Management aspects and blueberry cultivars: quality and productivity

Este estudo teve como objetivo avaliar o crescimento, a produ????o e a qualidade das frutas de mirtileiros, sob diferentes formas de manejo de plantas. Os fatores avaliados foram: doses de nitrog??nio, doses de enxofre e intensidades de poda. Al??m disso, foi avaliado, por meio de competi????o de cultivares, aquelas que apresentavam melhor qualidade de frutos, nas condi????es edafoclim??ticas de Torino, norte da It??lia. Para isso foram realizados quatro experimentos. (1) influ??ncia de doses de nitrog??nio, utilizando como fonte o sulfato de am??nio (NH4)2SO4 com 21% de N2 e 23% de enxofre; (2) influ??ncia de doses de enxofre em gramas por m3 de substrato; (3) avalia????o da intensidade de poda; e (4) avalia????o de cultivares Aurora, Berkeley, Bluecrop, Gulfcoast, Jewel, Legacy, Liberty, Millenia, Misty, O'Neal, Ozarkblue, Palmetto,Primadonna, Sebring, Snowchaser, Southernbelle, Springhigh, Springwide, StarIt??lia, durante o ano de (2011/2012). Em todos os experimentos as vari??veisresposta foram produ????o e qualidade de frutos, alcan??ada por meio de an??lises f??sico-qu??micas e presen??a de fitoqu??micos nos frutos. Nos dois primeiros experimentos foram avaliados, ainda, os mineirais presentes nos frutos. Conclui-se que: as doses de nitrog??nio aplicadas no solo n??o alteram produtividade e crescimento de plantas. Dentre as caracter??sticas f??sicoqu??micas dos frutos, apenas acidez total titul??vel ?? alterada pelas doses de nitrog??nio. Antocianinas, compostos fen??licos e atividade antioxidante, s??o influenciadas pelas doses de nitrog??nio. A produ????o de frutos e o crescimento de plantas, n??o foram alterados com as aplica????es de enxofre, no primeiro ano de produ????o. Por outro lado, compostos fen??licos respondem de forma quadr??tica e a acidez total diminuiu, influenciada pelas aplica????es de enxofre. Quanto ?? an??lises das cultivares na Italia, Aurora, Draper, Bekeley, Bluecrop, Bonifacy, Brigitta, Legacy, Liberty, podem ser consideradas tardias, nas condi????es de Torino. A cultivar O'Neal possui a colheita mais concentrada. A cultivar Jewel ?? uma das melhores com rela????o ?? composi????o f??sico-qu??mica, mas deve ser melhor estudada com rela????o ?? adaptabilidade. Legacy e Palmetto apresentam elevados teores de polifen??is, com frutos de bom tamanho e apar??ncia.The objective of this study was to evaluate the growth, production and fruit quality of blueberry under different plant management. The parameters evaluated in Southern Brasil, were: nitrogen and sulfur dosages and pruning intensity. It was also corrield out a cultivar test to choose, the ones with better fruit quality in environmental conditions of Turin, northern Italy. Four experiments were conducted to reach the objectives: (1) the nitrogen influence, using ammonium sulfate (NH4)2SO4 with 21% N2 and 23% sulfur as a nitrogen source, (2) influence of sulfur dosages (in grams per m3 of pots), (3) evaluation of intensity of pruning, and (4) evaluation of cultivars Aurora, Berkeley, Bluecrop, Bonifacy, Brigittablue, Draper, Duke, Emerald, group 'Northen highbush', and Gulfcoast, Jewel, Legacy, Liberty, Millenia, Misty, The ' Neal, Ozarkblue, Palmetto, Primadonna, Sebring, Snowchaser, SouthernBelle, Springhigh, Springwide, Star Group 'southern highbush'. The last experiment was conducted in Torino, Italy, during the 2011/2012 growth season. In all experiments the variables analyzed were production and fruit quality, achieved through physical and chemical analysis, and the presence of phytochemicals in fruits. In the first two experiments, were also evaluated the minerals present in fruits. The conclusions were: the nitrogen applied on soil does not alter plant growth and productivity. Among the physico-chemical characteristics of fruits, only total acidity is changed according to the nitrogen dosages. Anthocyanins, phenolic compounds and antioxidant activity are influenced by nitrogen. Fruit yield and plant growth were not altered with the sulfur application, in the first production year. Moreover, phenolic compounds exhibit quadratic response and the total acidity decreased influenced by the sulfur applications. In relation to the analysis of cultivars in Italy, Aurora, Draper, Bekeley, Bluecrop, Bonifacy, Brigitta, Legacy, Liberty, may be considered late in the conditions of Torino. The cultivar O'Neal has the most concentrated harvest. The cultivar Jewel is one of the best in respect to physico-chemical composition, but should be further investigated in respect to adaptability. Legacy and Palmetto have high levels of polyphenols, with good fruit size and appearance