. 2021 Oct 27;9:e12399. doi: 10.7717/peerj.12399

Table 3. Morphological characteristics and SPAD values.

Characteristics	Tetraploid	Mixoploid	Octoploid
Leaf thickness
Leaf thickness (µm) ± SE	160.8 ± 38.5^a	197.0 ± 8.7^ab	247.2 ± 15.0^b
Midrib vertical thickness (µm) ± SE	666.6 ± 25.0^a	762.4 ± 38.1^ab	831.7 ± 61.7^c
Midrib horizontal thickness (µm) ± SE	616.2 ± 42.1^a	793.0 ± 48.5^b	899.1 ± 56.0^b
Stomata and trichome
Stomata density (mm⁻²) ± SE	426.7 ± 9.4^b	298.2 ± 6.3^a	301.8 ± 10.9^a
Trichome density (mm⁻²) ± SE	33.9 ± 4.0^b	4.9 ± 2.0^a	4.9 ± 2.7^a
Stomata length (µm) ± SE	25.3 ± 0.2^a	29.3 ± 0.3^b	30.7 ± 0.3^c
Stomata width (µm) ± SE	14.9 ± 0.2^a	16.1 ± 0.2^b	16.6 ± 0.2^b
Stem cross-section
Bark (mm) ± SE	0.4 ± 0.1^a	0.4 ± 0.1^a	0.3 ± 0.0^a
Wood (mm) ± SE	3.1 ± 0.3^a	3.7 ± 0.3^a	3.8 ± 0.3^a
Pith (mm) ± SE	5.7 ± 0.3^b	5.2 ± 0.1^b	3.6 ± 0.2^a
SPAD value
SPAD ± SE	37.1 ± 1.0^a	37.2 ± 0.4^a	39.7 ± 0.6^b

Notes.

For each parameter, means with different letters indicate significantly different at 5% level of probability using Duncan’s test (p < 0.05).