Orientador: José Carlos Barbosa / Coorientador: Marcílio Vieira Martins Filho / Banca: Carlos Alberto Alves de Oliveira / Banca: Carlos Antonio Alvarenga Gonçalves / Banca: Antonio Baldo Geraldo Martins / Banca: Luiz Carlos Pavani / Resumo: O presente trabalho teve como objetivo analisar a variabilidade espacial de atributos químicos de Latossolo Vermelho distrófico, caracterizar genótipos de uvaieira, quanto à similaridade e analisar a sua relação com a variabilidade dos atributos químicos do solo. Para isso levou-se em conta as poucas informações existentes sobre a uvaieira, o potencial de exploração agroindustrial que esta fruteira apresenta e a necessidade de se preservar o ainda pouco conhecido patrimônio genético, A uvaieira é uma planta silvestre, espécie perene, nativa da Mata Atlântica, encontrada nos estados de São Paulo, Paraná, Santa Catarina, Rio Grande do Sul. Frutífera da família Myrtaceae, de nome científico Eugenia pyriformis Cambess, popularmente denominada uvaia, uvalha, uvaia-do-mato, uvaieira ou uvalha-do-campo. O experimento foi conduzido no ano de 2010, no Instituto Federal de Educação, Ciência e Tecnologia do Triangulo Mineiro (IFTM), Câmpus de Uberaba - MG, em área delimitada pelos paralelos 19º 39' 16,46" e 19º 39' 20,80" de latitude sul e longitude de 47º 57' 28,67'' e 47º 57' 35,55'' a oeste de Greenwich, com altitude média de 825 m. Foram coletadas amostras de solo, nas camadas de 0,0-0,2 m, de 0,2-0,4 m e de 0,4-0,6 m, em malha de 127 pontos georreferenciados. Determinado o pH (em CaCl2), P e K+ disponíveis, Ca2+, Mg2+, H+Al e MO e calculou-se a capacidade de troca de cátions e soma de bases. Obteve-se os dados de produção, diâmetro (largura) de copa, perímetro do caule e massa média do fruto de 182 plantas de uvaieira. Utilizando os métodos da estatística tradicional, a técnica do georreferenciamento e os recursos da geoestatística, analisou-se a variabilidade de atributos químicos do solo, as características agronômicas de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The goal of this present study was to analyze the spatial variability of chemical properties of Oxisol, characterize genotypes of "uvaieira", as to similarity and analyze its relationship to the variability of soil chemical properties. The few studies about the "uvaieira", the exploration of the potential of agribusiness that this fruit presents and the need to preserve the still little-known genetic heritage. The "uvaieira" is a wild plant, perennial species, native to the Atlantic Forest, found in the states of São Paulo, Paraná, Santa Catarina and Rio Grande do Sul. Fruitful, tree from the Myrtaceae family, scientific name Eugenia pyriformis Cambess, popularly called uvaia, uvalha, wild uvaia, or uvaieira or wild uvalha. The experiment was conducted in 2010, at the Federal Institute of Education, Science and Technology of Triângulo Mineiro (IFTM), Campus of Uberaba - MG, in area bounded by the parallels 19 º 39 '16.46 "and 19 º 39' 20.80" South latitude and longitude of 47 ° 57 '28.67'' and 47 º 57' 35.55'' west of Greenwich, with an average altitude of 825 m. Soil samples were collected from layers of 0.0-0.2 m, 0.2-0.4 m and of 0.4-0.6 m, mesh of 127 georeferenced points. It was determined the pH (CaCl2), available P and K +, Ca2 +, Mg2 +, H + Al and OM, and calculated the cation exchange capacity and sum of bases. It was obtained production data, diameter (width) of canopy, stem girth and fruit weight of 182 uvaieira plants. Using traditional statistical methods, the technique of georeferencing and geostatistics resources, it was analyzed the variability of soil chemical properties, agronomic traits of interest in "uvaieiras" genotypes, and evaluated... (Complete abstract click electronic access below) / Doutor

Malgré son importance économique, culturelle et historique, l’histoire évolutive du pommier cultivé (Malus domestica) ainsi que celle de ses apparentés sauvages supposés, restaient encore très peu connues. En s’appuyant sur les nouvelles approches de génétique des populations (approximate Bayesian computation) avec l’utilisation de marqueurs microsatellites et de séquences nucléaires, cette thèse a eu pour objectif d’étudier, à différentes échelles évolutives (phylogéographie, spéciation, domestication), les mécanismes de diversification naturelle et artificielle dans le genre Malus. Mes travaux ont porté sur quatre espèces de pommiers sauvages distribuées à travers l’Eurasie (Malus orientalis (Caucase), Malus sieversii (Asie Centrale), Malus sylvestris (Europe), et Malus baccata (Sibérie)) et sur la seule espèce domestiquée du genre, Malus domestica. Cette thèse s’est articulée en quatre parties visant respectivement à inférer : (i) l’histoire de la domestication du pommier cultivé depuis son centre d’origine en Asie Centrale, (ii) l’histoire de la recolonisation post-glaciaire du pommier sauvage Européen (M. sylvestris), (iii) les histoires de spéciation entre les cinq espèces de Malus, (iv) les hybridations interspécifiques et les capacités de dispersion des trois principaux contributeurs (M. sylvestris, M. sieversii et M. orientalis) au génome du pommier cultivé. L’étude des mécanismes de diversification artificielle montre que les processus de domestication sont originaux chez cet arbre fruitier, de par l'absence de goulet d’étranglement et l’existence d’introgressions post-domestication fréquentes par une autre espèce sauvage (M. sylvestris) que l’espèce ancestrale (M. sieversii). L’étude des processus de diversification naturelle (phylogéographie, spéciation et structure des populations) révèlent de grandes tailles de populations, de forts flux de gènes et de faibles structures génétiques spatiales chez chacune des espèces. Cette thèse a aussi révélé de forts taux d’hybridations interspécifiques, en particulier de fortes introgressions des espèces de pommiers sauvages par le pommier cultivé en Europe et en Asie Centrale. Cette étude a permis l'amélioration des connaissances de la structuration des populations de pommiers sauvages ayant contribué au génome du pommier cultivé ainsi que de l’étendue des hybridations du pommier cultivé avec les espèces sauvages. Ces travaux revêtent une grande importance autant pour la conservation des pommiers sauvages, pour le maintien de leur intégrité dans des habitats fragmentés que pour l'amélioration variétale du pommier domestiqué. / : Despite its economic, cultural and historical importance, few studies have investigated the evolutionary history of the domesticated apple (Malus domestica) as well as those of its wild relatives. Using new population genetic approaches (approximate Bayesian computation) with microsatellites and nuclear sequences, this thesis aimed at unravelling, at different evolutionary scales (phylogeography, speciation, domestication), the natural and artificial diversification processes at play in the Malus genus. My research focused on the four wild apple species distributed across Eurasia (Malus orientalis (Caucasus), Malus sieversii (Central Asia), Malus sylvestris (Europe), and Malus baccata (Siberia)) and on the single domesticated apple species in the genus, Malus domestica. This thesis was divided into four parts: (i) domestication history of the cultivated apple, from its origin in Central Asia to Europe, (ii) post-glacial recolonization history of the European crabapple (M. sylvestris), (iii) the history of speciation among the five Malus species, (iv) crop-to-wild gene flow and dispersal capacities of the closest wild relative species (M. sylvestris, M. sieversii and M. orientalis). By investigating artificial diversification, we evidenced unique processes of domestication in this fruit tree, with no bottleneck and with extensive post-domestication introgressions by another wild species (M. sylvestris) than the ancestral progenitor (M. sieversii). Natural diversification patterns (phylogeography, speciation and population structure) revealed large effective population sizes, high dispersal capacities and weak spatial genetic structures. This thesis also revealed high levels of interspecific hybridizations, particularly high level of crop-to-wild gene flow in Europe and Central Asia. This study extended our knowledge about population structures for wild species that contributed to the cultivated apple genome, as well as the extent of hybridization rates. This work is essential for the conservation of wild apple populations, the integrity maintenance of wild species facing fragmentation and future breeding programs concerning the domesticated apple.

