The aim of the thesis was to compile a review of literature on the species Actinidia arguta and other main representatives of this genus (Actinidia deliciosa and Actinidia kolomikta), together with a description of the genus Actinidia. For selected genotypes to determine the content of the substance in the flesh and skins of species Actinidia arguta (varieties 'Issai', 'Ananasnaya' a seedling 1) and Actinidia deliciosa (varieties 'Hayward' and 'Sorelli'). Mentioned representatives described their origin and distribution, botanical characteristics, varietal characteristics, their habitat requirements, methods of reproduction and substances contained in fruits. The experimental part deals with the determination of ascorbic acid, all acids, antioxidants, soluble solids content and the determined methods FRAP and DPPH. The results of individual measurements were processed and statistically analyzed. The values obtained were sorted into tables and graphs, and subsequently described in the text part.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Includes bibliographic references.

O kiwizeiro pertence ao gênero Actinidia e família Actinidiaceae. Todas as espécies deste gênero são trepadeiras perenes que se comportam de forma desordenada quando não manejadas e caracterizam-se por crescimento extremamente vigoroso. O objetivo deste trabalho foi avaliar o comportamento vegetativo e produtivo de kiwizeiros das cultivares ‘Elmwood’ (Actinidia deliciosa) e ‘MG06’ (Actinidia chinensis), enxertados sobre plantas oriundas de sementes de frutos da cultivar ‘Bruno’ (Actinidia deliciosa), conduzidos em sistema latada e submetidos a diferentes intensidades de poda de inverno, além de testar a possibilidade de utilização da técnica de ‘tip squeezing’ (“compressão do meristema apical” - CMA) para redução do vigor e do crescimento de parte aérea de kiwizeiros ‘MG06’, na região da Serra Gaúcha, RS, Brasil. O primeiro estudo foi realizado de junho de 2016 a abril de 2017 com a cultivar ‘Elmwood’. Nesse, três tratamentos com nove repetições foram utilizados no delineamento inteiramente casualizado. Os tratamentos consistiram na manutenção de diferentes níveis de cargas de gemas em cada vara: 10, 15 e 20 gemas vara-1. Avaliou-se o índice de fertilidade das gemas; o número, percentual e posição de gemas não brotadas, brotações vegetativas e brotações mistas; área, massa seca e área específica das folhas; diâmetro e comprimento de ramos; rendimento e número de frutos; e diâmetros transversal e longitudinal, massa fresca, firmeza, teor de sólidos solúveis (SS), pH, acidez total titulável (ATT) e relação SS/ATT de frutos. O segundo estudo foi realizado entre julho e dezembro de 2017 com a cultivar ‘MG06’, testando-se diferentes cargas de gemas em cada vara: 10, 15 e 20 gemas vara-1, com e sem a utilização da CMA, representando 6 diferentes tratamentos. Cada tratamento era composto de nove repetições (cada repetição correspondia a uma planta) em delineamento inteiramente casualizado. Avaliou-se o índice de fertilidade das gemas; o número, percentual e posição de gemas não brotadas, brotações vegetativas e brotações mistas; área e massa seca das folhas; diâmetro e comprimento de ramos e de entrenós; diâmetros transversal e longitudinal, massa fresca, firmeza, teor de sólidos solúveis, acidez total titulável e relação SS/ATT de frutos. A poda com diferentes cargas de gemas não influencia o índice de fertilidade real das gemas de kiwizeiros ‘Elmwood’ e ‘MG06’ em um mesmo ciclo, porém afeta o tamanho das folhas e dos ramos. A poda de kiwizeiros ‘Elmwood’ mantendo varas com 10 gemas favorece o aumento da massa de fruto e não reduz produtividade. A CMA reduz o vigor das brotações de kiwizeiros ‘MG06’ sem influir na qualidade dos frutos. / The kiwifruit belongs to Actinidia Genus and Actinidiaceae Family. All species from this kind are perennial bindweeds which behave in desordered way when not managed and are characterized by extremely vigourous growth. The objective of this work is to evaluate vegetative and productive behavior of kiwifruit trees from ‘Elmwood’ (Actinidia deliciosa) and ‘MG06’ (Actinidia chinensis) cultivars, grafted over plants originating from seeds of fruits of the ‘Bruno’ cultivar (Actinidia deliciosa), conduced in trellis system and submitted to different intensities of winter pruning, besides testing the possibility of usage of ‘tip squeezing’ technique for vigor and growth reduction of the vegetative part of ‘MG06’ kiwifruit trees, in