Duckweed is a small flowering plant that grows on still water.
Duckweed is the world's smallest flowering plant. Roughly 40 species of duckweed exist and grow worldwide; these very small aquatic plants grow so rapidly that a single floating colony can double in size in less than 48 hours. Duckweed grows best in temperate and tropical climates, and prefers areas with little wave or wake, where it is sheltered from the wind; though it has also been found in areas with extreme temperatures and growing conditions. Duckweed plants remove a very high percentage of nutrients from the water during their growth cycle, and so are potentially valuable both as a food source and as a water purification system.
Water
Fresh duckweed is between 90 and 95 percent water; this is not surprising since it is an aquatic mass with a low enough density to float. To measure its other nutritional values, scientists look at its dry mass.
Protein
Duckweed has gained the attention of agricultural specialists interested in its potential as a feed supplement for livestock because of its high protein value. Duckweed grown in cultivated conditions can contain up to 45 percent crude protein in its dry mass. The chemical makeup of these proteins, rich in the essential amino acids lysine and methionine, make it compositionally more like an animal protein than a vegetable protein.
Fiber
The plant as it naturally occurs typically has a fiber content of between 15 and 30 percent. In ideal water conditions however, duckweed can be cultivated with as little as 5 percent fiber in its nutritional composition. As growth conditions improve and the fiber mass is minimized, the total amount of protein in the plant is maximized.
Other Nutritional Elements
The dry mass of duckweed, when tested, contained between 1.8 and 9.2 percent lipid tissue, and between 14.1 and 43.6 percent carbohydrates. Cultured duckweed, specifically, has demonstrated larger concentrations of certain trace minerals and pigments, like beta carotene and xanthophyll, nitrogen and phosphorus.
Growth
Because of its rapid growth and its nutritional composition, duckweed is being studied as a potential food source for poultry, hog, cattle, and human consumption. The fiber content of popular feed grains like soy and milo can be as high as 50 percent, which is not readably digestible. Duckweed, as a feed source, could be broken down and more completely consumed by the animal, increasing feed conversion rates. Also, the whole duckweed plant can be used as feed, saving the processing expenses and plant waste associated with feeding grain. In terms of dry mass grown per acre, duckweed could be grown on 10 percent of the space required to produce a similar amount of soybeans, and would only require 20 percent of the space required to grow the equivalent amount of corn.
Tags: between percent, areas with, fiber content, flowering plant, food source, nutritional composition
