Phosphorus and potassium fertilization and mineral nutrition of soybean

Authors
Citation
E. Casanova, Phosphorus and potassium fertilization and mineral nutrition of soybean, INTERCIENCI, 25(2), 2000, pp. 92-95
Citations number
12
Categorie Soggetti
Multidisciplinary
Journal title
INTERCIENCIA
ISSN journal
03781844 → ACNP
Volume
25
Issue
2
Year of publication
2000
Pages
92 - 95
Database
ISI
SICI code
0378-1844(200003/04)25:2<92:PAPFAM>2.0.ZU;2-P
Abstract
An experiment was conducted for two years at Pale Seco (Guarico Slate, Vene zuela) on loamy and acid (pH 4.5) soils,vith high potential for soybean pro duction and low to medium levels of available P, K and Ca. The main objecti ve was to obtain maximum soybean (FP-3 variety) yields by using increasing rates of P (0-70 kg/ha) and K (0-135 kg/ha) fertilizers, and to study the e ffect of these nutrients on the mineral nutrition of the plant. The experim ental design used randomized blocks and the final plant density was equival ent to 400,000 plants/ha, with 3 replications. Seeds were inoculated with B radyrhizobium japonicum, and N (30 kg/ha), Ca (300 kg/ha) and Mg (40 kg/ha) were applied. A combined year yield analysis showed a linear response to P and K fertilizers and therefore maximum yields were not obtained. However, higher yields were produced in the first year, with better rainfall distri bution, and lower yields, due to excess moisture, occurred in the second ye ar. The combination of 70 kg P/ha and 108 kg K/ha produced the highest soyb ean grain yields at 12% moisture, of 2938 kg/ha for the first year and 2713 kg/ha for the second year. In 1997, where P was not applied the leaf P con centration was at the deficiency level, and the highest P concentration,vas reached with the rate of 60 kgP/ha. The 18 kgK/ha treatment produced K lea f concentration within the sufficiency range.