Serra Gaucha region, RS, Brazil. The first study has been made from june of 2016 to april of 2017 with ‘Elmwood’ cultivar. In this one, three treatments with nine repetitions (each repetition corresponded to a plant) were used in the completely randomized design. The treatments consisted in maintenance of different bud loading levels in each cane: 10, 15 and 20 buds cane-1. It was evaluated the index of fertility of the buds; the number, percentage and position of not sprouted buds, vegetative buds and mixed buds; area, dry mass and specific area of the leaves; diameter and length of the branches; productivity and number of fruits; and transversal and longitudinal diameters, dry mass, firmness, soluble solids content (SS), pH, titratable total acidity, (TTA) and relation SS/TTA of the fruits. The second study has been made between july and december of 2017 with ‘MG06’ cultivar, being tested different loads of buds in each cane: 10, 15 and 20 buds cane-1, with and without the usage of the “squeezing”, representing 6 different treatments. Each treatment was compound of nine repetitions in completely randomized design. It was evaluated the index of fertility of the buds; number, percentage and position of the not sprouted buds, vegetative buds and mixed buds, area and dry mass of the leaves; diameter and length of branches and internodes; transversal and longitudinal diameters, fresh mass, firmness, SS, TTA and relation SS/TTA of the fruits. The pruning with different loads of buds doesn’t influence the index of real fertility of the buds from ‘Elmwood’ and ‘MG06’ kiwifruit trees in a same season, however it affects the size of leaves and branches. The pruning of ‘Elmwood’ kiwifruit trees maintaining canes with 10 gems favors the increase of fruit mass and it doesn’t reduce productivity. The “tip squeezing” reduces the vigor of kiwifruit trees ‘MG06’ without influencing fruits quality.

Memoria para optar al Título Profesional de Ingeniera Agrónoma / El objetivo de este estudio fue evaluar el efecto de diferentes concentraciones de 1-metilciclopropeno (1-MCP) sobre la maduración de kiwi (Actinidia chinensis) ‘Jintao’. Los frutos una vez cosechados, provenientes de la localidad del Lontué, fueron trasladados al laboratorio de AgroFresh, donde se realizó el tratamiento de curado por 48 horas. Se evaluó color de pulpa (101,2±1,9 H º), firmeza de pulpa (9,1±2,5 Lbf) y solidos solubles (15,3±1,2 º Brix) de 130 frutos para determinar estado inicial. Se embalaron en cajas con 100 unidades. Se enfriaron para luego aplicar las diferentes concentraciones (500 ppm y 1000 ppm) de 1-MCP (SmartFresh, 0,14 % i.a) por 24 horas a 0 °C. Luego de almacenar por 60 días a 0 °C la fruta tratada y la no tratada (control) se aplicó etileno (34 mL) por 6 horas a 20 °C a la mitad de cajas de cada tratamiento, generando 6 tratamientos, T: almacenamiento refrigerado a 0 °C, T+E: Almacenamiento refrigerado a 0 ºC+aplicación de etileno, M1: Almacenamiento refrigerado con aplicación de 500 ppm 1-MCP, M1+E: almacenamiento refrigerado con aplicación de 500 ppm de 1-MCP+aplicación de etileno, M2: Almacenamiento refrigerado a 0 °C con aplicación de 1000 ppm de 1-MCP, M2+E: almacenamiento refrigerado con aplicación de 1000 ppm de 1-MCP+aplicación de etileno. Se hicieron evaluaciones a salida de frío a los 60, 90 y 120 días de: color de pulpa (H °), firmeza de pulpa (Lbf), contenido de sólidos solubles (%), tasa de producción de etileno (μL C2H4∙kg−1∙h−1), tasa de respiración (mL CO2∙kg−1∙h−1). Además luego de 90 y 120 días a 0 °C, se hizo un periodo de comercialización simulada (7 días a 20 °C) para una caja de cada tratamiento, donde se evaluó los mismos parámetros que a salida de frío agregando dureza de columela y acidez titulable. Ambas concentraciones de 1-MCP lograron evitar la caída de firmeza de pulpa, aumentando la vida postcosecha a 0 °C hasta los 120 días de almacenamiento. La aplicación de mayor concentración de 1-MCP, tuvo un efecto inicial mayor en el mantenimiento de la firmeza de pulpa que la aplicación de menor concentración, pero a lo largo del tiempo de almacenaje en frío y periodo de comercialización simulada, ambas perdieron su efectividad. No hubo diferencias estadísticamente significativas sobre los parámetros de calidad evaluados entre las diferentes concentraciones de 1-MCP. La aplicación de etileno, no tuvo un efecto estadísticamente significativo en conjunto con las aplicaciones de 1-MCP, además no logró disminuir la dureza de columela.

