Table 1 Effects of low temperature treatments on chlorophyll fluorescence parameters of C. bifida and C. panzhihuaensis

Fv/Fm

C. bifida

0.826 ± 0.006a

0.782 ± 0.015b

0.717 ± 0.046c

0.001 ± 0.002d

C. panzhihuaensis

0.857 ± 0.010a*

0.824 ± 0.004b*

0.819 ± 0.007b*

0.823 ± 0.009b*

Y(II)

C. bifida

0.462 ± 0.068a

0.325 ± 0.052b

0.152 ± 0.040c

0 ± 0d

C. panzhihuaensis

0.465 ± 0.050a

0.421 ± 0.044ab*

0.427 ± 0.018ab*

0.383 ± 0.026b*

Y(NPQ)

C. bifida

0.315 ± 0.084a

0.321 ± 0.045a

0.076 ± 0.057b

0.052 ± 0.005b

C. panzhihuaensis

0.260 ± 0.046b

0.288 ± 0.034ab

0.226 ± 0.030b*

0.313 ± 0.034a*

Y(NO)

C. bifida

0.224 ± 0.016d

0.354 ± 0.014c

0.776 ± 0.104b

0.948 ± 0.005a

C. panzhihuaensis

0.275 ± 0.016b*

0.291 ± 0.039b*

0.348 ± 0.023a*

0.304 ± 0.013b*

qp

C. bifida

0.744 ± 0.044a

0.533 ± 0.061ab

0.241 ± 0.054b

0.8 ± 0.0447a

C. panzhihuaensis

0.635 ± 0.048a*

0.644 ± 0.070a*

0.634 ± 0.019a*

0.588 ± 0.028a*

qN

C. bifida

0.682 ± 0.106b

0.596 ± 0.043b

0.134 ± 0.100c

0.987 ± 0.029a

C. panzhihuaensis

0.561 ± 0.050a*

0.602 ± 0.054a

0.490 ± 0.051b*

0.612 ± 0.043a*

rETR

C. bifida

120.4 ± 17.501a

83.6 ± 13.390b

38 ± 9.925c

0 ± 0d

C. panzhihuaensis

117.4 ± 12.740a

108.6 ± 11.127a*

108.6 ± 4.393a*

94.8 ± 6.686b*