鹅掌楸属植物花粉萌发前后壁的超微结构

观察描述了在电镜下中国鹅掌楸（Ｌｉｒｉｏｄｅｎｄｒｏｎｃｈｉｎｅｎｓｅ）和北美鹅掌楸（Ｌ．ｔｕｌｉｐｉｆｅｒａ）２种植物花粉壁的超微结构及其水合后的变化。（１）成熟花粉壁由６层组成，即外壁３层──外层，中层１和中层２，内壁３层──内壁１，内壁２和内壁３。（２）花粉水合时，在内壁３与质膜之间由Ｐ一粒子（多糖－粒子）和被膜小泡参与形成新层。（３）花粉萌发时，由内壁３的一部分和新层突出萌发孔共同形成花粉管壁。（４）新层于花粉管形成早期分成２层──外染色深的果胶层和内电子透明的胼胝质层。

ULTRASTKUCTURE OF POLLEN WALL DURING GERMINATION IN LIRIODENDRON

The ultrastructure and changes after hydration of pollen wall in Liriodendron chinense and L. tulipifera were observated by electron microscope. The results were shown follows:(1)The mature pollen wall consists of six layers which are exine sexine,nexine 1,nexine 2,intine 1,intine 2 and intine 3.(2) During hydration of pollen,new layer(pollen tube preparing layer)is formed be- tween intine 3 and vegetative cell plasma membrane by P particles and coated vesicle(3)When pollen germinates,pollen tube wall forms by protruding of part of intine 3 and new laver from germinating aperture.(4)Early stage ofpollen tube differentiates into two layerspection outer lay- er which is dark and callose inner layer which is electron transparent.