The chlorophyll degradation pathway is central to a number of plant processes including senescence and fruit ripening. However, the regulation of the chlorophyll degradation pathway enzymes is not well understood. The aim of this thesis was to elucidate the genetic mechanisms that control changes in pigment composition leading to fruit flesh yellowing in kiwifruit. Actinidia deliciosa and A. chinensis fruit, which are green and yellow, respectively, provide an opportunity to study the regulation of chlorophyll levels. The expression of genes that code for enzymes of the chlorophyll and cytokinin metabolic pathways was measured using qRT-PCR. Candidates for chlorophyll degradation regulatory points were then characterised for functionality by transient transformation in N. benthamiana. The endogenous cytokinin levels were measured in kiwifruit and transient activation assays were carried out with the promoters of key candidate genes. Overall, expression of the chlorophyll degradation genes was elevated in yellow fruit and expression of biosynthetic genes was higher in green fruit. The chlorophyll degradation-associated protein, STAY-GREEN2 (SGR2), was more highly expressed in yellow fruit, and transient over-expression of SGR was sufficient to drive chlorophyll degradation. Expression of isopentenyl transferase (IPT), the rate-limiting step for cytokinin biosynthesis, showed an increase towards maturity in green fruit, but not in yellow fruit. However, both fruit had similar high levels of cytokinin nucleotides and free bases. A gene coding for O-glucosylation was also highly expressed in green fruit. Green fruit contained higher levels of cytokinin O-glucosides and ribosides towards maturity, suggesting differences in cytokinin signalling, which could lead to regulation of chlorophyll levels via activation of the SGR promoter by transcription factors. It is likely that the chlorophyll degradation pathway and cytokinin metabolism are linked. The differential expression of cytokinin response regulators could lead to differential regulation of cytokinin levels in the fruit of the two species, and possibly differential regulation of the chlorophyll degradation pathway. Progress towards elucidation of the control of chlorophyll levels provides knowledge of this key process in kiwifruit and potentially gene-based markers for breeding new kiwifruit cultivars.

No Brasil, a propagação do kiwizeiro (Actinidia sp) é realizada através da enxertia, com porta-enxertos provenientes de sementes, que pode resultar na perda das características agronômicas de interesse, além de plantas morfofiosiologicamente desuniformes no pomar. Uma possibilidade, tanto para obtenção da variedade copa, como de porta-enxerto clonal, é a estaquia. O presente estudo tem como objetivos identificar a época do ano mais favorável para realizar a estaquia, o potencial de enraizamento de diferentes genótipos de kiwizeiro, bem como determinar a concentração exógena de AIB mais eficiente neste processo. No primeiro estudo, foram realizadas coletas de material propagativo nos meses de maio, agosto e dezembro de 2016 e março de 2017 da cultivar ‘Bruno’ (Actinidia deliciosa). As estacas foram elaboradas deixando-se duas gemas e metade da área de uma folha madura, as quais foram submetidas, na sua base, ao tratamento com AIB, nas concentrações de zero, 1.000, 2.000 e 4.000 mg L-1. Após 90 dias em ambiente protegido com sistema de nebulização intermitente, avaliou-se a percentagem de estacas enraizadas; percentagem de estacas mortas; percentagem de estacas brotadas; percentagem de estacas com retenção foliar; comprimento médio das três maiores raízes e número de raízes por estaca. Os tratamentos com AIB influenciam a percentagem de enraizamento das estacas de kiwizeiro ‘Bruno’ coletadas no mês de março com 36,07% de enraizamento na concentração de 2.320 mg L-1, e em dezembro, com uma resposta linear, obtendo-se 57,59% de enraizamento na concentração de 4.000 mg L-1 de AIB. No segundo estudo, durante a primavera, foi coletado material propagativo das cultivares ‘Bruno’, ‘Elmwood’ e ‘Matua’ (A. deliciosa) e ‘MG06’(A. chinensis), cujas estacas foram submetidas ao tratamento com zero, 1.000, 2.000, 4.000, 6.000 e 8.000 mg L-1 de AIB. Avaliou-se a percentagem de estacas enraizadas; percentagem de estacas com calos; percentagem de estacas com retenção foliar; comprimento das três maiores raízes; número e massa da matéria seca de raízes. Estacas herbáceas da cultivar ‘MG06’ e ‘Bruno’ foram as que apresentaram maior percentagem de enraizamento e, as da cultivar ‘Matua’, o menor. Em relação às concentrações de AIB, para as diferentes cultivares, observou-se saturação da resposta na dose de 4.640 mg L-1, em que se pode obter 48,9% de enraizamento. / In Brazil, the kiwifruit (Actinidia sp) propagation is usually done through grafting onto rootstocks obtained from seeds, it can results in the loss of desirable agronomic characteristics, as well as morphophysiologically uneven plants in the orchard. One possibility, both to obtain the scion variety and the clonal rootstock, is by cutting. The present study aims to identify the most favorable time of the year for cutting, the rooting potential of different genotypes of kiwifruit, as well as to determine the exogenous concentration of IBA (indolbutyric acid) most efficient in this process. In the first experiment, propagation material of cultivar ‘Bruno’ (Actinidia deliciosa) was collected in May, Augost and December/2016 and March 2017. The cuttings were prepared by leaving two buds, keeping half of a leaf in the upper bud. A hydroalcoholic IBA solution at concentrations 0, 1.000, 2.000 and 4.000 mg L-1 was applied at the base of the cuttings by dipping for seven seconds. The percentage of rooted cuttings; percentage of dead cuttings; percentage of sprouted cuttings; percentage of cuttings with leaf retention; medium-length of the three largest roots and number of roots by cuttings, were evaluated 90 days later. Spring was the season where the best response to rooting was observed, while summer was the worst. The IBA treatments positively influenced the rooting percentage in the March, with 36.07% of rooted cuttings at the dose of 2.320 mg L-1, and in the December, obtained a linear response, with 57.59% rooting at the 4.000 mg L-1 concentration of AIB. In the second experiment, propagating material of the cultivars 'Bruno', 'Elmwood' and 'Matua' (A. deliciosa), 'MG06' (A. chinensis) were harvested in December/2016, were submitted to treatment with zero, 1.000, 2.000, 4.000, 6.000 and 8.000 mg. L-1 of IBA. Parameters of percentage of rooted cuttings; percentage of cuttings with calluses; percentage of cuttings with foliar retention; length of the three largest roots; number and mass of root dry matter were recorded. Herbaceous cuttings of the 'MG06' and ‘Bruno’ cultivar showed the highest percentage of rooting and the 'Matua' cultivar, the lowest. In relation to the IBA concentrations, for the different cultivars, saturation of the response was observed at the dose of 4.640 mg L-1, where 48.94% of rooting was recorded.

Memoria para optar al Título Profesional de: Ingeniero Agrónoma / El objetivo de la presente investigación fue estudiar el consumo de kiwi (Actinidia deliciosa) fresco en la comuna de Maipú, Región Metropolitana, Chile. Maipú es una de las comunas más grandes de la Región y presenta una distribución de estratos socioeconómicos similares al resto de la población. Se realizó un sondeo de la oferta disponible de kiwi, tanto en Lo Valledor como en supermercados y ferias libres, de la Región Metropolitana, entre los meses de octubre y noviembre del año 2012. Como segunda etapa, se realizó una encuesta en los meses de marzo y abril del 2013, que constituyó la principal fuente de información para esta investigación. Dicho instrumento, se elaboró con 100% de preguntas de tipo cerrada. Éste se aplicó a una muestra no probabilística por conveniencia de 459 personas, siendo 400 consumidores de kiwi fresco y 59 no consumidores. A partir de esto, se evaluaron distintas características de este grupo de personas: sociodemográficas, hábitos