Seventy-five years of breeding dry bean of the western USA

A periodic comparision of cultivars is essential to assess selection gains, determine deficiencies, define objectives, and set breeding priorities. Our objective was to assess the progress, or lack thereof, achieved in improving yield, plant type, maturity, and reisitance to major bacterial, fungal, and viral diseases of dry bean of the western USA from 1918 to 1998. Twenty-five great northern, pink, pinto, and red cultivars were evaluated for the seed yield at 3 locations in Idaho and for anthracnose, Bean common mosiac necrosis virus, common and halo bacterial blights, Fusarium wilt, and white mold in Colorado, Idaho, Washington between 1999 and 2006. Yield ranged between 2904 kg ha(-1) for the pinto 'UI 111' to 3921 kg ha(-1) for 'Bill Z', which represents a 35% gain in 54 yr. Yield gain in great northern was 587 kg ha(-1) pink 136 kg ha(-1), and red 687 kg ha(-1). Stability indices ranged from 0.57 for 'Kodiak' to 1.86 for 'UI 3'. Maturity ranged from 90 d for 'UI 320' to 97 d for 'Frontier'. Seed weight ranged from 28 g for 'Viva' to 41 g for UI 320. An acceptable degree of resistance to Rhizoctonia root rot was achieved in most cultivars. All cultivars were sesceptible to anthracnose, common bacterial blight, and white mold, and all except 'Chase' to halo blight. Only 'Matterhorn', 'Weihing', and Kodiak combined an upright Type II growth habit with resistance to BCMV and rust. An integrated breeding strategy should be explored for the simultaneous improvement of multiple traits in future cultivars.