RT Journal Article SR Electronic T1 Growth and Fruiting of Container-Grown Seyval blanc Grapevines Modified by Changes in Crop Level, Leaf Number and Position, and Light Exposure JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 191 OP 199 DO 10.5344/ajev.1992.43.2.191 VO 43 IS 2 A1 Martin L. Kaps A1 Garth A. Cahoon YR 1992 UL http://www.ajevonline.org/content/43/2/191.abstract AB Container-grown Seyval blanc grapevines were subjected to varying crop and leaf levels. In adjusting leaf number, approximately 8 to 10 cm2 leaf area per gram of fruit weight gave maximum total fruit weight, average berry weight, and °Brix. Leaf, stem, and root dry weights increased through 15 cm2/g, the maximum leaf area/ fruit weight measured. Titratable acidity (TA) and pH were not consistently changed. A reduction in leaf area affected vegetative growth first, °Brix next, and fruit weight last. In modifying leaf position in relation to a basal cluster, total fruit weight, °Brix, TA, pH, and vegetative growth were highest on plants with leaves distal to the clusters. These results were likely due to good exposure and greater area of leaves on these distal nodes. Regrowth from an apical node advanced fruit maturity and increased vegetative growth rather than compete with it. Shading lower leaves and the cluster (versus removing lower leaves) did not affect total fruit and average berry weights. Root dry weight was greater where leaves were shaded.