摘要
以浙江省遂昌县东京野茉莉新鲜种子为材料,通过对种子透水性、种被机械阻力、离体胚培养、发芽抑制物质提取及种子层积过程中的生理生化变化的研究,并利用赤霉素(GA3)进行发芽前预处理,探讨种子休眠机理及破除方法。结果表明:1)离体胚并无休眠特性,胚外组织中也不存在发芽抑制物质。尽管种子透水性影响其发芽率,但胚乳和种壳的机械束缚是东京野茉莉种子休眠的主要原因之一。2)层积后再机械处理可解除种子休眠。休眠能被赤霉素和(或)低温层积处理解除,说明种子同时存在生理抑制,其休眠类型属于综合性休眠。3)贮藏物质在层积过程中的动员与种子萌发率的提高密切相关,种内可溶性糖含量(R=0.885)、POD活性(R=0.658)与休眠的解除呈显著正相关。4)层积30 d后1 200 mg/L GA3处理的种子发芽率最高,为54%。胚的外覆物控制东京野茉莉的种子休眠,休眠解除的过程伴随种子内代谢水平的提高。
The fresh Styrax tonkinensis seeds were collected from Suichang county,Zhejiang province.Through the investigations on the physiological and biochemical changes in seed permeability,seed coat mechanical resistance,in vitro embryo culture,extraction of inhibitors of germination and seed stratification,and pretreatment with gibberellin(GA)before germination,the mechanism and release methods of seed dormancy were discussed.The results show that1)the isolated embryos of the mature seeds had no characteristic of dormancy,and the leaching solution of the seed shell and endosperm did not contain germination inhibitors.The main reason causing seed dormancy was the mechanical obstacle of the seed shell and endosperm,while the permeability of the seed coat,which was not the main reason causing seed dormancy,also had some influences to seed germination;2)Mechanical treatment after stratification can relieve seed dormancy.The dormancy could be released by gibberellin and(or)cold stratification,which suggested that there was the physiological dormancy in S.tonkinensis seeds,and the dormancy type was a comprehensive one;3)the seed reserve mobilization tied closely to the dormancy release during cold stratification.In the process of breaking seed dormancy,the soluble sugar contents and POD activities showed an increasing trend along with the increasing of seed percentage germination,and the correlation coefficient was0.885and0.658respectively,which of both reached the significant level(P<0.01);4)The seed germination rate of1200mg/L GA treated GAP after30days of stratification was the highest,which was54%.The findings suggest that covering structure outside the S.tonkinenesis embryo controlled the seed dormancy,and the dormancy release was related to the up-regulation level of seed metabolism.
作者
赵婕
张子晗
侯秋彦
喻方圆
ZHAO Jie;ZHANG Zihan;HOU Qiuyan;YU Fangyuan(College of Forestry,Nanjing Forestry University,Nanjing 210037, Jiangsu, China;Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University,Nanjing 210037, Jiangsu, China;Nanjing Innovation Education Information Consulting Co., Ltd, Nanjing 210028, Jiangsu, China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2019年第1期45-51,共7页
Journal of Central South University of Forestry & Technology
基金
江苏省林业三新工程项目"六合野茉莉苗木高效培育技术示范与推广"(lysx[2014]26)
江苏高校优势学科建设工程项目
关键词
东京野茉莉
种子休眠
休眠解除
低温层积
赤霉素
Styrax tonkinensis
seed dormancy
dormancy release
cold stratification
gibberellin