Made available in DSpace on 2014-06-11T19:31:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-18Bitstream added on 2014-06-13T21:01:59Z : No. of bitstreams: 1 silva_wp_dr_jabo.pdf: 2012302 bytes, checksum: 99ecaf67a66dc85233a13c4a2ac52d48 (MD5) / O presente trabalho teve como objetivo analisar a variabilidade espacial de atributos químicos de Latossolo Vermelho distrófico, caracterizar genótipos de uvaieira, quanto à similaridade e analisar a sua relação com a variabilidade dos atributos químicos do solo. Para isso levou-se em conta as poucas informações existentes sobre a uvaieira, o potencial de exploração agroindustrial que esta fruteira apresenta e a necessidade de se preservar o ainda pouco conhecido patrimônio genético, A uvaieira é uma planta silvestre, espécie perene, nativa da Mata Atlântica, encontrada nos estados de São Paulo, Paraná, Santa Catarina, Rio Grande do Sul. Frutífera da família Myrtaceae, de nome científico Eugenia pyriformis Cambess, popularmente denominada uvaia, uvalha, uvaia-do-mato, uvaieira ou uvalha-do-campo. O experimento foi conduzido no ano de 2010, no Instituto Federal de Educação, Ciência e Tecnologia do Triangulo Mineiro (IFTM), Câmpus de Uberaba - MG, em área delimitada pelos paralelos 19º 39’ 16,46” e 19º 39’ 20,80” de latitude sul e longitude de 47º 57’ 28,67’’ e 47º 57’ 35,55’’ a oeste de Greenwich, com altitude média de 825 m. Foram coletadas amostras de solo, nas camadas de 0,0-0,2 m, de 0,2-0,4 m e de 0,4-0,6 m, em malha de 127 pontos georreferenciados. Determinado o pH (em CaCl2), P e K+ disponíveis, Ca2+, Mg2+, H+Al e MO e calculou-se a capacidade de troca de cátions e soma de bases. Obteve-se os dados de produção, diâmetro (largura) de copa, perímetro do caule e massa média do fruto de 182 plantas de uvaieira. Utilizando os métodos da estatística tradicional, a técnica do georreferenciamento e os recursos da geoestatística, analisou-se a variabilidade de atributos químicos do solo, as características agronômicas de... / The goal of this present study was to analyze the spatial variability of chemical properties of Oxisol, characterize genotypes of “uvaieira”, as to similarity and analyze its relationship to the variability of soil chemical properties. The few studies about the “uvaieira”, the exploration of the potential of agribusiness that this fruit presents and the need to preserve the still little-known genetic heritage. The “uvaieira” is a wild plant, perennial species, native to the Atlantic Forest, found in the states of São Paulo, Paraná, Santa Catarina and Rio Grande do Sul. Fruitful, tree from the Myrtaceae family, scientific name Eugenia pyriformis Cambess, popularly called uvaia, uvalha, wild uvaia, or uvaieira or wild uvalha. The experiment was conducted in 2010, at the Federal Institute of Education, Science and Technology of Triângulo Mineiro (IFTM), Campus of Uberaba - MG, in area bounded by the parallels 19 º 39 '16.46 and 19 º 39' 20.80 South latitude and longitude of 47 ° 57 '28.67'' and 47 º 57' 35.55'' west of Greenwich, with an average altitude of 825 m. Soil samples were collected from layers of 0.0-0.2 m, 0.2-0.4 m and of 0.4-0.6 m, mesh of 127 georeferenced points. It was determined the pH (CaCl2), available P and K +, Ca2 +, Mg2 +, H + Al and OM, and calculated the cation exchange capacity and sum of bases. It was obtained production data, diameter (width) of canopy, stem girth and fruit weight of 182 uvaieira plants. Using traditional statistical methods, the technique of georeferencing and geostatistics resources, it was analyzed the variability of soil chemical properties, agronomic traits of interest in “uvaieiras” genotypes, and evaluated... (Complete abstract click electronic access below)

Thesis (M. Agric. (Plant Production)) -- University of Limpopo, 2018 / The evergreen Red Milkwood (Mimusops zeyheri Sond.) is being targeted as a rural and urban-greening tree in Limpopo Province, due to its excellent nutritional, pharmaceutical and aesthetic attributes. Slow growth of M. zeyheri seedlings is the main drawback in the potential domestication and commercialisation of this tree species. The objectives of this study were to determine (1) the influence of soil type on root growth and foliar nutrient elements in M. zeyheri seedlings, (2) the degree of salt tolerance in M. zeyheri seedlings and (3) the influence of vesicular arbuscular mycorrhiza (VAM) fungi on growth of M. zeyheri seedlings. Objective 1 was achieved in clay, calcareous, loam and sandy soils. At 60 days after the treatments, soil type effects were significant on plant height, leaf number, chlorophyll content of primary leaves (dicots), chlorophyll content of secondary leaves, root length, number of root branches and dry root mass, contributing 60, 72, 84, 85, 74, 80 and 40% in total treatment variation (TTV) of the respective variables. Objective 2 was achieved by exposing seedlings to 0, 2, 4, 8, 16, 32, 64 and 128 NaCl + CaCl2 mM/m3 at 3:1 ratio. At 90 days after the treatments, salinity effects were significant on leaf number, dry shoot mass, root length and leaf length, contributing 73, 60, 50 and 64% in TTV of the respective variables. Leaf number, dry shoot mass, root length and leaf length each against increasing concentration of salinity exhibited positive curvilinear quadratic relations, with 74, 91, 95 and 66% associations, respectively. Responses of essential nutrient accumulation in leaf tissues of M. zeyheri to salt treatments had significant effects on K and Na, contributing 28 and 19% in TTV of the respective variables. Potassium over increasing salt concentrations exhibited positive quadratic relations and Na over increasing salt concentrations, exhibited negative quadratic relations. The models for each relation were explained by 95 and 86%, respectively. Objective 3 was achieved by exposing seedlings to 0, 10, 20, 30, 40, 50, 60 and 70 g VAM per plant. At 90 days after the treatments, VAM effects were significant on plant height, leaf number, stem diameter and chlorophyll content contributing, 49, 65, 60 and 61% in TTV of the respective variables. Plant height, leaf number and chlorophyll content each against increasing VAM levels exhibited negative quadratic relations, with 97, 83 and 80% associates, respectively. In conclusion, the use of soil type to promote growth and accumulation of essential nutrient elements on M. zeyheri seedlings demonstrated that clay soil could be suitable for cultivation of M. zeyheri. Also chloride salt concentrations included all three phases of density-dependent growth (DDG) patterns, whereas VAM levels used in the study were already in the last two phases of DDG patterns. Vesicular arbuscular mycorrhiza treatment did not have significant effects on Ca, Fe, K, Na and Zn in leaf tissues of M. zeyheri seedlings. In conclusion, soil with high clay content could be ideal when raising M. zeyheri seedlings. However, salt concentration of 8.11 mM/m3 exhibited the stimulation of M. zeyheri seedlings growth, Therefore, lower concentration less than 8.11 mM/m3 shown to be toxic by reducing the plant growth. In contrast, 5.554 g per plant of VAM will supreme for growth and development of M. zeyheri seedlings.

