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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

MOSCAS-DAS-FRUTAS (DIPTERA: TEPHRITOIDEA) EM UM POMAR EXPERIMENTAL NO ESTADO DE MATO GROSSO DO SUL: DIVERSIDADE, DINÂMICA POPULACIONAL, RELAÇÕES COM HOSPEDEIROS E FATORES AMBIENTAIS

Sanches, Sonia de Oliveira Silva 19 March 2008 (has links)
Made available in DSpace on 2016-02-26T14:53:12Z (GMT). No. of bitstreams: 1 SoniaOliveiraSilvaSanches.pdf: 463782 bytes, checksum: a3bfcc82e0fdf99765bd05dba8ecc8a6 (MD5) Previous issue date: 2008-03-19 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fruit flies (Diptera: Tephritoidea) in a mixed orchard at the brazilian Mid-Western: diversity, population dynamics, host relationship and environmental factors. The knowledge about species composition of fruit fly in the Mid-Western Region of Brazil is scarce. The aim of this paper is to evaluate the population dynamics of fruit fly species in a mixed orchard with 21 fruit tree species (22º 13 16 S e 54º 48 20 W) in the campus at Federal University of Grande Dourados (UFGD), Dourados-MS. The survey was carried out during two consecutive years of sampling (May 2005 to June 2007). A total of 14 McPhail traps, baited with the Bio Anastrepha® food attractant, were hung up in the branches of 14 fruit tree species. Some 11,775 fruit flies adults were caught belonging to eight genera: Anastrepha Schiner (1868), Ceratitis MacLeay (1868), Hexachaeta Loew (1873), Tomoplagia Coquillett (1910) and Blepharoneura Loew (1873) (Tephritidae); Dasiops Rondani (1856), Lonchaea Fallén (1820) and Neosilba McAlpine (1962) (Lonchaeidae). The result shows that the hosts with higherinfestations by fruit flies in the orchard, were: starfruit (Averrhoa carambola L.) and guava (Psidium guajava L.), with the infestation indexes (larvae/kg) of 101.60 and 41.12, respectively. A. obliqua was the predominant species, in both, traps and fruits / Na região Centro-Oeste do Brasil são escassos os trabalhos de pesquisa sobre a composição de espécies de moscas-das-frutas. O objetivo deste trabalho foi avaliar a dinâmica populacional das espécies de moscas-das-frutas em um pomar no Centro-Oeste brasileiro (Universidade Federal da Grande Dourados - UFGD, Dourados-MS). Em quatorze armadilhas McPhail (iscadas com a atrativo alimentar Bio Anastrepha®) foram capturados 11.775 indivíduos em dois anos de coletas (maio de 2005 a junho de 2007). As espécies identificadas pertencem a oito gêneros: Anastrepha Schiner (1868), Ceratitis MacLeay (1868), Hexachaeta Loew (1873), Tomoplagia Coquillett (1910) e Blepharoneura Loew (1873) (Tephritidae) e Dasiops Rondani (1856), Lonchaea Fallén (1820) e Neosilba McAlpine (1962) (Lonchaeidae). Os resultados obtidos indicam que os hospedeiros mais infestados por moscas-das-frutas no pomar da UFGD, foram: carambola (Averrhoa carambola L.) e goiaba (Psidium guajava L.), com índices de infestação (larvas/kg) de 101,60 e 41,12, respectivamente. A. obliqua foi a espécie predominante, tanto nas armadilhas quanto nos frutos
52

Porovnání cen ovocných dřevin zjištěných zjednodušeným a výnosovým způsobem v okrese Hodonín / Compare prices for fruit trees found yield and simplified way in the district Hodonín

Kapounová, Radka January 2013 (has links)
The aim of diploma thesis is comparison prices for fruit trees found yield way and prices found simplified way. Comparison wil be made with selected fruit trees lokated in different areas in the distrikt Hodonín. In the three (four) lokations will be changed the age of trees and there will be monitored effect on price. The first part of thesis defines neceessary concepts and the basic knowledge about fruit trees. In the second part there is making valuation, comparison values in differrent lokations and there is making an assessment of individual methoods.
53