de consumo y de compra, actitudes de los consumidores y segmentos, así como preferencias hacia el consumo. Además, se abordaron las razones del por qué esas 59 personas no consumían kiwi. En el análisis se utilizaron técnicas de análisis univariado y multivariado (análisis factorial, conglomerado y conjunto). Por medio del análisis de componentes principales, se identificaron las dimensiones que explican las actitudes hacia el consumo, ellos fueron: Información del producto (23,11%), Funcionalidad (15,01%), Oportunidad (8,81%) y Bienestar (8,27%), los cuales fueron capaces de explicar el 55,3% de la varianza y con un KMO de 0,669. Luego, se identificaron tres segmentos de consumidores: Reticentes (35%), Flexibles (31,25%) y vida sana (33,75%). Las preferencias en cada segmento fueron: Reticentes; 18,82% (Sistema de Producción), 26.06% (Precio) y 55,12% (Forma). Flexibles; 21,86% (Sistema de Producción), 25,99% (Precio) y 50,55% (Forma). Vida Sana; 21,96% (Sistema de Producción), 27,6% (Precio) y 50,4% (Forma). El segmento Reticente no muestra una tendencia clara hacia la Disposición a Pago, no así el segmento Flexible y el Vida Sana que en su mayoría estarían dispuestos a pagar más por un kiwi orgánico y por un kiwi envasado, pelado y trozado, existiendo mayor probabilidad de compra si en general conocen las diferencias nutricionales con otras frutas. Respecto a los entrevistados que se declararon no consumidores del producto en cuestión, el motivo que prevalece es “no me agrada su sabor” y “me incomoda la cáscara del kiwi”. Las acciones de marketing en el mercado interno deberían centrarse en los atributos intrínsecos y extrínsecos del kiwi, con publicidad y promoción. / The main objective of this research was to study the consumption of fresh kiwi(Actinidia deliciosa) in the district of Maipú, Metropolitan Region, Chile. Maipú is one of the largest district of the Region, being a socioeconomic level distribution similar to the rest of the population. During October and November 2012, as a first step of the study, an exploration of the available supply of kiwi was made, through Lo Valledor distribution center, Supermarkets and streetmarkets. A inquiry was made during March and April 2013, resulting the main source of information for this research. This instrument was developed with 100% closes type questions. This was applied to a no probabilistic sample of convenience of 459 people, with 400 consumers of fresh kiwi and 59 nonconsumers. Different characteristics were evaluated to this group of people: Sociodemographic, spending habits and buying habits consumer, attitudes and segments, as well as preferences for consumption. Moreover, reasons have been discused why these 59 people did not eat kiwi. Techniques univariate and multivariate analysis (factorials analysis, cluster and conjoit) was used in the analysis. Product information (23,11%), Functionality (15,01%), Opportunity (8,81%) and Wellness (8,27%), have been identified as the dimensions explaining the different attitudes towards consumptions, which were able to explain 55,3% of varience with a KMO of 0,669, through of principal component analysis. Three consumer segments were identified: Reticent (35%), flexible (31,25%) and healthy life (33,75%). Preferences for each segment were: Reticent; 18.82% (Production System), 26.06% (price) and 55.12% (Shape). Flexible; 21.86% (Production System), 25.99% (price) and 50.55% (Shape). Lifestyle; 21.96% (Production System), 27.6% (price) and 50.4% (Shape). The Reticentnt segment do not shows marked tendency towards Willingness to Pay, additionally the Flexible and Lifestyle segment willing to pay more for an organic kiwifruit and for packaging, peeling and bucking kiwifruit, have been more likely to exist purchase if generally known nutritional differences with other fruits. Those who declared to be non kiwi consumer indicated reasons as "not like the taste" and "kiwi peel makes me uncomfortable”. The marketing in the internal market should focus on intrinsic and extrinsic attributes kiwi, advertising and promotion.

