Contributo para o estudo do medronheiro (Arbutus unedo L.): caracterização morfológica de clones e fisiologia pós-colheita do fruto

Mestrado em Engenharia Agronómica - Instituto Superior de AgronomiaThis study had two objectives that aim to contribute to a greater knowledge of Arbutus unedo. The first objective was to characterize morphologically different clones installed in a commercial orchard in Oleiros, Castelo Branco, in order to detect the morphological differences between them, as well as to monitor the vegetative cycle. The second objective was to study the physiological behavior of the fruit in the post-harvest period, in order to better assess the evolution of the maturation. The clones showed significant differences in the cross sectional area of the trunk and in the canopy height. Leaves showed significant differences in the length (L), width (W), L/W ratio, petiole length and leaf thickness. The percentage of trees with fruits, the average number of inflorescences and the number of fruits and shoots per inflorescence were significantly different. Fruits at different stages of maturity showed significant differences in firmness, L, hue and saturation. Except for the green fruits, all states of maturation showed an increase in the soluble solids content and pH while titratable acidity decreased. It was not found a marked evolution of vitamin C and total phenolic contents in the postharvest period. Considering the above, as well as the rate of respiration and ethylene production rate of the fruits, we suggest that although it is not a typical climacteric fruit, its postharvest behavior is closer to the climacteric fruits than of the nonclimateric fruits.Este trabalho teve o Apoio da Fundação para a Ciência e Tecnologia através do Projecto PTDC/AGR-FOR/3746/2012 – “Arbutus unedo plants and products quality improvement for the agro-forestry sector” e do Programa de Desenvolvimento Rural - PRODER, medida 4.1, Cooperação para a Inovação, Ref.ª 43748 – “O Medronho - Conversão da planta silvestre numa espécie fruteira rentável”