Nutrición de frutales: Necesidades y desequilibrios nutricionales

El Jendoubi, Hamdi 13 April 2012 (has links)
El present treball tracta de nocions fonamentals en la nutrició d’arbres fruiters: (i) estimació de les pèrdues totals de nutrients (ii) diagnòstic nutricional (iii) solucions per desordres nutricionals (iv) estudi de transport de nutrients. Els estudis s’han realitzat a la zona de l’Ebre, Saragossa, al nord d’Espanya on el presseguer s’escull com a exemple d’arbre fruiter i la clorosi fèrrica com exemple de desordre nutricional. En alguns estudis, s’han fet servir plantes model crescudes en condicions controlades. En el primer capítol dels resultats, es fa una anàlisi de l’arbre sencer a mitjançant la quantificació de les pèrdues de nutrients en cada esdeveniment del cicle anual del presseguer, i de les quantitats emmagatzemades a les estructures permanents dels tres cultivars de presseguer: Calanda, Catherina y Babygold 5. Al segon capítol, es considera la clorosi fèrrica com el típic desordre nutricional de la zona, i es presenten avenços al seu diagnòstic a través de l’estudi de materials de l’arbre en èpoques fenològiques avançades (precoces), com gemmes en dormància i flors. Els resultats obtinguts indiquen que és possible predir la clorosi fèrrica utilitzant els materials vegetals indicats. El tercer capítol, tracta sobre la utilització de fertilitzants foliars per la correcció de la clorosi fèrrica, millorant el coneixement científic en l’ús d’aquests fertilitzants foliars. S’avalua la eficàcia d’un tractament foliar d’un compost de ferro estudiant la seva capacitat de penetració i reverdiment. En el quart capítol, es realitzen estudis sobre el transport de ferro en el teixit del xilema, a través d’anàlisis de proteòmica i metabolòmica, aportant avenços en la comprensió d’aquest teixit, responsable del transport de nutrients en plantes. El cinquè capítol tracta sobre consells i aspectes a considerar per part dels investigadors a l’hora de realitzar un seguiment de l’efecte d’un fertilitzant de ferro, i que inclouen: (i) el disseny experimental (ii) el seguiment de l’evolució de la correcció de la clorosi després d’una fertilització amb ferro, controlant la concentració de clorofil•la a la fulla, i (iii) l’anàlisi de la resposta de la planta després d’una fertilització amb ferro. A més, també s’analitzen les fases de la desaparició de la clorosi a la fulla, i l’observació d’altres paràmetres nutricionals a nivell de fulla. / El presente trabajo trata sobre nociones fundamentales en la nutrición de árboles frutales: (i) estimación de las pérdidas totales de nutrientes (ii) diagnostico nutricional (iii) soluciones para desordenes nutricionales (iv) estudio del transporte de nutrientes. Los estudios se han realizado en la zona del Ebro, Zaragoza, en el norte de España dónde el melocotonero se escoge como ejemplo de árbol frutal, y la clorosis férrica como ejemplo de desorden nutricional. En algunos estudios, se han usado plantas modelo crecidas en condiciones controladas. En el primer capítulo de los resultados, se realiza un análisis del árbol entero mediante la cuantificación de las pérdidas de nutrientes en cada evento del ciclo anual del melocotonero, y de las cantidades almacenadas en las estructuras permanentes de tres cultivares de melocotonero: Calanda, Catherina y Babygold 5. En el segundo capítulo, se considera la clorosis férrica como el típico desorden nutricional de la zona, y se presentan avances en su diagnostico mediante el estudio de materiales del árbol en épocas fenológicas avanzadas (precoces), tal como yemas en dormancia y flores. Los resultados adquiridos indican que es posible predecir la clorosis férrica usando los materiales vegetales indicados. El tercer capítulo, trata sobre del uso de fertilizantes foliares para la corrección de la clorosis férrica, mejorando el conocimiento científico sobre el uso de dichos fertilizantes. Se evalúa la eficacia de un tratamiento foliar de un compuesto de hierro estudiando su capacidad de penetración y reverdecimiento. En el cuarto capítulo, se realizan estudios sobre el transporte de hierro en el tejido de xilema a través de análisis de proteomica y metabolómica, aportando avances en la comprensión de dicho tejido, responsable de transporte de nutrientes en plantas. El quinto capítulo trata sobre consejos y aspectos a considerar por parte de los investigadores a la hora de realizar un seguimiento del efecto de un fertilizante de hierro, y que incluyen: i) el diseño del experimento; ii) el seguimiento de la evolución de la corrección de la clorosis después de una fertilización con hierro, controlando la concentración de clorofila en la hoja; y iii) el análisis de la respuesta de la planta después de una fertilización con hierro. Asimismo, también se analizan las fases de la desaparición de la clorosis en la hoja, y la observación de otros parámetros nutricionales a nivel de hoja. / This work deals with fundamental aspects of fruit tree nutrition, including the following: (i) estimation of total nutrient requirements; (ii) nutritional diagnostics; (iii) remediation for nutritional disorders; and (iv) understanding of nutrient transport. Field studies were carried out in the Ebro river basin, Zaragoza, Northern Spain, were peach tree was taken as an example of fruit tree and Fe chlorosis as an example of nutritional disorder. In some studies, model plants grown in controlled environments have also been used. In the first chapter of Results part, whole tree analysis was carried out by quantifying the amounts of nutrients removed at each event of the peach tree annual cycle, as well as the amounts stored in the permanent tree structures, in three different peach tree cultivars. In the second chapter, Fe chlorosis was taken as a typical nutrient disorder in the region, and we show advances in its diagnosis by studying the possibility of using tree materials in early tree phonological stages. Results found indicate that it is possible to carry out the prognosis of Fe chlorosis using early materials such as buds and flowers. The third chapter deals with the correction of iron chlorosis, in an attempt to improve the scientific background for foliar fertilizer practices. We evaluated the success of treatments with a Fe compound by studying the capacity for penetration and re-greening. In the fourth chapter, studies on the transport of Fe into the xylem tissue were carried out by metabolomic and proteomic analysis, opening the way for advancing the understanding of nutrient transport in this fruit tree compartment. The fifth chapter discusses advices and aspects that researchers should take in consideration when assessing the effect of Fe fertilizers, including the following: i) design of Fe-fertilization experiments; ii) assessment of chlorosis recovery upon Fe-fertilization by monitoring leaf chlorophyll; and iii) analysis of the plant responses upon Fe-fertilization. The phases of leaf chlorosis recovery and the control of other leaf nutritional parameters were discussed.
54

