1 Citation 171 Views 12 Downloads
Radiation-contaminated soils are widespread around the Fukushima Daiichi
Nuclear Power Plant, and such soils raise concerns over its harmful effect
on soil-dwelling organisms. We evaluated the effects of contaminated soil
and moss sampled in Fukushima on the embryogenesis and hatching of aphid
eggs, along with the measurement of the egg exposure dose. Cs-137
concentration in soil and moss from Fukushima ranged from 2200 to 3300
Bq/g and from 64 to 105 Bq/g, respectively. Eggs of the eriosomatine aphid
Prociphilus oriens that were collected from a non-contaminated area were
directly placed on the soil and moss for 4 or 3 months during diapause and
then incubated until hatching. The total exposure dose to the eggs was
estimated as ca. 100–200 mGy in the 4-month soil experiment and 4–10 mGy
in the 4-month moss experiment. There was no significant difference in egg
hatchability between the contaminated soil treatment and the control. No
morphological abnormalities were detected in the first instars that
hatched from the contaminated soil treatment. However, we found weak
effects of radiation on egg hatching; eggs placed on the contaminated moss
hatched earlier than did the control eggs. On the contaminated soil, the
effects of radiation on egg hatching were not obvious because of
uncontrolled environmental differences among containers. The effects of
radiation on egg hatching were detected only in containers where high
hatchability was recorded. Through the experiments, we concluded that the
aphid eggs responded to ultra-low-dose radiation by advancing
embryogenesis.
171 views reported since publication in 2017.