Agri Kultuur March/ Maart 2016 - Page 25

Malaga Chillies been grown in aquaponic systems. However, the goal is to select a vegetable for culture that will generate the highest level of income per unit area per unit time. Using this criterion, culinary herbs are the best choice. They grow very rapidly and command high market prices. The income from herbs such as basil, cilantro, chives, parsley, portulaca, and mint are many times higher than that from fruiting crops such as tomatoes, cucumbers, aubergine, and okra. Fruiting crops also require longer culture periods (90 days or more) and are subject to more pest Live Lettuce Vision Sweetcorn problems and diseases. Lettuce is another good crop for aquaponic systems because it can be produced in a short period (3 to 4 weeks in the system), and, as a consequence, pest risk is relatively low. Unlike fruiting crops, a high proportion of the harvested biomass is edible. Other suitable crops include Swiss chard, pak choi, Chinese cabbage, collard and watercress. Good results have been obtained with marigold and zinnia (flowers) in UVI’s aquaponics system. Traditional medicinal plants and plants used for the extraction of modern pharmaceuticals have not been cultivated in aquaponic systems, but there may be potential in growing some of these plants. Many new modern hybrid vegetables are also available from seed suppliers. Nutrient Balance: As an innovative sustainable food production system, the challenge in aquaponics is to use the nutrient input efficiently, minimizing its discard and tending to a zerodischarge recirculating system. Fish feed, the main nutrient input, can be divided into assimilated feed, uneaten feed, and soluble and solid Live Letuce in Supermarket Shelf