Fig. 3

Principle component analysis of the lipid profiles. PCA score plot (a) and PCA loading plot (b) using lipid profiles from mature leaves (ML) and new shoots (NS) of tea plant grown under three nitrogen levels at the rate of 0 (ML1/NS1), 285 (ML3/NS3), 474 (ML4/NS4) kg/ha, respectively. The red arrow (a) indicated that the effects of nitrogen application on ML and NS were contrary. Lipids in red color (b) were the most responsive compounds under different nitrogen levels according to the loading values of principle component 2