Five clonal trials were harvested in 1991, two Chardonnay, two Cabernet Sauvignon, and 1 combination of Zinfandel, Primitivo and Sangiovese. Clones were assessed for yield components and fruit maturity indices. Small-lot wines were made from only one trial (Jaeger Chardonnay) because of a shortfall of funds. The cane-pruned Jaeger Chardonnay clonal trial yielded less on average than the cordon-spur-pruned Beringer trial, although the trends bore some similarities. As in the past, clones 4 and 5 were among the highest yielding in both trials. Clone 14 at Jaeger and clones 6, 14 and 15 at Beringer were intermediate in yield. As has been the historical case, clone 16 yielded one-half to one-third of the highest yielding clones. It is interesting that the yield-pruning ratios varied from 1.5 to 7.8 at Jaeger and from 2.8 to 13.3 at Beringer. There has been a consistent trend for heavier pruning weights for clone 6 and 15, intermediate pruning weights for clones 4, 5, and 16 and low pruning weights for clone 14. The Cabernet clonal trial at Mondavi Woodbridge is showing that the highest yielding clones are 8 and 21, with clones 2, 4, 5, and 10 as intermediate and clone 6 as the lowest. The difference between the high and intermediate yielding clones is less than in past years. For the Zinfandel-Primitivo-Sangiovese trial, the 10-vine plots were split into thinned and not-thinned groups in 1991. Thinning of course reduced yield but did not result in larger vine size at dormant pruning in 1991-2. There were few differences among the Zinfandel selections. In many respects, Primitivo yield components were very similar to Zinfandel, although the formere seemed to ripen sooner. Sangiovese clones ripened sooner than either Zinfandel or Primitivo. Sangiovese 3 had fewer berries/cluster than Sangiovese 2, althoug the berries were somewhat heavier. Over the past two to three years additional trials have been established in Napa (Merlot, Cabernet Sauvignon), Sonoma (Chardonnay, Pinot noir – sparkling), Lake (Cabernet Sauvignon, Zinfandel) and Santa Barbara (Pinot noir – red and sparkling). Discussions are underway for Napa (Merlot, a second site) and Santa Barbara (Chardonnay).
/wp-content/uploads/2017/09/AFV-Header-Logo.png 0 0 AVF /wp-content/uploads/2017/09/AFV-Header-Logo.png AVF1991-11-17 08:02:392017-11-17 08:03:18Evaluation of Winegrape Clones