Quantitative Flow of Water, Sugars and Organic Acids in Individual Grape Fruits During Maturity

Rezk Shahood*(1) and Charles Romieu(2)

(1). Agricultural Research in Latakia, General Commission for Scientific Agricultural Research GCSAR, Damascus, Syria.

(2). INRA, Montpellier, France.

(*Corresponding author: Dr. Rezk Shahood. E-Mail: rezk.sh@hotmail.com).

Received: 10/05/2019                                Accepted: 04/06/2019

Abstract

The study was conducted in order to compare the development of the individual grape fruit with those samples represented by the average number of asynchronous fruits in their development, so the flows of water, sugars and malic acid were determined in the individual fruits and their timing of development. The varieties of Pinot meunier and Syrah were used in the experimental SubAgro field, and the dwarf variety ML1 was used under laboratory-controlled conditions in Montpellier, France, during 2014/2015 season. The study was conducted using a single non-synchronized fruit (the ripening date not determined), and single fruits with defined ripening dates. The results showed non synchronicity at the beginning of sucrose storage, which is the main reason of fruits differentiation. Sugars import activity through the phloem started from softening and lasted for 26 days only. Sugar imports stopped at a concentration of 0.9 M, then sugar concentration is determined by shriveling in volume as a result of transpiration and evaporation.  Growth enhanced during the first six days after ripening, then resumed. Malic acid became the major respiratory element during early ripening, where its contribution decreased rapidly and stopped in two weeks only.

Key words:  Grapes, Fruits development, Metabolic flux, Sugars, Malic acid.

Full paper in Arabic: PDF