An alternative to herbicides in dwarf apple orchards (Malus pumila Mill.) is the use of mulches. Research objectives were to compare several mulch systems (Festuca rubra L., Lupinus albus L. plus Daucus carota L.; straw, manure compost, geotextile) with soil cultivation as to soil physical properties and plant nutrient levels in soils, leaves and fruit. Studies carried out in 1992 and 1993 on three dwarf apple orchards on the Macdonald Campus of McGill University showed that straw mulch increased soil water contents and exchangeable K, but reduced exchangeable Mg compared to Festuca mulch. Straw mulch reduced soil temperatures in summer relative to geotextile or cultivation. Festuca reduced leaf N contents but increased leaf P contents-elative to geotextile treatments. Soil nitrate N contents were correlated with soil water contents, and the ratios N/Ca and K/Ca in the fruit were unaffected by treatment. Straw and geotextile mulches increased soil water content and nitrate-N levels during peak sowing periods and thus were the superior treatments.

Propagating methods for peach (Prumis persica L. Batsch.) are currently limited to the use of seeds or cuttings. Most of the rootstocks commonly used for establishing peach trees commercially originate from a narrow genetic base. The most commonly used peach rootstock in South Africa is 'Kakamas', which has disadvantages such as slow growth, and a high susceptibility to certain pests and diseases. 'Kakamas' is classified as a mid to late ripening cultivar, hence, its use as a rootstock is restricted in early ripening cultivars. Optimising peach seedling and cutting production may on the other hand increase more selection material that will increase genetic variability and also serve as the basis for future production and selection of rootstocks for peach nursery establishments. Hence, this study was designed to improves success of peach cutting production by increasing the rooting percentage and the survival rate of cuttings. This was firstly achieved by the application of various concentrations of IBA and several rooting-cofactors. Secondly, rooting success of cuttings taken at different seasons was studied. The response of two cutting positions to various IBA and rooting-cofactor was evaluated. Attempts were also made to overcome the requirement of peaches for a seed stratification period by using plant growth regulators. Studies to optimise the establishment and growth of embryos of early to late ripening cultivars ('Klara', 'Oom Sarel' and' Summer Giant') in vitro were undertaken to overcome the problem of small underdeveloped embryos which are often obtained from early ripening peach cultivars. The early ripening peach cultivars 'DeWet', 'Earlibelle' and 'Florida Prince' were propagated by softwood, semi-hardwood and hardwood cuttings prepared from August 1999 to July 2000. It was found that softwood cuttings prepared in October and November responded well to an IBA application of 1000 mg 1(-1), resulting in 100 % rooting in all three cultivars. In 'Florida Prince' and 'DeWet' the rooting-cofactors chlorogenic acid and phloroglucinol at the concentration of 100ug 1(-1) yielded 77 % and 81 % rooting, respectively while quercitin and rutinin gave only 46 and 44 % rooting for all cultivars. The basal portion of the cutting rooted better than the terminal portion (78 % versus 58 %). Rooting percentage differed in all treatments in response to IBA application and rooting-cofactors 74 % for 'Florida Prince', 62 % for 'DeWet' and 54 % for 'Earlibelle'. The use of IBA and Ca-EDTA proved to be beneficial for rooting of 'Florida Prince' cuttings and resulted in a rooting percentage of 86 % in wounded hardwood cuttings of this cultivar. It was also shown that the simple sugars glucose, fructose and sucrose as well as the sugar alcohols sorbitol and mannitol accumulated at the base of the cutting during adventitious base root formation if the cutting bases were treated with 1000 mg 1(-1) IBA. The concentration of these sugars and sugar alcohols were lower in untreated cuttings compared to IBA treated cuttings during the adventitious root formation process. Studies on the origin of adventitious root formation in stem cuttings of peaches were conducted using light microscopy and transmission electron microscopy. These studies revealed that adventitious roots originate (in peaches) in the vicinity of the vascular bundle tissue and in the cells around them. It was found, however, that adventitious root formation in IBA treated cuttings is associated with the formation of root primordia. These may trigger root initiation and ultimately the development of adventitious roots. In embryo culture studies the highest number of roots and greatest length of roots per embryo as well as the highest number of embryos forming roots was achieved when either the medium of Murashige and Skoog (MS) (1962) or of Steward and Hsu (SH) (1978) were employed. The Woody Plant medium (Lloyd and McCowan, 1978) and the medium after Schenk and Hildebrandt (1972) were found to be less effective when compared to MS and SH media. Addition of GA(3) (0.01 mg 1(-1)), BAP (0.2 mg 1(-1)) or GA(3) (0.01 mg 1(-1))+ BAP (0.2 mg 1(-1))+IBA (0.5 mg 1(-1)) to the media gave the best results with respect to embryos forming roots (86 %), number of roots per embryo (8.0) and total length of roots per embryo (7.57 cm). Furthermore, the following conditions for optimal rooting of peach embryos were established: pH 5.2, 1.5 g 1(-1) agar, 60 g 1(-1) sucrose and 16h light/8h darkness photo period. Further studies on the influence of the stratification temperature on germination of embryos revealed the highest germination percentage after exposure to 40 C ±2 constantly for 30 to 60 days. However, this chilling requirement can be successfully substituted by the addition of GA(3) , kinetin, zeatin, BA and thiourea to the culture media. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.

Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Three field trials were conducted to investigate the effects of mulching on the chemical and biological aspects of the soil as it is reflected by tree performance and fruit quality in ‘Cripps’ Pink’ orchards. In the two trials at Lourensford Estate, where only the soil type differed between sandy silt loam (sandy) and heavy silt loam (heavy), mulches where used as an additive to the soil surface together with a standard, commercial, inorganic fertilization program. Four different mulch types: compost, wood chips, vermi-compost and a geotextile fabric, were compared to a bare surface control in a randomized complete block design. At the heavy silt loam site (site 1), the wood chips treatment was the most effective in regulating diurnal soil temperatures in the top 10 cm of soil (2009/10), whereas all mulches regulated average diurnal soil temperature similarly and more effectively than the control at the sandy silt loam site (site 2). After two seasons of treatment at site 1, the vermi-compost treatment significantly increased soil phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), manganese (Mn), zink (Zn) and boron (B) significantly compared to the control. The wood chips treatment increased Na, K and Ca and compost only increased soil K significantly compared to the control. For site 2, only wood chips (Na and K) and vermi-compost (Na, K and Mg) showed significant increases in soil nutrient elements compared to the control. Yield efficiency was significantly increased by the wood chips (both seasons) and vermicompost (only 2009/10) treatments compared to the control in site 1. In site 2, none of the treatments differed significantly in yield efficiency compared to the control treatment. The number of roots and fine feeder roots were increased (not sign) by the wood chips and geotextile treatments compared to the control. In site 1, all treatments improved the number of roots compared to the control treatment, in contrast with site 2, where the number of roots of the control, compost and vermi-compost treatments was more similar. Fruit quality showed significant differences between the wood chips and vermi-compost treatments compared to the geotextile and control treatments for malic acid, at site 1, at harvest in 2009. This did not differ significantly from the compost treatment. Leaf mineral analysis only showed significant differences at site 2, in 2010, with significantly increased for the following minerals and treatments: Mn (compost and geotextile treatments versus other treatments), Fe (control treatment compared to all treatments except compost), Zn (compost compared to all other treatments) and B (control and compost versus vermicompost, wood chips and geotextile). Fruit mineral analyses showed no differences between treatments at harvest 2009 for either site and 2010, for site 1. At site 2, the Ca percentage of fruit from the wood chips treatment was significantly higher than that of all treatments, except the geotextile treatment. Only in the 2010 analysis at site 2, the mycorrhizal colonization was significantly influenced, where all the mulching treatments showed an increase compared to the control. However, the same trend was observed at site 1. At site 1and 2, the compost, wood chips and vermi-compost treatments in general showed a decreasing trend in percentage plant parasitic and increasing trend in percentage free living nematodes from 2009 to 2010. In general, the geotextile and control treatments showed an increasing trend in the percentage plant parasitic and decrease in percentage free living nematodes. However, this was not the case at 0 – 15 cm soil depth for site 1. In the third trial, at Elgin Experimental Farm (Elgin), bare surface chemical control was compared to mulching in the tree row (mulch) and mulching together with regular application of compost tea (mulch + compost tea). All treatments were combined with different inter row management practices to compose a total of eight different treatments. In the tree row, the control treatment received standard rates of inorganic fertilizer, which was compared to the mulched only treatment. Both the percentage of soil carbon and cation exchange capacity was significantly increased by all the mulch treatments compared to the control. Furthermore, all the mulches increased various soil minerals significantly, however of which only P was significantly increased in both the leaves and fruit. The rate of soil microbial activity and mycorrhizal root colonization was significantly increased by mulching treatments, but resulted in a significantly lower yield efficiency compared to the inorganic control treatment. This can be ascribed partly to the microbial activity of the compost mulch during spring, although it was not quantified per se and to the increase in tree vigour at the end of the trial. The slow rate of N mineralization was reflected indirectly by the significantly lower fruit N for the mulched treatments and the lower rate of microbial activity during spring at this site. With regards to the addition of the compost tea, no significant contributions were evident in terms of tree performance, soil minerals or microbial activity over a period of seven years, compared to the application of mulch only. Compared to the trial at Lourensford Estate, with no significant differences in fruit mineral composition between treatments after two years, fruit mineral analyses of the Elgin trial showed significant differences between treatments after six (2009) and seven (2010) seasons for P for some treatments. Only in 2010 more treatments showed significant differences for N, Mn, Fe and Zn as well. Regarding fruit quality, in agreement with the results at Lourensford Estate, differences were not persistent across all seasons for treatments. / AFRIKAANSE OPSOMMING: Veldproewe is geloods om die effek van verskillende deklae op grond chemiese en – biologiese aspekte en die effek daarvan op boom prestasie en vrugkwaliteit in ‘Cripps’ Pink’ appelboorde te ondersoek. In die eerste twee proewe te Lourensford Landgoed, waar slegs die grondtipe verskil het tussen die sanderige slik leem (ligter) en swaarder slik leem (swaar) gronde, is deklae toegedien saam met ‘n standard bemestingsprogram en mikro-besproeiingstelsel. Vier deklaagtipes: kompos, houtspaanders, vermi-kompos en geotekstiel material, is vergelyk met die onbedekte, skoon bewerkte, kontrole in ‘n total ewekansige blokontwerp. By die swaar grondtipe (perseel 1), was die houtspaanderbehandling die