PERFORMANCE OF ZINFANDEL AND PRIMITIVO CLONES IN A WARM CLIMATE

Four clones of Zinfandel and one clone of Primitivo, all certified vir us-tested, were compared in a warm, Region V, climate over a five-year period. Few significant differences were found among Zinfandel clones ; however, Primitive differed substantially from Zinfandel. Despite ha ving significantly more clusters per vine, Primitivo had 15% lower yie ld due both to 14% fewer berries per cluster and 11% smaller berries. Primitivo's 10% heavier pruning weight and advanced maturity (about 1 degrees Brix) could both be accounted for by its lower yield per vine.