future food security. Arbuscular mycorrhizal fungi (AMF) are an important component of the soil microbial community and play a vital role in a range of essential ecosystem functions. Arbuscular mycorrhizal symbiosis is characterised by the exchange of carbon from host plants in return for nutrients captured in the soil by the fungi, however AMF may also provide important non-nutritional benefits such as improving host plant resistance to pathogens. AMF are known to form symbiosis with over 80% of land plants including many major crop plants and have therefore received recognition as a potential tool for improving sustainability of agro-ecosystems. Apple is the fourth most widely planted fruit crop globally and is known to form symbiosis with AMF. The potential for AMF to improve orchard sustainability has been recognised by the cider apple industry and led to the overarching aim of this thesis which is to evaluate the potential benefits of AMF for cider apple production and sustainable management. Using the combination of a semi-controlled growth experiment and a landscape scale sampling approach, this study has examined the benefit AMF can provide to growth, health and productivity of cider apple trees. Understanding impacts of orchard management upon AMF communities has been a key aim of this work due to the increasing body of research reporting reduced abundance and functioning of AMF within intensively managed agricultural environments. This study has characterised AMF communities naturally found within three major cider apple orchard management types and investigated how AMF communities are impacted by aspects of orchard management. Results from this thesis provide evidence that AMF are able to provide disease resistance benefits to apple and are therefore beneficial to apple production. Furthermore data from this thesis shows that irrespective of management, cider apple orchards are able to host naturally diverse AMF communities which show similarities to the AMF communities of woodland. Results from this thesis have significant implications for orchard management and have highlighted several areas for potential future research.
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Rector, Ryan J., William B. McCloskey, Glenn C. Wright und Chris Sumner. „Citrus Orchard Floor Management 2001-2003: Comparison of a Disk, “Perfecta” Cultivator, and Weed Sensing Sprayer“. College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/198100.
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An optical weed sensing sprayer (WeedSeeker) was evaluated for making postemergence glyphosate herbicide applications in a Yuma, AZ lemon orchard. In addition, mechanical (disk and Perfecta cultivator) and chemical weed control strategies were compared. Results were fairly similar; however, the use of the WeedSeeker units combined with a preemergence herbicide (H1) increased weed control three fold compared to disking (D) and perfecta (P1). Additionally, when the WeedSeeker units were used in conjunction with preemergence herbicides, spray volume was reduced by 66% compared to a conventional sprayer and by 57% when used for postemergence applications only. There was a relationship between weed ground cover and the area sprayed by the WeedSeeker units indicating that maximum postemergence herbicide savings will occur at low weed densities or less than 10% groundcover. The use of a sprayer with an improved suspension system allowed for faster spraying speeds than were possible with the tractor mounted sprayer. Weed control was similar for the conventional and the WeedSeeker sprayer. However, yields were variable for both years. Future investigations will include efforts to develop crop budgets based on experimental operations
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Rattray, Michael. „An investment analysis of planting sweet cherries in Washington“. Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35285.
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Master of AgribusinessDepartment of Agricultural Economics
Mykel Taylor
Choosing a viable long-run crop investment can be risky and time consuming for farmers. The high establishment costs and risk for perennial tree crops like cherries require producers to conduct careful analysis prior to investing. Farmers must not only look to prices today but to the long term price trends that are likely affect the investment profitability. This thesis is an investment analysis on planting twenty-five acres of Sweetheart cherries in Washington State. The purpose is to calculate the total net present value over the commercially productive life of the cherry trees. Prices received by growers for sweet cherry production can fluctuate. Sweet cherries are also susceptible to yield volatility. Therefore, a sensitivity analysis was calculated that shows the changes in price and yield and its effect on net present value. Sweet cherry production for fresh market is also labor intensive. Changes in labor supply and minimum wage can affect a farmers profit margins. This thesis evaluates the risk of a wage shock to the total net present value of the investment. The net present value calculated was found to be positive, making planting Sweetheart cherries a viable option for Hillslide Orchards. The internal rate of return was favorable at 12.30% return. Yield risk was relatively low in this model showing positive net present values at 60% over base yield and still positive at 40% below base yields. The price risk was found to be slightly higher with negative net present values below $1.00 or 20% below the base price. It is important to note that this model represents planting a block of Sweetheart cherries within an existing operation. There are additional costs that would be incurred for other farm operations, not modeled here that could decrease the overall profitability under alternative planting scenarios.
