How do leaf anatomies and photosynthesis of three Rhododendron species relate to their natural environments?

Botanical Studies

Table 2 Leaf anatomical structure and stomatal characteristics of three Rhododendron species

Parameters	*R. yunnanense*	*R. irroratum*	*R. delavayi*
LT (μm)	262.42 ± 0.98a	247.47 ± 1.63b	243.98 ± 2.57b
CT (μm)	2.76 ± 0.12c	5.93 ± 0.11a	3.76 ± 0.10b
ET_ad (μm)	40.09 ± 0.46a	39.45 ± 0.32a	35.46 ± 0.46b
ET_ab (μm)	13.93 ± 0.33a	7.98 ± 0.11b	7.18 ± 0.14c
PT (μm)	91.53 ± 0.80a	84.31 ± 0.59b	91.35 ± 2.03a
ST (μm)	114.94 ± 1.03a	109.86 ± 1.50b	105.30 ± 1.83b
PT/ST	0.81 ± 0.01b	0.78 ± 0.01b	0.89 ± 0.03a
S_D (mm²)	198.56 ± 4.20c	501.00 ± 11.17b	810.99 ± 15.32a
l (μm)	17.99 ± 0.32a	11.74 ± 0.15b	10.22 ± 0.18c
w (μm)	11.06 ± 0.20a	7.77 ± 0.12b	6.40 ± 0.15c
A_s (μm²)	620.44 ± 13.98a	345.26 ± 5.02b	243.17 ± 5.66c
A_t (%)	11.07 ± 0.28c	18.09 ± 0.33b	21.03 ± 0.50a

Mean ± SE (n = 50) LT, leaf thickness; CT, cuticle thickness; ET_ad, adaxial epidermis cell thickness; ET_ab, abaxial epidermis cell thickness; PT, palisade tissue thickness; ST, spongy tissue thickness; PT/ST, ratio of palisade and spongy tissue; S_D, stomatal density; L, stomatal length; W, stomatal width; A_s, stomatal apparatus area; A_t, total stomatal apparatus area percent. Different letters in the same row indicate statistical difference (p < 0.05).