Utilisation of indigenous fruit by rural communities in Mwanza District, Malawi

Chilimampunga, Francis Harvey 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Deforestation in Malawi is said to reach 2.3% per annum and negatively affects agricultural production, the backbone of the country's economy. High dependence on indigenous wood for sale as fuelwood or charcoal by rural communities due to poverty largely contributes to this deforestation. Women and children suffer most because they spend more time collecting firewood than men, affecting other activities like child-care and education. The study, aimed at investigating ways to alleviate deforestation by increasing rural people's economic benefits from non-destructive indigenous fruit utilisation, was conducted in Mwanza District from February to June 2001. The district's customary forests which contain a wide variety of wild fruit species are currently deforested due mainly to charcoal production. Five out of 16 villages facing deforestation were randomly chosen by the lottery method. Group, individual and key informant interviews focused on the utilisation of preferred fruit species by communities while participatory resource assessment was used to determine availability and distribution of fruit trees. A market survey to assess fruit trade in the country was conducted in Balaka, Blantyre, Mangochi, Mwanza and Zomba Districts in early June 2001. Twenty-six wild fruit species were found to be utilised by villagers in the study area but Adansonia digitata (Baobab) was the most commonly found near villages and the most preferred fruit by 90% of respondents. Other preferred species were Tamarindus indica (Tamarind), Diospyros kirkii, Flacourtia indica and Vangueria infausta. Most fruit trees except for baobab were found to be of small size classes because of being young stems regenerating while others were shrubs. The poor largely depended on fruit as a meal and for sale. Mainly children and women sold baobab and tamarind within the villages while only men sold fruit at distant markets for more income. Middlemen largely benefited from fruit sales compared to villagers who sold at low prices and lacked marketing information. Fruit rot affected retailers outside the study area. Tree climbing to harvest fruit was mainly done by boys and destructive harvesting methods were associated with commercial use. Large, sweet tasting fruit were mainly chosen by rural communities for subsistence use. Land clearance, mast fruiting, perishability and seasonality of fruit seemed to have affected harvest both for subsistence and for sale. However, 89% of households owned fruit trees in homesteads and agricultural fields, said to be more protected than in communal lands with open access. Preferred wild fruit trees were rarely cut by the communities. Local fruit processing, mainly by women, included porridge and juice making and fruit drying while careful storage enabled baobab fruit to be stored for up to a year. Wild fruit plays an important role in the lives of rural communities mainly the poor. Communities attach value to the preferred fruit species but it is difficult to convince most of them to sell wild fruit unless value is added and price incentives are initiated. Regular marketing information could be provided to rural communities and policy makers should set fruit pricing guidelines to create price incentives. Domestication of the preferred fruit trees should be encouraged for continuous fruit supply. Simple fruit processing technologies for commercial purpose could be initiated for women mostly. Research is needed to determine sustainable harvesting levels of wild fruit and ways for participatory monitoring of the levels and harvesting methods used. / AFRIKAANSE OPSOMMING: Ontbossing in Malawi beloop 2.3% per jaar, wat beteken dat landbouproduksie, die ruggraat van die land se ekonomie, negatief geaffekteer word. Wat grootliks bydra tot hierdie ontbossing is dat die plattelandse gemeenskappe as gevolg van armoede hoogs afhanklik is van inheemse hout