Acceleration of veraison and enhancement of berry quality of "crimson" grapes bypreharvest treatments with lysophosphatidylethanolamine, protone and magnesium

الملخص EN

This study was conducted during the two successive seasons 2015 and 2016 on "Crimson" grapevine grown in a private orchard at Nobariya district, Beheira governorate, Egypt.

The vines were under the standard cultural practices, uniform, healthy and free of visible disorders.

The vines were sprayed with one of the following treatments that included water (control), lysophosphatidylethanolamine (lisophos) at 200 ppm and 400 ppm, lisophos at 200 ppm + MgNo3 at 1% (w/v), lisophos at 400 ppm + MgNo3 at 1% (w/v), ABA (ProTone as the trade name) at 100 ppm and 400 ppm, the combination of ProTone at 100 ppm + MgNo3 at 1% (w/v), at 200 ppm + MgNo3 at 1% (w/v), in addition to MgNo3 alone at 1% (w/v).

The non-ionic surfactant Tween 80 was added to all treatments at 0.05% (v/v).

Four vines per treatment were sprayed to the run off point by a hand sprayer on Aug.

1st and 5th during the two seasons, respectively.

First sampling was done ten days after spray while the second sampling followed the first one by ten more days.

The data provided evidences about the possibility of accelerating the veraison stage in a consistent manner especially in the second season.

As shown by the color initiation at the first sample after ten days of spray and at harvest especially carotene and anthocyanin and the reduction of chlorophylls a and b in particular with the combinations of lisophos at 400 ppm plus MgNo3 at 1% as well as ProTone at 200 ppm plus MgNo3 at the same above concentration in addition to the significant increase in the TSS to acidity ratio at thefirst picking in both seasons.

Moreover, juice acidity and tannins content were significantly reduced with the above two formulations and with the individual treatment of many other treatments at the first picking and at the final harvest such as lisophos at 200 ppm and 400 ppm and ProTone at 100 or 200 ppm.

Meanwhile, berry size did not significantly vary among used treatments at the first sampling time but increased significantly by many treatments at the second picking.

The main conclusion of this study can recommend using the formulation containing lisophos at 400 ppm plus magnesium nitrate at 1% (w/v) as well as ProTone at 200 ppm plus MgNo3 at 1% to accelerate veraison and enhance the berries quality of "Crimson" grapevine under field conditions.