질소(窒素) 시용시기별(施用時期別) 질소흡수율(窒素吸收率)과 수도체내(水稻體內)의 분포(分布)에 관한 연구(硏究)

The effect of application time of fertilizer nitrogen on its uptake rate and distribution in rice plant

수도(水稻)에 대한 질소질비료(窒素質肥料)의 분시효과(分施効果)와 시용시기(施用時期)에 따른 비료(肥料)의 흡수율(吸收率)과 흡수(吸收)된 비료(肥料)의 수도체내(水稻體內)에서의 분포(分布)를 조사(調査)키 위하여 정보당(町步當) 10kg의 질소질비료(窒素質肥料)를 전양기비(全量基肥)와 생육시기(生育時期)에 따라 4회(回)에 나누어서 분시(分施)한 시험결과(試驗結果)는 다음과 같다. 사용한 질소질비료(窒素質肥料)는 중질소(重窒素)로 표식(標識)된 유산암모니아를 사용(使用)한 시험결과(試驗結果)이다. 1. 질소질비료(窒素質肥料)의 분시효과(分施效果)가 컸다. 질소전량기비구(窒素全量基肥區)의 해미(亥米) 수량(收量) 3.1 ton/ha에 대하여 분시구(分施區) 3.4 ton/ha이었고 질소결제구(窒素缺制區)는 1.9ton/ha었다. 2. 수당입수(穗當粒數)와 천입중(千粒重)은 분시구(分施區)가 높았고 주당수수(株當穗數)와 등숙비(登熟比)는 전량기비구(全量基肥區)가 높았다. 3. 기비(基肥), 1차추비(追肥), 2차추비(追肥)와 3차추비(追肥)로 시용(施用)한 질소질비료(窒素質肥料)의 흡수율(吸收率)은 각각 28%, 33%, 51%와 63%였다. 4. 경엽중(莖葉中)에 함유(含有)되었던 질소(窒素)가 출수(出穗)이후 이삭 부분으로 이동(移動)되며 지엽발생기(止葉發生期)에 시비(施肥)한 질소(窒素)가 제일 많이 이삭쪽에 분포(分布)되었다.

A study was carried out to investigate the effect of application time of fertilizer nitrogen on its rate of uptake and its distribution in rice plant. The rate of applied fertilizer was 100kg/ha, as a single application at transplanting time and four equal split applications of 25kg/ha was applied at transplanting time, 3 weeks after transplanting, 1 week before the primodial initiation stage of growth and at the flag leaf stage of growth, respectively. The ammonium sulfate was labelled with N-15, as 1% atom excess for single application and 4.4% atom excess for split applications. The results are sumarized as follows: 1. The effect of split application of nitrogen on yield was observed. The yield of brown rice of the single application at transplanting time was 3.1 ton/ha and the split application was 3.4 ton/ha. However, without nitrogen the yield was reduced to 1.9 ton/ha. 2. The number of grains per panicle and 1000 grains weight were increased as split application of nitrogen, but for the number of panicles per hill and maturing rate, the single application of nitrogen revealed favorable results. 3. The rate of uptake of applied fertilizer nitrogen showed a tendency that the efficiency of fertilizer nitrogen increased by top dressing. The rate of uptake of applied nitrogen as basal application, first top dressing, second top dressing and third top dressing was 28%, 33% 51% and 63%, respectively. 4. After shooting stage of the growth, nitrogen in straws transfered to grains. The nitrogen applied at flag leaf stage was absorbed by root and easily accumulated in grains rather than straw.