Agriculture Reference
In-Depth Information
8
1 cm
7
(a)
6
5
4
3
4-8
3
4-8
2
2
4-8
3
2
2
1
1
1
1
Ø
0.2 cm
Ø
0.3 cm
Ø 0.8 cm
Ø 2.0 cm
350
(b)
Cortex
300
Perimedullary
Pith
250
200
150
100
50
0
0.2
0.3
0.8
1. 0
2.0
3.0
3.0
(c)
2.5
2.0
1. 5
1. 0
0.5
0.0
0.2
0.3
0.8
1. 0
2.0
3.0
Tuber diameter (cm)
Fig. 4.1.
(a) Schematic overview of the different growth stages during tuber formation. From left to right,
longitudinal cross sections of a non-tuberizing stolon 0.2 cm, swelling stolon 0.3 cm, small tuber 0.8 cm,
and larger tuber of 2 cm. The growth of the perimedullary region is indicated by the gray area, and nodes
are indicated numerically. (b) Number of cells along the transversal axis in non-tuberizing stolon (0.2 cm)
and large tuber (3 cm). (c) Thickness of the individual regions (cortex, perimedullary, and pith of tuber
developmental stages, as shown in (b)). (From Xu
et al.,
1998b.)
