JAEA-Review-2010-065.pdf:15.99MB - 日本原子力研究開発機構

Effect of Ion Beam Irradiation for Asclepias Species
N. Kobayashi a) , S. Sasaki a) , K. Tasaki a) , A. Nakatsuka a) ,
S. Nozawa b) , Y. Hase b) and I. Narumi b)
a) Faculty of Life and Environmental Science, Shimane University,
b) Radiation-Applied Biology Division, QuBS, JAEA
1. Introduction
Asclepias is one of the perennial ornamentals native to
Central America, using for cutting, potting and bed flowers.
For the purpose to obtain flower and/or plant form
mutation 1–2) , Asclepias curassavica seeds were irradiated
by ion beams and researched its effect 3–5) . In this study
using A. incarnara L. and A. tuberosa, the seed
germination rates, growth and survival rate of seedlings
obtained from ion beam irradiated seeds are investigated.
2. Materials and Methods
Asclepias incarnara L. and A. tuberosa L. were
irradiated with carbon ion beams (220 MeV 12 C 5+ ) at 12.5,
25, 50, 100 and 150 Gy on September 2009 and at 30, 45,
60, 75 and 90 Gy on October 2009.
Irradiated seeds were sowed in a green house and
germinated seedlings were transplanted into pots.
Germination rate was investigated on 20 days after
germination. Leafing and survival rate were investigated
on 30 and 40 days after germination, respectively.
3. Results and Discussion
Seed germination rate decreased from 100 Gy irradiation
Rate (%)
Rate (%)
100
80
60
40
20
0
100
80
60
40
20
3-11
0
with increasing doses and any seeds could not germinate in
150 Gy for both Asclepias species. Survival rate of
seedlings decreased below 50% of lethal rate in more
50 Gy (Fig. 1 upper). Rate of germination becomes 50%
between 75 to 90 Gy for A. incarnate and between 60 to
90 Gy for A. tuberosa in November (Fig. 1 lower) and
these seedlings could not survive because of their
dormancy phase at low temperature. In the case of A.
curassavica seed, irradiation of 50 to 200 Gy was optimal 5) .
It is needed to consider the optimal irradiation dose and life
cycle to get mutants for these species.
References
1) N. Kobayashi et al., JAEA Takasaki Ann. Rep. 2006
(2008) 87.
2) N. Kobayashi et al., JAEA Takasaki Ann. Rep. 2007
(2008) 70.
3) S. Kano et al., Abst. Chugoku-Shikoku Br., Japan. Soc.
Hort. Sci. 46 (2007) 40.
4) S. Kano et al., Hort. Res. 7 (Suppl. 2) (2008) 583.
5) N. Kobayashi et al., JAEA Takasaki Ann. Rep. 2008
(2009) 77.
A. incarnata A. tuberosa
Germination rate
Survival rate
12.5 25 50 100 150
30 45 60 75 90
JAEA-Review 2010-065
Rate (%)
Fig. 1 Effects of ion beam irradiation for seed germination and survival rates in Asclepias. A. incarnate (left) and
A. tuberosa (right). Data are from irradiation in September (upper) and October (lower).
Rate (%)
100
80
60
40
20
0
100
80
60
40
20
0
Germination rate
Survival rate
12.5 25 50 100 150
30 45 60 75 90
Absorbed dose (Gy) Absorbed dose (Gy)
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