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

deletion rather than point mutation, resulting in producing characteristics
mutant induced by ion-beams. However, the characteristics of ion-beams
on mutation induction have not been clearly elucidated yet.
Using the carnation variety ‘Vital’ Okamura et al. (2003)
obtained a wide mutation spectrum in flower color and shapes compared
with gamma rays application. Commercial cultivars were released in the
spring 2002 in Japan from these mutants named as ‘Red Vital Ion’, ‘Dark-
Pink Vital Ion’ and ‘Misty Vital Ion’, expecting an economic impact of
about 10 billion yen.
Concerning to genetic improvement of banana, different
techniques have been applied. Using gamma rays as mutagen, FAO/IAEA
(2006) reported a banana mutant named ‘Klue Hom Thong KU1’ in
Thailand, where the main improved characteristic was the bunch size and
cylindrical shape. Roux (2001) mentioned that other desirable variants and
putative mutants of banana have been identified for release or further
confirmation trials in several countries. Cuba obtained the ‘SH-3436-L9’
and ‘6.44’ mutants by gamma rays having a height reduction from the
original plant. In Malaysia, both cultivars ‘Mutiara’ and ‘Novaria’ are
tolerant to Fusarium oxisporium, obtained by somaclonal variation. Height
reduction and large fruit size of selections ‘LK-40’ and ‘LT-3’, respectively,
were found in Philippines by using gamma rays. In Sri Lanka, ‘Embul-35
Gy’ showed earliness by using gamma rays. IAEA also reported that
‘GN35-I to GN35-VIII’ were selected clones derived from the ‘Grand
Naine’ tolerant to toxin of M. fijiensis by using gamma rays.
In banana, induced mutation technique by ion-beams has not
been reported. In the present study, the ion-beams mutation induction
technique was applied to study the effect of irradiation doses on banana
explants and regenerated plantlets to black Sigatoka disease reaction. This
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