Protocols for Micropropagation of Woody Trees and Fruits

PROPAGATION OF MONGOLIAN CHERRY AND NANKING CHERRY
P. ussuriensis, P. Americana, P. angustifolia, P. hortulana, P. maritime,
P. mexicana, P. munsoniana, P. nigra, P. rivularis, P. subcordata
– CERASUS (sweet and sour cherries): P. avium, P. cerasus, P. fruticosa,
P. japonica, P. maackii, P. mahaleb, P. pseudocerassus, P. pumila, P. serrulata,
P. tomentosa
– PADUS (bird cherries): P. padus, P. serotina
– LAUROCERASUS (bay-cherries).
2.4.2. Number of Chromosomes
In Prunus, the basic number in vegetative cells is eight chromosomes (Crane &
Lawrence, 1952; Iezzoni et al., 1991). Polyploidy, due to interspecific hybridization,
took place during the phylogeny of the genus and is responsible for self-sterility and
intersterility. Polyploidy is important since plants with this character are often very
vigorous and may posses a natural resistance to frost, diseases or insects. Among
cherries, the sweet (P. avium) and sour (P. cerasus), flowering ornamental cherries,
and the other that are used as rootstocks for cherries are important. The earliest
description of so called ‘keration’ (the name of the fruit, Ceratonia silqua or carobtree)
comes from Theophrastus about 300 B.C. Prunus fruticosa, the Mongolian cherry
(also called the ground cherry), is considered the most probable parent of both P.
avium and P. cerasus (Fogle, 1975).
The chromosome number of P. fruticosa is 2n = 32 (tetraploid) (Izzoni et al.,
1991). On the other hand, Prunus tomentosa is a diploid with the chromosome
number of 2n = 16 (Darlington & Janaki, 1945). For comparison, both Mongolian and
Nanking cherry are included in Table 6 which illustrates the chromosome numbers
for species classified in subgenus Cerasus.
Table 6. The number of chromosomes and degrees of ploidy for genus Cerasus.
Species Chromosome number Reference
Prunus avium 2n=16 (diploid), 24, 32
P. besseyi 2n=16 (diploid)
Darlington & Janaki, 1945
Bennett & Leitch, 1995
P cerasus 2n=32 (tetraploid) Missouri Bot. Garden, 1985;
Bennett & Leitch, 1995
P. fruticosa 2n=32 (tetraploid)
P. mahaleb 2n=16 (diploid)
Darlington & Janaki, 1945
P. pumila 2n=16 (diploid)
P. serrulata 2n=16 (diploid), 24
P. subhirtella 2n=16 (diploid)
P. tomentosa 2n=16 (diploid)
Darlington & Janaki, 1945
Darlington & Janaki, 1945
Darlington & Janaki, 1945
Bennett & Leitch, 1995;
Darlington & Janaki, 1945
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