离体梨花柱S-RNase对自体花粉管超微结构变化的影响  

Effect of Pear Stylar S-RNase on Self-pollen Tube Ultrastructure in Vitro

作　　者：刘珠琴[1] 张绍铃[1] 徐国华[2] 

机构地区：[1]南京农业大学园艺学院,南京210095 [2]江苏教育学院生物系,南京210013

出　　处：《园艺学报》2007年第4期841-846,共6页Acta Horticulturae Sinica

基　　金：高校博士学科点专项科研基金资助项目(B200523);江苏省博士后科研资助计划项目(0501004B)

摘　　要：采用透射电子显微镜研究了离体条件下‘今村秋’、‘丰水’梨花柱S-RNase对‘今村秋’花粉管生长过程中花粉管超微结构的影响。‘丰水’花柱S-RNase处理的‘今村秋’花粉管(异体,亲和)和对照花粉管结构在生长过程中表现正常,即花粉管顶端生长区域充满细胞质和细胞器,结构完整,花粉管壁上没有胼胝质层分布。而‘今村秋’花柱S-RNase处理的‘今村秋’花粉管(自体,不亲和)超微结构随时间的延长出现衰退现象。处理3h时,自体花粉管内充满细胞质和细胞器,结构完整,但在花粉管的极顶端分泌小泡融合,并且此区域的细胞壁比后部的薄;处理8h后,细胞器出现一定程度的衰退现象,线粒体膨大,嵴减少或消失,内质网膨大并包围在液泡和其它细胞器周围,液泡融合并侵蚀周围的细胞质和细胞器;到24h时,自体花粉管内线粒体、内质网等细胞器消失,只有靠近花粉管前端有少量细胞质存在,细胞壁增厚,并且有一层厚厚的胼胝质层紧靠细胞壁。结果表明,花柱S-RNase能引起自体花粉管的衰退,从而抑制自体花粉管生长。The effects of pear stylar S-RNase on compatible and incompatible pollen tube ultrastructure in vitro were studied with transmission electron microscope. Ultrastructure of compatible pollen tube and control was natural during growth, i.e. cytoplasm and organelles filled tube growth tip and their configurations were intact. There was no callose along the cell wall. While ultrastructure of incompatible tube degenerated gradually followed by treatment time. After treated for 3 h incompatible tube was full of cytoplasm and organelles. There was no callose along the cell wall. But secreting vacuoles fused at the apex of tube and the cell wall was thinner than that of others. Eight hours after treatment mitochondria appeared swelling, cristae de- creased or disappeared, ER dilated and wrapped around vacuoles and other organelles, vacuoles fused and swallowed cytoplasm and organelles. After 24 h, mitochondria and ER disappeared, only a little of cytoplasm laid near the tube tip and the shank nearly were empty. Cell walls became thicker and a layer of callose laid along the cell walls. The result hits pear stylar S-RNase could cause degeneration of incompatible pollen tube and inhibited incompatible tube growth.

关 键 词：梨 自交不亲和性 S-RNASE 花粉管 超微结构 

分 类 号：S661.2[农业科学—果树学]