紫花含笑花发育过程中生理和内源激素的变化

Studies on the Physiological Indexes and Endogenous Hormones Variation During Flower Development in Michelia crassipes

以紫花含笑(Michelia crassipes)绿蕾期、紫蕾期、初开期花芽为试验材料进行生理生化指标测定,并利用UPLC–ESI–MS/MS测定内源激素动态变化。结果表明:可溶性糖、可溶性蛋白、叶绿素含量以及POD活性均随着花芽发育而下降;游离脯氨酸、丙二醛、花青素含量和SOD活性均在紫蕾期最高。整个发育过程中测得8类共49种激素物质,其中绿蕾期花芽内源激素以生长素、水杨酸和脱落酸为主,紫蕾期以生长素为主,初开期则以生长素和茉莉酸为主;赤霉素和乙烯类含量随着花发育呈上升趋势,细胞分裂素和独脚金内酯含量则呈下降趋势;富集分析表明不同发育期差异激素主要富集在次生代谢物合成途径。紫花含笑花发育过程涉及花器官发育和花青素积累,可溶性糖、可溶性蛋白、生长素、脱落酸和茉莉酸可能是推动花发育进程的重要因素。

To study the physiological changes and endogenous hormones variation during the flower development of Michelia crassipes,the flower buds from green flower bud stage,purple flower bud stage and the first-open stage were collected,to measure the physiological indexes and the variant endogenous hormones.The results showed that the contents of soluble sugar,soluble protein,chlorophyll and POD activity were decreased during the development of flower bud.The contents of free proline,malondialdehyde,anthocyanin and SOD activity showed the highest value in purple bud stage.According to the UPLC–ESI–MS/MS analysis,a total of 49 hormone substances belonging to 8 classes were detected during the whole developmental process.The flower buds in green flower bud stage accumulated relatively more auxin,salicylic acid(SA)and abscisic acid(ABA),while in purple flower bud stage,the auxin content accounted for the largest proportion of total hormones.The auxin and jasmonic acid(JA)were the predominant hormones in the first-open stage.Additionally,the gibberellin(GA)and ethylene(ETH)contents were increased during the flower development,but the cytokinin(CK)and strigolactones(SLs)contents were decreased.The hormones with significant difference in the content were screened and significantly enriched in the biosynthesis of secondary metabolites pathway.These results indicated that the different physiological activities and hormone interaction patterns worked cooperatively to regulate the flower organs development and anthocyanin accumulation during flower developmental process.Especially,the soluble sugar,soluble protein,auxin,abscisic acid and jasmonic acid might play an important role.