Sungcom Techawongstien

Light intensity affects capsaicinoid accumulation in hot pepper ( Capsicum chinense Jacq.) cultivars

Strong light intensity affects plant growth, fruit yield, and accumulation of capsaicinoids in hot peppers (Capsicum spp.) which are important food and medicinal products. Shading improves plant growth and fruit yield in bell pepper (Capsicum annuum), but research on the effect of shading on high pungency C. chinense cultivars is limited. This study investigated the responses of C. chinense cultivars to different light intensities to maximize capsaicinoid production. An experiment to test the effect of shading, i.e., no-shading (full light intensity as control), 50% shade and 70% shade of full light intensity, was conducted in a plastic-net house using four C. chinense cultivars with different pungency levels: Bhut Jolokia, Akanee Pirote, Orange Habanero, and BGH1719. The cultivars showed different capsaicinoid production levels depending on the shade level. The highest capsaicinoid yields were found in the F1 hybrid cultivar Akanee Pirote under 50% shading (4,820 mg/plant) and in the Bhut Jolokia cultivar under 70% shading (3,419 mg/plant). By contrast, the BGH1719 plants showed the lowest capsaicinoid production (291 mg/plant) when shade was applied. These results demonstrate that capsaicinoid production in the studied cultivars is affected by light intensity. It is recommended that growers of high pungency cultivars use the appropriate level of shading for the particular cultivar to increase capsaicinoid yield.