Peach

El área foliar es un parámetro ampliamente usado en estudios de ecofisiología de cultivos, debido a que la relación existente entre el área foliar y la producción de fruta es bastante estrecha. Para su determinación se utilizan diferentes métodos ya sean destructivos, no destructivos o indirectos. La estimación del área foliar es una importante observación biométrica que debe hacerse con el propósito de comparar el comportamiento de los vegetales en función de diferentes tratamientos. El objetivo del estudio fue la determinación y validación de las funciones de regresión más acertadas para la estimación no destructiva del área foliar en algunos cultivares de duraznero y ciruelo. En este trabajo se calcularon funciones matemáticas para estimar el área foliar en los cultivares Gold Fruly, Ecuatoriano, Methley y Horvin, de ciruelo, y en los cultivares Dorado, Rubidoux, Diamante y Rey Negro, de duraznero. Las hojas se colectaron de árboles cultivados en Paipa, Colombia. Se seleccionó una función de regresión para cada cultivar y se realizó su validación comparando datos de área foliar estimados con las funciones matemáticas y datos medidos con el medidor de área foliar. Se tomó como variable independiente (X) de la función, el producto del largo por el ancho de la hoja. En todos los casos el coeficiente de correlación de Pearson presentó valores superiores a 0,9, señalando la estrecha relación entre los datos estimados y los observados. Con el uso de estas funciones, es posible estimar de manera no destructiva, el área
foliar en los cultivares de duraznero y ciruelo involucrados en el estudio.

'Ruby Rich' is a yellow-flesh peach cultivar that ripens during the last week of May and the first of June. This fruit is characterized by distinct colour and size, which make it highly appreciated by consumers, particularly, in the local markets. However, is known about 'Ruby Rich' minimal processing physiology. The aim of this study was to investigate the effect of passive atmosphere, during 12 d, on shelf-life and quality of fresh cut peach fruit, at different ripening stages. 'Ruby Rich' peach fruits were picked at mature-green stage (MG) (55.0 ± 0.5 N), and ripe stage (RP) (35.7 ± 0.7 N) determined by flesh firmness. Fruits were washed, peeled, sliced and stored for 0, 3, 5, 7 and 12 days after cut, six replications were used for each storage time. Scores of appearance and firmness, weight, colour, respiration rate, soluble solids total, ascorbic acid and phenols were observed. Significant differences occurred on MG treatment in terms of visual quality, flesh firmness, polyphenols and ascorbic acid. Results shows that peach slices (RP) maintain the shelf life condition for 5 d. at 5 °C with the best results in terms of solid soluble content and flavour.

The peach x almond hybrid GF 677 is a vigorous rootstock widely used for peach across Italy. However, despite its high production and adaptation to various soil and environmental conditions, this rootstock may induce excessive vigor and decrease fruit quality. Today, modern peach industry demands rootstocks which combine: (a) reduced vigor, suitable for high density systems, facilitating canopy management (e.g. mechanization of pruning, thinning and harvest); and (b) high yield and fruit quality.
In this study, the productive evaluation of peach trees grafted on six rootstocks of different vigor from three different locations, Castelvetrano (Sicily), Forlì (Emilia-Romagna) and Cesena (Emilia-Romagna) is reported. In Castelvetrano and Cesena, rootstocks GF677 (Prunus persica x P. dulcis) and Garnem (P. dulcis x P. persica), Adesoto (P. insititia), Rootpac-20 (P. besseyi x P. cerasifera), Rootpac-40 [(P. persica x P. persica) x (P. dulcis x P. persica)], and Rootpac-90 [(P. persica x P. davidiana) x (P. dulcis x P. persica)] were grafted with the nectarine cultivar Big Top. In Forlì, the same rootstocks were grafted with the peach cultivar Rome Star. Yield, number of fruits, trunk cross-sectional area (TCSA), average fruit weight, flesh firmness, soluble solids content (SSC) and titratable acidity (TA) were determined at the third leaf (2015).
In all experimental sites, in both ‘Big Top’ and ‘Rome Star’, GF 677, Garnem and RP90 induced the highest vigor, while RP40 and RP20 the least. In Emilia-Romagna, yield efficiency was highest in the most vigorous trees, with the only exception of RP40, which combined a size-controlling effect with high yield efficiency and large fruit size. RP40 induced biggest fruit size in all experimental sites and also led to the highest yield and yield efficiency in Sicily. In addition, Adesoto advanced fruit maturation in Sicily.
Productive and qualitative data will be collected and analyzed in the following years in order to validate the results of 2015

Peach (Prunus persica L. Batsch) trees need to be thinned in order to guarantee yield of fruits of marketable size and a sufficient return to bloom in the following season. In this fruit crop, however, thinning is often complicated by several endogenous as well as exogenous factors, such as genotype, orchard structure, environmental conditions and agronomic management, and the current thinning methods (manual, mechanical or chemical), taken singularly, present more disadvantages than advantages. Therefore, the only possible option is currently represented by the adoption of a "thinning strategy", consisting in subsequent interventions at different phenological stages, to finely tune the final fruit load along its physiological evolution. Such strategies must also consider the ongoing climate changes, which further complicates the thinning interventions also due to the lack of Decision Support Systems (DSSs), and the current trends of the global market. The present review takes a picture of the current situation of peach thinning, with a particular focus on the current development of new chemical thinners, and its future perspectives. Some general remarks are made considering the evolution of the global market and the obstacles found in peach research in some of the most traditional peach areas of the world.

Sicilian white flesh peach fruits ecotypes are characterized by a persistent aroma and excellent fl avor that is highly appreciated by consumers. Nevertheless, they reach only regional markets, because of fruit sensitivity to decay and the poor information about their postharvest physiology and shelf-life. In this trial, we studied quality changes during postharvest life of non-melting white-fl esh peach ecotypes 'Tudia', 'Bella di Bivona' and the cultivar 'Daniela'. Fruits were collected at commercial ripening: a fi rst group was submitted to analytical evaluations and another one was stored (2°C, 90% RH) for 32 days. During this storage period, fruits were submitted to four shelf-life periods at ambient temperature (22°C) for 6 days and analyzed every 3 th and 6 th day. In the period of shelf-life, during storage of fruit at 2°C, we ascertained that Bella di Bivona and Daniela have a shelf-life of 12–14 days while 'Tudia' could reach up to 25–32 days. Flesh fi rmness and chilling injuries trends, during shelf-life, allowed to discover 'Tudia' as the variety which presents the best performance after storage at low temperatures for long periods.