无花果果实生理指标及其韧皮部卸载途径研究

发布时间：2018-04-17 13:31

本文选题：无花果 + 韧皮部卸载　；参考：《新疆农业大学》2016年博士论文

【摘要】：为了揭示无花果果实发育过程中同化物韧皮部卸载机制,同时为了研究无花果果实发育过程中ABA和乙烯含量与果实成熟的关系,以(Masui Dauphine)无花果果实为试材,分别在坐果后的15天(小绿果)、30天(大绿果)、65天(始红果)、70天(片红果)、85天(全红果)采摘果实,利用透射电子显微镜结合荧光染料示踪技术研究同化物韧皮部卸载路径的变化,同时对果实发育过程中果实大小及色泽变化及可溶性糖、淀粉含量变化、果实发育过程中呼吸速率和乙烯释放量及ABA含量变化进行了研究。果实纵横径变化表明无花果果实生长发育曲线呈典型的双S型曲线,分为三个时期,第1个快速生长期(时期I)、缓慢生长期(时期II)、第2个快速生长期(时期III),也即果实快速上色和成熟的时期。缓慢生长期和第2个快速生长期之间为果实发育的转折期“始熟期”。在时期I和时期II,无花果果实内的可溶性糖含量很低,进入始熟期后,果实迅速膨大,同时以葡萄糖和果糖为主的可溶性糖含量迅速增加。淀粉含量在始熟期前迅速减少,始熟期后淀粉含量下降趋势趋缓。透射电子显微镜对无花果果实发育过程中韧皮部超微结构观察表明,在始熟期前的时期I和时期II,筛管伴胞复合体和周围薄壁细胞之间存在大量的胞间连丝从而形成共质体联系,但是始熟期后由共质体联系变为共质体隔离,但在薄壁细胞之间始终存在大量的胞间连丝。荧光染料示踪结合激光共聚焦扫描显微镜观察表明,荧光染料在始熟期以前从维管束韧皮部中释放到周围薄壁细胞中,然而在始熟期后,染料被严格限制在韧皮部内部没有卸出到周围薄壁细胞。无花果果实发育过程中ABA含量整体呈下降趋势,乙烯释放量随着果实发育逐渐增加,在始熟期和呼吸速率同步出现一个高峰。以上结果表明无花果果实发育的始熟期是同化物韧皮部卸载由共质体向质外体转变的转折期,同时韧皮部后运输始终为共质体途径。无花果果实是呼吸跃变型果实,乙烯诱导果实发生一系列生理生化变化,促使无花果果实成熟,另外,ABA可能直接参与了始熟期的调控。
[Abstract]:In order to reveal the mechanism of assimilate phloem unloading during the development of fig fruit, and to study the relationship between the content of ABA and ethylene during the development of fig fruit and the fruit maturity, Masui Dauphine fig fruit was used as the material.15 days after setting the fruit (30 days for the small green fruit (65 days for the big green fruit), 70 days for the first red fruit and 85 days for the whole red fruit),The change of unloading path of assimilate phloem was studied by means of transmission electron microscope (TEM) and fluorescent dye tracer technique. Meanwhile, the changes of fruit size and color, soluble sugar and starch content during fruit development were studied.The changes of respiration rate, ethylene release and ABA content during fruit development were studied.The variation of vertical and transverse diameter of the fruit indicates that the growth and development curve of the fig fruit is a typical double S-shaped curve, which is divided into three periods.The first rapid growth period (stage I), the period of slow growth (stage II), the second period of rapid growth (stage II), that is, the period of rapid fruit color and maturation.Between the slow growth period and the second fast growing stage, the transition period of fruit development is "the beginning maturity period".In stage I and stage II, the soluble sugar content in fig fruit was very low, and the content of soluble sugar, which was mainly glucose and fructose, increased rapidly after the beginning of ripening.Starch content decreased rapidly before maturing period, and decreased slowly after maturing period.The ultrastructure of phloem during the development of fig fruit was observed by transmission electron microscope.In the prematurity stage I and II, there was a large number of intercellular ligaments between the sieve tube adjunct complex and the peripheral parenchyma cells to form a symplast connection, but after the initial maturation stage, the symplast connection changed from the syncytic connection to the euplasmic isolation.However, there is always a large number of plasmodesmata between parenchyma cells.Fluorescence dye tracing combined with laser confocal scanning microscopy showed that fluorescent dyes were released from the phloem of vascular bundle into peripheral parenchyma before maturation, but after maturation,The dye is strictly confined to the phloem and does not unload the surrounding parenchyma.During the development of fig fruit, the content of ABA decreased, and the ethylene release increased with the development of the fruit, and a peak appeared at the beginning of ripening and the respiration rate.The above results indicated that the initial maturation stage of fig fruit development was the transition period of the unloading of assimilate phloem from the euplasm to the plastid ectoplast and the transport after phloem was always a hypoplast pathway.Fig fruit is a kind of respiration fruit. Ethylene induces a series of physiological and biochemical changes and promotes the fruit ripening. In addition, ABA may be directly involved in the regulation of early ripening stage.
【学位授予单位】：新疆农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S663.3

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