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Nicholas, Adrian H., of Western Sydney Hawkesbury University und Faculty of Science and Technology. „The pest status and management of woolly aphid in an Australian apple orchard IPM program“. THESIS_FST_XXX_Nicholas_A.xml, 2000. http://handle.uws.edu.au:8081/1959.7/330.
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The thesis studied the biological control of woolly aphid (Eriosoma lanigerum Hausm.) using European earwig (Forficula auricularia L.) in an Australian apple orchard IPM program. Woolly aphid populations were monitored over the 1995/96 and 1996/97 growing seasons, completing a four year study of the pest's status and management under IPM programs at Bathurst in the Central Tablelands of NSW. Woolly aphid infestation in 2 IPM treatments, based on alternative control techniques for codling moth (Cydia pomonella L.), namely mating disruption and fenoxycarb, were compared with a conventional insecticide azinphos-methyl program. Further, the thesis studied the toxicity, to adult European earwigs, of chemicals commonly used in Australian apple orchards. The pesticide alpha-cypermethrin is highly toxic to weevil spp. and is used by apple growers in Western Australia for their control, but it is also toxic to earwigs. This trial investigated the potential of alpha-cypermethrin to disrupt the biological control of woolly aphid. Following a single application as a butt spray, alpha-cypermethrin suppressed the number of earwigs in apple trees for 14 weeks. The single application did not reduce earwig numbers to the extent that the biological control of woolly aphid was lost, however a full season program with applications every 14 to 21 days to all trees, as recommended to control weevils, within an orchard is likely to be very disruptive. The research also studied the control of woolly aphid using insecticide root-soil drenches. Imidacloprid provided excellent control of woolly aphid for 3 seasons. Pirimcarb provided some suppression of woolly aphid during the first season, but not in subsequent seasons. Chlorpyrifos and vamidothion failed to control woolly aphid in any season.Doctor of Philosophy (PhD)
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Svensson, Sven Axel. „Converging air jets in orchard spraying : influence on deposition, air velocities and forces on trees /“. Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-5818-8.pdf.
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Wennström, Ulfstand. „Direct seeding of Pinus sylvestris (L.) in the boreal forest using orchard or stand seed /“. Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6088-3.pdf.
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Nicholas, Adrian Harry. „The pest status and management of woolly aphid in an Australian apple orchard IPM program /“. View thesis, 2000. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030624.095814/index.html.
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Bradshaw, Terence L. „Comprehensive Assessment of Organic Apple Production in Vermont: Experience from Two Orchard Systems, 2006-2013“. ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/327.
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Despite substantial consumer demand and willingness to pay premium prices for organically grown fruit, apple growers in Vermont and other New England states have been slow to adopt certified organic practices. Barriers cited in the past to increased adoption of organic apple production in the region include susceptibility of traditionally grown cultivars to apple scab, lack of effective insect pest management materials, and few available effective options for fruit thinning. Recent changes in apple cultivar plantings in the region, introduction of new insect pest management materials, and advances in crop thinning justified an evaluation of organic apple production systems containing cultivars identified as important to the future of the apple industry. In 2006, two apple orchards were established at the University of Vermont Horticulture Research and Education Center in South Burlington, VT to comprehensively evaluate the five commercially-important apple cultivars of `Ginger Gold', `Honeycrisp', `Liberty', `Macoun', and `Zestar!' over eight growing seasons in two organically-managed orchard production systems, including a newly-planted high-density orchard (Orchard 1) and in an existing, medium-density orchard which was top-grafted to the new cultivars (Orchard 2). Parameters for tree growth and survival, crop yield, disease and arthropod pest incidence on foliage and fruit, and long-term economic return, including a twenty-year projection of net present value (NPV) of each cultivar in the two systems were evaluated in this study.
