Gamma Rays and CarbonIon-Beams Irradiation for Mutation ...

esearch is aiming at finding out the following objectives: 1) to identify the
critical ion-beams doses; 2) to induce genetic variability for mutant
selection and; 3) to evaluate the response of black Sigatoka disease on the
irradiated plants.
4. 2. Materials and Methods
4. 2. 1. Assessment of banana explants in laboratory conditions
4. 2. 1. 1. Cultivars of banana
In this study, cultivars ‘Williams’ and ‘Cavendish Enano’ were
irradiated on June 6, 2005. The second irradiation was conducted for
‘Williams’, ‘Orito’ and ‘FHIA-01’, on November 14, 2005
4. 2. 1. 2. Explants slicing conditioning for ion-beams irradiation
For irradiation, banana explants as thin as 2 mm were requested
to allow entire penetration of the ion beam. Prior to irradiation, from April
28 to May 10, 2005, an experiment was conducted to clarify the
regeneration rate of the thinner banana explants. Cultivars ‘FHIA-01’ and
‘Williams’ were used. Two types of slicing or cutting methods were
applied to the banana corms shoot tips (both vertical and horizontal slices).
The slices were placed in liquid medium for regeneration, containing MS
medium, supplemented with BA (5 mg L -1 ), and sucrose (20 g L -1 ), at pH
5.6. Twenty-five slices were placed into a 300 mL Erlenmeyer flask
containing 100 mL of medium. Five flasks (replications) containing
‘Williams’ and ‘FHIA-01’ explants were prepared. The explants were
stirred in a shaker at 100 rpm. Regeneration rate and weight of explants
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