Submitted to: American Phytopathology Society
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2006
Publication Date: N/A
Technical Abstract: Recessive disease resistance genes such as barley mlo resistance to powdery mildew can provide a durable, inexpensive control tactic. Random mutagenesis provides one approach for identifying recessive alleles in a cultivable background, and mutant populations can be screened for phenotypes-of-interest (forward genetics) and for allelic mutations in sequences-of-interest (reverse genetics). A pipeline for creating and analyzing EMS-generated mutants in grapevine was designed and implemented in a Chardonnay background. Three thousand selfed, segregating (M2) mutant populations were generated and either screened for resistance to foliar fungal pathogens or deposited in a grapevine TILLING (Targeting Induced Local Lesions IN Genomes) genetic stock collection. Individual seedlings resistant to powdery mildew or downy mildew have been identified and resistance mechanisms characterized microscopically. A pilot TILLING project has been conducted to develop standard protocols for screening sequences in grapevine. The genetic stocks will be publicly available for TILLING at cost, and cuttings of interesting seedlings will be distributed by the Cadle-Davidson laboratory. This project will provide breeding germplasm with recessive disease resistance and a platform for functional genomics in grapevine.