effektiefste om die daaglikse skommelings in grondtemperatuur te reguleer in die boonste 10 cm, teenoor die sanderige perseel (2), waar al die deklae die daaglikse grondtemperatuur meer effektief as die kontrole behandeling gereguleer het. By perseel 1, het die vermi-behandeling ‘n betekenisvolle toename getoon teenoor die kontrole behandeling in grond fosfaat (P), kalium (K), kalsium (Ca), magnesium (Mg), natriuim (Na), mangaan (Mn), sink (Zn) en boor (B). Alhoewel dit nog nie tans gekwantifiseer kan word nie, is ‘n gedeelte van die toename heel moontlik te wyte aan die samestelling van die deklaag. Die houtspaander- en komposbehandelings het ‘n betekenisvolle verskil in toename tot gevolg gehad in grond K en Na in vergelyking met die kontrole. In die geval kan die toename van die komposbehandeling aan die invloed van die sampestelling van die deklaag toegeskryf word, maar nie in die geval van die houtspaanderbehandeling nie. Die geotekstielbehandeling het, soos verwag, nie betekenisvolle verskille ten opsigte van die kontrole getoon nie, aangesien die samestelling van die geotekstielmateriaal nie voedingstowwe tot die grond kan toevoeg nie. By perseel 2, het beide die houtspaander- en geotekstielbehandelings betekenisvolle toenames in grond elemente (K, Mg) getoon teenoor die kontrole behandeling. Die ander elemente het nie noemenswaardige verskille teenoor die kontrole getoon nie. Weer eens kan die toename in die vermi-kompos toegeskryf word aan die samestelling van die deklaag, maar nie in geval van die houtspaanders nie, wat ‘n moontlike rol van ander faktore soos temperatuur en grondvog in die opname en beskikbaarheid van voedingselemente toon. Op 30 cm diepte in perseel 1, het die vermi-kompos behandeling betekenisvolle hoër Na, K, Mg en P getoon as die kontrole. Die houtspaanderbehandeling het betekenisvolle hoër Na, K en Ca getoon as die kontrole. Geen een van die ander behandelings het enige betekenisvolle veranderinge ten opsigte van voedingselemente getoon nie. Vir perseel 2 by die gronddiepte, het die houtspaanderbehandeling betekenisvolle toenames in grond Na en K getoon teenoor die kontrole. Geen van die ander behandelings het enige betekenisvolle veranderinge ten opsigte van voedingselemente getoon nie. By hierdie dieper gronddieptes is ‘n soortgelyke verandering in elemente waargeneem as by die vlakker gronddieptes vir perseel 1, in geval van P en K. Mg en Na het volgehoue verandering vir die vermi-komposbehandeling in die dieper gronddieptes getoon vir die makro-elemente, maar nog nie in geval van mikroelemente nie. In perseel 2 – het toenames in K en Mg in die vermi-komposbehandeling ook voortgeduur en die veranderinge vir beide persele mag toegeskryf word aan die samestelling van die deklae per se. Dit blyk dat die veranderinge in die komposbehandeling nie so konstant voorgekom het in die materiaal wat in die proewe toegedien is nie. Nietemin kan die kompos- en vermi-komposbehandelings ook ander grond faktore beïnvloed en die bydra van die minerale elemente afkomstig uit die samestelling van die deklaag moet eers bereken word alvorens afleidings gemaak word. By beide persele het die komposbehandeling die opbrengseffektiwiteit verminder in vergelyking met die kontrole behandeling. Die opbrengseffektiwiteit is betekenisvol verhoog in die houtspaanderbehandeling (beide seisoene) en vermi-komposbehandeling (net 2009/10) in vergelyking met die kontrole in perseel 1. In perseel 2 het teen behandeling betekenisvol in opbrengseffektiwiteit verskil ten opsigte van die kontrole nie. Die aantal wortels en fyn, voedingswortels het ‘n dramatiese (nie-betekenisvolle) toename getoon by die houtspaander- en geotekstielbehandelings. In perseel 1 het alle behandelings die aantal wortels verhoog ten opsigte van die kontrole in kontras met perseel 2, waar die aantal wortels in die kontrole, kompos- en vermi-komposbehandelings ongeveer dieselfde was. Stamwaterpotensiaal het onveranderd gebly ongeag van die behandeling, wat moontlik beïnvloed is deur die hoë besproeiingskedulering siklus. Geen verskille tussen behandelings of persele is gevind nie. Alhoewel dit net in die tweede seisoen (2010) gemeet is, was daar geen betekenisvolle verskille in gemiddelde loot groei van eenjaarlote tussen die behandelings of persele nie. Vrugkwaliteit het betekenisvolle verskille getoon in appelsuur (malic acid) in die houtspaander- en vermi-komposbehandelings teenooor die geotekstie- en kontrole behandelings in perseel 1, by oes 2009. Laasgenoemde het nie betekenisvol van die kontrol behandeling verskil nie. Hierdie verskille het nie na opberging voortgeduur nie. Geen betekenisvolle verskille in vrugkwaliteit het voorgekom by perseel 2, tydens oes, of na opberging nie. Gedurende oes 2010, asook na opberging, is geen verskille in vrugkwaliteite van enige persele opgemerk nie. Behandelingsverskille in blaar-analises is waargeneem tussen vermi-kompos- en die ander behandelings, met uitsondering van die geotekstielbehandeling in Februarie 2009, perseel 1. Geen ander betekenisvolle verskille vir enige element het voorgekom tussen behandelings in perseel 2 nie. Gedurende 2010 is geen betekenisvolle verskille tussen behandelings ten opsigte van blaar-analises gevind vir perseel 1 nie. Betekenisvolle verskille in blaar- en vrugmineraal-analises was in perseel 2 teenwoordig as volg: Mn (kompos- en geotekstielbehandelings teenoor al die ander behandelings), Fe (kontrolebehandeling teenoor alle ander behandelings behalwe die komposbehandeling), Zn (komposbehandeling teenoor al die ander behandelings) en B (kontrole en komposbehandelings teenoor vermi-, houtspaander- en geotekstielbehandelings (gedurende 2010. Die vrugmineraal-analises het geen verskille getoon tussen behandelings by oes 2009 vir enige perseel, of 2010 vir perseel, 1 nie. By perseel 2 was die Ca persentasie in die vrug in die houtspaanderbehandeling betekenisvol hoër as die van die ander behandelings, uitgesonder die geotekstielbehandeling. By perseel 1, het al die behandelings die persentasie mycorrhiza-kolonisasie verhoog in vergelyking met die kontrole, alhoewel dit nie betekenisvol was nie. By perseel 2 was daar wel ‘n betekenisvolle toename in die persentasie mycorrhiza-kolonisasie by al die deklaagbehandelings in vergelyking met skoonbewerking van die kontrole behandeling. Die persentasie plant-parasitiese nematodes was baie variëerend met gronddiepte by beide persele. Die houtspaander- en vermi-komposbehandelings in perseel 1 het ‘n afwaartse tendens getoon in die persentasie plant-parasitiese en toename in persentasie vry-lewende nematode