Abstract
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%.
