Differences in the photosynthetic and physiological responses of Leymus chinensis to different levels of grazing intensity

Table 3 The chlorophyll fluorescence parameters of L. chinensis in the plots with different grazing intensities

	Control	LG	MG	HG
F_o	133.9 ± 6.53c	184.3 ± 5.58a	123.8 ± 6.70c	155.8 ± 2.51b
F_m	646.5 ± 13.0a	624.9 ± 46.1ab	502.2 ± 30.0c	599.3 ± 23.5b
F_v/F_m	0.79 ± 0.005a	0.76 ± 0.006a	0.78 ± 0.001a	0.77 ± 0.005a
F_v ‘/F_m’	0.501 ± 0.021a	0.424 ± 0.001b	0.377 ± 0.005c	0.446 ± 0.013b
q_P	0.509 ± 0.056a	0.583 ± 0.027a	0.503 ± 0.036a	0.595 ± 0.007a
NPQ	1.305 ± 0.230a	1.328 ± 0.557a	1.545 ± 0.444a	1.289 ± 0.252a
ETR	166.8 ± 16.8ab	130.0 ± 6.24b	150.0 ± 13.0ab	174.4 ± 6.77a
Φ_PSII	0.254 ± 0.025a	0.247 ± 0.012a	0.190 ± 0.016b	0.266 ± 0.010a

Values are means ± SE (n = 3). Values of a parameter labeled with different letters differ significantly between light intensities (ANOVA followed by LSD test, P < 0.05)
Control no grazing, LG light grazing, MG medium grazing, HG heavy grazing, F₀ minimum fluorescence, F_m maximum fluorescence, F_v/F_m the maximum quantum efficiency of PSII, F_v’/F_m′ energy harvesting efficiency of PSII, q_P photochemical quenching coefficient, NPQ non-photochemical quenching coefficient, ETR electron transport rate, Φ_PSII effective quantum yield of PSII

ISSN: 1471-2229