`Ginger Gold', despite high incidence of some diseases on foliage and fruit, performed the best in both orchard systems overall. The cultivar was among the cultivars with the highest measurements of tree growth. `Ginger Gold', along with `Honeycrisp', had the highest cumulative net crop yield per tree in Orchard 1 and the highest in Orchard 2. Notably, apple scab on `Honeycrisp' foliage and fruit and `Zestar!' fruit in both orchards was at a level that was not significantly different from `Liberty', a scab-resistant cultivar on which no scab was observed. However, `Honeycrisp' had the highest incidence of fruit rots in both orchards, but it was not significantly different than `Zestar!' in Orchard 1. Management of lepidopteran pests of fruit was a major challenge on all cultivars over the years of the study. For most of the tree growth parameters and cumulative net crop yield, `Liberty' was among the lowest group of cultivars in both orchards. Cumulative net crop yield of both `Macoun' and `Zestar!' were also among the lowest in both orchards with the top-grafted `Macoun' and `Zestar!' trees having significant tree death compared to the other cultivars in Orchard 2.
Harvested fruit were graded to commercial standards and cumulative gross and net income calculated from grade distribution, crop yield, and fruit price data. In Orchard 1, `Ginger Gold' and `Liberty' had greater cumulative gross income per hectare from 2006-2013, in excess of US$40,000, compared to `Liberty'. However, after management costs were deducted, all cultivars in Orchard 1 had negative cumulative net income of $-77,892 or less. In Orchard 2, all cultivars had positive cumulative net income for 2006-2013, and `Ginger Gold' had the highest at $109,717/ha. The twenty-year projected NPV was negative for all cultivars in Orchard 1, but in Orchard 2, all cultivars had positive NPV with `Ginger Gold' having the highest among the cultivars.
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McCloskey, William B., Glenn C. Wright und Christopher P. Sumner. „Citrus Orchard Floor Management 2001: Comparison of a Disk, "Perfecta" Cultivator, and Weed Sensing Sprayer“. College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/223672.
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Mechanical (disk and Perfecta cultivator) and chemical weed control strategies were compared in a Yuma, AZ lemon orchard. In addition, an optical weed sensing sprayer (WeedSeeker) was evaluated for making post-emergence Roundup Ultramax herbicide applications. The use of pre-emergence herbicides in conjunction with the WeedSeeker spray units has the potential to significantly reduce the amount of post-emergence herbicide and water needed to spray flood irrigated citrus orchards. There was a relationship between weed ground cover and the area sprayed by the WeedSeeker units that indicated the maximum herbicide saving will occur a low weed densities. The use of the Kawasaki Mule with its superior suspension system allowed for faster spraying speeds than were possible with the tractor mounted sprayer and this also reduced spray volume per plot. Weed control was similar for the conventional and the WeedSeeker sprayers. Future investigations will include efforts to improve the estimation of percent weed groundcover, the use of higher rates of pre-emergence herbicides and the development of crop budgets based on experimental operations.
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Krüger, Johanna Alida. „The Cherry Orchard transposed to contemporary South Africa : space and identity in cultural contexts / J.A. Krüger“. Thesis, North-West University, 2009. http://hdl.handle.net/10394/5001.
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The transposition of Chekhov's The Cherry Orchard (originally published in Russian in 1904) to contemporary South Africa in Suzman's The Free State (2000) is based on the corresponding social changes within the two contexts. These social changes cause a binary opposition of past and present in the two texts. Within this context memory functions as a space in which the characters recall the past to the present and engenders a dialogue between past and present. Memory is illustrated in the two plays by associations with place as an important aspect of identity formation. Memory and place are fused in the plays by means of Bakhtin's concept of the chronotope which is best observed in the plays in memories of specific places such as the respective orchards, houses and rooms such as the nursery and the ballroom in. The Cherry Orchard and the garden in The Free State. Furthermore, the influence of the past is also evident in the present when ideas of social status, class, race (in the case of The Free State) and behaviour are contrasted and when various characters express their perceptions of personal relationships and ideas about marriage. The influence of the past is also evident when the characters voice their different perceptions and expectations of the past and future. In The Cherry Orchard these cultural differences are evident in the concept of heteroglossia. However, in The Free State, these dialogues are directed by a specific politically liberal view which diminishes the heteroglossia in the text. The juxtaposing of past and present is also illustrated in The Cherry Orchard by various subversive strategies such as comedy of the absurd in order to portray the behaviour of the characters as incongruous. Another subversive strategy is the contrasting of characters and ideas in order to expose pretensions and affectations in speech and actions to parody both the old establishment and the ambitions of former peasants. These conventions are best illustrated by the concept of the carnivalesque that also features as one of Bakhtin's terms to capture incongruous ideas and situations in literature. In The Free State, comedy is unfortunately much diminished and in contrast to Chekhov's ambiguity, only directed against politically conservative characters. The prevalence of these three Bakhtinian concepts in the texts shows how identity formation is to a large extent influenced and defined by occupied space. When social change affects the distribution of land, a character's concept of identity is destabilised. Although Suzman uses this similarity in the two contexts in order to transpose Chekhov's text to contemporary South Africa, she organises the various stances in the text to advocate a specific politically liberal view. Thus, Suzman's transposition leads to an interesting comparison between the Russian and South African contexts as well as between the two texts. However, her text is limited by her political interpretation of Chekhov's text.Thesis (M.A. (English))--North-West University, Potchefstroom Campus, 2009.
