Effects of irrigation management on chipping potato (Solanum tuberosum L.) production in the Upper Midwest
Monday, July 26, 2021
3:00 PM - 3:15 PM
Irrigation is an essential input for profitable commercial potato production. A field study was conducted during the 2018 and 2019 field and storage seasons in the Central Sands region of Wisconsin, a region with high volume of potato production in the U.S., to evaluate the impacts of different irrigation regimes on three chipping potato varieties, Hodag, Lamoka, and Snowden. The treatments were implemented during the late-tuber bulking and tuber maturation growth stages and consisted of irrigation at 125%, 100%, 75%, and 50% of crop evapotranspiration (ET). Irrigation before the treatment period was at 100%ET for all plots, which is standard irrigation practice in commercial potato production. The effects of different watering regimes on tuber yield and quality were evaluated at harvest and during storage at 0, 4, and 8 months. It was found that compared to the standard practice, the over-irrigation treatment at 125%ET when tubers reached late bulking resulted in no significant increase in total yield, marketable yield, tuber quality at harvest and during storage, but it led to reduced irrigation efficiency (IE) and water-use efficiency (WUE) as well as increased nitrate leaching potential in both years. Contrastingly, deficit irrigation regimes at 75%ET or even 50%ET during the late season had no impact on tuber growth, could increase IE and WUE in one of the two years, and showed reduced drainage. In both years, irrigation rate had no significant effects on hollow heart incidence, tuber specific gravity at harvest, and fry quality during the 8-month storage. This study suggested that over-irrigation during late-bulking and tuber maturation stage was not beneficial for potato production in Central Wisconsin of the U.S., and deficit irrigation during these stages could potentially result in more sustainable water use without penalizing tuber yield, quality and storability of chipping potatoes.