Abstract
'Rainier Russet' was released in 2020 as a medium- to late-maturing selection with russeted tubers. Total yields are less, but similar to controls 'Ranger Russet' and 'Russet Burbank', and U.S. No. 1 yields are higher than Russet Burbank with increased tubers > 284 g. Compared to controls, it has high protein levels, high specific gravity, excellent fry color and flavor ratings, low acrylamide potential, good post-harvest merit scores for processing quality, and few internal and external tuber defects. Rainier Russet is susceptible to blight diseases, PVY, and Fusarium dry rot (F. solani var. sambucinum), but resistant to common scab (Streptomyces scabies) and Fusarium dry rot (F. solani var. coeruleum). Compared to Russet Burbank, tubers are less susceptible to hollow heart/brown center, secondary growth, growth cracks, and internal brown spot but higher tuber defects for net necrosis and shatter bruise with similar blackspot bruise potential. Rainier Russet is noted for its long tuber dormancy compared to Russet Burbank.