wat as brandhout of as houtskool verkoop word. Vroue en kinders ly die meeste omdat hulle meer tyd as mans spandeer om vuurmaakhout bymekaar te maak. Dit affekteer ander aktiwiteite soos kindersorg en opvoeding. Hierdie studie het ten doelom maniere te ondersoek waarvolgens ontbossing verlig kan word deur mense op die platteland se ekonomiese voordele uit die benutting van inheemse vrugte te vermeerder sonder dat daar enige omgewingskade aangebring word. Die studie is uitgevoer in die Mwanza Distrik vanaf Februarie 2001 tot Junie 2001. Die distrik se inheemse bosse wat 'n wye verskeidenheid wilde vrugtespesies bevat, word tans ontbos - hoofsaaklik as gevolg van die produksie van houtskool. Vyf uit die 16 dorpies wat ontbossing in die gesig staar, is op 'n lukrake wyse met die loterymetode gekies. In die onderhoude met groepe, individue, en sleutelinformante is gefokus op die benutting van vrugtespesies wat deur die gemeenskappe verkies word. Hulpbronevaluering is gebruik om die beskikbaarheid en verspreiding van vrugtebome te bepaal. Die gemeenskap is by hierdie evaluering betrek. Marknavorsing om vrugtehandel in die land te evalueer, is vroeg in Junie 2001 in die Balaka, Blantyre, Mangochi, Mwanza en Zomba distrikte gedoen. In die studie is bevind dat die inwoners van die area wat bestudeer is 26 wilde vrugtespesies benut. Adansonia digitata (Baobab/Kremetartboom) is egter die meeste naby die dorpies aangetref, en is deur 90% van die respondente as hulle gunsteling vrug aangedui. Ander gewilde spesies is Tamarindus indica (Tamarinde/Suurdadelboom), Diospyros kirkii, Flacourtia indica en Vangueria infausta. Die meeste vrugtebome, behalwe die baobab, val in die laer klasse wat grootte betref, omdat dit die jong lote is wat regenereer, terwyl ander struike is. Die arm mense is grootliks afhanklik van vrugte as 'n maaltyd en as verkoopsartikels. Hoofsaaklik kinders en vroue verkoop baobab- en tamarindevrugte in die dorpies, terwyl vrugte by verafgeleë markte slegs deur mans vir 'n groter inkomste verkoop word. Die middelman trek grootliks voordeel uit vrugteverkope, in vergelyking met die inwoners van die dorpies wat vrugte teen lae pryse verkoop as gevolg van 'n tekort aan bemarkingsinligting. Kleinhandelaars buite die studie-area is deur vrugteverrotting geaffekteer. Dit is hoofsaaklik seuns wat die bome klim om vrugte te oes, en destruktiewe oesmetodes is met kommersiële gebruik geassosieer. Plattelandse gemeenskappe verkies hoofsaaklik groot, soet vrugte vir bestaansgebruik. Dit wil voorkom of grondopruiming, die vrugvorming van byvoorbeeld akkers (mast fruiting), die bederfbaarheid en seisoensgebondenheid van vrugte, die oes affekteer vir bestaansgebruik sowel as vir verkope. Vrugtebome word egter deur 89% van die huishoudings besit en die bome by hierdie huise en in landbouvelde word beter beskerm as dié in gemeenskaplike lande met vrye toegang. Die gemeenskappe kap selde hulle gunsteling wilde vrugtebome uit. Plaaslike vrugteverwerking, hoofsaaklik deur vroue, sluit in die maak van pap en sap, asook die droog van vrugte, terwyl sorgvuldige bewaring daartoe kan lei dat baobabvrugte vir tot 'n jaar lank gebêre kan word. Wilde vrugte speel 'n belangrike rol in die lewens van plattelandse gemeenskappe, veral vir die armes. Die gemeenskappe heg waarde aan hulle gunstelingvrugtespesies, maar dit is moeilik om die meeste te oortuig om wilde vrugte te verkoop - behalwe as waarde bygevoeg word en prysaansporings ingestel word. Gereelde bemarkingsinligting kan aan plattelandse gemeenskappe voorsien word, en beleidbepalers behoort riglyne vir vrugtepryse daar te stelom prysaansporings te skep. Die mense behoort aangemoedig te word om hulle gunstelingvrugtebome by hulle huise te plant om 'n voortdurende vrugtevoorraad te verseker. Eenvoudige vrugteverwerkingtegnologie kan vir kommersiële doeleindes vir hoofsaaklik vroue ingestel word. Navorsing is nodig om volhoubare oesvlakke van wilde vrugte te bepaal, sowel as maniere vir die deelnemende monitering van hierdie vlakke en die oesmetodes wat gebruik word.
55