vanaf 2009 na 2010, in die 0-15 cm diepte. In teenstelling, het die geotekstiel- en komposbehandeling ‘n toenemende tendens getoon in die persentasie plant-parasitiese en klein afname in persentasie vrylewende nematodes vanaf 2009 tot 2010. Geen betekenisvolle verskille in nematode getalle is waargeneem in gronddiepte 15 -30 cm grond in die perseel nie. In perseel 2 is geen betekenisvolle verskille in aantal nematodes gevind gedurende die twee seisoene tussen behandelings of binne persele op 0-15 cm gronddiepte nie. Nietemin het die houtspaander-, kompos- en vermi-komposbehandelings die persentasie plant-parasitiese verlaag en die van die vry-lewende nematode verhoog vanaf 2009 tot 2010, in vergelyking met die kontrole in die 15-30 cm gronddiepte. Slegs die houtspaanderbehandeling het betekenisvolle verskille getoon teenoor die kontrole. Die geotekstiel- het dieselfde tendens as die kontrole behandeling getoon, met ‘n toename in persentasie parasities- en afname in persentasie vry-lewende nematode. Die kontrole en geotekstielbehandelings het nie betekenisvol van mekaar verskil nie. Die aantal erdwurms en meso-fauna was baie laag tydens die eerste twee jaar by beide die persele en data is daarom nie statisties verwerk nie. By die derde proef, is ‘n skoonbewerkte oppervlak, wat chemiese beheer (kontrole) behels het, vergelyk met deklaagbehandelings in die boomry (deklaag) en behandelings waar kompostee saam met die deklaag toegedien was in die boomry (deklaag + kompostee). Al die behandelings is gekombineer met verkillende tussenry behandelings wat ‘n totaal van agt verskillende behandelings behels het. Hierdie verslag konsentreer slegs op die behandelings in die boomry, waar die kontrole behandelings wat ‘n standaard bememestings program ontvang het, vergelyk word met die deklaag behandelings, wat geen alternatiewe bemesting ontvang het nie en as organise alternatiewe beskou word in ‘n ‘Cripps’ Pink’ appelboord. Klem in die verslag is gelê op die hoof effekte van die behandelings op vrugkwaliteit. Beide die persentasie grondkoolstof en die katioonuitruilkapasiteit het ‘n betekenisvolle toename getoon by al die deklaagbehandelings in vergelyking met die kontrole behandeling. Terselfdetyd, het al die deklaagbehandelings ook verskeie grondminerale betekenisvol verhoog, waarvan slegs P betekenisvol in beide die blare en vrugte verhoog is. Die tempo van grondmikrobe aktiwiteit en micorrhiza-kolonisasie van die wortels is betekenisvol verhoog deur die deklaagbehandelings, maar het gerealiseer in ‘n betekenisvolle laer opbrengseffektiwiteit in vergelyking met die anorganiese, kontrole behandeling. Dit kan onder andere toegeskryf word aan die mikrobe aktiwiteit van die komposdeklaag gedurende die lente – alhoewel dit nie per se in die studie gekwantifiseer is nie, sook die toename in vegetatiewe groeikrag aan die einde van die proeftydperk. Dit is wel indirek gereflekteer deur die betekenisvolle, laer vrug N van die deklaagbehandelings en die laer tempo van mikrobe aktiwiteit gedurende die lente by die deklaagbehandelings op die perseel. Wat die toedienning van kompostee betref, het dit geen betekenisvolle bydra gelewer in terme van gewasprestasie, grondminerale of microbe-aktiwiteit oor ‘n tydperk van sewe jaar in vergelyking met die behandelings waar die deklaag geen kompostee ontvang het nie. In vergelyking met die proef by Lourensford Landgoed, met geen betekenisvolle verskille in vrug mineral-analises tussen die behandelings oor ‘n tydperk van twee jaar nie, het die proef te Elgin wel betekenisvolle verskille tussen behandelings na 6 (2009) en 7 (2010) jaar getoon in geval van P, vir sekere behandelings (4,7,8 versus 1,2,6). Slegs in 2010 het meer behandelings betekenisvolle verskille getoon vir N, Mn, Fe en Zn. Rakende vrugkwaliteit - in ooreenstemming met resultate van 2009 vir perseel 1 te Lourensford Landgoed - het beide seisoene betekenisvolle verskille ten opsigte van appelsuur getoon in Elgin. Die verskille het egter nie konstant in al die behandelings voorgekom nie. Stysel afbraak, totaal oplosbare stowwe en fermheid het ook betekenisvolle verskille tussen behandelings getoon in Elgin – maar dit was nie konsekwent oor behandelings of seisoene nie en het ook nie voorgekom in die Lourensford Landgoed persele nie.

Thesis (MScAgric)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: The macro-element uptake and distribution by higher density central leader ‘Donnarine’ nectarine trees was studied through the sequential excavation of trees. A large portion, 41.5%, of the nitrogen manifested in the new growth from dormancy up to pit-hardening, originated from nitrogen reserves in the permanent structure. The permanent structure was also an important source of phosphorous reserves. Of the phosphorous in the fruit, leaves and new shoots at pit-hardening, 35.0% came from reserves in the permanent structure. Potassium did not act as an important reserve in the nectarine trees and was taken up throughout the season. From pit hardening to harvest the fruit represented the most important sink for potassium. Calcium and magnesium, like potassium, did not play significant roles as reserves in the nectarine tree and must be available for uptake from the beginning of the season for new growth and development as well as fruit quality. The micro-element uptake and distribution was also studied through the sequential excavation of the same ‘Donnarine’ nectarine trees. Little scientific data is available on this topic. Manganese and iron was found to act as important reserves in the tree with 46.2% of manganese and 59.5% of the iron found in the new growth at pithardening coming from reserves translocated from the permanent structure. Zinc and boron reserves also play a role in nectarine trees, but to a lesser extent than manganese and iron. The seasonal mineral nutrient demand of the same ‘Donnarine’ nectarine trees was determined through the sequential excavation of trees and losses and fixation was calculated. Guidelines regarding nutritional requirements per ton of fruit produced per hectare by higher density nectarine orchards are respectively 3.82kg nitrogen, 0.35kg phosphorous, 4.43kg potassium, 1.53kg calcium, 0.52kg magnesium, 32.45g sodium, 9.44g manganese, 37.46g iron, 3.24g copper, 13.95g zinc and 10.52g boron. Sodium is not commonly considered to be essential to higher plants, but was included in the trial. Nutrient solutions with four different EC (electrical conductivity) levels were applied to ‘Donnarine’ nectarine trees under pulsating drip fertigation for three periods of