Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12870-020-02434-z/MediaObjects/12870_2020_2434_Fig2_HTML.png)
a Response of net photosynthetic rate (Anet) to photosynthetic photon flux density (PPFD) in Panax notoginseng grown under low nitrogen (LN), moderate nitrogen (MN), high nitrogen (HN). b The change of net photosynthetic assimilation (Anet) with intercellular CO2 concentration (Ci) in Panax notoginseng grown under different nitrogen levels. Values for each point were means ± SD (n = 7). Significant differences are indicated by asterisks (ANOVA; P values ≤0.05)