E-mail this article to a friend | Printer friendly format | Submit A Comment

By For The Madera Tribune

A new hybrid grape vine developed to resist infection from Pierce's disease is expected to produce enough grapes this season to permit a small first harvest.

If the results are favorable, the resistant "vinifera crosses" may be certified for release in two or three years.

Andrew Walker, a University of California Davis geneticist, heads the project.

"We chose vinifera cultivars from a broad range of flavors, colors, tannin structure and production levels," he said, "so we could advance the resistant-winegrape breeding program on many fronts."

In addition to being certified, the vines will have to be bulked up and made available from nurseries, which accounts for the two to three years waiting time.

"There will be better material, with higher level of vinifera on the heels of the first releases at 87.5 percent," Walker said.

The bacterium that causes Pierce's disease is carried by the glassy-winged sharpshooter, which are considered a serious threat by grape growers.

Sharpshooters are found as close as Fresno County. Although a small number of sharpshooters were found in Madera in the past, the spread of the disease has been curtailed by the quick action of pest control inspectors and USDA.

Pierce's disease is a threat to agriculture because it kills grapevines. A parasitic wasp that helps combat the reproduction of sharpshooters has recently been released in Fresno.

Ramona Frances of The Madera Tribune contributed to this article