Made available in DSpace on 2016-12-08T16:44:34Z (GMT). No. of bitstreams: 1 PGPV08MA044.pdf: 355822 bytes, checksum: 1fe501d96a7d73a1fe7a14d6e9a58c69 (MD5) Previous issue date: 2008-11-19 / This research was carried out to study the effects of controlled atmosphere storage (CA, with ethylene scrubber) and the treatment with the inhibitor of ethylene action, 1- metilciclopropeno (1-MCP) on postharvest quality preservation of Bruno , Monty and Hayward kiwifruits (Actinidia deliciosa). Hayward, Bruno and Monty kiwifruits were harvested in April of 2003 and 2004, in Fraiburgo, SC. After harvest, fruits were treated with 1.0 &#956;L.L-1 of 1-MCP or left untreated (control), and then stored under air (AA; 0.0 ± 0.5°C / 90± 3% RH) or CA (2.0kPa + 4.5kPa CO2 / 0°C ± 0.5°C and 92 ± 3% RH, with ethylene scrubber) conditions. Fruit were assessed at harvest and periodically during cold storage. Fruit left under AA were assessed after 30, 60, 90 and 120 days, while fruit left under CA were assessed after 60, 90, 120 and 150 days in cold storage, followed by seven days at 23°C. Fruits were analyzed in terms of flesh firmness, soluble solids content (SSC), titratable acidity (TA), ethylene production, respiration, and incidence of physiological disorders. The experiment followed a completely randomized design. The data were subjected to analysis of variance, and the least significant difference (LSD) between treatment means was assessed by Fischer`s least significant difference test (p<0.05). The benefits of treatment with 1-MCP on fruit postharvest quality preservation were observed on both, AA and AC (with ethylene scrubber) storage.The response to 1-MCP treatment was affected by cultivar and storage duration. The treatment with 1-MCP delayed the increase in ethylene production and respiration after removal from cold storage in all cultivars. The reduction of ethylene and respiration by 1-MCP delayed flesh firmness and TA loss, and reduced the development physiological disorders. The treatment with 1-MCP had no effect on SSC. Fruits stored in air showed a high metabolism, resulting in low storage potential, even when treated with 1-MCP. There was an additive effect of treatment with 1-MCP and CA storage with ethylene scrubbing on fruit postharvest preservation / O presente estudo teve por objetivo determinar os efeitos da atmosfera controlada (AC) com catalisador de etileno e do inibidor da ação do etileno 1-MCP, sobre a conservação da qualidade pós-colheita de kiwi (Actinidia deliciosa), cultivares Bruno, Monty e Hayward. Kiwis Bruno , Monty e Hayward foram colhidos em abril de 2003 e 2004 em Fraiburgo, SC. Após a colheita, parte dos frutos foi tratada com 1,0 &#956;L.L-1 de 1-MCP e, então, armazenados em condições de atmosfera do ar (AA; 0,0 ± 0,5oC e UR 90 ± 3%) ou atmosfera controlada (AC; 2,0kPa de O2 + 4,5kPa de CO2 / 0oC ± 0,5oC e UR 92 ± 3%, com a presença de catalisador de etileno). Frutos foram analisados na colheita e periodicamente durante armazenagem. As avaliações foram realizadas após 30, 60, 90 e 120 dias de armazenagem sob AA e 60, 90, 120 e 150 dias de armazenagem sob AC, com catalisador de etileno, mais um e sete dias a 23oC. Os frutos foram analisados quanto à firmeza da polpa, teor de sólidos solúveis (SS), acidez titulável (AT), taxa de produção de etileno, taxa respiratória e incidência de distúrbios fisiológicos. O experimento foi conduzido em delineamento inteiramente casualizado. Os dados foram submetidos à análise da variância e as diferenças entre tratamentos determinadas por teste de separação de médias de Fischer (p<0,05). Os benefícios do tratamento com 1-MCP sobre a conservação da qualidade foram observados tanto para frutos armazenados sob AA quanto sob AC (na presença de catalisador de etileno). De maneira geral, as respostas do 1-MCP foram influenciadas pela cultivar e período de armazenagem. O tratamento com 1- MCP retardou o aumento acentuado da taxa de produção de etileno e da taxa respiratória de kiwi após remoção de câmara fria em todas as cultivares. A redução da taxa de produção de etileno e da taxa respiratória pelo tratamento 1-MCP foi associada ao aumento da conservação da firmeza da polpa e da AT, e redução do desenvolvimento de distúrbios fisiológicos. O tratamento com -MCP não apresentou efeito significativo sobre o conteúdo de SS. Frutos armazenados sob AA apresentaram alto metabolismo resultando em baixo potencial de armazenagem, mesmo quando tratados com 1-MCP. Houve efeito aditivo do tratamento 1-MCP mais armazenagem sob AC com eliminação do etileno sobre a conservação dos frutos

