Rootstock plant age

1-year-old

3-year-old

Needles anatomical characteristics

Mesophyll width (µm)

181.3 ± 20.7 (a)

76.6 ± 7.6 (b)

Epidermis width (µm)

18.6 ± 1.9 (a)

16.2 ± 2.3 (b)

Hypodermis width (µm)

0.03 ± 0.04 (b)

15.7 ± 1.9 (a)

% Vascular cylinder

14.5 ± 0.5 (b)

41.6 ± 0.4 (a)

Resin canal (µm2)

2013.0 ± 235,4 (b)

2741.7 ± 763.6 (a)

Stems anatomical characteristics

Total diameter (µm)

2355.6 ± 209.2 (b)

3717.5 ± 170.7 (a)

Xylem diameter (µm)

461.7 ± 74.2 (b)

811.4 ± 13.4 (a)

Phloem diameter (µm)

119.6 ± 10.2 (a)

149.1 ± 12.0 (a)

Periderm width (µm)

81.5 ± 8.5 (b)

117.5 ± 1.3 (a)

Rooting capability

% of rooting

96.66 ± 1.44 (a)

18.81 ± 0.98 (b)