Influence of Effluents from Intensive Aquaculture and Sludge on Growth and Yield of Bell Peppers

Abstract

ABSTRACT A study was conducted to evaluate effluents from intensive tank culture of Florida red tilapia (Oreochromis urolepis hornorum O. mosambicus) for field production of bell peppers (Capsicum annuum L.). Water from fish rearing tanks with low (8 fish m□ 3) and high (16 fish m□ 3) stocking densities and two daily water exchange rates (0% and 5%) were applied to plots grown with bell peppers two to three times weekly. These treatments were compared with solids (sludge) removed from the fish rearing tanks, cow manure and commercial N fertilizers. In 1992, marketable pepper yield was highest (9.0t ha□ 1) in plots applied with liquid N fertilizer (fertigation), followed by plots fertilized with tank sludge (5.0t ha□ 1). The lowest pepper yield (1.9 t ha□ 1) was obtained from plots fertilized with low density tank water. Yield from fertigated plots was significantly higher (P < 0.05) than all other treatments. In 1993, differences in yields from plots fertilized with rearing tank water from two exchange rates and inorganic N fertilizer were not significant (P > 0.05). Marketable yield was highest (10.4 t ha□ 1) in plots treated with tank sludge. Leaf tissue concentrations of N, P and K were at sufficient levels and were not significantly (P > 0.05) influenced by either aquaculture effluents and inorganic fertilizer treatments. Soil nutrient levels after harvest of second year crop were similar in all treatments.