Tempranillo Navarra, and Penedès. During the 1990s, growers in Australia and South Africa started significant Tempranillo plantations. Tempranillo is a black grape with a thick skin. It grows best at relatively high altitudes, but it also can tolerate a much warmer climate. With regard to Tempranillo's production in various climates, wine expert Oz Clarke notes, In the Ribera del Duero the average July temperature is around 21.4° Celsius (70.5° Fahrenheit), though temperatures in the middle of the day in the lower valley can jump as high as 40 °C (104 °F). At night the region experiences a dramatic diurnal temperature variation,
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