Testing Zinfandel Selections for Fanleaf Virus

A previous clonal evaluation trial was terminated with the conclusion that the certified clones of Zinfandel showed few differences in yield components, such as berries/cluster and berry size. The former is desired for contributing to lower rot potential and the latter for better color development. Over the past few years, efforts were made to identify new Zinfandel clonal selections from old, healthy-appearing vineyards with reputations for wine quality. Selections were made on the basis of observed fruit characteristics such as cluster shape and compactness as well as berry size. While vines were visually selected for freedom from disease, it was important to test for grapevine fanleaf virus (GFLV) to prevent the spread of that disease into the test site. Other costs for plot establishment were and will be borne by other sources of funding. The trial was established at the OakviUe Experimental Vineyard. St. George rootings were planted in spring of 1995 and 52 selections were chip-budded in September with an additional 11 selections scheduled to be spring-budded in 1996.