The dangerous Rebstock disease (PD for short) was first discovered in Southern California in 1880, when 20,000 hectares of vineyards were destroyed in five years. It is also known as California Vine Disease, Mysterious Disease or Anaham Disease (because it is common to Anaham in California). At this time the plant pathologist Newton B. Pierce (1856-1916) moved to California. Because of his services to her research, she was named after him. From 1933 to 1940 the most widespread was in California Central Valley, from where they spread across the south of the United States. Mexico and spread to Central America.
In the United States, the entire southern belt is from California in the west over Texas to Florida affected on the east coast. At the end of the 1990s, this disease increased again. US Vice President Al Gore approved emergency aid of $ 36 million in late 2000 and declared a (agricultural) state of emergency for California. In 2014, PD caused a loss of $ 104 million to the California wine industry. The disease does not yet occur in Europe. That probably prevents the cooler climate a spread to the north. If it is through the climate Change however, should it come this far (which is almost likely to be the case), it is predominantly Mediterranean areas that are threatened.
The disease is caused by the bacterium Xylella fastidiosa triggered, but this was only recognized in 1978 (previously one had virus supposed). The bacterium leaves the ability of the vines to transport their water completely wither in the period of one to three years and leads to complete drying up. Carriers are various to the family of cicadas counting grasshopper (leafhopper). The most dangerous species is Homalodisca vitripennis (formerly H. coagulata), known under the trivial name "Glassy-Winged Sharpshooter" (GWSS). This species can fly particularly far compared to its peers and thus infect many more plants. The first signs are usually a slight drying up and "burning" of leaf margins.
It arises necrotic Leaf margin with a chlorotic, yellowish band for white wine or a reddish one for red wine varieties. With the first symptoms, the fruits dry up too. The still small grape berries fall off, so that only the grape skeleton remains. Most infected vines die within a year, only a few sprout again the following year. Young plants are generally more susceptible. The effects are strongly dependent on the weather and the variety. The warmer the region, the more pronounced it is.
The species are particularly susceptible Vitis vinifera. Vitis labrusca and Vitis riparia, Of the European varieties are particularly at risk Barbera. Chardonnay and Pinot Noir, The University of California had already published a report warning of this in 1985, but Chardonnay continued to be enforced. Considered medium prone Cabernet Sauvignon. Gray Riesling. Merlot. Napa Gamay. Petite Sirah. Ruby Cabernet. Sauvignon Blanc and Thompson Seedless, Varieties of the species are considered resistant Vitis aestivalis. Vitis arizonica. Vitis berlandieri. Vitis candicans and Vitis rupestris, These are, among other things Ambulo Blanc. Blanc Du Bois. Caminante Blanc. Camminare Noir. Cham panel. Errante Noir. Favorite. Orlando Seedless. Paseante Noir and Roucaneuf,
Pierce Disease has a European relative, namely Flavescence doree, which is also transmitted by grasshoppers and causes comparable damage in southern France, Italy and Spain. So far, no effective remedy for both diseases has been found. However, researchers from the University of California managed to do so in 2002 with the help of a simple one virus to plant a silkworm gene in the genome of vines. This changed gene produces that protein "Cecropin", which kills the pathogen. At best, one wants to find a gene variant that produces the special protein in the vine, but not in the grapes. See also a list of all pests and diseases below Vine enemies,