Effects of mechanical Pre-Bloom Defoliation on Cordon de Royat Sangiovese ( Vitis vinifera L.)

Recent trials on Sangiovese vines have shown that hand defoliation of shoot basal leaves at pre-bloom is effective in reducing fruit-set and yield, leading to better grape quality composition. The present work was performed to assess if similar outcomes could be replicated by a more economically viable mechanical approach, which appears to be extremely attractive in cultivars such as Sangiovese, marked by high or very high yield attitude and heavy, fairly compact clusters, quite sensitive to rot. The pre-bloom HD of shoot basal leaves confirmed its positive effect in cropping control and improving grape composition, leading to better grape quality composition. The pre-bloom MD of the basal part of the shoots maintained most of the advantages linked to the HD, although only half of the leaf area removed by hand was removed by the machine.