Effect of Plant Growth Regulator on Growth, Yield and Catechin Content of Tea (Camellia sinensis (L.) O.Kuntze)

Catechins are one of the secondary metabolites contained in tea leaves. Cultivation practices such as pruning affect the shoot production and quality of tea yield. The use of plant growth regulators is a new breakthrough in tea plant engineering. This research aims to determine the interaction effect of type, height of pruning, and concentration of Benzil Amino Purine (BAP) and Gibberellin (GA) concentrations on tea plants' growth and catechin content after pruning. The experiment was conducted at Tea and Cinchona Research Centre Gambung in June 2018 until October 2018, with a split-plot design consisted of three factors as followed: main factor (a) type of pruning (clean and lung pruning); subfactor (b) pruning height (40 cm, 50 cm, and 60 cm); sub-sub factor (h) plant growth regulator (0 ppm, 60 ppm BAP, 50 ppm GA, 60 ppm BAP + 50 ppm GA). The result showed that 60 cm pruning and 60 ppm BAP in the third month after pruning significantly affected the chlorophyll content index (91,58I cci). There was an interaction between the pruning height of 60 cm and 50 ppm GA on fresh shoots weight per bush on the fourth plucking. Based on the response curve, at clean pruning, the optimum value at pruning height of 51.5 cm and 66,63 ppm BAP contributes to the catechin content of 1.88% while at lung pruning, the minimum value pruning height of 50.73 cm and 7.238 ppm with catechin content of 0.776%