Conventional stripping of burley tobacco is labor intensive and typically requires 50 to 75 worker hours per acre (wkr•hr/ac). The goal of the project was to reduce labor by optimizing leaf removal by string trimmer heads using combinations of strings lengths and motor speeds. In tests conducted on a single grade, all leaves outside the grade were removed by hand. Plants were run through the machine for sting lengths of 5, 7 and 9 inches and associated motor speeds which were monitored and recorded. Stripping efficiencies were calculated for each plant and collectively for each set of four plants. The machine was then tested for three grade stripping efficiency. Particle size analysis tests were run to determine potential losses due to leaf shredding. Efficiencies for single grade testing ranged from 93 to 96% for optimal string length and speed combinations. Stripping three grades by machine resulted in an average of 97% efficiency. Potential losses due to shredding accounted for 5.6% of the total weight mechanically removed. It is believed that this stripping concept, implemented on a full scale four grade basis, could result in savings of at least 18 wkr •hr/ac [45 wkr•hr/ha].

Current fruit-zone management recommendation in the eastern US aims for 1-2 basal shoot leaf layers after fruit set to limit fungal disease and sunburn incidence, and prevent extreme heating of grapes. The goal of this work was to assess if fruit-zone leaf removal to an uncommonly greater extent, and/or at an earlier phenological stage, would favorably alter yield components or fruit composition in three popularly grown, red-fruited, Bordeaux varieties – Cabernet franc, Petit Verdot, and Cabernet Sauvignon. Pre-bloom leaf removal to various extents reduced crop yield by 41-78% when compared to no leaf removal across seasons and varieties. Pre-bloom leaf removal implementation in consecutive seasons tended to further reduce crop yield components compared to implementation in the first year. Pre-bloom leaf removal tended to reduce cluster compactness and bunch rot incidence when compared to post-fruit set and no leaf removal. Basal leaf removal to the greatest extents inconsistently reduced soluble solids and titratable acidity across varieties and seasons. Pre-bloom and post-fruit set leaf removal to the greatest extent consistently increased total grape phenolics and anthocyanins compared to no leaf removal in Cabernet Sauvignon, but inconsistently increased total grape phenolics compared to no leaf removal in Cabernet franc and Petit Verdot. Basal leaf removal to the greatest extents tended to increase the synthesis and degradation of carotenoids more consistently than no leaf removal, and this was particularly true for zeaxanthin. Petit Verdot and Cabernet franc wine color and aroma were inconsistently distinguishable between leaf removal treatments, and color intensity was rated higher in wines made with fruit from pre-bloom leaf removal compared to modest post fruit-set leaf removal plots. Waiting until after fruit set to remove fruit-zone leaves maintained crop yield and offered comparable improvements in fruit composition to pre-bloom leaf removal. Pre-bloom leaf removal of no more than four leaves is recommended to limit crop yield reduction, and modestly improve fruit composition. This work showed that fruit-zone leaf removal does not need to be conservative in the eastern US, particularly because the climate does not appear to be detrimental to fruit composition, and open fruit-zones reduce grape fungal disease incidence. / Ph. D.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The sustainability of the crop production, i.e. the ability to remain itself in the market, protecting the environment and have good financial returns is often threatened by risk factors. Among the risk factors in agriculture, highlights the climatic factor, and hail occurrence of extreme events of this factor. The objective of this study was to evaluate sunflower plants responses after application of different levels of injury in leaves in different phenological stages, to quantify the injury effect on the productivity reduction of achenes. In addition, mathematical models were developed to estimate the production reduction in function of crop development stage and occurrence intensity of injury in leaves. The experiments were conducted