Effect of Mulch and Irrigation on Growth, Yield and Quality of Radish (Raphanus sativus L.) in a Semi-Arid Sub-Tropical Environment

Radish is grown as an irrigated crop which can not tolerate water shortage. However, it has received relatively little research pertaining to its mulching and water requirements. The objective of this experiment was to investigate optimum water requirements of radish when using different mulching materials. The experimental design was a randomized complete block design with 12 treatments, replicated three times. The treatments were (three mulching matarials) grass mulch, black polyethylene cover, clear plastic cover and no cover (control), with each subjected to three irrigation regimes (100, 70 and 50% MC). The data collected on plant parameters included plant height, number of leaves, leaf length, leaf width, root diameter, % Total Soluble Solids (% TSS) of extracted juice, fresh mass of leaves and roots. Significant (p<0.05) plant growth increases were observed from treatment of grass mulch at 100% MC on plant height, root diameter, TSS (%) and fresh mass when compared to the other treatments. This was followed by clear plastic at 100% MC, black plastic at 100% MC and lastly the treatment of no cover at 100% MC. Similar results were obtained at 70 and 50% MC. There were no significant interaction between treatments (M × MC) for growth and yield parameters measured. Only grass mulch at 100% MC produced significantly (p<0.05) higher number of leaves than all the other treatments which had similar number of leaves. Root diameter varied significantly (p<0.05) across all treatments. The widest root diameter was obtained from grass mulch at 100% MC followed in decreasing order by no mulch at 100% MC, grass mulch at 70% MC and lastly black polyethylene at 100% MC. .