外源赤霉素处理影响湖北梣种子萌发过程的生理机制  

Physiological mechanisms of exogenous gibberellin treatment affecting the seed germination process of Fraxinus hupehensis Chiú.Shang et Su

作　　者：赵怡宁 刘彦宏 郑鹏丽 周明芹[1] ZHAO Yi-ning;LIU Yan-hong;ZHENG Peng-i;ZHOU Ming-qin(College of Horticulture and Gardening,Yangtze University,Jingzhou 434000,Hubei,China)

机构地区：[1]长江大学园艺园林学院,湖北荆州434000

出　　处：《湖北农业科学》2024年第5期70-76,83,共8页Hubei Agricultural Sciences

基　　金：国家自然科学基金资助项目(31200528)。

摘　　要：以常温贮藏2年的湖北梣(Fraxinus hupehensis Chiú.Shang et Su)种子为研究对象,试验前去除种子胚根端被覆组织以露出胚根。以清水作对照,用150 mg/L赤霉素浸种24 h后,测定种子萌发过程中生理生化指标及内源激素含量的变化。结果表明,赤霉素浸种可以提高种子发芽率,赤霉素处理后种子发芽率为24.67%,对照为16.67%;萌发过程中,赤霉素处理后种子可溶性糖含量呈先上升再下降的变化趋势;可溶性蛋白质含量呈下降趋势,各时期均显著高于对照;超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性整体呈上升趋势;赤霉素处理后的种子内源茉莉酸甲酯(JA-Me)含量均显著低于对照,更有利于内源赤霉素(GA_(3))、玉米素核苷(ZR)含量的增加;生长素比脱落酸(IAA/ABA)与赤霉素比脱落酸(GA_(3)/ABA)和玉米素核苷比脱落酸(ZR/ABA)分别在0.01和0.001水平上呈显著正相关;GA_(3)/ABA与ZR/ABA在0.001水平上呈显著正相关。赤霉素浸种显著提高了湖北梣种子的发芽率,处理后的种子平衡保护酶活性系统较强,质膜受损延缓,抗逆能力较好。较低内源JA-Me含量和较高内源GA_(3)、ZR有利于种子萌发的启动和休眠的解除。The seeds of Fraxinus hupehensis stored at normal temperature for 2 years were taken as the research object.Before the ex-periment,the radicle end covering tissue was removed to expose the radicle.Taking water as a control,after soaking the seeds with 150 mg/L gibberellin solution for 24 h,the physiological and biochemical indexes and the contents of endogenous hormones in seeds during germination were measured.The results showed that gibberellin treatment could enhance seed germination rate,with a germina-tion rate of 24.67%after gibberellin treatment compared to 16.67%in the control group.During germination,gibberellin-treated seeds exhibited a trend of initially increasing and then decreasing in soluble sugar content.Soluble protein content showed a decreasing trend but remained significantly higher than the control group at all stages.Superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)activities showed an increasing trend on the whole.The content of endogenous jasmonic acid methyl ester(JA-Me)in seeds af-ter gibberellin treatment was significantly lower than that in the control,which favored an increase in endogenous gibberellin(GA_(3))and zeatin riboside(ZR)content.The ratios of gibberellin to abscisic acid(GA_(3)/ABA)and zeatin riboside to abscisic acid(ZR/ABA)were significantly positively correlated with the ratio of indole-3-acetic acid to abscisic acid(IAA/ABA)at 0.01 and 0.001 levels,re-spectively,and GA_(3)/ABA was significantly positively correlated with ZR/ABA at 0.001 level.Gibberellin immersion significantly in-creased the germination rate of Fraxinus hupehensis seeds,and the seeds treated with gibberellin exhibited a stronger balance of protec-tive enzyme activity system,delayed membrane damage,and the resistance was better.The lower levels of endogenous JA-Me and the higher levels of endogenous GA_(3) and ZR favored the initiation of seed germination and the release of dormancy.

关 键 词：湖北梣(Fraxinus hupehensis Chiú.Shang et Su) 种子 生理生化 萌发 赤霉素 

分 类 号：S792.41[农业科学—林木遗传育种]