الفهرس 
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Abstract
In vitro mass propagation of banana (Musa spp.) cv. Grand Naine was
carried out. Produced 40000 vitroplants were screened for somaclonal variations
during acclimatization, nursery and open field stages. Shoot tip explants were
cultured on Murashige and Skoog 1962 (MS) basal medium supplemented with
BA (3.0 mg/l), sucrose (30 g/l) and solidified with gelrite (2.0 g/l). Axillary buds
were proliferated in vitro through two recultures. Cultures were multiplied for
18 weeks (6 subcultures) on the same medium but solidified with phyto-agar
(5.5 g/l). In rooting stage, Separated shoots were cultured on MS medium
contained IBA (1.0 mg/l), sucrose (30 g/l) and solidified with phyto-agar (6.5
g/l). Screening detected 1800 morphological malformed plantlets after 6 weeks
in acclimatization, these malformed plantlets were grouped into 12 off-types.
Some of them (3 off-types) were reverted and another one was died later in the
nursery. However, some abnormal plants (8 off- types) were newly appeared
after 6 months in the nursery. Finally, 3 off-types were reverted and another one
was died in the open field.
Open field survey detected 5 new off-types. Generally in all stages, the
total detected variants were 3098 (7.75 %); 1000 plants of them (2.5%) were
reverted and 202 plants (0.5%) were died. Results revealed that most of the
variants can be screened out at the nursery stage; the remaining off-types (1.28
%) were detected only in the open field. Open filed growth parameters such as
pseudostem height and circumference, leaf orientation, length, width and area
were measured. Also, Pigmentation in the leaf and the stem were evaluated.
Moreover, bunch weight, height, circumference, number of hands and fingers
per hand were recorded as reproductive parameters.
Random Amplified Polymorphic DNA (RAPD) was carried out to study
the differences among the cv. Grand Naine and its 23 somaclones using
seventeen arbitrary primers. The PCR products gave 1864 amplified fragments.
According to cluster analysis ’winged petiole’ and ’deformed lamina’ were more
related to the normal plant. However, ’Giant plant’ and ’weak plant’ related to
each other and clustered with normal plant. According to principal coordinate
analysis most of the variants were aggregated nearly whereas ’variegated plant’
was separated apart from the other variants. Which, may reflect the genetic
difference between variegated plant and other somaclonal variants.