ResumoAs características físicas e químicas dos frutos variam durante o período de pós-colheita, e essa variação depende, entre outros fatores, das condições meteorológicas durante o desenvolvimento dos frutos. Este trabalho objetivou avaliar as alterações nas características físicas e químicas de oito cultivares de pêssego em duas safras. As cultivares Campinas 1, Coral, Maciel, Marli, Premier, Régis, Rei da Conserva e Tropic Beauty foram plantadas sobre o porta-enxerto Okinawa no pomar experimental da Universidade Federal de Viçosa (UFV), Viçosa-MG em 2008 e avaliadas quanto às características massa de fruto, cor da epiderme, firmeza, teor de sólidos solúveis, acidez titulável, teor de ácido ascórbico e carotenoides totais. O experimento foi conduzido durante as safras de 2011 e 2012, em delineamento inteiramente casualizado, com oito tratamentos (cultivares), três repetições e 10 frutos por parcela. Houve diferenças entre as características avaliadas nas duas safras, sendo as maiores variações observadas na firmeza da polpa e nos teores de ácido ascórbico e de carotenóides totais. As cultivares Maciel e Marli produzem frutos com maiores valores de massa, Tropic Beauty com maior firmeza e Rei da Conserva, Coral e Marli com maiores teores de sólidos solúveis. A cultivar Rei da Conserva se destacou em relação à maioria das características em ambas as safras. A tonalidade amarela no pêssego está associada com carotenóides totais.Palavras-chave: Adaptação, amadurecimento, Prunus persica (L.) Batsch, qualidade de fruto Postharvest quality of eight peaches cultivars AbstractThe fruit physical and chemical characteristics can vary during the maturation period and this variation depends, among other factors, on the weather conditions during fruit development. This study aimed to evaluate the changes in physical and chemical characteristics of eight peach cultivars during two seasons. The cultivars Campinas 1, Coral, Maciel, Marli, Premier, Regis, Rei da Conserva and Tropic Beauty were planted on Okinawa rootstock at the experimental orchard of the Federal University of Viçosa (UFV), Viçosa-MG, Brazil, in 2008 and the following characteristics were evaluated: fruit weight, skin color, firmness, soluble solids, titratable acidity, ascorbic acid and total carotenoids. The experiment was conducted during 2011 and 2012 growing seasons in a completely randomized design with eight treatments (cultivars), three repetitions and 10 fruits per plot. There were differences between the variables for the two seasons, with the largest variations observed for firmness, ascorbic acid and total carotenoids. Cultivars Maciel and Marli produced fruit with higher mass, Tropic Beauty with greater firmness and Rei da Conserva, Coral and Marli with higher soluble solids contents. The cultivar Rei da Conserva presented higher values for most of the evaluated variables in both seasons. The yellow color, evaluated by the hue angle, is associated with total carotenoids content in peaches.

Information on adaptability and stability of fruit production in different environments or years is crucial to increasing agricultural production potential. Therefore, the objective of this study was to evaluate whether there is interaction between cultivars and years, as well as to assess the stability of peach and nectarine cultivars regarding fruit fresh mass, SS/TA ratio, and cycle length in Viçosa -MG, Brazil. The characteristics fruit fresh mass (FM), soluble solids/titratable acidity ratio (SS/TA), and cycle length (CL) were evaluated in 28 cultivars of peach and two cultivars of nectarine from the orchard of the Universidade Federal de Viçosa, in 2011, 2012, and 2013. The methods used to determine the phenotypic stability across time were Eberhart & Russell (1966) and the Traditional. The interaction cultivars x years was significant for all traits. Cultivar ‘Josefina’ showed broad adaptability for SS/TA ratio, and cultivars ‘Flordaprince’ and ‘Tropical’ for cycle length. For favorable environments, the cultivars ‘Capdebosq’ and ‘Maciel’ are indicated regarding the characteristic fruit mass, and ‘Coral’ and ‘Talismã’ for SS/TA ratio. ‘Rubimel’ was adaptable to unfavorable environments regarding fruit mass.

A avaliação da qualidade física e química de frutos de pessegueiro destinados ao consumo in natura varia entre safras. Essa variação depende, dentre outros fatores, das condições do local de cultivo. O objetivo deste trabalho foi avaliar a qualidade física e química de frutos de dezesseis cultivares de pessegueiro durante três safras em Viçosa-MG. As cultivares Aurora 2, Baronesa, Biuti, Colibri, Coral, Cristal, Delicioso Precoce, Flor da Prince, Joia 4, Lake City, Marli, Pérola de Iataquera, Rubimel, Talismã, Tropical e Tropic Beauty foram enxertadas sobre o porta-enxerto Okinawa no pomar experimental da Universidade Federal de Viçosa, em Viçosa-MG, no ano de 2008, e avaliadas quanto às características cor da casca (b* e h°), cor da polpa (b* e h°), massa do fruto (g), diâmetro polar (mm), diâmetro equatorial (mm), diâmetro sutural (mm), frmeza da polpa (N), teor de sólidos solúveis (oBrix), vitamina C (mg/100g), acidez titulável (% de ácido málico), carotenoides (mg/100g) e ratio (relação teor de sólidos solúveis e acidez titulável) durante as safras de 2011, 2012 e 2013. O experimento foi conduzido em delineamento inteiramente causalizado, com dezesseis tratamentos, três repetições e 10 frutos por parcela. Houve diferenças entre as características avaliadas nas três safras, sendo que a cultivar Floridaprince apresentou coloração mais intensa da epiderme bem como maiores teores de vitamina C.

Abstract

This study aimed to evaluate the relationship between fruit traits and their direct and indirect effects on the content of ascorbic acid and carotenoids in peaches and nectarines. The traits fruit mass (FM); equatorial diameter (ED); suture diameter (SD); polar diameter (PD); pulp firmness (FIR); soluble solids (SS); titratable acidity (TA); SS/TA ratio; contents of ascorbic acid (AA) and carotenoids (CT); and skin and pulp color were evaluated in 28 peach cultivars, and two nectarine cultivars. The phenotypic correlation coefficients were estimated (rf), and after multicollinearity diagnosis, unfolding was carried out in direct and indirect effects of the explanatory variables in the response variable by using path analysis. The strongest correlations were found between FM, SD, ED, and PD, and between carotenoid content and °h pulp. The traits considered in the path diagrams are not the main determinants of the ascorbic acid content. The yellow color of the pulp has the potential for indirect selection for carotenoid content.