Nutrient requirement and distribution of intensively grown ‘Brookfield Gala’ apple trees

Kangueehi, Grace Nandesora 03 1900 (has links)
Thesis (MscAgric (Horticulture))--University of Stellenbosch, 2008. / ‘Brookfield Gala’ apple trees were planted out in July 2003 in a Dundee soil form, consisting of well-aerated sandy loam soil. During the first 12 months trees received young tree solutions high in nitrogen. The nutrient solution of the 2nd leaf trees was based on a yield estimation of 10 ton. ha-1 plus 30%. Nutrient solutions for the 3rd leaf trees were based on 25 ton. ha-1 yield estimations and adapted upwards. Seasonal uptake and distributions were determined for macro and micro elements, using twoand three-year-old apple trees during the seasons 2004/2005 and 2005/2006. In the bearing apple trees the macro nutrient accumulated rapidly from late winter to late autumn. Prior to leaf drop most of the N, P, S, Mg and a small portion of K were redistributed back into the permanent parts of the tree. On the other hand, all Ca in the leaves was lost through leaf drop. Apple fruit contains comparatively large quantities (±60.2%) of K, which are removed during harvest. Guidelines for minimum and maximum nutritional requirements based on the amount necessary to produce 1 kg fruit were determined. For the 3rd leaf trees the minimum macro nutrient requirements (g. kg-1 yield) of N, P, K, Ca, Mg and S were ±1.7, ±0.3, ±2.3, ±0.5, ±0.2 and ±0.2, respectively. The maximum nutrient requirements (g. kg-1 yield) for N, P, K, Ca, Mg and S were ±2.6, ±0.4, ±3.3, ±1.9, ±0.4 and ±0.2, respectively. For the 3rd leaf trees the minimum micro nutrient requirements (mg. kg-1 yield) of Na, Mn, Fe, Cu, Zn, B and Mo were ±75.1, ±1.3, ±28.7, ±0.9, ±3.0, ±5.7 and ±0.3, respectively. The maximum nutrient requirements (mg. kg-1 yield) of Na, Mn, Fe, Cu, Zn, B and Mo were ±102.9, ±7.8, ±32.6, ±1.1, ±6.5, ±7.6 and ±0.3, respectively. Labelled N uptake and distribution for two- and three-year-old apple trees were also determined during the same seasons. The labelled N uptake and distribution results indicated that there was a low labelled N uptake in the initial growth stages, suggesting the importance of internal N reserves for plant development at the beginning of the season. In the active growing period more than 60% of the labelled N was found in the new growth. Uptake efficiency improved as the trees grew older. The effect of different nutrient levels on tree growth, yield and fruit quality was assessed: lower (80%) than the standard (100%) and three higher (120%, 140% and 160%). Results indicated that different nutrient levels had no effect on yield, blush or TSS during the 18 months of application over two bearing seasons. The application of biological products (humic acid, and compost plus compost extract) over a period of 18 months had a significant influence on the TSS, malic acid and citric acid concentrations. A tendency towards an increase in total fine root number and length occured with the addition of biological ameliorant.
56

Porovnání cen ovocných dřevin zjištěných zjednodušeným a výnosovým způsobem / Comparison of Fruit Trees Prices Ascertained by the Simplified and Yield Method

Jašová, Alena January 2012 (has links)
The Thesis „Comparison of fruit trees prices ascertained by the simplified and yield method“ deals with the comparison of both pricing methods, where there are defined factors on the basis of ascertained facts which have essential influence on price difference of fruit trees and subsequently the proposal to their modification is made.
57

Landscape preservation and biodiversity planning : the Kino Heritage Fruit Trees Project and beyond

Yaquinto, Robert Giacomo 01 October 2014 (has links)
This report argues that historic landscape preservation efforts need to embrace biodiversity planning. Historic landscape preservation sites need to develop biodiversity plans because they are uniquely qualified to provide the continuous monitoring that successful biodiversity planning requires. Not only will biodiversity monitoring at various historic landscape sites contribute to a nationwide collection of biodiversity planning data, but it will also provide a rich source of information that can be presented to draw a wider audience into the biodiversity discussion. After considering three precedents: Old Sturbridge Village, Old World Wisconsin, and Tucson Botanical Gardens, the report focuses on the Kino Heritage Fruit Trees Project and its real and potential impacts on biodiversity planning in southern Arizona and more broadly. Finally, the report considers how seed libraries and seed swaps might serve a similar purpose in other parts of the country. / text
58

The role of indigenous fruit trees in the rural livelihoods : a case of the Mwekera area, Copperbelt province, Zambia

Kalaba, Felix Kanungwe 12 1900 (has links)
Thesis (MSc (Forest and Wood Science))—University of Stellenbosch, 2007. / The utilization and commercialization of indigenous fruit trees has in the past been overlooked by extension agencies due to the misconception that they do not play a major role in contributing to the rural livelihoods. There is new and increasing emphasis on the contribution of non-timber forest products (NTFPs) on improving the livelihoods and sustainable management of forest ecosystems of the Miombo woodlands. This study was conducted around Mwekera area in the Copperbelt province, Zambia to determine the role of indigenous fruit trees in the rural livelihoods. A total of 70 households were interviewed in the survey using semi-structured questionnaires, in-depth open ended interviews and focus group meetings to collect information on the use of indigenous fruits. The study revealed that 99% of the households experience ‘hunger’ during the rainy season from November to April every year. Ninety seven percent (97%) of the households collect indigenous fruit, with the most collected fruits being Uapaca kirkiana (74%), Anisophyllea boehmii (71%) and Parinari curatellifolia (67%). Additionally, there is very little selling of indigenous fruit (31%) but that Uapaca kirkiana and Anisophyllea boehmii account for 95% of the fruits sold. Forty six percent (46%) of the households process fruits of U. kirkiana, A. boehmii and P. curatellifolia into juice and/or porridge. Furthermore IFTs are also used as traditional medicine. Sixty three percent (63%) of the households used IFTs for medicinal purposes with two-thirds of the respondents citing Anisophyllea boehmii as an important medicinal tree species. The study also showed that 85% of the respondents have seen a change in the forest cover resulting into loss of biodiversity with 70% of the respondents indicating that the change is with respect to reduction in forest size and scarcity of some species; and that charcoal production and clearance of land for cultivation are the major causes of the scarcity of indigenous fruit trees. It is concluded that the major contribution of IFTs in the study area is in filling the gap during times of hunger rather as being a source of income through selling. Charcoal production and clearance for agriculture are the main contributing agents for the loss of biodiversity and scarcity of IFTs. It is recommended that domestication of IFTs and sustainable forestry and agricultural management practices be employed to ensure that future generations continue to benefit from the forest resource.
59

