杧果短截结果母枝玉米素核苷含量的动态变化

Dynamic changes in zeatin nucleoside (ZR) content of mango cutback fruit branch

【目的】测定杧果花芽分化期间结果母枝各器官内玉米素核苷(ZR)含量,探索ZR在杧果花芽分化中的作用。【方法】利用杧果花枝短截后剪口芽在当年还能再次花芽分化并开花结果的现象,应用酶联免疫吸附分析方法(ELISA)定期测定剪口叶、附近韧皮部及芽内ZR含量。【结果】短截结果母枝后,剪口叶、附近韧皮部和剪口芽内ZR含量分别于2月25、20日和3月2日降至最低,为1.73、1.52、2.0μg·g-1FW;叶片、韧皮部及剪口芽于3月12日达最大值,为6.39、8.47、10.32μg·g-1FW。2月25日剪口芽芽眼中心颜色逐渐呈蜡黄,并向芽体四周扩散;3月2～7日,芽体逐渐膨大,蜡黄色加深,芽眼呈半透明状;3月7日后绿色逐渐增加,半透明状消失。【结论】ZR在杧果花芽分化的不同阶段具有不同作用。花芽分化临界期前,ZR含量低,生长点细胞活性下降,有利于杧果植株从叶芽生理状态转化为花芽生理状态;花芽临界期后,相对高的ZR含量有利于杧果植株生长点进行花芽分化。

【Objective】The zeatin nucleoside （ZR） content in various organs of mango fruiting branches during the flower bud differentiation period was determined in order to explore the role of ZR in mango flower bud differentiation. 【Method】Utilizing the phenomenon of re-blossoming and re-fruiting in mango pruning buds after cutting back the fruit branches, the enzyme-linked immunosorbent assay method （ELISA） was applied to determine the ZR contents in pruning leaf, phloem, and buds. 【Result】After pruning the fruiting branches, the ZR contents of pruning leaf, phloem, and pruning buds reached minimum at 1.73, 1.52, and 2.0μg·g^-1 FW on February 25, February 20, and March 2, respectively. The ZR contents of pruning leaf, phloem, and buds reached maximum at 6.39, 8.47, and 10.32 μg·g^-1FW respectively on March 12. On February 25, the color of the central heart area in pruning buds gradually turned sallow and proliferated around the shoot area. From March 2 to March 7, the buds gradually dilated, sallow color deepened, and the central heart area appeared translucent. After March 7, green color expanded and the translucent appearance disappeared. 【Conclusion】The ZR exhibited different roles at different stages of mango fruit flower bud differentiation. During the critical period of flower bud differentiation, the ZR content was low and the cell activity growth decreased, which were beneficial qualities for mango plants to transform from the bud physiological state into the flower bud physiological state. After the critical period of flower bud differentiation, relatively high ZR content was advantageous for the flower bud differentiation process in mango plant growth.