Spring Mountain District AVA to the other Bordelaise grape varieties of Cabernet Franc, Petit Verdot and Malbec, a few sites favor and support small plantings of Zinfandel, Syrah, Petite Sirah and on the coolest sites, even a little Pinot noir. Of the whites over half is Chardonnay. The other significant plantings of white grapes in the AVA are Sauvignon blanc and White Riesling. Early on, the name Spring Mountain was used in a regional context and did not refer to the name of a peak or prominent point, rather than a particularly verdant area with numerous springs, and drained by several small streams. The
Petite mutation Petite mutation petite (ρ–) is a mutant first discovered in the yeast "Saccharomyces cerevisiae". Due to the defect in the respiratory chain, 'petite' yeast are unable to grow on media containing only non-fermentable carbon sources (such as glycerol or ethanol) and form small colonies when grown in the presence of fermentable carbon sources (such as glucose). The petite phenotype can be caused by the absence of, or mutations in, mitochondrial DNA (termed "cytoplasmic Petites"), or by mutations in nuclear-encoded genes involved in oxidative phosphorylation. A neutral petite produces all wild type progeny when crossed with wild type. petite mutations can