Potassium promotes yield, quality and economic returns of two sweet potato varieties in acidic loamy sand soil
Year: 2025
Type: article
Abstract: Potassium (K) deficiency can limit growth and yield of sweet potato, particularly in sandy soils with a low pH. Most previous studies that focused on investigating rate of K applied for sweet potato did not use strongly acidic sandy soil. Therefore, the objective of this study was to investigate the effects of K on growth parameters, storage root yield, quality, and economic return over fertilizer cost of two sweet potato varieties grown in a strongly acidic loamy sand soil in Kalasin province, Northeast Thailand. An experiment with a 2 × 4 split plot design and four replications was established. The factors consisted of two sweet potato varieties (Beni Haruka and Okinawa-Kugani-Imo) and four K rates, 0 (control), 30, 60 and 90 kg K ha-1. At the rate of 90 kg K ha-1, storage root yield, total soluble solids, and economic return of Okinawa-Kugani-Imo variety were better than those of Beni Haruka. Storage root yield and economic return of Okinawa-Kugani-Imo were significantly increased with increasing K application rate up to 90 kg K ha-1, while Beni Haruka had the same trend up to 60 kg K ha-1, but had no significant differences when increasing the rate to 90 kg K ha-1. Therefore, recommended K application rates for sweet potato variety Okinawa-Kugani-Imo and Beni Haruka, grown in the dry season after paddy rice harvest in the acidic loamy sand soil, were 90 and 60 kg K ha-1, respectively.
Language: English
Subfield: Soil Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W4410219659