著者

本多 [ヤスシ] 臼田 純雄

出版者

日本作物学会

雑誌

日本作物學會紀事 (ISSN:00111848)

巻号頁・発行日

vol.27, no.4, pp.429-431, 1959

被引用文献数

1

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I. Experiments were made on the rooting activity of rice seedlings grown in lowland nurseries of different sowing density, in 1956. Thinly sown seedlings attained greater height and larger top-weight, and developed more abundant roots, than thickly sown seedlings. Therefore, "aging" seemed to have progressed quicker in thickly sown seedlings. Chemical composition of the seedling shoots depended upon their rootage. Both total sugar and starch contents increased with the amount of root, which is in turn controlled by nitrogen content in the shoot. Thus, thinly sown seedlings retained juvelinity, and had high rooting ability as compared with that of upland nursery seedlings. II. Furhter experiments in 1957 were made using various fertilizers on characteristically young and aged seedlings. Best results were obtained by the seedlings grown with 2N fertilizer for 44 days. When nitrogen denominater in the ratio suger+starch/nitrogen of the content in seedling is abnormally high additional applications of straw ash, KC1 and (NH<SUB>4</SUB>)<SUB>2</SUB>SO<SUB>4</SUB> tended to improve the conditions and there were produced abundant roots. Rooting activity of seedlings were intensified by increasing the sum of total sugar+starch+nitrogen compounds caused by straw ash and KC1 applications, and on the other hand, by increasing total nitrogen in seedlings by means of addition of (NH<SUB>4</SUB>)<SUB>2</SUB>SO<SUB>4</SUB> fertilizer.