Effects of High Glucosinolate Mustard on Red Potato Yield and Skin Quality

Abstract

Yield and disease resistance are important components influencing potato growers’ variety selection. Potato appearance, nutritional content, and specific culinary uses often affect consumer selection. A 3-year study was conducted to investigate how red potato (Solanum tuberosum L.) yield and skin quality were affected by variety and previous crop and specifically if red potato varieties would benefit from a plowed-down high-glucosinolate mustard (HGM; Brassica spp.) cover crop. The three previous crops were barley (Hordeum vulgare L.), canola (Brassica napus L.), and HGM. Each season six red varieties were planted, and yield and skin quality were evaluated. Two red varieties were planted consistently across three growing seasons, and three were similar across two growing seasons. Potatoes were harvested, washed, graded, weighed, and rated for skin surface quality. Potato yields were influenced by variety and year (due to variable environmental conditions), but the previous crop only influenced yield in the wettest year, when potato yield increased by 19%, probably from the N released from the HGM biomass. For varieties grown across similar environments, HGM cover crops resulted in a 52% lower incidence of black scurf. Thus, HGM green manures can be used to reduce soilborne pathogens.