Yield and quality of pomegranate on selected geographical areas in Western Cape Province, South Africa

Mashavhathakha, Khathutshelo Logan 09 1900 (has links)
The pomegranate fruit is one of the high valued crops, but there is insufficient information regarding the fruit properties in South Africa. The aim of the study was to evaluate the physico-chemical properties as well as total phenols, anthocyanin, antioxidant, organic sugars and acids of cultivar Wonderful on three locations of the Western Cape. This study was conducted on mature pomegranate fruits harvested in the 2012 and 2013 seasons. Fruit weight (g), length (mm), and width (mm), peel/aril colour and total arils weights (g) were measured. Fruits were also analysed for total soluble solids (TSS) or °Brix), titratable acidity (TA) and juice pH. Results of the study showed that there were significant differences in all measured factors with the exception of % aril yield between the three locations. Though varied per season, fruits produced at Bonnievalle had better physical and chemical properties than at the other localities. With the exception of Aril hue angle, all measured parameters had significant interaction effect regardless of locality (P<0.05). Total soluble solids content varied from 16.0–17.3 (°Brix), pH values from 2.7–3.0, titratable acid content varied from 1.3–1.7 and maturity index from 9.7–13.4. The anthocyanin, total phenols and antioxidant were in order of 772–1134; 1611–1834 and 12.57–14.84. Organic acids (Citric and Malic) showed differences while Acetic acid was not significant in all areas and organic sugar (fructose, Glucose and Sucrose) all had significant differences. It can also be concluded that changes in colour of peel and arils of pomegranate (cv. Wonderful) was mostly as a result of seasonal variation as well as growing area as evident by the interaction between both main factors. / Agriculture / M.Sc (Agriculture)
60

Nematode soil community structure and function as a bio-indicator of soil health in fynbos and deciduous fruit orchards

