The nutritional content of duckweed ( Lemna paucicostata hegelm.) in the Kainji Lake area, Nigeria

Abstract

Nutrient analyses were carried out on the duckweed Lemna paucicostata from three different locations. Crude protein level ranged from 26.3 to 45.5% of plant dry mass. The amino acid content of the plant compared favourably with that of blood, soybean and cottonseed meals and considerably exceeded that of groundnut meal. The levels of the essential amino acids surpassed the FAO reference pattern, except for methionine which met 61.4% of the recommended value. The levels of minerals were high but should not pose any toxicity problems if incorporated into animal feeds. The levels of nitrogen in the plant are comparable to those in commercial fertilizers. The plant could be a good dietary supplement and nutrient source for humans, livestock and fish and also could act as a good fertilizer supplement. With an average standing crop of 309 kg dry mass (DM) ha −1 and doubling time of 1.2 days, 129 kg DM ha −1 of dry duckweed are obtainable daily in the Kainji Lake area, which could ensure a daily supply of 59 kg of high-quality protein for poultry and fish feed formulation. Manual harvesting and sun-drying are economically feasible in the dry season, especially during harmattan (December and January). In the rainy season, a cheap solar drier can be conveniently used for drying.