Contribution of Lateral and Primary Leaves to the Development and Quality of 'Kyoho' Grape Berry

Abstract

SummaryThe contribution of lateral and primary leaves to the growth and quality of 'Kyoho' (Vitis vinifera × V. labrusca) berries was investigated. The total leaf area on each bearing shoot was adjusted to ca. 1500 cm2 by removing primary or lateral leaves at veraison so that the percentage of lateral leaf area (LL) beyond or distal to the cluster was : ca. 100 (100 -LL), 70 (70 -LL), 30 (30 -LL), and 0 (0 -LL) of the ca. 1000 cm2.The net photosynthetic rate (Pn) of the primary and lateral leaves on treated and intact shoots were determined.1. The berries on 100-and 70 -LL shoots ripened faster than they did on 30-and 0 -LL shoots. Berries on 100-and 70 -LL shoots accumulated total soluble solids (TSS) and anthocyanin faster than they did on 30-and 0 -LL shoots. Contrarily, titratable acidity of the berries on 100-and 70 -LL shoots decreased more rapidly than they did on 30-and 0 -LL shoots.2. During the ripening stage of the berry, the Pn of lateral leaves was faster than that of primary leaves. The Pn of basal primary leaves was significantly slower which may be responsible for the retarded ripening of berries on 0 -LL shoot.3. No significant difference was found in the leaf structure or the mineral nutrient content between primary and lateral leaves when measured before the veraison.

Excessive nitrogen supply and shoot trimming can impair colour development in Pinot Noir grapes and wine

“…According to Poni and Intrieri (1996) topping should be calibrated to promote lateral shoots which become mature around veraison. Younger leaves on these laterals are more active photosynthetically than older main leaves and enhance fruit quality by exporting assimilates to the ripening grapes (Hirano et al 1994, Koblet et al 1996.…”

Influence of summer management practices and date of harvesting on organic acids concentration and sugar concentration in grapes of Vitis vinifera L., cv. Riesling

“…Partial defoliation of shoots enables exposure of berries to enrich them with photosyntethates thanks to the enhanced photosynthetic activity of the remainder of leaves (Hunter, Visser 1988), which corresponds with the best results obtained on treatments III and IV, where the lateral shoots were not removed, but just hedged at leaf 2. Hirano et al (1994) proved that lateral foliage fastens the photosynthetic rate compared with primary foliage, which results in increased accumulation of sugar. In addition, Vasconcelos and Castagnoli (2000) confirmed that lateral shoots accelerate fruit ripening and suggest that this technique can improve fruit composition in short-season regions.…”