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

Summary
Both Gamma rays and Carbon ion-beams irradiation methods were
applied in order to identify the critical irradiation doses, to induce genetic
variability for mutant selection and to evaluate the response of black Sigatoka
disease. Both irradiation methods acted different in terms of biological effect
when banana explants were exposed. Gamma rays and Carbon ion-beams
produced the same tendency of survival rate, meaning that increasing dosage
also increased mortality, but both methods were different in terms of linear
energy transfer. ‘FHIA-01’ tolerated high doses of Gamma rays, but was
susceptible to the high doses of Carbon ion-beams. The Gamma rays results
suggested that ‘FHIA-01’ can be explored using other dose intervals among
150 Gy and 500 Gy. Weight and height of plantlets were affected by Gamma
rays and Carbon ion-beams. Gamma rays reduced drastically these characters
when doses of 200-300 Gy were applied. Carbon ion-beams also affected the
height and weight with the doses between 4 and16 Gy. LD50 of both cultivars
‘FHIA-01’ and ‘Orito’ manifested high sensitivity to both Gamma rays and
Carbon ion-beams, although in each irradiation method the Gy energy were
different.
During the second Carbon ion beam irradiation the explants
behaved different. Weight and height remained stable up to 8 Gy and the
survival rate was reduced much more between 8 to 16 Gy.
The relative DNA content of ‘FHIA-01’ was reduced by Gamma
rays at 200 and 300 Gy, suggesting DNA deletion. ‘FHIA-01’ is definitely a
promising cultivar with high sensitivity response to Gy exposure with a high
chance of improving its quality by mutation induction. Sigmoid drooping leaf,
a putative mutation of ‘FHIA-01’ was generated. As first and second
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