银杏雌、雄植株花芽分化后期及开花期间生理代谢的比较

【目的】研究银杏雌、雄株花芽分化后期及开花期间内含物和激素代谢的动态变化,为银杏雌、雄株的定向培育、授粉、性别鉴定提供参考。【方法】通过采集银杏雌、雄株花芽分化后期(11月25日—次年3月16日)、开花期(3月17日—4月7日)、开花后(4月8日—4月28日)3个阶段短枝果芽及开花后的叶片,测定其可溶性糖、可溶性蛋白、黄酮和内酯等内含物及激素含量。【结果】在花芽分化后期,银杏雄株普遍比雌株含有更多的可溶性糖和可溶性蛋白,其苯丙氨酸解氨酶(PAL)活性也更高;而在开花期,银杏雌株比雄株含有更多的可溶性糖、淀粉和可溶性蛋白,其PAL活性也更高,但此期间雄株的赤霉素(GA)和玉米素(ZT)含量远高于雌株。雌、雄植株芽期的过氧化物酶(POD)活性远高于开花期和花后期,而开花期间雌、雄株叶片都具有较高的ZT、GA、总黄酮和萜内酯水平。【结论】银杏雌、雄株在开花时间各节点的生理代谢水平出现不同步性,雄株的可溶性糖、可溶性蛋白、总黄酮和萜内酯的高点比雌株早2周左右。较高水平的GA和ZT、总黄酮和萜内酯可能是银杏雄株开花及雌株胚珠发育所必需的。

Comparisons of physiological metabolism of female and male Ginkgo biloba trees during the late flower bud differentiation and flowering

【Objective】 The study aimed to investigate the dynamic changes in hormones and physiological metabolism indicators such as carbohydrates and flavonoids to provide a reference for the directional cultivation, pollination and gender identification of male and female Ginkgo biloba trees. 【Method】 Short fruit buds and leaves were collected from ginkgo trees during three developmental phases, that is, late flower bud differentiation (November 25 of previous year to March 16 of next year), flowering (March 17 to April 7), and after flowering (April 8 to April 28) to analyze the changes in the levels of hormones, carbohydrates, soluble proteins, total flavonoids, lactones, and peroxidase (POD) as well as phenylalanine ammonia-lyase (PAL) enzyme activities in female and male ginkgo trees. 【Result】 During the late flower bud differentiation stage, male trees had higher soluble sugar and protein contents and PAL activity than female trees, whereas during the flowering period, female trees had comparatively higher concentrations of soluble sugar, starch, soluble protein and PAL activity. However, gibberellin (GA) and zeatin (ZT) levels were significantly higher in the male trees during the flowering period. The considerably higher POD activity was observed in the female and male trees during the late flower bud differentiation period than during the other two periods, while the higher levels of ZT, GA, flavonoids and terpene lactones were observed during the flowering period. 【Conclusion】 Male and female ginkgo trees exhibited unsynchronized physiological metabolisms at the flowering time, and the peaks of soluble sugar, soluble protein, flavonoid and terpenoid lactone levels in male trees were observed approximately two weeks earlier than those in the female trees. High levels of GA, ZT, flavonoids and terpene lactones may be necessary for flowering and ovule development in male and female ginkgo trees, respectively.