No Brasil, as cultivares de mirtileiro, exploradas economicamente, foram introduzidas de outros países e, sendo assim, selecionadas em outras condições edafoclimáticas, podendo apresentar limitações para seu cultivo. Visando à obtenção de plantas superiores mais adaptadas para as condições brasileiras, realizou-se a seleção em três populações de mirtileiro de polinização aberta com o objetivo de obter progênies superiores. O material vegetal utilizado constituiu-se de 3.554 plantas, provenientes de sementes das cultivares Bluegem (1.212 plantas), Bluebelle (1.439 plantas) e Powderblue (903 plantas). O experimento foi conduzido em área previamente adubada, conforme análise de solo, em espaçamento de 30 x 30 cm, com sistema de irrigação por aspersäo. A seleção nas plantas das três populações foi realizada em três etapas (2007/2008, 2008/2009 e 2010/2011). No primeiro ciclo, realizou-se a seleção negativa, eliminando-se as plantas indesejáveis; no segundo, foi realizada a seleção positiva, quando foram selecionadas 20 plantas de cada uma das populações. Como critério de seleção, nos dois primeiros ciclos, foram usados os seguintes caracteres: vigor da planta, produção, estado fitossanitário, início de produção, presença de pruína na epiderme, tamanho e sabor do fruto. Ao final do segundo ciclo, as 20 plantas pré-selecionadas de cada população foram avaliadas, por um período de dois anos (2009/2010 e 2010/2011), registrando-se a produtividade das plantas e as variáveis químicas dos frutos. Com base nos resultados obtidos, pode-se concluir que 10 genótipos (BG5, BG2, BG3, BG6, PW3, PW5, PW1, BB10, BB5 e BB2) têm potencial para dar-se continuidade ao processo de seleção, pois apresentam bom desenvolvimento vegetativo, frutos de boa qualidade e de tamanho adequado ao mercado consumidor.
Blueberry cultivars economically grown in Brazil were introduced from other countries, in which they were selected according different edaphoclimatic conditions and so it might impose some cultivation limitation in Brazil. In order to obtain superior progenies better adapted to Brazilian conditions, it was performed plant selection in three free polinization blueberry populations. The plant material consisted of 3,554 plants obtained from seeds from the cultivars Bluegem (1,212 plants), Bluebelle (1,439 plants) and Powderblue (903 plants). The experiment was performed in an area previously fertilized according to soil analysis, in a spacing of 30 x 30 cm, with sprinkler irrigation system. The selection was performed during three growing seasons (2007/08, 2008/09 and 2010/11). In the first growing season it was made a negative selection, eliminating the undesirable plants; in the second, a positive selection was performed, where 20 plants were selected from each of the populations; and the third, also by positive selection, where ten plants were selected within each set of 20 plants previously selected in the second step. As the selection criteria, it was used the following characteristics for the first two growing seasons: plant vigor, production, plant health, early production, presence of bloom, fruit size and fruit flavor, the latter assessed by two trained individuals. At the end of the second growing season, the pre-selected 20 plants of each population were evaluated for a period of two years (2009/10 and 2010/11), recording productive parameters of these plants and chemical parameters of the fruits. The subjective consideration of these outcomes was an additional criterion used for the selection of the third growing season plants. It was noticed that the genotypes of the three cultivars of this study show yield and fruit size suitable to the market. Moreover, genotypes derived from the cultivars Bluegem and Powderblue have better sugar/acidity relationship. Based on the results obtained, it can be concluded that the genotypes BG5, BG2, BG3, BG6, PW3, PW5, PW1, BB10, BB2 and BB5 have the potential to continue the selection process, since they have good vegetative growth, fruit good quality and size appropriate to the consumer market.
