. 2017 Aug 2;8:1328. doi: 10.3389/fpls.2017.01328

Table 2.

Recovery rate of the performance index (PIabs) of photosystem II, and non-cyclic and cyclic photophosphorylation activities (NCPSP and CPSP, respectively) in Pogonatum cirratum subsp. fuscatum and Hypnum plumaeforme exposed to the indicated amount of N addition, with or without low temperature stress after a 10-day-recovery period (+LTS and −LTS respectively).

N treatment (kg N hm⁻² year⁻¹)		Nitrate treatment			Ammonium treatment
		PIabs	NCPSP (μmol ATP mg⁻¹chl min⁻¹)	CPSP (μmol ATP mg⁻¹chl min⁻¹)	PIabs	NCPSP (μmol ATP mg⁻¹chl min⁻¹)	CPSP (μmol ATP mg⁻¹chl min⁻¹)
**Pogonatum cirratum subsp. fuscatum**
−LTS	0	0.021 ± 0.008a	−0.032 ± 0.030	0.008 ± 0.008	0.021 ± 0.008a	−0.032 ± 0.030	0.008 ± 0.008
	20	0.032 ± 0.005a	−0.042 ± 0.027	−0.001 ± 0.022	0.061 ± 0.034ab	−0.014 ± 0.021	−0.006 ± 0.015
	40	0.134 ± 0.004b	−0.022 ± 0.020	−0.005 ± 0.029	0.102 ± 0.031bc	−0.037 ± 0.020	−0.014 ± 0.022
	60	0.219 ± 0.030c	−0.027 ± 0.012	−0.007 ± 0.023	0.115 ± 0.016c	0.011 ± 0.004	−0.014 ± 0.012
+LTS	0	0.948 ± 0.024c	0.056 ± 0.002a	−0.024 ± 0.017	0.948 ± 0.027d	0.056 ± 0.002	−0.024 ± 0.017
	20	0.905 ± 0.013c	0.155 ± 0.021bc	0.001 ± 0.009	0.751 ± 0.028c	0.083 ± 0.031	−0.011 ± 0.029
	40	0.554 ± 0.046b	0.184 ± 0.011c	−0.023 ± 0.011	0.513 ± 0.019b	0.062 ± 0.013	0.005 ± 0.022
	60	0.423 ± 0.028a	0.121 ± 0.030b	−0.004 ± 0.006	0.437 ± 0.013a	0.082 ± 0.017	0.006 ± 0.002
Hypnum plumaeforme
−LTS	0	0.001 ± 0.023a	−0.005 ± 0.005bc	−0.005 ± 0.030	0.001 ± 0.023	−0.005 ± 0.005b	−0.005 ± 0.030
	20	−0.020 ± 0.007a	0.012 ± 0.023c	−0.021 ± 0.005	0.007 ± 0.013	−0.017 ± 0.022ab	0.007 ± 0.018
	40	0.024 ± 0.032a	−0.034 ± 0.021ab	0.023 ± 0.026	0.115 ± 0.026	0.009 ± 0.021b	−0.024 ± 0.004
	60	0.117 ± 0.030b	−0.057 ± 0.016a	−0.026 ± 0.010	0.262 ± 0.004	−0.038 ± 0.008a	−0.008 ± 0.026
+LTS	0	1.107 ± 0.010d	0.293 ± 0.012ab	−0.042 ± 0.011	1.107 ± 0.010	0.293 ± 0.012a	−0.042 ± 0.011a
	20	0.982 ± 0.033c	0.291 ± 0.031a	0.003 ± 0.028	1.005 ± 0.013	0.409 ± 0.034c	−0.029 ± 0.008ab
	40	0.829 ± 0.034b	0.328 ± 0.014b	−0.026 ± 0.004	0.789 ± 0.051	0.361 ± 0.013b	−0.009 ± 0.020b
	60	0.716 ± 0.008a	0.264 ± 0.014a	−0.022 ± 0.022	0.702 ± 0.020	0.305 ± 0.030a	0.049 ± 0.014c

Data are presented as means ± S.D. (n = 3). Different letters indicate significant differences between samples exposed to various levels of N addition under each temperature treatment (p < 0.05, one-way ANOVA, LSD test). Data in bold format represent significant differences with 0 (p < 0.05, t-test).