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Royauté, Raphaël. „Factors influencing behavioural variation in apple orchard populations of the jumping spider «Eris militaris» (Araneae: Salticidae)“. Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123173.
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Behavioural differences between individuals are often consistent over time (personality traits) and correlated across multiple behavioural contexts (behavioural syndromes). These individual differences are ubiquitous across taxa and have far-reaching implications for ecology and evolution: determining the mechanisms maintaining them is central to behavioural ecology. These individual differences vary along ecological gradients and can be affected by human-induced environmental changes. Agroecosystems vary considerably in their intensity and frequency of human disturbances and are suitable systems to study alteration and modification of behavioural responses by individuals. Many beneficial arthropods, such as spiders, can be negatively affected by different management practices, notably the use of insecticides. In this thesis, I explore the determinants of individual behavioural variation in the context of agroecosystems, using the jumping spider Eris militaris (Araneae: Salticidae) as a model organism. My focus on spiders is motivated by their importance in agroecosystems as generalist predators. In addition, spider personality traits and behavioural syndromes are well described in the literature. I tested whether behavioural syndromes varied between populations with different histories of insecticidal exposure, how consistent behavioural correlations were through ontogeny and how sublethal exposure to insecticides disrupted behavioural consistency and correlations. I found evidence for differing behavioural syndromes between spider populations from insecticide-free and insecticide-treated apple orchards. Individuals with highest activity and voracity had low aggression and boldness in the insecticide-free population while aggressive and voracious individuals behaved less boldly in the insecticide-treated population. These two populations had differing age-structure as more juvenile stages were collected in the insecticide-treated population leading to investigate further the role of development in the generation of behavioural syndromes and consistent behavioural tendencies. When taking development into account, I found that behavioural tendencies were not strongly maintained over the course of ontogeny and only activity showed evidence of heritability and repeatability. I found strong evidence for ontogenic shifts in behavioural syndrome during the transition from subadult to adult stages, mediated by rearing environment and sex. Behavioural correlations were mostly underpinned by within-individual variation indicating high behavioural plasticity through ontogeny. These results confirm that the differences in syndrome structure found between the two apple orchard populations may in part be generated by ontogenic shifts and lower abundance of adult stages in the insecticide-treated population.I performed direct insecticidal exposure tests to determine the effects of sublethal disruption on the consistency and correlation of behavioural traits. Exposure to the organophosphate phosmet at a sublethal dose had a stronger effect on the repeatability of activity than on its average value, indicating that individuals react differently to insecticide exposure. I found strong alterations on the correlations between activity and prey capture that were more pronounced in females. This research provides an opportunity to bridge the gaps between animal personality, agroecology and ecotoxicology by focusing on suites of related traits that affect spider performance in agroecosystems.Les différences comportementales entre individus sont souvent stables au cours du temps (traits de personnalité) et en de multiples contextes (syndromes comportementaux). Ces différences sont communes à de nombreux taxons et ont de profondes implications pour l'écologie et l'évolution. Déterminer les mécanismes maintenant ces variations est un aspect central de l'écologie comportementale. Ces différences varient également le long de gradients écologiques et peuvent être affectées par les changements anthropiques.Les agroécosystèmes varient dans leur intensité et fréquence de perturbations humaines et sont des systèmes adéquats pour l'étude des altérations de la réponse comportementale des individus. De nombreux arthropodes, tels les araignées, sont affectés par les pratiques culturales, notamment par l'utilisation d'insecticides. Au cours de cette thèse, j'examine les facteurs déterminant la réponse comportementales des individus dans les agroécosystèmes à l'aide l'araignée sauteuse Eris militaris (Araneae : Salticidae). Mon intérêt pour les araignées en tant que système d'étude est motivé par leur rôle de prédateur généraliste en agroécosytèmes. De plus, les traits de personnalité et les syndromes comportementaux des