経済的立地限界の茶栽培

日本作物学会紀事

平井 英明¹  付 杰奇²  星野 幸一¹  加藤 秀正¹  長 真弓³ 

[1] 宇都宮大学農学部;東京農工大学大学院連合農学研究科;荒井食品株式会社

关键词: 15N tracer;    15Nトレーサー;    Tea cultivation at the northern limit;    北限の茶栽培;    Uptake rate of the chemical fertilizer nitrogen;    窒素の利用率;   

DOI  :  10.1626/jcs.77.306

学科分类：农业科学（综合）

来源: Nihon Sakumotsu Gakkai / Crop Science Society of Japan

【 摘 要 】

In order to evaluate the rate of uptake of chemical fertilizer nitrogen by the young tea plants, after application at four seasons in Daigo-machi of Okukuji district, Ibaragi prefecture, 15N tracer experiments were performed with the pot-vegetation test, in the experimental farm, Utsunomiya University where precipitation and temperature are similar to those in Daigo-machi, Ibaragi. The uptake rate of the chemical fertilizer nitrogen applied in the summer, autumn, spring, and the bud break season was estimated to be 20.3%, 36.5%, 40.8%, and 46.4%, respectively. The rate of uptake by the young tea plants of the chemical fertilizer nitrogen in the second year was 28% when the standard application practice recommended by Ibaragi prefecture was implemented, while it was 44% when frequent split application from summer through autumn was implemented. However, the experiment was conducted under the abnormally cold condition in the winter when there were no mature leaves. Therefore, the uptake rates of nitrogen fertilizer applied by standard and split application method would be estimated to be around 35% and 55%, respectively, if the weather condition in the winter was normal. The split fertilization from summer through autumn improved storage of the fertilizer nitrogen in the nutrient storage organs such the mature leaves, stems, and roots, resulting in the increase in the plant growth. As a measure to suppress the marked decrease in available nitrogen from the second tea season through the autumn fertilization period in the Daigo-machi, frequent split application of chemical fertilizer in the summer and the autumn would be useful.

【 授权许可】

Unknown