Kapp, Caro 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Soil is a fundamental, non-renewable resource in any ecosystem. To uphold food production for increasing global human populations, it is imperative to develop ways in which to sustain healthy biological productivity and sustainability of agricultural soils. Nematodes are one of the most abundant groups of Metazoa occurring in all soils, and form an integral part of the soil food web at several trophic levels. They respond rapidly to changes within their environments, and can easily be extracted from soil, identified and characterised into functional guilds. Nematodes thus have the potential to impart insight into the condition of the soil food web. This study aims to establish whether nematodes will be suitable bio-indicators of soil health for the deciduous fruit industry in the Western Cape. Three different objectives have been set to determine the practical use of nematode community structures as a tool for the measurement of soil health. The objectives include describing the nematode community structure, biodiversity and functionality within Fynbos soils; the characterization of organic and conventional orchards; and the differences in nematode soil communities in differently managed soils in an apple orchard. The number of nematodes in each soil sample was quantified and identified to family level. The nematode biodiversity and functionality for each site was determined by evaluating the nematode food webs for trophic group distribution, as enumerated by the Maturity Index (MI), the Enrichment Index (EI), the Structure Index (SI), the Basal Index (BI) and the Channel Index (CI), based on the weighted abundance of coloniser-persister guilds. The functional guild analysis of Fynbos samples indicated that the enrichment and the structure of any given sample were not bound to a certain area, but it was representative of each of the four quadrats within the faunal analysis. Different geographic areas were found to differ in nematode diversity and functionality, which was mainly associated with dominant plant families and species (such as strong associations between Fynbos families Fabaceae, Solanaceae and Celestraceae with the nematode family Pratylenchidae). The most abundant nematode families present in the Fynbos were Tylenchidae, which are plant-feeding nematodes, and Cephalobidae which are bacterial-feeding nematodes. Despite Tylenchidae and Cephalobidae both having coloniser-persister values (cp-values) of two, they are split up into different feeding types. Cp-2 nematodes are tolerant to disturbances, and occur in all environments. Only one omnivorous family, the Dorylaimida, was identified in Fynbos samples. The average MI value for Fynbos was found to be very low, with a mean value of 1.26. The value obtained indicated the presence of taxa with tolerance to disturbance, which, in turn, indicated the presence of a disturbed soil, in general. The number of plant-parasitic nematodes within the Fynbos soils was low, which was supported by the low plant-parasitic index (PPI) of 0.85. The diversity, richness and evenness values were low, indicating low nematode diversity, but a distribution of abundances amongst the families. The average Hill’s N0 index value was 8.0, indicating that, in general, eight nematode families would have been present in a Fynbos soil sample. A study was done to determine the biodiversity and the functionality of the nematodes associated with deciduous fruit orchards that were conventionally, or organically, managed. Herbivores were dominant in all the orchards. The organic apple orchard had the lowest numbers of herbivores and fungivores, with the highest number of carnivores. When comparing organic and conventional apricot orchards, higher numbers of plant-parasitic nematodes were found in the organic orchard. Criconematidae occurred in higher numbers in conventional apricot orchard soil. When comparing organic apricots and apples, higher numbers of Criconematidae occurred within the organic apple soil. Overall, higher levels of plant-parasitic nematodes occurred in the organic apricot orchard. The MI indicated that all orchard soils had values below 1.5, indicating disturbance. Conventionally managed apricot orchard soil had the highest MI value of 1.48. The PPI value was highest in organically managed apricot orchards. All orchard soils were located within Quadrat B of the faunal analysis, indicating enrichment and structure. Regarding the diversity, richness and evenness of the distribution, conventional apricot soil had the highest species richness, while organic apple soil had the most even family distribution. Different management practices did not show marked differences in community composition and structure. The species richness of Fynbos soils was comparable to those of deciduous fruit orchards. Soil samples from eight different soil surface treatments were collected from an apple orchard in the Grabouw area. Treatments were combined according to the soil surface treatments received (chemical control of cover crops and weeds, mulch and mulch + effective micro-organism spray). Bacterivores were dominant in all soil treatments, with the least number being present in the chemical control (of cover crops and weeds) treatment. Sites which received chemical control of cover crops and weeds had higher levels of fungivores, compared to the levels at the other sites. High numbers of Rhabditidae occurred within mulch and mulch + effective micro-organism (EM) treatment sites, while high numbers of Aphelenchidae occurred in chemical control sites. The carnivorous family Ironidae only occurred in mulch + EM sites. Strong associations were found between soil surface applications and nematode families present within the soil. Chemical control (of cover crops and weeds) applications had the highest MI value, while values were equal for the other soil applications. The faunal analysis indicated that the mulch and the chemical control fell within Quadrat A, indicating enriched, but unstructured, soil, while the mulch + EM treatment fell within Quadrat B, indicating enrichment and structure, as well as good overall soil conditions. All the systems were dominated by bacterial decomposition pathways. Controversially, sites that received chemical control of the cover crops and weeds had the highest species richness of all three applications, as well as the highest level of diversity, according to the Simpson Index. As only the cover crops and the weeds were chemically controlled, the soil can be regarded as undisturbed, which explains the results obtained in this study. Clear differences in nematode community structure and composition were observed between the different soil applications in the apple orchard. / AFRIKAANSE OPSOMMING: Grond is 'n fundamentele, nie-hernubare hulpbron binne enige ekosisteem. Ten einde voedselproduksie vir die toenemende