福岡県農業総合試験場研究報告

暖地の普通期水稲における被覆尿素による育苗箱全量施肥の実用性

荒木雅登・兼子　明^１）・井上恵子・末信真二^２）
（生産環境研究所）

［摘要］現在流通している被覆肥料の中で最も初期の窒素溶出抑制能力の優れた被覆尿素を用いて、暖地での水稲品種‘ヒノヒカリ’の普通期栽培における育苗箱全量施肥の実用性を明らかにした。
１　本田施肥量の25～35％を減肥して育苗箱施肥を行っても、慣行施肥法の95％～113　％の収量が得られ、品質についても遜色なかった。
２　しかし、育苗期間中の気象条件により被覆尿素の窒素溶出パターンが異なり、温度が　高い場合に苗が徒長したり、マット形成が不十分になる危険性があった。以上のことか　ら、現状では本施肥技術の実用性は低いと考えられた。

［キーワード：水稲、普通期、被覆尿素、育苗箱全量施肥、暖地］

　Practicability of a Single Application of Fertilizer in Nursery Boxes Using Coated Urea for the Normal Season Culture of Rice Plants in the Kyushu Region. ARAKI Masato, Akira KANEKO, Keiko INOUE and Shinji SUENOBU (Fukuoka Agriculutural Research Center, Chikushino, Fukuoka 8188549, Japan) Bull. Fukuoka Agric. Res. Cent. 18: 17 20 (1999)

　Research was conducted on the practicability of a single application of fertilizer in nursery boxes for the rice cv. Hinohikari for the normal season culture in the Kyushu region using coated urea whose control of nitrogen elution during the early days is most effective and widely used.

1　The same amount of yield was attained by a single application of fertilizer in nursery boxes using coated urea even though a reduction of about 25 - 35% of the standard total application rate of nitrogen fertilizer was realized.

2　However, this culture had a high risk of deteriorating seedling quality depending on the weather conditions because the coated urea solubility was influenced by the soil temperature.

From the above results, it's difficult to make the culture practical.

[Key Words: coated urea, Kyushu region, normal season culture, rice, single application of fertilizer in nursery boxes]