Chemical analysis informs potential hybridization efforts
FRISCO — As the widespread and disastrous consequences of heavy pesticide use become ever-more apparent, wine-makers and grape growers are trying to figure out ways to make their grapes more resistant to bugs and fungi without using toxic chemicals.
The answer may lie in crossing the domestic grape species used in most wine production — Vitis vinifera — with native wild American grapes, like Vitis californica, which make terrible wine but are pest-resistant.
A new study, published in the American Chemical Society’s Journal of Agricultural and Food Chemistry, describes a comparison of the two species, to see which traits winemakers should borrow from each to make the best wine grape. Fulvio Mattivi and colleagues wanted to fill that gap.
The researchers found that, compared to the high concentrations in the vinifera varieties in the study, the American grapes had low levels of metabolites such as procyanidins that are considered crucial to the body and healthfulness of fine wine. They were also missing several compounds common in vinifera grapes that lead to appealing aromatic notes. But the American species were high in polyphenolic compounds called stillbenoids that are anti-fungal.
The particular hybrids analyzed in the study, however, contained low amounts of procyanidins and other desirable compounds. The researchers concluded that this kind of chemical profiling will help inform future breeding studies to design a better grape.