An article by Jen Pinkowski in Mental Floss discusses the lack of genetic diversity in the most commonly cultivated V. vinifera grapes.
“The vast majority of wine produced across the world derives from a single grapevine species: Vitis vinifera. The domesticated grape has thousands of varieties, and quite a lot of genetic diversity among them, according to a 2010 paper in PNAS that analyzed genome-wide genetic variation of more than 1000 samples of V. vinifera subsp. vinifera and its wild relative, V. vinifera subsp. sylvestris. But that’s not true for all grapes: Nearly 75 percent of cultivars had a first-degree relationship to at least one other. They were either parents or children.”
An article by Kevin Begos in the Smithsonian Magazine features the VitisGen2 project.
“VitisGen is a project that aims to do for wine what the Human Genome Project did for humans. That is: use the vast power and rapidly declining cost of DNA research to pinpoint the precise chromosomal locations in American grapes that drive flavors, aromas, grape size and other important attributes.”
Grape breeding PhD student Laise Moreira collects flower tissue for analyzing sex trait in grapevine as part of the VitisGen2 project at the University of Minnesota Horticultural Research Center in Excelsior, MN. (Matthew Clark / VitisGen)
A new publication out of UC Davis, co-authored by VitisGen2 genetics team member, Dario Cantu, investigated molecular changes in vines infected by Pierce’s disease. The bacterial disease is of major concern because it is vectored by a ubiquitous insect, the glassy winged sharpshooter, and it kills vines within 3-5 years by attacking the xylem. The study outlined a list of molecular markers for further investigation and possible use in breeding programs.
Symptoms of Pierce’s disease on a grapevine leaf. (Jack Kelly Clark / UC ANR)
April 19th 2018, 2pm EST – Automated Evaluation of Grape Breeding Progeny to Reduce the Phenotyping Bottleneck – watch recording
While genetic information is becoming inexpensive, measuring attributes of interest such as disease resistance or cluster architecture has been a laborious, manual process. VitisGen2 researchers are developing methods of more rapidly and objectively screening ‘mapping populations’. Their goal: to streamline the process of associating plant traits with genetic markers.
Panelists from the VitisGen2 Breeding and Local Phenotyping Team (left to right):
Lance Cadle-Davidson, VitisGen2 Project Co-Leader and USDA Research Plant Pathologist
Rachel Naegele, USDA Research Horticulturist
Anna Underhill, MSc student at University of Minnesota
Wines & Vines, March 2018 issue
By Tim Martinson
“For grape breeders and geneticists, the previous trickle of scarce genetic knowledge has turned into a flood of DNA sequence information. For the first time, there is enough sequence information to allow geneticists to make a detailed map of the 19 pairs of chromosomes and 500 million base pairs in the grape genome. This map enables them to locate genetic markers (short DNA sequences) associated with single gene loci, or what they call Quantitative Trait Loci (QTLs).” Read full article here
A vine susceptible to powdery mildew (left) and a resistant vine (right)