Effect of Rotation on Crop Yield and Quality in an Irrigated Potato System

The productivity of potato (Solanum tuberosum L.) systems may be strongly influenced by rotation. A field study consisting of six rotations (potato with canola (PC), wheat (PW), canola-wheat (PCW), oat-wheat (POW), wheat-canola-wheat (PWCW), and canola underseeded to alfalfa-alfalfa-alfalfa (PCAA)) arranged as an RCBD was established on a clay loam in Manitoba, Canada in 1998 and monitored for twelve years to determine effects on potato yield and quality. Higher yields for canola-containing rotations were evident in three years (P < 0.10), but not beyond 2005. From 2007 onward, 2-year rotations produced a markedly lower yield than other rotations. Yields of 3- and 4-year rotations were similar, although PCW and PCAA were most frequently among the higher-yielding rotations. Overall, PC had a lower specific gravity than other rotations. Results suggest 3- and 4-year rotations, particularly PCW and PCAA, helped maintain productivity. Two-year rotations of PC and PW were not sustainable due to declining yields.