冬枣果实发育期不同类型枝条叶施15N-尿素的分配特性

大田条件下,以6年生冬枣/金丝小枣为试材,研究了冬枣果实发育后期不同类型枝条叶施15N-尿素7 d后15N的吸收与分配特性.结果表明:处理叶片中的Ndff%均高于其他器官,且果实膨大期处理叶片高于果实硬核期.不同类型枝条对叶施15N-尿素的分配运转特性不同,坐果枣吊叶片主要供给果实生长;顶部营养枝叶片吸收15N在其附近器官中的分配势较高;中部营养枝叶片的下部器官15N分配势高于其上部相同的器官,果实膨大期顶部营养枝叶片处理15N最远可运输到根系.不同施15N时期营养枝叶片对15N分配利用不同,果实硬核期吸收15N在营养器官(叶片和枣吊)中的分配势较高,而果实膨大期15N在贮藏器官(枝干)中的分配势较高.

Characteristics of Distribution of Different Types of Shoots Foliar 15N-urea Sprays During Fruit Development Period in Winter Jujube Trees

A field experiment on 6-year-old Jujube trees was carried out to study assimilation and distribution of nitrogen from urea applied to different type of shoots during fruit development period.The results showed that higher Ndff% was detected in the treated leaves than in other organs 7 d after application,and Ndff% in leaves treated during fruit rapid-swell stage was higher than that treated during fruit core-hardening stage.Bearing deciduous spur foliar spray contributed most to fruit N.Neonatal branch leaves applied ~(15) N-urea,however,was detected with higher Ndff% in organs to which the treated leaves were attached.Urea-N could exported to below organs.~(15)N could be detected in fine roots after top neonatal branches leaves treated during fruit rapid-swell stage.The distribution of ~(15) N-urea of neonatal branches foliar was affected by fertilization time.~(15)N applied during core-hardening stage of fruit exported more to vegetative organs(leaves and deciduous spur),but during rapid-swell stage more ~(15) N was distributed to storage organs(branches).