Capitula

Stems

Common receptacle

PG

WS

Cortex

Pith

Cortex

Secondary phloem

FC

Density (N˚/mm²)

8.8 ± 1.3a^*

13.2 ± 1.2a

5.9 ± 0.9b

13.8 ± 0.8a

57.1 ± 4.6c

Diameter (μm)

131.4 ± 12.1a^*

39.5 ± 2.9b

25.6 ± 1.3c

165.5 ± 18.6a^*

58.9 ± 9.5b

FO

Density (N˚/mm²)

34.7 ± 2.2a

15.5 ± 0.4b

5.5 ± 0.3c

12.2 ± 1.0b

45.2 ± 2a

Diameter (μm)

78.6 ± 1.6a

31.3 ± 2.8b

17.5 ± 1.8c

89.1 ± 7.2a

53.9 ± 3.1d