Impact of bud load on the yield components and composition of the berry of Chardonnay on spur cordon in Istria, Croatia

Abstract

The investigation was conducted from 2009 to 2012. on cv. Chardonnay in the productive vineyard. Training system was Istrian spur cordon, an unilateral spur cordon with upward positioned shoots, which characteristics were investigated in the agroecological conditions of Istria (Croatia), in a continuity of ten years.

Two bud loads of 16 buds and two bud loads of 32 buds per vine were investigated in this study, with a total of four treatments. Lower bud loads were represented with vines having eight arms with one spur containing two buds or two spurs containing one bud. Higher bud loads were represented with vines having eight arms with two spurs containing two buds or four spurs containing one bud. Each treatment had three repetitions of five vines. The experimental design was randomized blocks design.

Yield, number of bunches per vine, cluster weight, sugar content and titratable acidity in must were mostly different among different vegetation seasons.

Within the same year yield and the number of clusters per vine were mostly higher on vines with a bud load of 32 buds. Bud fruitfulness and cluster weight were generally higher on vines with a bud load of 16 buds. Sugar content, titratable acidity and pH value of must varied vary slightly among different treatments.

Based on the results of this four years experiment it can be concluded that the Istrian spur cordon, combining different bud loads, can be successfully applied to Chardonnay in Istria in the production of targeted grape quality.