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作 者:徐季娥 林裕益[1] 吕瑞江[1] 陈良[2] 高占峰[2]
机构地区:[1]河北省农科院石家庄果树研究所,050061 [2]河北省农科院理化所,石家庄050051
出 处:《园艺学报》1993年第2期145-149,共5页Acta Horticulturae Sinica
基 金:河北省科学技术委员会资助项目
摘 要:以3年生初结果鸭梨/杜梨树为试材,采用田间微区法土施^(15)N-尿素,秋施的氮肥在年周期内均可为植株吸收,当年肥料利用率为3.1%,翌年8月上旬达17.8%,以5月上旬吸收最快;肥料损失率以冬春最高,达50.7%,落叶休眠期树体内的^(15)N绝大部分贮藏于多年生枝及根系,其浓度则以短枝、细根为高,长枝最低;春季多年生枝中的^(15)N向新生器官迁移最快,至新梢速长期树体内53.3%的^(15)N分布于长枝中;果实速长期枝叶中的^(15)N已向其它器官回流,尤以长枝最快。Three-year-old pear trees growing in field microplots were treated with ^(15)N -labelled urea via soil in autumn. The results were as follows: The ^(15)N was absorbed by tree in annual cycle, 3. 1% of NDFF was recovered in tree in the current year, 17. 8% of NDFF was recovered in the tree in the first ten-day period of August the following year, the ^(15)N was absorbed the fastest in the first ten-day period of May; loss percentage of NDFF was the highest from the winter to the spring and 50. 7% of NDFF was lost. The absorbed ^(15)N was largely stored in the trunk and roots during dormant period, the concentration of NDFF was higher in spurs and the fine roots, it was the lowest in the long shoot; the ^(15)N in the perennial branch was rapidly transferred to the new growth in spring, During shoot rapid-growing period 53. 3% of the total ^(15)N in the whole tree was recovered in the long shoot. During fruit rapid-growing period, the ^(15)N in the new shoot, especially in the long shoot were returned to other organs.
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