@article{oai:repository.naro.go.jp:00001688,
 author = {菊地, 直 and KIKUCHI, Sunao and 保科, 次雄 and HOSHINA, Tsuguo and 木村, 武 and KIMURA, Takeshi and 宮地, 直道 and MIYAJI, Naomichi and 山崎, 浩道 and YAMAZAKI, Hiromichi and 梅宮, 善章 and UMEMIYA, Yoshiaki and 木嶋, 伸行 and KIJIMA, Nobuyuki},
 journal = {野菜茶業研究所研究報告, Bulletin of the National Institute of Vegetable and Tea Science},
 month = {Mar},
 note = {Growth and nitrogen content were different among nine tomato cultivars grown under three nitrogen levels (50,100,150mg-NIL). Applied nitrogen efficiency to growth was highest in 'Odoriko', and lowest in 'June Pink'. It was suggested that the difference in tomato growth was influenced not only by the difference of nitrogen uptake but also the difference of nitrogen efficiency ratio (dry weight per nitrogen content). A positive correlation between the tomato growth and the content of assimilated nitrogen was observed. Therefore, it was suggested that the ability of nitrogen assimilation was different among the cultivars, and that the difference in ability of nitrogen assimilation influenced the difference in the nitrogen efficiency ratio and growth. We compared 'Odoriko' and 'June Pink' for nitrate (N0_3^-) reduction, which is the most important step in nitrogen assimilation. It was shown that there were differences of nitrate reductase (NR) activity and rate of nitrate assimilation between the two cultivars. We analyzed the kinetic properties of NO_3^- influx on high/low-affinity transport systems (HATS and LATS), and on the responses of net uptake, influx and efflux to external N0_3^- of pretreatments on LATS to clarify the N0_3^- uptake characteristics of the two cultivars. The Vmax value on HATS and the slope of influx on LATS in 'Odoriko' were higher than in 'June Pink'. These results suggested that 'Odoriko' had a greater ability of N0_3^- influx. The rates of decline on net uptake were different between the two cultivars in the experiment for analysis of the effects of pretreatment to N0_3^- net uptake on LATS. The rate of net uptake declined remarkably on 'June Pink' more than on 'Odoriko', especially in the 4 mM N0_3- treatment. In order to clarify the mechanism for the deference in the effect on net uptake, we analyzed the effects of pretreatment to influx and efflux. The decline of influx on LATS was not shown in either cultivar. On the other hand, the efflux rates of 'June Pink' were higher than of 'Odoriko' in each of the treatments, and the differences in the efflux rate were extended with increased NO_3^- concentration in the pretreatments. These results indicated that the higher efficiency of NO_3^ -N utilization on 'Odoriko' was due to the lower efflux rate and the higher net uptake with high external NO_3^- levels. It was presumed that higher NR activity and ability of nitrate reduction on 'Odoriko' caused the lower efflux on 'Odoriko', and the extending of the difference on efflux at higher external NO_3^- levels.},
 pages = {109--119},
 title = {トマト幼苗の施肥窒素に対する生育反応および窒素利用における品種特性の解析},
 volume = {8},
 year = {2009},
 yomi = {キクチ, スナオ and ホシナ, ツグオ and キムラ, タケシ and ミヤジ, ナオミチ and ヤマザキ, ヒロミチ and ウメミヤ, ヨシアキ and キジマ, ノブユキ}
}