@article{oai:kagawa-u.repo.nii.ac.jp:00000516, author = {長谷川, 博 and Hasegawa, Hiroshi and 矢頭, 治 and Yatou, Osamu and 一井, 眞比古 and Ichii, Masahiko}, issue = {2}, journal = {育種学雑誌, Breeding science}, month = {Jun}, note = {A rice mutant hypersensitive to chlorate (an analog ion for nitrate), M605, was isolated from the mutant lines derived from a japonica cultivar, Norin 8. In this experiment, three biochemical steps of nitrate assimilation, i.e. nitrate uptake, nitrate reduction and nitrite reduction, were ana-lyzed using M605, Norin 8 and a chlorate hypersensitive indica cultivar, Leuang Tawng. Uptake ability of monova-lent anions including nitrate in M605 and Leuang Tawng was lower than that of Norin 8 except for chlorate uptake in M605. Chlorate uptake from a 200 /1 M potassium chlo-rate solution in M605 was 1.2 fold that in Norin 8. In both seedlings and roots of M605, activities of NADH-NR, NADPH-NR and NiR were similar to those of Norin 8. These results indicate that chlorate hypersensitivity in M605 may be due to the increased level of chlorate uptake. Genetic study showed that chlorate hypersensitivity in M605 was transmitted by polygenic factors. On the other hand, activities of leaf NRs and NiR of Leuang Tawng were twice to three times higher than those of Norin 8. There was no difference in the activities of root NRs and NiR between Leuang Tawng and Norin 8. It was suggested that the chlorate hypersensitivity in Leuang Tawng may be due to the higher activities of leaf NRs and NiR., 塩素酸イオンは植物の細胞毒であるが硝酸イオンのアナログとして挙動する.塩素酸に対する感受性を指標として植物の硝酸代謝能を評価することができる.本実験では農業生物資源研究所放射線育種場において保存されているイネ突然変異系統より塩素酸に高感受性を示す1系統M605を選抜し,その硝酸吸収能,硝酸還元酵素(NR)および亜硝酸還元酵素(NiR)活性を原品種である農林8号およびインド型品種Leuang Tawngと比較した.M605は農林8号に比べて硝酸吸収能が低下していたが,塩素酸吸収能は1.2倍に促進されていた.M605の葉と根におけるNRとNiR活性は共に農林8号と同レベルであった.これらの結果はM605の塩素酸高感受性が塙素酸吸収量の増加に起因することを示唆している.}, pages = {229--232}, title = {塩素酸吸収能が高く塩素酸高感受性を示すイネ突然変異体}, volume = {45}, year = {1995}, yomi = {ハセガワ, ヒロシ and ヤトウ, オサム and イチイ, マサヒコ} }