Effect of Irrigation during Early Developmental Stages on Yield and Shape in Sweet Potato Cultivar “Beniazuma”

Abstract

In Chiba prefecture, short storage root (length/width<2.5) occurred frequently in sweet potato (Ipomoea batatas (L.) Lam.) cultivar “Beniazuma”. As this was considered to be an effect of dryness in the early developmental stage, which determines the length of the storage root, we clarified the effects of watering in the early developmental stage on the growth, yield and occurrence of the short storage root. In this study, experimental plots were set up without irrigation, immediately after planting, 10 days after planting, and 10 days plus 30 days after planting. As a result, in the two plots that were irrigated 10 days after planting, compared to the non-irrigated plot, occurrence of the short storage root decreased due to the lengthening of thestorage root. This indicated that the dryness in the early developmental stage may cause short storage root and thatirrigation10 days after planting was effective for reducing occurrence ofshort storage root.