著者

Hiromi NAKANISHI Atsushi MORI Kouki TAKEDA Houdo TANAKA Natsuko KOBAYASHI Keitaro TANOI Takashi YAMAKAWA Satoshi MORI

出版者

日本学士院

雑誌

Proceedings of the Japan Academy, Series B (ISSN:03862208)

巻号頁・発行日

vol.91, no.4, pp.160-174, 2015-04-10 (Released:2015-04-10)

参考文献数

34

被引用文献数

3 14

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Six months after the explosion of TEPCO’s Fukushima Dai-ichi nuclear power plant, radioactive silver (110mAg), was detected in concentrations of 3754 Bq/kg in Nephila clavata (the orb-web spider; Joro-gumo in Japanese) collected at Nimaibashi, Iitate village in Fukushima Prefecture, whereas 110mAg in the soil was 43.1 Bq/kg. A survey of 35 faunal species in the terrestrial environment during the 3.5 years after the accident showed that most of Anthropoda had two orders higher 110mAg in their tissues than soils, although silver is not an essential element for their life. However, tracing of the activity of 110mAg detected in spider Atypus karschi collected regularly at a fixed location showed that it declined much faster than the physical half-life. These results suggest that 110mAg was at once biologically concentrated by faunal species, especially Arthropoda, through food chain. The factors affecting the subsequent rapid decline of 110mAg concentration in faunal species are discussed.

著者

Yusaku Noda Ryohei Sugita Atsushi Hirose Naoki Kawachi Keitaro Tanoi Jun Furukawa Ken Naito

出版者

Japanese Society of Breeding

雑誌

Breeding Science (ISSN:13447610)

巻号頁・発行日

vol.72, no.4, pp.326-331, 2022 (Released:2022-11-05)

参考文献数

16

被引用文献数

6

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Wild species in the genus Vigna are a great resource of tolerance to various stresses including salinity. We have previously screened the genetic resources of the genus Vigna and identified several accessions that have independently evolved salt tolerance. However, many aspects of such tolerance have remained unknown. Thus, we used autoradiography with radioactive sodium (22Na+) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to visualize and compare Na+ allocation in Vigna angularis (Willd.) Ohwi & H.Ohashi (azuki bean), Vigna nakashimae (Ohwi) Ohwi & H.Ohashi, Vigna riukiuensis (Ohwi) Ohwi & H.Ohashi, Vigna luteola (Jacq.) Benth. and Vigna marina (Burm.) Merr.. The results indicated: 1) Tolerant accessions suppress Na+ accumulation compared to azuki bean. 2) V. nakashimae and V. marina does so by accumulating higher amount of K+, whereas V. riukiuensis and V. luteola does so by other mechanisms. 3) V. luteola avoids salt-shedding by allocating excess Na+ to newly expanded leaves. As the mechanisms of the tolerant species were different, they could be piled up in a single crop via classical breeding or by genetic engineering or genome editing.

著者

Yusaku Noda Ryohei Sugita Atsushi Hirose Naoki Kawachi Keitaro Tanoi Jun Furukawa Ken Naito

出版者

Japanese Society of Breeding

雑誌

Breeding Science (ISSN:13447610)

巻号頁・発行日

pp.22012, (Released:2022-08-30)

被引用文献数

6

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Wild species in the genus Vigna are a great resource of tolerance to various stresses including salinity. We have previously screened the genetic resources of the genus Vigna and identified several accessions that have independently evolved salt tolerance. However, many aspects of such tolerance have remained unknown. Thus, we used autoradiography with radioactive sodium (22Na+) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to visualize and compare Na+ allocation in Vigna angularis (Willd.) Ohwi & H.Ohashi (azuki bean), Vigna nakashimae (Ohwi) Ohwi & H.Ohashi, Vigna riukiuensis (Ohwi) Ohwi & H.Ohashi, Vigna luteola (Jacq.) Benth. and Vigna marina (Burm.) Merr.. The results indicated: 1) Tolerant accessions suppress Na+ accumulation compared to azuki bean. 2) V. nakashimae and V. marina does so by accumulating higher amount of K+, whereas V. riukiuensis and V. luteola does so by other mechanisms. 3) V. luteola avoids salt-shedding by allocating excess Na+ to newly expanded leaves. As the mechanisms of the tolerant species were different, they could be piled up in a single crop via classical breeding or by genetic engineering or genome editing.

著者

Mamoru Sato Kaori Matsuoka Tsugiko Takase Natsuko I. Kobayashi Hidetoshi Kikunaga Daisuke Takata Keitaro Tanoi Tsutomu Ohtsuki Shinnosuke Kusaba Katsuhiko Yamaguchi

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-006, (Released:2019-01-18)

被引用文献数

8

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We investigated the vertical 137Cs distribution in soil among five sod culture orchards with different soil textures over six years after 2011, when 137Cs fallout was released by the Fukushima Daiichi Nuclear Power Plant accident, to confirm the long-term 137Cs downward-migration into soil. At each orchard, soil cores were collected to a depth of 30 cm and subdivided into intervals of 3 to 9 cm. The 137Cs within the 3 cm of topsoil decreased from 84–94% during the first 7 months after deposition in 2011 to 41–75% in 2017. From 2012 onward, the vertical 137Cs profiles in the soils were explained by a two-component negative exponential model composed of a rapid and a slow component with a change of slope at a depth of 6 to 9 cm. It took 4 years after deposition to show a significant difference in the value of the average 137Cs migration distance (Md) among the orchards. The speed of 137Cs migration in the orchards during the 6 years after the accident year was 0.44 to 0.97 cm year−1 based on the Md. There was a significant positive correlation between Md and fine sand content in the 3 cm of topsoil between Md and the ratio of the total carbon content (TC) at a depth of 3 to 6 cm to that in the top 3 cm of soil. Furthermore, the percentage of exchangeable 137Cs (ex-137Cs) to 137Cs at 3 to 6 cm depth increased significantly in proportion to the ratio of TC at 3 to 6 cm depth to TC at 0 to 3 cm depth in soil collected in 2013. These findings indicate that one of the mobile forms of 137Cs was ex-137Cs combined with TC and that the fine sand content and TC influenced the 137Cs downward-migration in the 3 cm of topsoil in the orchard in which organic matter accumulated by sod culture.

著者

Toshinori ARAMAKI Ryohei SUGITA Atsushi HIROSE Natsuko I. KOBAYASHI Keitaro TANOI Tomoko M. NAKANISHI

出版者

公益社団法人 日本アイソトープ協会

雑誌

RADIOISOTOPES (ISSN:00338303)

巻号頁・発行日

vol.64, no.3, pp.169-176, 2015-03-15 (Released:2015-03-28)

参考文献数

23

被引用文献数

3 14

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We performed an imaging analysis of 42K in Arabidopsis using real-time radioisotope imaging system(RRIS). First, we purified 42K from an 42Ar―42K generator. And then, we characterized RRIS performance by quantitatively determining 42K using standard series. As a result, the dynamic range for 42K was determined to be at least three orders of magnitude. Next, we evaluated the level of self-absorption in Arabidopsis organs by comparing the signal intensity detected using RRIS and the actual radioactivity detected by a gamma-counting method. There was no significant difference in detection efficiency between the thick bolt(stem) tissue and the thin leaf tissue. The reason for scarce self-absorption could be related to the relatively strong β ray emissions that have a maximum energy of 3525.4keV.