at Crop Science Department of the Federal University of Santa Maria, Santa Maria, RS, Brazil, in the agricultural years 2009/2010 and 2010/2011, following the growth and development of plants during the crop cycle through phenological and phenometric observations. The meteorological data were obtained from the meteorological station of Santa Maria, belonging to 8th DISME/INMET/MA. Were made sixteen treatments arranged in a randomized block design with three replications for the 2009/2010 agricultural year and fifteen treatments for the 2010/2011 agricultural year. The treatments consisted of four foliar injury levels (0, 25, 50 and 75%) applied at four phenological stages (20 emitted leaves, R2, R5.1 and R6) of sunflower plants in the experiment conducted in 2009/2010 and five foliar injury levels (0, 25, 50, 75 and 100%) applied at three phenological stages (20 emitted leaves, R2 and R6) of sunflower plants in 2010/2011. The injuries were promoted by perforations in leaf blade of all sunflower leaves with auger of 23, 25 and 30 mm in diameter. The number of perforations was set according of leaves width, auger diameter and desired injury level. The sunflower yield was affected by injury levels applied and by stages considered. The reproductive stage R2 was most affected by injuries, while 25% injury level had caused proportionally greater effect on sunflower yield. / A sustentabilidade da produção de uma cultura, isto é, a capacidade desta conservar-se no mercado, preservar o ambiente e ter bons retornos financeiros é frequentemente ameaçada por fatores de risco. Dentre os fatores de risco na agricultura, destaca-se o fator climático, e a ocorrência de granizo é um dos eventos extremos deste fator. O objetivo deste trabalho foi avaliar as respostas das plantas de girassol após a aplicação de diferentes níveis de injúria foliar, em diferentes estágios fenológicos, para quantificar o efeito dessa injúria na redução da produtividade de aquênios. Além disso, objetivou-se desenvolver modelos matemáticos de estimativa de redução de produção em função do estágio de desenvolvimento da cultura e da intensidade da ocorrência da injúria foliar. Os experimentos foram conduzidos junto ao Departamento de Fitotecnia da Universidade Federal de Santa Maria, Santa Maria, nos anos agrícolas de 2009/2010 e 2010/2011, acompanhando-se o crescimento e o desenvolvimento das plantas no decorrer do ciclo da cultura através de observações fenométricas e fenológicas. Os dados meteorológicos foram obtidos junto à estação meteorológica principal de Santa Maria, pertencente ao 8° DISME/INMET/MA. Foram realizados dezesseis tratamentos arranjados no delineamento de blocos ao acaso, com três repetições para o ano agrícola 2009/2010 e quinze tratamentos para o ano agrícola de 2010/2011. Os tratamentos constaram de quatro níveis de injúria foliar (0, 25, 50 e 75%) aplicados em quatro estágios fenológicos (20 folhas emitidas, R2, R5.1 e R6) das plantas de girassol para experimento conduzido em 2009/2010 e cinco níveis de injúria foliar (0, 25, 50, 75 e 100%) aplicados em três estágios fenológicos (20 folhas emitidas, R2 e R6) das plantas de girassol em 2010/2011. As injúrias foram promovidas por meio de perfurações no limbo foliar de todas as folhas das plantas de girassol realizadas com o auxílio de vazadores de 23, 25 e 30 mm de diâmetro. O número de perfurações era estipulado de acordo com a largura das folhas, diâmetro do vazador e nível de injúria pretendido. A produtividade do girassol foi afetada pelos níveis de injúria aplicados e pelos estágios considerados. O estágio reprodutivo R2 foi o mais afetado pelas injúrias, enquanto que a injúria de 25% foi a que promoveu proporcionalmente maior efeito na produtividade do girassol.