Some Biochemical and Ultrastructural Aspects of Peach Fruit Development

Abstract

<jats:p>`Redhaven' peach [<jats:italic>Prunus persica</jats:italic> (L.) Batsch.] fruit growth, expressed as cheek diameter, displayed a double-sigmoid pattern in which four stages were defined (SI, SII, SIII, SIV). Free IAA concentration, as determined by polyclonal antibodies (PcAb) enzyme-linked immunosorbent assay (ELISA), paralleled fruit growth rate, peaking at 30 and 85 days after full bloom (AFB), concurrently with the exponential phases of growth. The highest peroxidase (EC 1.11.1.7) (POD) and IAA oxidase (IAAox) activities occurred during endocarp lignification. The main structural events described were mesocarp cell division within the first 2 weeks AFB and, later, cell enlargement, modifications of the epicarp cells, lignification of the endocarp, differentiation of the chloroplasts, and changes in their starch content. Chemical name used: indole-3-acetic acid (IAA).</jats:p>

Development and metabolism of the fruit and seed of the Japanese plum Ozark premier (Rosaceae)

“…This is consistent with studies of peach, in which the photosynthetic capacity g −1 DW greatly decreases during stage I, and then changes little until the latter stages of ripening when it declines (Pavel and Dejong, 1993b). This decline corresponds to chloroplasts being transformed into chromoplasts (Masia et al, 1992). Rubisco was more abundant in the skin than in the mesocarp throughout development.…”

“…During stage I, the cells of peach endocarp contain prominent vacuoles rich in phenols, which are likely to be lignin precursors. These vacuoles may deposit their contents in the cell wall before their assembly into lignin during stage II (Masia et al, 1992). In the endocarp, there was a large increase in DW during phase I, and this is consistent with lignin precursors being synthesized at this time (Fig.…”

“…It may also allow the export of nitrogenous compounds. In both P. domestica and peach endocarp, the cells are connected by plasmodesmata during lignification (Sterling, 1953;Masia et al, 1992), and this would facilitate this transport. As senescence progresses in barley leaves and cucumber cotyledons, PEPC becomes localized in the vasculature.…”

Development and mapping of peach candidate genes involved in fruit quality and their transferability and potential use in other Rosaceae species

“…In peach, as in other fleshy fruit species, the rapid growth stages I and III are both associated with the enlargement of mesocarp cells involving expansins (Hiwasa et al 2003) and plasma membrane aquaporins (Hu et al 2003). Organic acids are stored in mesocarp cell vacuoles before ripening using tonoplast transporters and proton pumps (Gaxiola et al 2007;Masia et al 1992;Shiratake and Martinoia 2007). The major phenolic compounds in peach are hydroxycinnamic derivatives, mainly chlorogenic acid (5-Ocaffeoyl-quinic acid) and its isomer neochlorogenic acid (3-O-caffeoyl-quinic acid), and flavonoids including the main anthocyanin cyanidin-3-glucoside, flavonol glycosides (quercetin and kaempferol derivatives), and the flavan-3-ol isomers catechin and epicatechin, which can polymerize into proanthocyanidins, known as condensed tannins (Senter and Callahan 1990;Tomas-Barberan et al 2001).…”

The KNOTTED-like genes of peach (Prunus persica L. Batsch) are differentially expressed during drupe growth and the class 1 KNOPE1 contributes to mesocarp development

“…The drupe consists of exo-or epi-carp (skin), mesocarp (pulp or flesh) and endocarp (stone or pit) which hosts one seed (kernel). Pollen tube route is regulated by pistil modifications that include style elongation and obturator degradation [1,3]; after fertilization the ovary wall (pistil portion that holds the ovule) switches into pericarp [4,5], while the outermost style and stigma undergo necrosis [3]. A viable seed is necessary for the proper drupe development at early stages; later on, the link is less tight or absent [6,7].…”