Submitted to: Walnut Research Conference
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2005
Publication Date: 1/1/2005
Citation: Browne, G.T., Hackett, W., Krueger, W., Connell, J., Olsen, B., Lampinen, B., Mclaughlin, S., Lee, R., Potter, D., Grant, J., Mcgranahan, G., Leslie, C., Bujazha, D. 2005. Determining phytophthora resistance in elite paradox clones and specific etiology of a paradox crowne and root rot. Walnut Research Conference.
Technical Abstract: There has been continued interest in comprehensive evaluation of Paradox hybrids for resistance to Phytophthora spp. and other desirable traits. Paradox has proven more resistant than Northern California black or English seedling rootstocks to most Phythophthora spp. Although Chinese wingnut is the only walnut family relative known to tolerate P. cinnamomi, it is not graft compatible with all English walnut cultivars and has other potential limitations (i.e., suckering, unknown yield efficiency). Paradox hybrids available from commercial nurseries are diverse, involving crosses between J. regia and one or more species of black walnut and the results of greenhouse experiments suggested that the diversity among Paradox hybrids may include important variation in resistance to P. citricola.