2011 Annual Report 1a.Objectives (from AD-416) The specific objectives of this project are to. 1)develop a rapid detection assay for Verticillium dahliae in spinach seed;. 2)determine where the fungus is located in spinach seed to develop effective seed treatments; and. 3)identify lettuce and spinach resistant to V. dahliae to limit spread via seed. 1b.Approach (from AD-416) Detection of the fungus in vegetable and spinach seeds will be carried out by PCR techniques; localization of the fungus in spinach seed will be determined by confocal microscopy; and spinach and lettuce will be screened for resistance to Verticillium wilt in greenhouses. Documents SCA with University of California Davis 3.Progress Report The localization of V. dahliae expressing green fluorescent protein in spinach plants and seeds was examined by confocal microscopy. V. dahliae was readily detectable in the xylem of spinach plants, in root cross sections, and in the fruit walls of spinach seed. The fungus was not detectable in the embryo and centralized seed tissues. However, the fungus thoroughly colonized the fruit wall. The work was exchanged with the ARS scientists through emails, scientific meetings, and personal conversations.