Fruit Distribution and Early Thinning Intensity Influence Fruit Quality and Productivity of Peach and Nectarine Trees

Abstract

<jats:p>Peach [<jats:italic>Prunus persica</jats:italic> (L.) Batsch, Peach Group] tree productivity is improved if trees are thinned early, either in full bloom or when the fruit is recently set. Chemical thinning reduces the high cost of manual thinning and distributes the fruit irregularly on the shoots. The effect is similar to a late spring frost that mostly affects early flower buds on the tip of the shoot. To simulate frost damage (or chemical thinning) and evaluate the effect of fruit distribution on production, fruit growth of several peach cultivars—'Catherine', `Baby Gold 6', `Baby Gold 7', `O'Henry', `Sudanell' and `Miraflores'—and the nectarine [<jats:italic>Prunus persica</jats:italic> (L.) Batsch, Nectarine Group] `Queen Giant' was studied in the central Ebro Valley (Spain) in 1999 and 2000. The factors investigated were the intensity of thinning and fruit distribution on the shoot (concentrated in the basal area or uniformly placed). The treatments were performed at 30 days after full bloom in 1999 and at bloom in 2000. For `Baby Gold 6' and `Miraflores' and when fruit load was high after thinning (over four fruit per shoot), a high concentration of fruit on the basal portion of the shoot had a negative influence on final yield and fruit size. The intensity of thinning (or simulated frost) greatly affected fruit diameter but was also strongly related to cultivar, tree size, and length of shoots. Thus, relationships between thinning intensity and fruit diameter varied, even among trees of the same cultivar.</jats:p>

Thinning flat peaches with ethephon and its effect on endogenous ethylene production and fruit quality

“…Some factors such as cultivar, weather conditions, or application time have been reported to affect the efficacy of ethephon in fruit thinning and/or the appearance of side effects. (Costa and Vizzotto, 2000;Drogoudi et al, 2009;Jiménez and Díaz, 2002;Meland and Kaiser, 2016;Webster and Spencer, 2000). All these aspects could be related with endogenous ethylene biosynthesis.…”

Gestión de la calidad del fruto mediante prácticas culturales y aplicación de un modelo fisiológico en melocotonero

“…Regarding to the mid-season variety ("Catherine") (Publication 3), the effects of previously mentioned factors (water stress and fruit position within the canopy) on fruit quality, were evaluated by analyzing the evolution and sugar content within these fruits. In this sense, similar studies have been conducted in peach, where the fruit quality analysis carried out are mainly focused on attributes such as ground colour or soluble solids content (Corelli-Grappadelli et al, 1991;Miranda-Jiménez and Royo Díaz, 2002). However, only a few of them analyze in detail the sugars content and time evolution (Génard and Bruchou, 1992).…”