Figure 5.

Changes of CsGS1.1 expression levels and GS activities in hydroponic tea plants cultured with different levels of N and Mg. A)CsGS1.1 relative expression levels and B) GS enzyme activities in the leaf and root of tea plant treated with different levels of N and Mg. Error bars show the mean values ± SD (n = 3). Statistical analysis was carried out with Duncan's multiple range test. Different letters indicate significant differences (P < 0.05). GS, glutamine synthetase; ns, not significant. Tea seedlings were treated with 2 levels of Mg [1 quarter (Mg^L = 0.1 mmol/L) and 2 times (Mg^H = 0.8 mmol/L) concentration in the full-strength nutrient solution] and 2 levels of N [1 quarter (N^L) and 2 times (N^H) concentration in the full-strength nutrient solution].The four treatment groups were as follows: low N and low Mg (N^L + Mg^L), low N and high Mg (N^L + Mg^H), high N and high Mg (N^H + Mg^H), and high N and low Mg (N^H + Mg^L).