Durif The vine is a popular planting in Lake, Mendocino, Sonoma, Napa, Monterey and San Joaquin County. In addition to being produced as a varietal wine, the grape is sometimes blended with Zinfandel. In years when heavy rain or excess sun has weakened the quality or yield of Cabernet Sauvignon or Pinot noir plantings, Petite Sirah may also be used as a blending partner to strengthen the wine. The average age of Petite Sirah vines tends to be older than that of most Californian vines. As of December 2007, the TTB lists both Petite Sirah and Durif in 27 CFR §
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