Syrah vine health
Syrah vine health symposium brings researchers to the foothills.
Researchers from the University of California, USDA, South Africa and France shared information on the current state of knowledge about the unique growth problems of Syrah during a three day tour of California Syrah vineyards that culminated in the Syrah Vine Health Symposium meeting held November 6 at UC Davis. I had the pleasure to host Mark Battany (UCCE Viticulture Farm Advisor in San Luis Obispo and Santa Barbara Counties) , Jerry Uyemoto (USDA virologist), Dariusz Goszczynski, (Plant Protection Research Institute virologist, South Africa), and Anne-Sophie Renault-Spilmont (ENTAV-ITV virologist, France) for a foothill Syrah vineyard tour and learned a lot about diagnosing “red leaf” and decline in sick Syrah vines.
Syrah Decline is the name given to the disorder of Syrah grapes characterized by deep grooving and pitting just above the graft union and sometimes up into the cordons, resulting in poor nutrient translocation, early red leaves beginning in late summer, stunted cane growth and, in some cases, death of the vine. The cause of Syrah Decline is not yet known, but this symposium brought an opportunity to hear opinions from experts around the globe. Some researchers believe Syrah Decline is caused by a yet unknown virus, others think it may be an abiotic disorder caused by herbicide injury to especially sensitive clones.
Look for a complete article about Syrah decline and “red leaf” in my December '07 newsletter. Symposium articles are available at this link UC Integrated Viticulture Online website: Syrah Decline & Disorder.