ISSN: 0041-3216

ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 63 Number 2
Research Papers
Effects of fertilizers on yield and leaf nutrient concentrations in coconut
In experiments with coconut at three sites in Sri Lanka muriate of potash increased copra yield and leaf K and CI but decreased leaf Ca and Mg; saphos phosphate increased yield only at two sites but generally increased leaf P, Ca and Mg and decreased leaf K and CI; sulphate of ammonia had no effect on yield but generally increased leaf N and Ca and decreased leaf K and CI. The sufficiency ranges of nutrient concentrations (% in 14th leaf) estimated from the yield/leaf nutrient concentration relationships were: N. 1.9-2.1; P, 0.11-0.13; K, 1.2—1.5; Mg, 0.25—0.30; and CI, 0.30—0.40; that of Ca differed between the sites but was within 0.35-0.55%.
Keywords: Coconut; Yield; Fertilizers; Leaf nutrients