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

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disturbing other characters of variety (Morishita et al., 2001). The difficulties associated with conventional breeding led to the exploration of other techniques for introducing useful characteristics into otherwise reliable clones. Mutations can be induced with chemicals, irradiation and also by in vitro tissue culture. The strategy is not without difficulties of a practical nature as it involves the production and subsequent growth and observation of large numbers of individual plants from which selections are made (FAO, 2001a). Van Harten (1998) defines mutation in higher plants as, any heritable change in the idiotypic constitution of sporophytic or gametophytic plants tissue, not caused by normal genetic recombination or segregation. Mutagenesis is also defined as the process of mutation formation at the molecular levels. Spontaneous mutation can occur without intentional human intervention as a result from the activity of so-called transposons (mobile genetic elements that can move within the genome, from one place to another and affect the activity of the gene which they are inserted). A tobacco mutant cultivar ‘Chlorina’, which became the first radiation-induced mutant cultivar in the world, was grown from 1936 in Indonesia since it had been released. It is often found that induced mutations may occur in frequencies of 10 3 higher than spontaneous mutations. Moreover, it is mentioned that even though mutagenesis have been occurred a long time ago in a plant, but those remained unobserved for some reason, at certain moment those may became visible, e.g. by a morphological change in a plant part, and then create the impression of a recent event. Another reason to consider using induced mutations is that breeding programmes could eventually be speeded up considerably. Irradiation of plant materials such as seeds, buds and plantlets with gamma rays or neutrons can introduce changes in DNA sequences and rearrangement of parts of chromosomes. These changes have resulted in a 13
large number of improved mutant crops demonstrating, disease resistance, early maturity, drought tolerance, and better yield. Over the past 60 years, 1,800 new mutant plant varieties induced by radiation have been officially released and are now growing on millions of hectares of land. In Japan, more than 10 years ago a mutant variety of Japanese pear ‘Nijisseiki’ was developed by low dose-rate gamma rays irradiation method. This new variety, named as ‘Gold Nijisseiki’ has an excellent resistance against black spot disease. By the FAO/IAEA laboratories and the member states such as Indonesia and Malaysia, mutant varieties of banana which are more resistant to plant disease (Fusarium) and higher yield are being developed by radiation mutation in combination with tissue culture techniques (Machi, 2002). In terms of radioactivity, the improved mutant crops obtained by gamma rays are not dangerous for consumption by human beings, and on the contrary, is useful even for production of safe food. Most food irradiation facilities utilize the radioactive element 60 Cobalt as a source of high energy gamma rays. These gamma rays have sufficient energy to dislodge electrons from some food molecules, thereby converting them into ions (electrically charged particles). Gamma rays do not have enough energy to affect the neutrons in the nuclei of these molecules; therefore, they are not capable of inducing radioactivity in the food. 60 Cobalt is usually the preferred source of radiation for food. Irradiation dosage is a function any energy of the radiation source dependent upon the time of exposure. Doses are usually expressed by kiloGrays (kGy); 1 Gray is equivalent to 1 joule of absorbed radiation/kg tissue (Doyle, 1999). As mentioned above, gamma rays at present are the most favored mutagenic agent, having no particles and electric charge. However, their great penetrating power makes them dangerous as they can cause considerable damage when they pass through the tissue. The distance 14
Page 1 and 2: Gamma Rays and Carbon Ion-Beams Irr
Page 3 and 4: Table of contents Chapter 1 1.1. In
Page 5 and 6: 4.2.1.1. Cultivars of banana……
Page 7 and 8: and ‘Valery’, which are exporte
Page 9 and 10: ‘Cavendish Enano’, ‘Williams
Page 11 and 12: Although it is now found only in Au
Page 13 and 14: varieties bred at the Jamaican prog
Page 15 and 16: such as ‘Paka’ (AA) and ‘Pisa
Page 17: Resistance (PR). In connection with
Page 21 and 22: which migrated faster (Rf = 0.44) t
Page 23 and 24: is juglone (5 hydroxy-1,4-napthoqui
Page 25 and 26: experiments involving various biolo
Page 27 and 28: Tanaka (1999) reported novel genes
Page 29 and 30: 2. 1. Materials and Methods Chapter
Page 31 and 32: 2. 1. 1. 4. FHIA-01 ‘FHIA-01’(M
Page 33 and 34: (Gamma room)” and “Carbon ion-b
Page 35 and 36: esulting from “Gamma Room” expe
Page 37 and 38: traits as female sterility and part
Page 39 and 40: 3. 2. 1. 3. Chronic irradiation ( 1
Page 41 and 42: Gy. ‘Williams’ and ‘Orito’
Page 43 and 44: a diploid clone (genomic constituti
Page 45 and 46: ‘Williams’ (93%), the necrotic
Page 47 and 48: etween the irradiation doses and th
Page 49 and 50: moment they are at the development
Page 51 and 52: A B C D Fig. 2. Cultivars of banana
Page 53 and 54: Weight of plantlets (g) Height of p
Page 55 and 56: Control 50 Gy 100 Gy 150 Gy Fig. 6.
