Nutrient Uptake and Photosynthetic Pigment Contents of Tea (Camellia sinensis (L.) Kuntze) as Influenced by Light Intensities in Southwest Nigeria

Light influences many physiological processes in tea, as in all green plants. Tea production in the lowland area of Southern Nigeria is affected by Light Intensity (LI). Information on the response of tea to light intensity in the lowland is scanty. Therefore, the effect of LI on nutrient uptake and photosynthetic pigments contents of tea was investigated in Ibadan and Owena, southwest Nigeria. A field trial was conducted in the Research plots of Cocoa Research Institute of Nigeria Stations in Ibadan and Owena, Southwest Nigeria between 2016 and 2017 to evaluate the response of two tea cultivars, C143 and C318 to three LI which were achieved with sheds of different palm fronds layers (PFL): L1=[(2PFL-45% LI (4.57x104lux)]; L2=[(1PFL-65% LI (6.75x104lux)] and L3=100% LI (1.04x105lux) (control) under randomized complete block design with four replications. Data on Leaf nitrogen and magnesium uptake (mg/g) were obtained in the rainy season, and chlorophylls and carotenoids were obtained under rainy and dry seasons following standard procedures. Data were analysed with ANOVA and descriptive statistics at α0.05. L1 increased N and Mg by 149.78% and 155.10%, respectively, compared to L3 at Ibadan, and by 96.64% and 84.84%, respectively, at Owena. At Ibadan, 45% light increased chlorophyll by 69.62% and 147.78% compared to 65 and 100% lights, respectively in the dry season, and by 22.49% and 81.56%, respectively in the rainy season; whereas at Owena, L1 increased chlorophyll by 15.57% and 90.37% compared to L2 and L3, respectively in the dry season, and by 3.47% and 44.85%, respectively in the rainy season. At Ibadan, L1 enhanced the highest and lowest carotenoids in the rainy and dry seasons, respectively. The L2 caused the highest carotenoids, while L3 produced the least in the dry season at Owena. Therefore, for enhanced N, Mg, chlorophylls and carotenoids contents, reduced light intensities of 45 – 65% are recommended for growing tea in the dry and rainy seasons in Ibadan and Owena.