Response of carrot (Daucus carota L.) yield and quality to organic fertiliser

Abstract

A field study was conducted at Umsunduze Training Centre, KwaZulu-Natal, for two seasons (2005 and 2006) to determine the response of carrot (Daucus carota cv. Kuroda) to organic fertiliser. Three different organic fertilisers were applied at four rates (chicken manure: 0, 6.25, 12.5 and 25 kg 10 m−2; kraal manure: 0, 12.5, 25 and 50 kg 10 m−2; and compost: 0, 25, 50 and 100 kg 10 m−2). The experiment was laid out as a complete randomised block design with four replications. Leaf number and length, root fresh and dry mass, root length, shoulder diameter, root total soluble solids (TSS) and grade were recorded. Chicken manure-treated plants produced more leaves than compost (2005) and longer leaves than kraal manure (2006) treated plants. The TSS of roots treated with chicken manure or compost was lower than that of roots not receiving fertiliser (2005). Poorer quality roots were harvested from compost than chicken or kraal manure-treated plants. As organic fertiliser rate increased, leaf number, length, root fresh mass and shoulder diameter increased. Root TSS and dry mass decreased as organic fertiliser rate increased and roots were of a lower grade. Organic fertiliser can be beneficial to carrot yield and quality within specific application levels.