Aw. Bekker et al., EFFECTS OF CORALLINE LIME ON NUTRIENT-UPTAKE AND YIELD OF FIELD-GROWNSWEET CORN AND PEANUTS IN OXIDIC SOILS OF WESTERN-SAMOA, Fertilizer research, 36(3), 1993, pp. 211-219
Effects of coralline lime on yield and nutrient uptake by sweet corn (
Zea mays saccharata Sturt.) and peanut (Arachis hypogea) were studied
at three locations in Western Samoa. Coarse (0-10 mm) coralline materi
al containing 31.1% Ca and 1.67% Mg was used as lime. There were two m
odes of application: band and broadcast, and three rates: 6, 12 and 18
ton ha-1. In the highest rainfall location, marketable yields were in
creased by 250% for peanut and 160% for sweet corn by liming at 6 ton
ha-1, relative to the unamended control. Peanut yield increases were a
ssociated with reduced Mn toxicity and/or with Ca and Mg deficiency. S
weet corn was less susceptible to Mn toxicity, but more responsive to
exchangeable Ca. The critical level of exchangeable Ca was found to be
about 2.0 cmol(+)kg Applying lime to a band of 0.25-m wide did not re
duce yield relative to broadcast. Soil cultivation caused the lime to
spread over a wider band, diluting the applied calcium with a larger s
oil volume, suggesting that less than 6 ton ha-1 broadcast coarse cora
lline lime could still be adequate for most Samoan soils.