Breeding Rootstocks Resistant to Aggressive Root-Knot Nematodes
The USDA Agricultural Research Service (USDA-ARS) grape rootstock improvement program in Geneva, NY, has undergone significant changes in the past several years as a result of the resignation of Peter Cousins from his ARS rootstock breeder position and the abolishment of the vacated rootstock breeder position by ARS due to the federal budget cuts. However, a continued effort has been made to ensure that promising rootstock selections from previous years of breeding effort are maintained and carried through the evaluation process. To meet this challenge, a multi-discipline and –institution cooperative research team has been formed under encouragement and endorsement of the California grape industry. Matthew Fidelibus of University of California-Kearney Agricultural Research and Extension Center (UC-KARE) now leads the effort for evaluation of horticultural characteristics and graft performance of the rootstock selections generated from the Geneva rootstock breeding program. Gan-Yuan Zhong of the USDA-ARS Grape Genetics Research Unit (GGRU) in Geneva, NY, on the other hand, leads the effort for maintaining rootstock breeding populations and evaluating these populations and selections for root-knot nematode (RKN) resistance and propagation ability. The new team has been in operation since 2013 and demonstrated its success in evaluating more than 600 rootstock selections and identifying 5 leading rootstock selections for further grafting evaluation. During 2016-2017, the Geneva Team received $15,000 grant support for this project, which was only about 20%of what was requested. The team maintained about 150 rootstock mothervines in Geneva, evaluated 22 for RKN resistance and propagation ability, and transferred 27 to Matthew Fidelibus to grow at the UC KARE in Parlier, CA.