Page 57 and 58: Control 50 Gy 100 Gy 150 Gy 200 Gy
Page 59 and 60: Survival rate (%) for LD50 Survival
Page 61 and 62: A B C D E F Fig. 12. A plant from
Page 63 and 64: B D AA E Fig 14. Banana meristems a
Page 65 and 66: A B C Orito Orito Orito Cavendish E
Page 67 and 68: No. plants No. plants No. plants No
Page 69 and 70:
Circunference (cm) Plant height (cm
Page 71 and 72:
Table 1. Differences of the plantle
Page 73 and 74:
Table 3. Differences of the surviva
Page 75 and 76:
Table 5. Selected materials reporti
Page 77 and 78:
Table 8. Factor of effectiveness an
Page 79 and 80:
deletion rather than point mutation
Page 81 and 82:
were recorded. From the results, th
Page 83 and 84:
4. 2. 2. Assessment of banana plant
Page 85 and 86:
placement among the plants (Fig. 30
Page 87 and 88:
hours, photographs of the leaf-disc
Page 89 and 90:
‘Williams’ (B) was obtained by
Page 91 and 92:
class limits values are clearly sep
Page 93 and 94:
values in ‘Cavendish Enano’ ran
Page 95 and 96:
Only a partial resistance was obser
Page 97 and 98:
Sigatoka but also fruit quality, po
Page 99 and 100:
A C Fig. 23. Banana plantlets packa
Page 101 and 102:
A C Fig. 25. Acclimatization of the
Page 103 and 104:
A C Fig. 27. Survival plantlets for
Page 105 and 106:
A C Fig. 29. Mycosphaerella fijiens
Page 107 and 108:
A C Fig. 31. Labor during transplan
Page 109 and 110:
B A Fig. 33. Establishment of the j
Page 111 and 112:
A B Fig. 35. Regenerated plantlets
Page 113 and 114:
Survival rate (%) for LD50 Survival
Page 115 and 116:
0 0.5 1 2 4 Fig 39. Banana plantlet
Page 117 and 118:
A B C Fig. 41. Regenerated explants
Page 119 and 120:
Range of optimum doses (Gy) 16 15 1
Page 121 and 122:
Percent of plants Percent of plants
Page 123 and 124:
LDNA-% LDNA-% DDP-days 100 80 60 40
Page 125 and 126:
Fig. 49. Hexaploid cells in ‘Cave
Page 127 and 128:
Table 10. Infection index (II-%), d
Page 129 and 130:
Table 12. DDP-days, II-% and LDNA-%
Page 131 and 132:
Chapter 5 General Discussion Gamma
Page 133 and 134:
FHIA-01 were not able to compare du
Page 135 and 136:
‘W 1 II 31’. In the case of ‘
Page 137 and 138:
Summary Both Gamma rays and Carbon
Page 139 and 140:
A ‘Cavendish Enano’ plant with
Page 141 and 142:
I extend my gratitude also to Dr. K
Page 143 and 144:
Cohan, J, P., C. Abadie, K. Tomekp
Page 145 and 146:
Hase, Y., M. Yamaguchi and A. Tanak
Page 147 and 148:
Molina, G. C. and J. P. Krausz (198
Page 149 and 150:
Roux, N. S. (2001). Mutation induct
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