Effects of pre-bloom leaf removal on growth of berry tissues and must composition in two red Vitis vinifera L. cultivars

摘要: Background and Aims:  Little work has been conducted on the effects that summer pruning operations have relative growth of grapevine berry parts. Our paper studies whether pre-bloom leaf removal is able to modify proportions seed, skin flesh in ripe grapevines berries related must composition. Methods Results:  Pre-bloom defoliation (D) first six basal leaves main shoots was applied field-grown cvs Barbera Lambrusco salamino (Vitis vinifera L.) Italy's Po Valley compared with non-defoliated controls. D showed reduced fruitset, hence yield per shoot, concurrently improved soluble solids total anthocyanins both cultivars as a likely result increased leaf-to-fruit ratio (+3.4 cm2/g +5.2 cm2/g for Lambrusco, respectively) mass (from 6.0 9.0% from 8.1 10.4% Lambrusco). In cultivars, seed were highly correlated changes generally not size. Conclusions:  These results indicate size se primary factor determining final grape composition, which instead seems depend upon factors differentially affecting various components. Significance Study:  induced consistent, site cultivar-independent increase suggesting this effect being strongly physiologically regulated.