Pierce's Disease
Research Updates

piercesdisease.cdfa.ca.gov

What is Pierce's Disease?

Pierce's Disease is a bacterial infection, which is spread by bugs that feed on grapevines, particularly the "glassy winged sharpshooter." Grapevines that become infected with PD can quickly become sick and die.

glassy-winged sharpshooter

Identity and parentage of Torrontes cultivars in Argentina


  • Author(s): Aguero, Cecilia; Dangl, Gerald; Martinez, Liliana; Meredith, C; Rodriguez, Jose;
  • Abstract: Torrontes riojano is an aromatic white grape variety cultivated in Argentina that produces a dry wine with distinct muscat flavor. Two other Torrontes types, Torrontes sanjuanino and Torrontes mendocino, are of lower enological quality. Origin of the Torrontes cultivars has been the subject of speculation because efforts to relate them to European varieties have been unsuccessful. Microsatellite DNA polymorphism analysis was used to characterize these three cultivars and to attempt to clarify their origin. Moscatel amarillo, an Argentine cultivar with a phenotype very similar to that of Torrontes riojano, was also included in the study. Twenty microsatellite loci were analyzed in several accessions of each of the four cultivars. All four cultivars were found to be distinct. The results indicated, with a high degree of probability, that Torrontes riojano, Torrontes sanjuanino, and Moscatel amarillo are each the progeny of a cross between Muscat of Alexandria and Criolla chica and that Torrontes mendocino is also likely the progeny of Muscat of Alexandria, although the other parent has not been identified. A close relationship between the Torrontes and Muscat of Alexandria has been suspected, but the genetic contribution of Criolla chica was unexpected.
  • Publication Date: Jan 2003
  • Journal: American Journal Of Enology And Viticulture