甜樱桃对15N尿素的吸收、分配和利用特性

以5年生‘早大果’甜樱桃为试材, 研究了其在萌芽前土施¹⁵N尿素的吸收、分配和利用特性.结果表明：植株器官从肥料中吸收分配到的¹⁵N量对该器官全氮量的贡献率(Ndff)均随时间推移逐渐升高, 盛花期细根和贮藏器官的Ndff较高; 果实硬核期，新生器官中长梢和长梢叶的Ndff增长迅速，分别达0.72%和0.59%; 果实硬核期到采收期，果实的Ndff增长迅速，到采收期达到最高，为1.78%; 果实采收后到花芽分化期，新生器官Ndff增长减慢而贮藏器官增长迅速.盛花期根系吸收的氮素首先分配到贮藏器官，粗根¹⁵N分配率最高，为54.91%；果实硬核期细根和贮藏器官¹⁵N分配率由盛花期的85.43%下降到55.11%，而地上部新生器官则升高至44.89%；果实采收期¹⁵N分配率变化不大，果实采收后氮素营养迅速向贮藏器官中运转，花芽分化期细根和贮藏器官的¹⁵N分配率升高至72.26%，而地上部新生器官¹⁵N分配率与采收期相比下降了19.31%.从盛花期到花芽分化期，植株对¹⁵N尿素的当季利用率呈升高趋势，于花芽分化期达到最高，为16.86%.

Characteristics of urea 15N absorption, allocation, and utilization by sweet-cherry (Prunus avium L.).

With five-year old 'Zaodaguo' sweet-cherry (Prunus avium L.) as test material, this paper studied the characteristics of its urea 15N absorption, allocation, and utilization when applied before bud-break. The results showed that the Ndff of different organs increased gradually with time, and was higher in fine roots and storage organs at full-blooming stage. At fruit core-hardening stage, the Ndff of long shoots and leaves increased quickly, reaching to 0.72% and 0.59% , respectively. From fruit core-hardening to harvesting stage, the Ndff of fruit had a rapid increase, with the peak (1.78%) at harvesting stage. After harvest, the Ndff of neonatal organs increased slowly while that of storage organs increased quickly. At full-blooming stage, the absorbed 15N in roots was firstly allocated to storage organs, with the highest allocation rate (54.91%) in large roots. At fruit core-hardening stage, the allocation rate in fine roots and storage organs decreased from 85.43% to 55.11%, while that in neonatal branches and leaves increased to 44.89%. At harvesting stage, the allocation rate in different organs had no significant change, but after harvest, the absorbed 15N had a rapid translocation to storage organs, and the allocation rate in fine roots and storage organs reached the highest (72.26%) at flower bud differentiation stage. The 15N allocation rate in neonatal branches and leaves at flower bud differentiation stage was decreased by 19.31%, compared with that at harvesting stage. From full-blooming to flower bud differentiation stage, the utilization rate of urea 15N was increasing, and reached the peak (16.86%) at flower bud differentiation stage.