Mackinaw: A Round White Potato Variety with Excellent Long-Term Storage Chip-Processing Quality and Resistance To Late Blight, Potato Virus Y, Golden Cyst Nematode and Tolerance To Common Scab

Abstract Mackinaw is a disease resistant round white chip-processing potato with resistance to potato virus Y (PVY), late blight ( Phytophthora infestans ), and tolerance to common scab ( Streptomyces scabies ). Mackinaw also carries the TG689 marker for the H1 resistance gene to golden cyst nematode ( Globodera rostochiensis ) race Ro1. Designated as MSX540-4 during the trialling phase of its development, it was selected from a cross between the cultivars Saginaw Chipper and Lamoka. Field testing in Michigan show that this variety has average yield potential, similar to Snowden, with high specific gravity averaging 1.087. Mackinaw has a strong vine with a mid- to late-season maturity, producing a large percentage of A-sized tubers with a low incidence of internal defects and excellent long-term storage chip-processing quality. Mackinaw performed well in on-farm trials in Michigan and in multistate SNAC trials showing broad adaptation, especially in the northern tier states. Formally released in 2017, Mackinaw offers a unparalleled combination of disease resistance, long-term storage potential, and excellent chip-processing quality out of the field and out of long-term storage.