FIGURE 4.
Effect of exogenous brassinosteroid on theanine concentration in tea leaves under normal and SHT conditions. CK, Control; BR, 24-epibrassinolide; SHT, sub high temperature. Foliar portion of 2 years-old tea [C. sinensis (L.) O. Kuntze cv. Longjing 43] seedlings were pretreated with 0.2 ppm BR until surface run-off. Twelve hours later, seedlings were exposed to SHT (35°C) for 5 days in temperature-controlled chambers. BR was reapplied 12 h prior to sample harvesting. Control plants were sprayed with ddH2O and kept under normal temperature (25°C). Data are presented as the mean of six replicates (±SD). Different letters indicate significant differences (P < 0.05) according to the Tukey’s test.