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-02-26T14:04:16Z No. of bitstreams: 1 PGPV16MA197.pdf: 2230923 bytes, checksum: e668d82b2261743e59f2124d9315814d (MD5) / Made available in DSpace on 2018-02-26T14:04:16Z (GMT). No. of bitstreams: 1 PGPV16MA197.pdf: 2230923 bytes, checksum: e668d82b2261743e59f2124d9315814d (MD5) Previous issue date: 2016-07-13 / Capes / Highland regions of Santa Catarina State, Brazil, have been acquiring great importance due to the high potential for wine production from Vitis vinifera L. cultivars, but due to highlands of Santa Catarina State are being in an emergent wine grown region fundamental investigations into vineyard practices are necessary. This work aims to contribute to the generation of data that can direct the management of leaf removal in the vineyards in order to develop a differentiated quality wine, determining times of leaf removal in the varieties Cabernet Sauvignon and Sauvignon Blanc, and evaluate the its effect on vegetative, productive aspects, enological potential of grape wine quality, and the occurrence of bunch rot. The results of this study show the importance of management of leaf removal grapes wines, demonstrating its benefits in relation to technological and phenolic maturity indices, providing better quality grape, higher productivity and better vegetative balance. And the leaf removal, held between phenological full flowering stage and grain pea resulted in a significant reduction in the incidence and severity of bunch rot of Cabernet Sauvignon and Sauvignon Blanc grown in high altitudes of Santa Catarina. It is evident that the removal leaf vine is indispensable for obtaining a grape of high quality and sanity / As regiões de altitude de Santa Catarina vem despertando interesse de investidores, pela sua característica de elaborar vinhos de elevada qualidade. Porém, por ser uma atividade ainda recente nessas regiões, há uma grande demanda pela geração de informações técnicas adequadas, visto que possui características distintas das demais regiões vitícolas do Brasil. A presente dissertação visa contribuir na geração de informações que possam direcionar o manejo da desfolha nos vinhedos, a fim de elaborar um vinho de qualidade diferenciada, determinando o efeito de diferentes épocas de desfolha nas variedades Cabernet Sauvignon e Sauvignon Blanc sobre aspectos vegetativos, produtivos, potencial enológico da uva, qualidade do vinho, e na ocorrência de podridão cinzenta (Botrytis cinerea Pers) nos cachos. Os resultados deste estudo evidenciam a importância do manejo da desfolha da videira, demonstrando seus beneficios em relação aos índices de maturação tecnológica e fenólica, propiciando melhor qualidade da uva, maior produtividade e melhor equilíbrio vegeto:produtivo. Além disso, a realização de uma desfolha precoce, realizada entre os estádios fenológicos plena florada e grão ervilha resultaram em redução da incidência e severidade de podridão cinzenta (Botrytis cinerea) nos cachos das variedades Cabernet Sauvignon e Sauvignon Blanc cultivadas em elevadas altitudes de Santa Catarina. Evidencia-se que o manejo da desfolha da videira é indispensável para obtenção de uma uva de elevada qualidade e sanidade

Técnicas de cultivo para adaptar la viticultura mediterránea al cambio climático La viticultura mediterránea se está viendo afectada por el cambio climático, lo que amenaza la tipicidad del vino y, por tanto, la sostenibilidad de la vitivinicultura. Los principales factores que se prevé que afecten al cultivo de la vid son la escasez de agua, los incrementos térmicos y el aumento de la concentración de dióxido de carbono en el aire, lo que influirá en la vid: i) adelantando su fenología, disociando así la maduración tecnológica y fenólica de la uva y ii) incrementando las necesidades hídricas del viñedo. Éste trabajo pretende evaluar los efectos de diferentes técnicas de cultivo para la adaptación de la viticultura mediterránea al cambio climático. Se realizaron tres experimentos en Valencia (España) estudiando los efectos de: 1) el riego deficitario controlado; 2) la arquitectura de los sistemas de conducción y 3) el manejo del dosel vegetal. Las principales respuestas evaluadas fueron la eficiencia en el uso del agua de los viñedos (EUA) y la composición de la uva. El experimento 1 se llevó a cabo durante tres campañas en un viñedo de Moscatel de Alejandría/161-49C regado por goteo con el objetivo de definir la estrategia de riego más sostenible para uva blanca en el levante español. Para ello, se ensayaron cuatro tratamientos: (i) Testigo, regado al 100% de la evapotranspiración del cultivo (ETc) durante toda la campaña; (ii) riego deficitario sostenido (SDI), regado al 50% del Testigo; (iii) déficit temprano (ED), donde se restringió el riego antes del envero, seguido de un 100% de ETc; y (iv) déficit tardío (LD), regado como el Testigo hasta el envero y posteriormente al 25% de la ETc hasta la vendimia. La producción en el ED y el