多中心干树形对苹果碳氮营养分配和利用的影响

Effects of multi-center stem canopy shape on carbon and nitrogen nutrient allocation and utilization in apple

以3年生维纳斯黄金/M9苹果树为试材,利用同位素^(13)C和^(15)N示踪技术,研究了多中心干形树形与自由纺锤形对苹果^(13)C和^(15)N吸收、分配与利用的影响。结果表明,多中心干形和自由纺锤形的Ndff值均表现为果实>根系>叶片>枝条>主干,^(15)N分配率均表现为叶片>枝条>根系>果实>主干,^(13)C分配率均表现为叶片>枝条>主干>果实>根系。但各器官在数值间存在差异,自由纺锤形树体结构大,根系发达,各器官Ndff值与^(15)N吸收量均比多中心干形高,^(15)N利用率提高,枝条^(15)N分配率提高;多中心干形果实^(15)N分配率提高,根系和果实的^(13)C分配率也均提高,平均单果重比自由纺锤形提高,可滴定酸含量降低。综上,维纳斯黄金/M9采用多中心干形具有削弱树势、提高果实^(15)N和^(13)C分配率、提升果实品质的效果。

A three-year-old Venus Gold/M9 apple tree was used as a sample to study the effects of multi-center stem canopy shape (Guyot) and free spindle shape on the absorption,allocation and utilization of^(13)C and^(15)N by isotope^(13)C and^(15)N tracer techniques.The results showed that the Ndff values of multi-center stem canopy shape and free spindle shape were in the order of fruit>root>leaf>branch>trunk,the distribution rate of^(15)N was in the order of leaf>branch>root>fruit>trunk,and the distribution rate of^(13)C was in the order of leaf>branch>trunk>fruit>root.However,there were differences in the values of each organ.The free spindle tree had large structure and developed root system,and the Ndff value and^(15)N absorption amount of each organ were higher than that of the multi-center stem canopy,and the utilization rate of^(15)N and the allocation rate of branches were increased.The distribution rate of^(15)N in multi-center stem canopy fruits was increased,the distribution rate of^(13)C in roots and fruits was also increased,the average fruit weight ratio of free spindle was increased,and the titratable acid content was decreased.In conclusion,the Venus Gold/M9 multi-center stem canopy shape has the effects of weakening tree potential,improving the^(15)N and^(13)C distribution rate of fruit,and improving fruit quality.