The Impact of Shading on Growth and Yield of Cabbage (Brassica oleracea L.) in the Low Country Dry Zone, Ampara, Sri Lanka

Shade level is a predominant factor which greatly influences the high growth, quality and yield of an exotic vegetables which are mainly grow in low and mid country dry zone areas. Accordingly, a field trial was conducted to investigate the impact of shading on growth and yield of cabbage var. “Green Coronet” in Ampara district of Sri Lanka during the period of July to November 2020. The experiment was laid out in Completely Randomized Design (CRD) with four replicates. Level of shades were defined as treatments namely: T1: Open field condition (40%) and T2: 70% shade levels. Growth Measurements such as plant height, number of leaves and diameter of rosette were taken at six and eight weeks after transplanting and Analysis of Variance was performed to determine the significant difference among treatments (p< 0.05). Further, the head weight and yield was recorded at the harvesting stage and the results revealed that the cabbage plants grown at 70% shade level showed significantly (p<0.05) better performance in measured growth parameters viz. plant height, diameter of rosette, number of leaves especially after 50 days of transplanting (8WAP) and yield parameter of average head weight and yield. Whilst the lowest performance was observed in plants grown at open field conditions with 40% (T1) shade level. The study could be concluded that the plants grown at 70% shade level would have obtained high growth and yield with the provided temperature, relative humidity level and optimum light intensity in the protected environment. These findings will be benefited for the farmers who want to grow cabbage in a low country dry zone at a commercial scale and which will bring them higher yield rather than cultivates same in an open field conditions.