LD se redujo en un 25 y 15% respectivamente en comparación a la del Testigo, mientras que la producción del SDI no difirió significativamente del Testigo ni de los tratamientos de ED y LD. Todos los tratamientos con riego deficitario mostraron efectos acumulativos en la productividad de las cepas como consecuencia de la reducción del número de racimos por sarmiento y del tamaño del racimo debido al menor tamaño de la baya. El experimento 2 pone de manifiesto que la respuesta a la minimización de la radiación interceptada por el dosel vegetal es dependiente de la variedad y que reducir la carga de radiación en viñedos de clima mediterráneo podría tener efectos positivos en la EUA de la vid. La efectividad de la técnica de LLR parece depender de sus efectos sobre la relación área foliar/producción y el estado hídrico de la vid, la capacidad fotosintética compensatoria de la variedad y de las condiciones ambientales. Por consiguiente, en viñedos de baja vigorosidad, una defoliación severa puede no ser aconsejable para adaptar las variedades Bobal y Tempranillo al calentamiento global debido a los efectos perjudiciales sobre la calidad del vino tinto. Por el contrario, los resultados de los experimentos de riego deficitario y de orientación de las filas de espaldera proporcionan nuevos hallazgos en la EUA como posibles técnicas para paliar la escasez de agua en el viñedo. Por lo tanto, las técnicas de campo estudiadas resultan eficaces en adaptar la viticultura mediterránea al cambio climático en cuanto al estrés hídrico. Sin embargo, sus efectos en términos de mitigación del estrés térmico no fueron del todo positivos. Por tanto, es necesario realizar más investigaciones para determinar la viabilidad de emplear otras prácticas de campo, distintas al LLR, para equilibrar la madurez glúcida y fenólica de la uva. / Field practices for adapting Mediterranean viticulture to climate change Mediterranean viticulture is being affected by climate change, which threatens wine typicity and, therefore, the whole viticulture sustainability. The main factors expected to affect grapevine cultivation are water scarcity, warm air temperature and the increase in the air carbon dioxide concentration, and impact of these factors will be mainly the: i) advancing of grapevine phenology, thereby decoupling berry technological and phenolic composition and ii) increasing vine water requirements. This PhD Thesis aimed at evaluating the effects of different field practices to adapt Mediterranean grapevine cultivation to climate change. Three experiments were performed in Valencia (Spain) to assess the effects of 1) regulated deficit irrigation; 2) training systems architecture and; 3) canopy management. The main responses evaluated were vineyard water-use efficiency (WUE) and grape composition. Experiment 1 was undertaken for three seasons in a drip-irrigated, cv. Muscat of Alexandria/161-49C vineyard to define the most sustainable irrigation strategy for white winegrapes in eastern Spain. For this, four treatments were tested: (i) Control, irrigated at 100% of estimated crop evapotranspiration (ETc) for the entire season; (ii) sustained deficit irrigation (SDI), irrigated at 50% of Control; (iii) early deficit (ED), where pre-veraison irrigation was withheld, followed by 100% ETc; and (iv) late deficit (LD), irrigated as in the Control until veraison and thereafter at 25% ETc until harvest. Results showed that yield in ED and LD was reduced 25 and 15%, respectively, compared to that of the Control, while yield under SDI did not differ significantly from that of the Control and was similar to that of the ED and LD treatments. All the deficit irrigation treatments had some carry-over effects on vine performance due to a significant decrease in shoot fruitfulness and in cluster mass due to smaller berries. Experiment 2 highlights that the response to the minimizing of the radiation load intercepted by the canopy is cultivar-dependent and that decreasing the radiation load in the Mediterranean vineyards could have positive effects on the whole vine's WUE. The effectiveness of the LLR technique seemed to depend on its final impacts on leaf area-to-fruit ratio and vine water status, the cultivar's photosynthetic compensation capacity and the environmental conditions. Therefore, under low vigour vine conditions, severe defoliation might