Repeat purchase of kiwifruit is primarily driven by consumer judgement of internal fruit quality attributes, including those affected by dry matter concentration (DMC) and mineral composition in fruit. This research investigated mechanisms affecting carbohydrate, mineral and water accumulation in 'Hayward' kiwifruit (Actinidia deliciosa), and related these to specific management practices. Canopy manipulation through pruning and treatments such as artificial pollination, defoliation, girdling, thinning and application of the auxin transport inhibitor TIBA, may affect fruit DMC and mineral composition. Leaf photosynthesis and fruit dry matter concentrations (DMC) started to decline as leaf area index values increased above 3-4. In addition to reducing competition for carbohydrates between vegetative and reproductive growth, leader pruning probably increased DMCs of fruit in the leader zone by improving light interception. Photosynthesis was not affected by crop loads between 20- 60 fruit m-2, but was consistently higher on non-terminating (long) shoots than on terminating (short) shoots, as were fruit DMCs. Differences in photosynthetic rate of leaves on these two shoot types were attributed to differences in shoot exposure to the sun, and also to the greater demand for carbohydrate within long shoots. Leaves subtending fruit may increase Ca, and to a lesser extent Mg, flow into fruit, however their accumulation was not affected by leaves outside the fruiting shoot. Xylem sap Ca and Mg concentrations were higher in shoots with a high rather than a low leaf: fruit (L:F) ratio and this may, at least partially, relate to the increase in shoot transpiration that occurs as shoot L:F ratios increase. Within vine variation in fruit Ca concentrations may reflect variations in xylem sap flow rates and Ca concentrations of xylem sap reaching fruit. Calcium translocation may occur independently of ion movement in the transpiration stream. Timing and extent of vascular differentiation in flower and fruitlet pedicels, possibly regulated by auxin, may influence fruit Ca accumulation. It is likely that early differentiation of vascular tissue in flower and fruitlet pedicels influenced cell division and subsequent (carbohydrate) sink strength of fruit by determining availability of carbohydrate for partitioning into cell walls. While growers have the potential to induce minor changes in fruit DMC, further increases will depend on the separation of carbohydrate and water accumulation. Further research is required to elucidate the mechanisms regulating phloem transport and unloading of sucrose in kiwifruit.

Memoria para optar al título profesional de: Ingeniero Agrónomo / El presente estudio se realizó con el objetivo de comprobar la patogenicidad de Verticillium albo-atrum, hongo asociado al decaimiento y muerte de plantas de kiwi dorado (Actinidia chinensis) cultivar Hort16A. Con este propósito plantas de Hort16A de un año de edad injertadas sobre Hayward (Actinidia deliciosa) se inocularon con una suspensión conidial de 106 conidias·ml -1. Al cabo de sesenta días, solamente las plantas inoculadas con V. alboatrum manifestaron síntomas de clorosis, marchitez y defoliación. Desde plantas con síntomas se recuperó en medio de cultivo Agar Agua y Agar Papa Dextrosa a V. alboatrum, identificado morfológicamente y mediante la amplificación del espacio intergénico entre los genes 18S y 28S que codifican para el RNA ribosomal del micelio del hongo. Desde tejido vegetal de plantas de kiwi dorado con síntomas se comprobó la presencia de V. albo-atrum utilizando la técnica de PCR anidado. Se realizó un estudio comparativo de la morfología y temperatura óptima de desarrollo entre V. albo-atrum y V. dahliae. Destacándose como la principal diferencia morfológica la presencia de hifas melanizadas en V. albo-atrum y la formación de microesclerocios en V. dahliae. La temperatura óptima de crecimiento para V. albo-atrum fue de 20°C y de 25°C para V. dahliae. / The objective of this study was to verify the pathogenicity of Verticillium albo-atrum, fungi associated with decline and death of gold kiwifruit (Actinidia chinensis) cultivar Hort16A. For this purpose Hort16A plants of one year old grafted on Hayward (Actinidia deliciosa) were inoculated with a suspension of 106 conidias·ml -1. After sixty days, only plants inoculated with V. albo-atrum showed symptoms of chlorosis, wilting and defoliation. The isolated fungus from symptomatic plant was recovered in water agar and potato dextrose agar medium and identified morphologically and by amplification of intergenic space between rRNA 18S and 28S coding genes of V. albo-atrum mycelium. From symptomatic plants tissue was detected the presence of V. albo-atrum using nested PCR. It was performed a comparative study of morphology and optimum temperature growth between V. albo-atrum and V. dahliae, being the main morphological difference the presence of melanized hiphae on V. albo-atrum and of microesclerotia on V. dahliae. The optimum growth temperature of V. albo-atrum and V. dahliae were 20°C and 25°C respectively.