araignées sont bien décrits dans la littérature. J'ai testé la présence de variations de syndromes comportementaux entre populations ayant différents niveaux d'exposition aux insecticides, la stabilité de ces corrélations au cours du développement ainsi que les effets d'une exposition sublétale sur la stabilité des traits comportementaux et leurs corrélations.J'ai mis en évidence la présence de syndromes comportementaux différents chez des populations non exposées et exposées aux insecticides en vergers de pommiers. Les individus les plus actifs et voraces ont fait preuve d'une agressivité et témérité réduite chez la population non-exposée tandis que les individus agressifs étaient également voraces dans le verger exposé mais avec une témérité diminuée. Ces deux populations ont montré des différences marquées dans leur structure démographique puisque seuls des stades juvéniles ont été collectés dans le vergers exposé aux insecticides. Ceci m'a conduit à étendre mon investigation au rôle joué par le développement dans la génération des syndromes comportementaux.En prenant en compte le développement, j'ai montré que les tendances comportementales étaient faiblement maintenues et seule l'activité a montré des preuves d'héritabilité et de répétabilité. J'ai également découvert la présence de changement ontogénique de syndromes comportementaux, variant selon l'environnement d'élevage et le sexe lors de la transition du stade subadulte à adulte. Les corrélations comportementales ont été majoritairement influencées par les variations intra-individuelles, suggérant une forte plasticité comportementale au cours du développement. Ces résultats confirment le fait que les différences de structure des syndromes comportementaux entre populations en vergers de pommiers sont en parti dues aux transitions ontogéniques et à une abondance réduite des stades adultes dans la population exposée aux insecticides.J'ai ensuite réalisé une expérience d'exposition directe aux insecticides afin de déterminer les effets d'une perturbation subléthale sur la stabilité des traits comportementaux et leurs corrélations. L'exposition à l'organophosphate phosmet a eu un plus grand effet sur la répétabilité de l'activité que sur sa moyenne, indiquant des réponses variables à l'exposition insecticide d'individus à individus. J'ai également observé une altération plus prononcée des corrélations comportementales entre traits relatifs à l'activité et la capture de proies chez les femelles.Ces recherches permettent de combiner les expertises relatives aux domaines de la personnalité animale, de l'agroécologie et de l'écotoxicologie en se focalisant sur des traits comportementaux affectant la performance des araignées dans les agroécosystèmes.
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Vargas, Andrew. „A Case of Specifying and Using Networked Computers in the Sound Design for THE CHERRY ORCHARD“. Thesis, University of California, San Diego, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10063688.
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For theatre sound design, detailed planning of networked hardware and software affords a sound designer and the audio crew efficiency and flexibility during the process of rehearsals, designer quiet time, technical rehearsals, and performances. The need to property specify and use networked computers is demonstrated in the corresponding documentation within the portfolio of the sound design for The Cherry Orchard by Anton Chekhov. This play, which was produced by the UCSD Department of Theatre and Dance, opened in the Sheila and Hughes Potiker Theatre on November 29, 2015. The audio system and sound design process used current network technologies and practices to automate tasks, provide ease of access and control, and display information with better clarity and speed. The description of my experience as sound designer in this production of The Cherry Orchard, and the included portfolio documentation, is an example for theatre sound designers to take advantage of computer network technologies that are involved in the audio reinforcement system and sound design process of a theatrical production.
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Fireman, Naomi. „Oberlin's Experimental Hazelnut Orchard: Exploring Woody Agriculture's Potential for Climate Change Mitigation and Food System Resilience“. Oberlin College Honors Theses / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1559171019286324.
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Mansfield, Gwen. „Experiment Station Road“. ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/358.
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Experiment Station Road is an original work of fiction serving as a collection of short stories set in Hayford, Oregon and Las Vegas in 1962-1972. Each story presents the point of view of a resident in Hayford. The stories are written to function independently, but when read as a collection present insight to cultural diversity, intricate relationships and the ignorance of prejudice.