Sweet potato (Ipomoea batatas (L.) Lam) response to fertility amendment in a shifting cultivation system of Nueva Viscaya [Philippines]

• Published in: Philippine Agriculturist Vol. 68
• Main Authors: Barker T.C, Sajise P.E
• Format: Journal Article
• Language: English
• Published: 1985
• Subjects: agricultural lime; application methods; augmentation de rendement; aumento del rendimiento; cal agricola; chaux agricole; clay soils; engrais npk; fertilizantes npk; filipinas; ipomoea batatas; methode d' application; metodos de aplicacion; npk fertilizers; philippines; rendement; rendimiento; sol argileux; suelo arcilloso; yield increase; yields
• ISSN: 0031-7454

Sweet potato [Ipomoea batatas (L.) Lam.] yield response to phosphorus, potassium, and lime treatments was assessed during two seasons at Imugan, Santa Fe, Nueva Viscaya, on Annam clay loam soil. Five treatments consisted of N-only (92 kg N/ha), N + P (50 kg P/ha), N + K (150 kg K/ha), N + lime (14.6 N + lime/ha), and N + P + K + lime at the above rates. During the first season, root and top yields from the complete treatment were significantly greater than those from the other treatments. Root yield response to N + P was significantly greater than N + lime, N + K and N only. Top yield response to N + P and N + lime was also significant. In the second season, no additional fertilizer was added in order to evaluate residual nutrient response. No significant differences among treatments were found for root yield or top yield during the second season. It was concluded that available phosphorus was yield-limiting at the study site. Liming to approximately pH 6.0 was beneficial, probably in terms of releasing some labile P and/or preventing added P from being fixed in an unavailable form.