Among seasonal practices that affect grape quality, selective leaf removal at the cluster zone is accepted as a powerful technique to manipulate flavonoid content of grapes and wines. However, most of research on fruit-zone defoliation has been conducted under temperate climate and it remains uncertain if cluster exposure would be a recommendable practice in semiarid viticultural areas. In this...

Many robot arms can accomplish one task using many different joint configurations. Often only one of these configurations is used as a goal by the path planner. Ideally the robot’s path planner would be able to use the extra configurations to find higher quality paths. In this paper we use the extra goal configurations to find significantly shorter paths that are faster to execute compared to a...

A 3-yr field study was conducted at commercial juice grape (Vitis labrusca L.) vineyards to develop an economic injury level (EIL) for grape berry moth, Paralobesia viteana (Clemens) (Lepidoptera: Tortricidae) and to determine patterns of cluster injury. Infestation of grape clusters by P. viteana was measured biweekly from bloom until harvest, and fruit was sampled immediately before harvest t...

Although domestication of the grapevine (Vitis vinifera L.) has been extensively documented, the history of genotype selection and evolution of vineyard management remain relatively neglected fields of study. The find of 454 waterlogged grapevine pips from a well-dated Etrusco-Roman site in the Chianti district (Tuscany, Central Italy) is an extraordinary chance to gain insights into the progre...

A site was prepared with 2 distinctly different soil depths and a vineyard of 'Concord' grapes (Vitis labrusca L.) was established with in-row spacings of 1.52, 1.83, 2.13, 2.44, and 3.05 m. Wider in-row vine spacings resulted in increased vine yields on deeper soils to the point that yields per meter of cordon and per hectare were not reduced; but yield per meter of cordon and per hectare was ...

Yield, growth, and vigor of individual grape vines were correlated with nematode population densities in a series of California vineyards. In a Hanford sandy loam soil, Xiphinema americanum densities showed negative correlations with yield, growth, and vigor of vines. When vines were categorized according to vigor, X. americanurn densities had little relationship to yield of high-vigor vines, b...

This article considers application of a clusters approach to the California wine industry. After examining the idea of clusters in the context of industrial-complex economics, agglomeration economics and social network economics, we assess the usefulness of a cluster to consider the competitiveness of the California wine industry for national and global sales, export development and vineyard pr...