not be advisable for adapting Bobal and Tempranillo to global warming due to the detrimental effects on red wine quality. On the contrary, the results of deficit irrigation and row orientation experiments provided novel insights on WUE as possible techniques to alleviate vineyard water scarcity. Therefore, the field practices studied are effective in adapting Mediterranean viticulture to climate change in terms of water stress. On the other hand, the impacts of the studied techniques in terms of thermal stress alleviation were not fully positive. Hence, further research is needed to determine the possibility of using other field practices, besides LLR, to couple berry sugars and phenolic maturity. / Tècniques de cultiu per adaptar la viticultura mediterrània al canvi climàtic La viticultura mediterrània s'està veient afectada pel canvi climàtic, el que amenaça la tipicitat del vi i, per tant, la sostenibilitat de la vitivinicultura. Els principals factors que es preveu que afecten el cultiu de la vinya són l'escassetat d'aigua, els increments tèrmics i l'augment de la concentració de diòxid de carboni en l'aire, el que influirà en la vinya: i) avançant la seva fenologia, dissociant així la maduració tecnològica i fenòlica del raïm i ii) incrementant les necessitats hídriques de la vinya. Aquest treball pretén avaluar els efectes de diferents tècniques de cultiu per a l'adaptació de la viticultura mediterrània al canvi climàtic. Es van realitzar tres experiments a València (Espanya) estudiant els efectes de: 1) el reg deficitari controlat; 2) l'arquitectura dels sistemes de conducció i 3) el maneig del dosser vegetal. Les principals respostes avaluades van ser l'eficiència en l'ús de l'aigua de la vinya (EUA) i la composició del raïm. L'experiment 1 es va dur a terme durant tres campanyes en una vinya de Moscatell d'Alexandria/161-49C regat per goteig amb l'objectiu de definir l'estratègia de reg més sostenible per al raïm blanc en el llevant espanyol. A tal efecte, es van assajar quatre tractaments: (i) Control, regat al 100% de l'evapotranspiració del cultiu (ETc) durant tota la campanya; (ii) reg deficitari sostingut (SDI), regat al 50% del Contol; (iii) dèficit primerenc (ED), on es va restringir el reg abans del verol, seguit d'un 100% d'ETc; i (iv) dèficit tardà (LD), regat com el Control fins al verol i posteriorment al 25% de l'ETc fins a la verema. La producció en l'ED i el LD es va reduir en un 25 i 15% respectivament en comparació a la del Control, mentre que la producció del SDI no va diferir significativament del Control ni dels tractaments d'ED i LD. Tots els tractaments amb reg deficitari mostraren efectes acumulatius en la productivitat dels ceps, com a conseqüència de la reducció del nombre de raïms per sarment i del tamany del pomell a causa de la menor grandària de la baia. L'experiment 2 posa de manifest que la resposta a la minimització de la radiació interceptada pel dosser vegetal és dependent de la varietat i que reduir la càrrega de radiació en ceps de clima mediterrani podria tindre efectes positius en l'EUA de la vinya. L'efectivitat de la tècnica de LLR pareix dependre dels seus efectes sobre la relació àrea foliar/producció i l'estat hídric de la vinya, de la capacitat fotosintètica compensatòria de la varietat i de les condicions ambientals. Per consegüent, en vinyes de baixa vigorositat, una defoliació severa pot no ser recomanable per a adaptar les varietats Boval i Ull de llebre al calfament global, tenint en compte els efectes perjudicials sobre la qualitat del vi negre. Per contra, els resultats dels experiments de reg deficitari i d'orientació de les files d'espatlera proporcionen noves troballes en l'EUA com a possibles tècniques per pal·liar l'escassetat d'aigua a la vinya. Per tant, les tècniques de camp estudiades resulten eficaces a adaptar la viticultura mediterrània al canvi climàtic pel que fa a l'estrés hídric. No obstant, els seus efectes en termes de mitigació de l'estrés tèrmic no van ser del tot positius. Per tant, cal realitzar més investigacions per a determinar la viabilitat d'emprar altres pràctiques de camp, distintes al LLR, per a equilibrar la maduresa glúcida i fenòlica del raïm. / Buesa Pueyo, I. (2018). Field practices for adapting Mediterranean viticulture to climate change [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107365 / TESIS