. 2017 Sep 18;5:e3718. doi: 10.7717/peerj.3718

Table 1. Leaf microstructure characteristics and mean pigment concentrations in foliar tissues of Colobanthus quitensis from three origins along a sub-Antarctic—Antarctic latitudinal gradient.

Values are means ± 2 SE. Different lowercase letters indicate significant differences between populations (Tukey HSD tests, α = 0.05). Letters were ordered from higher to lower trait values (from a to c).

Trait	SouthAmerica	ShetlandIslands	AntarcticPeninsula
	(53.5°S)	(62.1°S)	(67.5°S)
*Microstructure*
Cuticule width (µm)	19.54 ± 2.48^a	16.16 ± 1.59^b	11.52 ± 1.68^c
Mesophyll width (µm)	358.28 ± 23.99^c	408.96 ± 7.62^b	454.01 ± 11.28^a
Palisade Parenchy ma width (µm)	91.72 ± 1.48^c	95.92 ± 1.52^b	107.56 ± 5.09^a
Spongy Mesophyll width (µm)	246.92 ± 24.68^c	296.88 ± 8.41^b	334.92 ± 12.52^a
Leaf transversal area (mm²)	0.43 ± 0.03^a	0.33 ± 0.02^b	0.25 ± 0.02^c
*Pigment contents*
Anteraxanthin (µg g⁻¹ DW)	73.73 ± 6.98^ab	77.06 ± 2.21^a	71.73 ± 3.03^b
Violaxanthin (µg g⁻¹ DW)	16.86 ± 2.64^b	18.13 ± 2.13^ba	19.46 ± 1.18^a
Zeaxanthin (µg g⁻¹ DW)	12.00 ± 3.29^c	24.46 ± 6.64^b	32.33 ± 5.89^a
DEPS	0.48 ± 0.02^c	0.52 ± 0.27^b	0.55 ± 0.02^a