Tempranillo blanco region came to an agreement that would allow the planting and use of Tempranillo blanco in white Rioja wines produced under the DOC labels. Tempranillo blanco was one of three native white varieties added to permitted list of Rioja grapes--Maturana Blanca and Turruntes being the others. Additionally, Maturana Tinta, Maturano, Monastel, Chardonnay, Sauvignon blanc and Verdejo were added with Tempranillo blanco in the first major change of the Rioja wine laws involving grape varieties since the wine region was officially established in 1925. Under the DOC rules, in order to have new plantings of Tempranillo blanco vineyards must pull up
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