Decline in tuber number and weight of potato (<i>Solanum tuberosum</i> L) associated with drought in 2020 and 2021 in a humid region of eastern Hokkaido

The objectives of this study were to verify changes in potato tuber number and weight under climatic variations a cool region Japan. We investigated growth over 3-year period from 2019, establishing plots with different planting times maturity types. In 2020, early encountered dryness during the formation after sprouting, which significantly reduced numbers. Temperature was identified as main factor contributing annual variation yield, largely due unusually high temperatures period. 2021, hot dry conditions summer (mid late July) corresponded bulking yield owing light regardless time variety. present provided insights into variability components by focusing on drought effects, weather, cultivation factors, vary substantially.