different lengths, before harvest. Raising the nutrient solution EC to positively affect fruit quality is a technique widely utilised in the vegetable industry. This technique did, however, not have similar positive effects on nectarine fruit grown under a pulsating drip fertigation system. Good production practices such as accurate nutrition and irrigation as well as the correct horticultural inputs should be the primary focus of producers who wish to alter or improve the fruit quality of their crop. / AFRIKAANSE OPSOMMING: Voedingbestuur strategieë in nektarien boorde Die makro-element opname en verspreiding deur hoër digtheid sentrale leier ‘Donnarine’ nektarien bome is bestudeer d.m.v. opeenvolgende opgrawings van volledige bome en die ontleding van monsters. ‘n Groot hoeveelheid, 41.5%, van die stikstof wat tydens pitverharding in die nuwe groei teenwoordig was, is d.m.v. translokasie vanuit die permanente struktuur van die boom afkomstig. Die permanente struktuur was ook ‘n belangrike bron van fosfaat reserwes. Teen pitverharding was 35.0% van die fosfaat in die nuwe groei afkomstig vanuit die permanente struktuur. Bevindings het getoon dat kalium nie as ‘n reserwe in die nektarien bome opgetree het nie en dié element is deur die groeiseisoen opgeneem. Vanaf pitverharding tot en met oestyd was die vrugte die sterkste setel van aanvraag vir kalium. Kalsium en magnesium het, soos in die geval van kalium, nie ‘n belangrike rol as reserwe vertolk nie. Beskikbaarheid van hierdie elemente vir opname vanaf die begin van die groeiseisoen is dus baie belangrik vir nuwe groei en ontwikkeling asook vrugkwaliteit. Die mikro-element opname en distribusie van dieselfde ‘Donnarine’ nektarien bome is ook bestudeer d.m.v. opeenvolgende opgrawings en analise van volledige bome. Min wetenskaplike literatuur oor hierdie onderwerp is beskikbaar. Bevindings het getoon dat mangaan asook yster baie belangrike reserwes in die nektarien boom is. Tydens pitverharding was 46.2% van die mangaan en 59.5% van die yster wat in die nuwe groei teenwoordig was, afkomstig vanaf reserwes uit die permanente struktuur van die boom. Verder het sink en boor ook as reserwes opgetree, maar tot ‘n mindere mate as mangaan en yster. Die seisoenale behoeftes aan minerale voeding van dieselfde ‘Donnarine’ nektarien bome is bepaal d.m.v. opeenvolgende opgrawings en analise van volledige bome asook die bepaling van verwyderingsverliese en vaslegging. Voedingsriglyne is vasgestel i.t.v. die hoeveelheid voedingstof wat per hektaar benodig word om een ton nektariens te produseer. Die riglyne is as volg: 3.82kg stikstof, 0.35kg fosfaat, 4.43kg kalium, 1.53kg kalsium, 0.52kg magnesium, 32.45g natrium, 9.44g mangaan, 37.46g yster, 3.24g koper, 13.95g sink en 10.52g boor. Natrium word nie in die algemeen as ‘n essensiële plantvoedingselement beskou nie, maar is by die berekeninge ingesluit. Voedingsoplossing met vier verskillende vlakke van EG (elektriese geleiding) is vir drie periodes van verskillende lengtes aan ‘Donnarine’ nekarien bome toegedien. Die verhoging van die EG van voedingsoplossings ten einde kwaliteit te verbeter is ‘n tegniek wat met groot suskses in die groentbedryf toegepas word. Hierdie tegniek het egter nie soortgelyke positiewe effekte op die nektarien vrugkwaliteit gehad nie. Produsente wat hul vrugkwaliteit wil verbeter behoort primêr te fokus op goeie produksiepraktyke soos akkurate voeding en besproeiing asook die korrekte tuinboukundige insette.

Thesis (MScAgric (Horticulture))--Stellenbosch University, 2008. / Chemical thinning of fruit trees has become a central management practice for ensuring high fruit quality at harvest and return bloom the following season. Three trials were conducted in the 2004/5, 2006/7 and 2007/8 seasons to investigate the efficacy and mode of action of chemical thinning agents on European pear cultivars (Pyrus communis L) in the Western Cape, South Africa. The first trial was conducted in the 2004/5 and 2006/7 seasons to evaluate the efficacy of 50, 100 and 150 mg.l-1 6-benzyladenine (BA), and 30 and 40 mg.l-1 naphthylacetamide (NAD) on ‘Early Bon Chrétien’ pear. BA was more effective than NAD in reducing crop load and improving fruit size. Crop load decreased and fruit size increased with increasing rate of BA. BA significantly improved, whilst NAD failed to improve return bloom. In the second trial, three experiments were conducted in the 2006/7 and 2007/8 seasons to evaluate the efficacy of 100 to 200 mg.l-1 BA on ‘Forelle’ pear. The first experiment was conducted in the 2006/7 season where BA rates of 100, 125 and 150 mg.l-1 generally failed to reduce crop load or to improve fruit size and fruit size distribution and return bloom. The second experiment was conducted in the 2007/8 season where two BA rates, 150 and 200 mg.l-1 and a split-application of 3 x 50 mg.l-1 improved fruit size. The 200 mg.l-1 rate was the most effective treatment. BA did not improve fruit size distribution and return bloom. The third experiment was conducted in the 2007/8 season where the effect of rate and timing of BA applications was evaluated. Two rates, 150 and 200 mg.l-1 were applied 8, 11 and 17 days after full bloom (d.a.f.b.). There was no significant interaction between BA rate and application time. The 200 mg.l-1 rate and the 11 d.a.f.b. (i.e. 8 to 10 mm average fruit size) applications were more effective in reducing crop load, and improving fruit size. BA at 150 and 200 mg.l-1 and at all application times significantly improved return bloom relative to the control. From these trials we concluded that BA is a reliable thinner for ‘Early Bon Chrétien’ at rates of 100 or 150 mg.l-1. On ‘Forelle’, BA is not a reliable thinner and we recommended further trials with BA in combination with other thinning agents. In the third trial, three experiments were conducted in the 2007/8 season to investigate the mode of action and effect of BA application time on European pear cultivars. The effect of site of application, bourse shoot growth and fruit size at time of application on the efficacy of BA was evaluated. Results from the experiments on the effect of site of application and bourse shoot growth were inconclusive. In terms of fruit abscission, there was a significant interaction between BA application time and fruitlet size. Early BA applications (8 d.a.f.b.) were significantly more effective in promoting fruit abscission, than later (11 and 17 d.a.f.b.) applications. Smaller fruit (6 to 8 mm) were found to be more susceptible to BA-induced fruit abscission than bigger fruit (8 to 12 mm).