globale menslike bevolking te handhaaf, is dit noodsaaklik om maniere te ontwikkel om gesonde biologiese produktiwiteit en volhoubaarheid van landbougrond in stand te hou. Nematodes is een van die volopste Metazoa in alle gronde en vorm 'n integrale deel van die grond voedsel-web op verskeie trofiese vlakke. Hulle reageer vinnig op veranderinge binne hul omgewings, kan maklik ekstraheer en identifiseer word; en ook maklik in funksionele gildes ingedeel word. Nematodes het ook die potensiaal om insig oor te dra ten opsigte van die toestand van die grond voedsel-web. Hierdie studie het ten doel om vas te stel of nematodes geskikte bio-indikatore van grond gesondheid kan wees spesifiek vir die sagtevrugte bedryf in die Wes-Kaap. Drie verskillende doelwitte is gestel om die praktiese gebruik van nematode populasie samestelling as 'n instrument vir die meting van grond gesondheid te gebruik. Die doelwitte sluit in die nematode populasie samestelling, biodiversiteit en funksionaliteit binne natuurlike Fynbos; organies verboude versus konvensionele boorde; en die verskil in nematode populasie samestelling tussen verskillend behandelde en bestuurde grondpersele binne ʼn appel boord. Die nematode biodiversiteit en funksionaliteit vir elke perseel was bepaal deur die evaluering van die nematode voedselweb vir trofiese groep verspreiding en enumerering deur die Maturity Index (MI) en die Enrichment Index (EI), Strukturele Indeks (SI), Basale Indeks (BI) en Channel Index (CI) wat gebaseer is op die geweegde oorvloed van koloniseerder-persister gildes. Die funksionele gilde vir Fynbos monsters het aangedui dat die verryking en struktuur van enige gegewe perseel nie gebonde is aan ʼn bepaalde gebied nie, aangesien dit verteenwoordig was in elk van die vier kwadrante van die Fauna Analiseerder. Daar is gevind dat verskillende areas verskil in nematode diversiteit en funksionaliteit, wat hoofsaaklik geassosieer was met die dominante plant families en spesies in die omgewing. Die volopste nematode familie wat teenwoordig was in die Fynbos was Tylenchidae, wat plant-voedende nematodes is, en Cephalobidae, wat bakterie-voedend is. Tylenchidae en Cephalobidae het beide ʼn cp-waarde van twee, maar is verdeel in verskillende VIII tipes voedingsgroepe. Die cp-2 nematodes is verdraagsaam vir versteurings en kom in alle omgewings voor. Slegs een omnivoor familie is geïdentifiseer in Fynbos monsters, nl. die Dorylaimidae. Die gemiddelde MI waarde vir Fynbos was laag, met 'n gemiddelde waarde van 1.26. Hierdie waarde is ʼn aanduiding van die teenwoordigheid van taxa met verdraagsaamheid tot versteuring, wat op sy beurt 'n versteurde grond in die algemeen aangedui het. Die aantal plant-parasitiese nematodes binne die Fynbos-gronde was laag, wat ondersteun word deur die lae PPI-waarde van 0.85. Die waardes vir die diversiteit, spesie-rykheid en egaligheid was laag, wat dui op 'n lae nematode diversiteit, maar 'n egalige verspreidings onder families. Die Hill’s N0 indeks waarde was gelyk aan 'n gemiddelde van 8.0 en dui daarop dat in die algemeen agt nematode families teenwoordig sal wees in 'n Fynbos grondmonster. 'n Studie is gedoen om die biodiversiteit en funksionaliteit van nematodes wat verband hou met vrugteboorde wat organies en konvensioneel bestuur is te bepaal. Herbivore was dominant in alle boorde. Organiese appels het die laagste aantal herbivore en fungivore gehad en die hoogste aantal karnivore. Wanneer organiese en konvensionele appelkoosboorde met mekaar vergelyk is, was hoër getalle van plant-parasitiese nematodes gevind in die organiese boord. Criconematidae was teen ʼn groter aantal in die grond van die konvensionele appelkoosboord gevind. Met die vergelyking van organiese appelkose en appels word, is ʼn hoër aantal Criconematidae binne die organiese appelgrond aangetref. In die algemeen was hoër vlakke van plant-parasitiese nematodes gevind in die organiese appelkoosboord. Die MI het getoon dat alle boord waardes laer as 1.5 gehad het, wat daarop dui dat die gronde versteurd is. Die konvensioneel bestuurde appelkoosboord het die hoogste MI waarde gehad met ʼn vlak van 1.48. Die waarde vir die PPI was die hoogste in organies bestuurde appelkoosboorde. Alle boord gronde is geleë binne kwadrant B van die Fauna Analiseerder, wat dui op verryking met struktuur. Met betrekking tot die diversiteit, spesie-rykheid en egaligheid van die verspreiding van families, het konvensionele appelkoos grond die hoogste spesierykheid, terwyl die gronde van die organiese appelboord die mees egalige familie verspreiding vertoon het. Verskillende bestuurspraktyke nie toon nie merkbare verskille in die gemeenskap samestelling en struktuur nie. Die spesie-rykheid van Fynbos gronde is vergelykbaar met dié van sagtevrugte-boorde. Monsters is geneem van agt verskillende grondeoppervlak-behandelings in ‘n appelboord in die Grabouw area. Die behandelings is gekombineer volgens die grond toediening wat dit ontvang het (chemiese beheer van dekgewasse en onkruid, deklaag en ‘n deklaag + effektiewe mikro- IX organismes). Bakterievoedende nematodes was dominant in elke grondoppervlak-behandeling, met die minste teenwoordig in die behandelings wat chemiese beheer van die dekgewasse en onkruid ontvang het. Behandelings wat chemiese beheer van die dekgewasse en onkruid ontvang het, het ook hoër vlakke van fungivore in vergelyking met die ander behandelings. ʼn Hoë aantal Rhabditidae het voorgekom in grondmonsters van die deklaag en die deklaag + EM (effektiewe mikro-organismes) behandeling persele, terwyl ʼn groot aantal Aphelenchidae voorgekom het in chemiese beheer persele. Die predatoriese familie, Ironidae, het slegs voorgekom in persele wat die deklaag + EM behandeling ontvang het. Sterk assosiasies bestaan tussen grond behandeling en nematode families wat in die grond teenwoordig was. Die chemiese beheer behandeling het die hoogste MI waarde getoon, terwyl waardes vir die ander behandelings laer en gelyk was. Die fauna analise het daarop gedui dat die deklaag en chemiese beheer binne kwadrant A is en dus verryk, maar ook ongestruktureerd is. Die deklaag + EM behandeling het binne kwadrant B geval wat aandui op toestande van verryking en struktuur wat 'n goeie algehele grondtoestand tot gevolg gehad het. Al die stelsels is oorbruggingsweë wat oorheers was deur bakteriële ontbinding. Kontroversieel, het persele wat chemiese beheer van die dekgewasse en onkruid ontvang het, die hoogste spesierykheid van al drie behandelings getoon asook die hoogste vlak van diversiteit volgens die Simpson-indeks. Slegs die dekgewasse en onkruid is chemies behandel, nie die grond nie, en dus kan die grond as onversteurd beskou word en die resultate wat verkry is in die studie verklaar. Duidelike verskille in die nematode gemeenskap struktuur en samestelling is waargeneem tussen die verskillende grond behandelings in appel boorde.

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