草烏頭種子層積過程中內(nèi)源激素變化和相關基因表達分析

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Abstract：This study aimed to elucidate the regulatory mechanisms underlying seed dormancy release in Aconitum kusnezofii Reichb.by monitoring embryo-to-endosperm length ratio （embryo rate）and quantifying endogenous hormone levels and expression of related genes at key stratification stages.The embryo rate exhibited a “slow-rapid-slow” pattern： remaining stable at 23.31% from day O to 14，sharply increasing to 90.91% by day 42，followed by radicle elongation （0.75cm at day 49） and cotyledon emergence at day 54. Hormone analysis showed a significant decline in abscisic acid （ABA） content（46. 48% reduction compared to day O），while gibberellin A3 （ GA3′ ），indole-3-acetic acid（IAA），methyl jasmonate（MeJA），and brassinosteroid（BR） increased by 34. 77% ， 60.71% ， 97.53% ，and 17.95% ，respectively. Zeatin riboside（ZR） content rose initially，and then declined.Ratios such as GA3/ABA and IAA/ABA significantly increased，indicating enhanced antagonism from growth-promoting hormones against ABA during dormancy release. Expresion analysis showed that key genes involved in hormone metabolism CYP7O7A2（ABA degradation）， KAO （GA biosyn thesis），and YUCCA（IAA biosynthesis） were significantly upregulated，consistent with hormonal changes. Collctively，the continuous decline in ABA content may serve as a key driver of dormancy release，while increased GA3 ， IAA，MeJA，and BR levels may synergistically and antagonistically interact with ABA signaling to promote embryo development and seed germination.

Key words：Aconitum kusenezofii Reichb. ;Seed dormancy;Embryo-to-endosperm ratio;Hormone

草烏頭（AconitumkusnezoffiiReichb.）為毛茛科多年生草本，廣泛分布于我國東北、華北地區(qū)。（剩余10307字）