2005 Annual Report 4d.Progress report. This report serves to document joint research conducted under a trust agreement between ARS and the California Table Grape Commission for research on the development of new table grape cultivars, including types resistant to powdery mildew. Additional details of research can be found in the report for the parent project 5302-21220-004-00D Improvement of Prunus and Vitis Scion and Rootstocks for Fruit Quality and Pest Resistance. There is a need for a series of seedless table grape cultivars with red, white and black fruit that ripen from early to late in the season to provide fresh grapes to the consumer for as long a period as possible. A total of 2,049 table grape seedlings were developed by in-vitro culture from 77 seedless x seedless crosses and planted in the field this year. They were developed from 18,106 ovules that produced 3,922 (22%) embryos. Fourteen new seedless grape selections (4 red, 6 black and 4 white) were determined to be promising and propagated in our 25 vine advanced test plot. They were chosen from 310 table grape selections of which 72 were new in 2004. Over 758 samples for storage tests were evaluated. One late red, one late white and two early white seedless selections continue to show commercial promise. Patent applications were submitted for a mid-season red seedless grape and a late season white seedless grape. They are being released as Scarlet Royal and Autumn King, respectively. Powdery mildew resistant table grape cultivars are needed to reduce the need for chemical control. This spring, 206 and 101 seedlings from 19 seedless x seedless and 12 seeded x seedless crosses, respectively, resistant to powdery mildew in greenhouse tests were planted in the field. Sixty-one new table grape selections with powdery mildew resistance were kept. Fruit evaluation of 271 previously made selections continued and 180 propagated for a new advanced plot at Parlier, California. Dormant cuttings were taken of 149 table and raisin selections and tested for powdery mildew resistance in the greenhouse and 43 had an average leaf rating of less than 1.5. This material has potential to provide germplasm and cultivars to revolutionize the industry with powdery mildew resistant table grape cultivars.