摘要
本文以成熟的青杄花粉为试验材料,用不同浓度钙拮抗剂EGTA和抑制剂AlCl_3进行处理,观察花粉的萌发和花粉管的生长情况,同时用选择性电极测定了不同发育时间内花粉管顶端钙离子流,以及EGTA和AlCl_3对钙离子流的影响,以探讨钙对青杄花粉生长发育的调控机制。结果发现:(1) 0.5 mmol·L^(-1) EGTA处理花粉后,会促进花粉萌发,萌发率升高;但花粉管长度低于对照组;1 mmol·L^(-1) EGTA处理后,花粉萌发率和花粉管长度都低于对照组;0.1 mmol·L^(-1)和0.5 mmol·L^(-1) AlCl_3处理后,花粉萌发率和花粉管长度都会显著降低;(2)通过非损伤微测技术发现,对照花粉在水合时期(培养3,6,9 h)钙离子外流,在萌发及快速伸长期钙离子内流(培养12,15,18 h);EGTA和AlCl_3培养花粉后,花粉的水合期、萌发期和花粉管的伸长期的钙流状况会出现异常,其中包括钙流的内流和外流的状况以及流速,从而导致各个时期花粉的萌发率及和花粉管长度的改变,导致花粉管的生长异常。(3)对照花粉管顶端出现Ca^(2+)浓度梯度,而0.5 mmol·L^(-1) EGTA处理的花粉会相比对照组提前在花粉管顶端出现Ca^(2+)浓度梯度,以促进花粉萌发;1 mmol·L^(-1 )EGTA,0.1 mmol·L^(-1) AlCl_3和0.5 mmol·L^(-1) AlCl_3处理后Ca^(2+)浓度梯度消失。由此表明花粉的不同生长时期对钙离子的需求不同,且钙离子对花粉管的萌发及生长起着至关重要的作用。
In the present study,mature Picea wilsonii Mast pollen was chosen to study the regulatory mechanism of Ca^2+on pollen growth and development.EGTA and AlCl3 with different concentrations were added to the media at the beginning.Meanwhile,dynamics of calcium influx and efflux were studied by microelectrodes and[Ca^2+]c was observed with lasing confocal scanning microscopy.The results show that:(1)0.5 mmol·L^-1 EGTA stimulates pollen germination,but inhibits pollen tube elongation.1 mmol·L^-1 EGTA and AlCl3 inhibit pollen germination.(2)Calcium fluxes are observed during pollen hydration,germination and tube growth,and EGTA and AlCl3 affect calcium fluxes.(3)[Ca^2+]gradient exists in control pollen tubes.However,EGTA and AlCl3 with different concentrations have different effects on the gradient.In a word,pollen has different requirements for calcium ions during different developmental stages,and calcium plays a crucial role during pollen hydration,germination and tube growth.
作者
杜兵帅
胡海文
曹庆芹
秦岭
房克凤
DU Bing-shuai;HU Hai-wen;CAO Qing-qin;QIN Ling;FANG Ke-feng(College of Landscape Architecture,Beijing University of Agriculture,Beijing 102206;Beijing Key Laboratory for Agricultural Application and New Technique/College of Plant Science and Technology,Beijing University of Agriculture,Beijing 102206;Beijing Collaborative Innovation Center for Eco-Environmental Improvement with Forest and Fruit Trees,Beijing 102206;Liucun Township People’s Government of Changping District of Beijing Municipality,Beijing 102204,China)
出处
《电子显微学报》
CAS
CSCD
北大核心
2018年第6期627-636,共10页
Journal of Chinese Electron Microscopy Society
基金
国家自然科学基金资助项目(No.31270719)
科技创新服务能力建设-协同创新中心-林果业生态环境功能提升协同创新中心(No.CEFF-PXM2017_014207_000024)
北京市属高等学校创新团队建设与教师职业发展计划项目(No.IDHT20180509)