Thesis (MScAgric (Horticulture))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Persimmon production is new to South Africa with about 700 ha planted to the dioecious, parthenocarpic Triumph cultivar since 1998. Little local expertise is available to assist growers in achieving high yields of high quality fruit and previous research has shown that recipes that are followed in Israel, from where ‘Triumph’ was introduced to South Africa, do not necessarily have any beneficial effect in South Africa. ‘Triumph’ orchards in South Africa are often late in reaching full production. Persimmon trees are generally vigorous and prone to excessive fruit drop, partly due to excessive vegetative growth, especially when young and grown on the very vigorous Diospyros lotus seedling rootstock. The first objective of this study was to evaluate the use of growth retardants and various severities of girdling to increase flower formation, fruit set and yield in vigorous, young ‘Triumph’ orchards. Scoring and girdling improved fruit set and yield in two such orchards and are recommended as tools to improve yield in ‘Triumph’ in South Africa. Strapping, prohexadione-Ca (P-Ca) and paclobutrazol (PBZ) did not increase yield whereas 5 mm bark removal was too severe a treatment and decreased fruit quality in the current season and yield in the following season. None of the treatments had an effect on flower formation or decreased vegetative growth. PBZ, especially as foliar spray, appears to advance fruit maturity. P-Ca at 125 mg L-1 and 250 mg L-1 induced phytotoxicity symptoms and decreased yields in both orchards. However, further research is required before P-Ca and PBZ are completely discarded as treatments to manage vigor in ‘Triumph’ persimmon in South Africa. In contrast to the negative effect of excessive vigor on fruit production, the profitability of orchards is dependent on the rapid growth of trees after planting in order to fill the allotted canopy volume and achieve full production as quickly as possible. Hence, the second objective of this study was to determine optimum levels of irrigation and fertilizer application rates to attain early, high yields in newly planted ‘Triumph’. Fertigation was applied at three levels, viz. ½X, 1X and 2X with 1X being the commercial standard application rate. Irrigation was also applied at these levels without addition of fertilizer. In addition, fertilizer was applied at 0X, ½X and 1X at 1X irrigation level. Tree size increased with an increase in water application rate. Yield also increased linearly with an increase in water application rate due to a linear increase in fruit size. Fertigation and ½X water as well as an increase in fertilizer application rate at 1X irrigation substantially delayed fruit ripening. Hence, careful management of fertilizer and water application rate could be used to extend the harvesting period and, therefore, the marketing window of South African ‘Triumph’. We recommend that the trial be continued for a further few seasons so that the effect of water and fertilizer application rates on fruit quality and storability can be assessed. Fruit set may also be affected as trees reach their mature size with a concomitant increase in shading. / AFRIKAANSE OPSOMMING: Persimmonverbouing is ‘n nuwe bedryf in Suid-Afrika met ongeveer 700 ha van die tweeslagtige, partenokarpiese Triumph cultivar wat sedert 1998 aangeplant is. Min plaaslike kundigheid is beskikbaar om produsente van raad te bedien oor hoe om te werk te gaan om hoë opbrengste van hoë kwaliteit te verkry. Vorige navorsing het getoon dat resepte wat ‘Triumph’ van Israel na Suid-Afrika gevolg het, nie noodwendig suksesvol hier toegepas kan word nie. ‘Triumph’ boorde in Suid-Afrika neig om lank te neem alvorens hul hul maksimum produksievermoë bereik. Persimmons is oor die algemeen baie groeikragtig en geneig tot hoë vrugval, deels as gevolg van hul geil groei, en veral terwyl hulle jonk is en op die uiters groeikragtige Diospyros lotus saailingonderstam geënt is. Die eerste doelwit van hierdie studie was om die invloed van groei inhibeerders en verskillende grade van strafheid van ringelering op blomvorming, vrugset en oesopbrengs in jonk, sterk-groeiende ‘Triumph’ boorde te evalueer. Insnyding en ringelering met ‘n handsaag het vrugset en oeslading in twee groeikragtige boorde verbeter en word aanbeveel as geskikte ingrepe om die oeslading van ‘Triumph’ te verhoog. Draad-ringelering, en aanwending van prohexadione-Ca (P-Ca) en paclobutrazol (PBZ) het nie die opbrengs verhoog nie terwyl die verwydering van `n 5 mm strook bas té aggresief was en die vrugkwaliteit in die seisoen van toediening en opbrengs in die daaropvolgende seisoen verlaag het. Geen van die behandelings het blomvorming geaffekteer of vegetatiewe groei verminder nie. Dit wil voorkom asof PBZ, veral as blaartoediening, vrugrypwording kan versnel. Blare het tekens van fitotoksisiteit getoon na aanwending van P-Ca teen 125 mg L-1 en 250 mg L-1. P-Ca het ook die opbrengs in beide boorde aansienlik verlaag. Verdere navorsing is egter nodig alvorens P-Ca en PBZ sondermeer verwerp word as behandelings om die groei van ‘Triumph’ te beheer. Die winsgewendheid van boorde is afhanklik daarvan dat bome aanvanklik vinnig groei ten einde die toegekende boomryvolume so spoedig moontlik te vul en sodoende so vinnig as moontlik hul vol produksievermoë bereik. Bogenoemde is natuurlik teenstrydig met die negatiewe effek van uitermatige geil vegetatiewe groei op vrugproduksie. Die tweede doelwit van hierdie studie was dus om die optimale vlakke van besproeiing en bemesting te bepaal wat die vroeë aanvang van hoë opbrengste in nuwe ‘Triumph’ boorde sal verseker. Vloeibare bemesting is in kombinasie met besproeiing teen drie vlakke toegedien nl. ½X, 1X en 2X met 1X die kommersiële standaard vlak van toediening. Besproeiing is ook teen hierdie vlakke toegedien sonder dat kunsmis bygevoeg is. Addisioneel hiertoe is bemesting ook toegedien teen ½X, 1X en 2X teen 1X besproeiing. Boomgrootte het toegeneem met `n toename in die vlak van besproeiing. `n Lineêre toename in vruggrootte met ‘n toename in die vlak van besproeiing het ‘n oorsaaklike lineêre toename in opbrengs tot gevolg gehad. Bemesting in kombinasie met besproeiing, ½X besproeiing sonder bemesting, asook `n toename in die bemestingsvlak by 1X besproeiing het vrugrypwording substansieel vertraag. Die omsigtige bestuur van bemesting- en besproeiingsvlakke kan moontlik gebruik word om die oesperiode, en dus die bemarkingsvenster, vir Suid-Afrikaanse ‘Triumph’ te verleng. Ons beveel aan dat die proef vir ‘n vêrdere aantal seisoene voortgesit word sodat die effek van bemesting- en besproeiingsvlakke op vrugkwaliteit en -houvermoë bepaal kan word. Verhoogde oorskaduwing soos wat bome van sekere behandelings hul toegekende spasie bereik en oorskry, kan ook in die toekoms ‘n invloed op vrugset uitoefen.