长花柱型滇丁香小孢子发生及雄配子体发育

利用常规石蜡切片法和细胞学压片法,对异型花柱植物滇丁香的长花柱型植株的小孢子发生、雄配子体发育及花粉萌发进行观察。结果表明:(1)长花柱型滇丁香具5枚花药,花药4室。(2)花药壁由1层表皮、1层花药内壁、2层中层和1~3层绒毡层组成;花药壁发育方式为基本型,绒毡层类型为腺质绒毡层。(3)小孢子母细胞减数分裂的胞质分裂为同时型,四分体排列方式为四面体型,偶有左右对称型;不同药室间小孢子母细胞减数分裂不同步。(4)成熟花粉粒为二细胞型。(5)小孢子发生和雄配子体发育过程正常,表明长花柱型滇丁香属于发育正常的两性花。(6)授粉4h后,长花柱型滇丁香的花粉在长、短两种花柱柱头上的萌发率分别达(91.8±1.6)%和(93.2±1.1)%,且两者间无显著性差异(t=1.585,df=8,p=0.152),表明长花柱型滇丁香的成熟花粉粒在长、短两种花柱柱头上的萌发均正常。

Microsporogenesis and Male Gametophyte Development of Long-style Flower of Luculia pinciana(Rubiaceae)

The formation of microspore,development of male gametophyte and germination rate of pollen grains in long-style flower of Luculia pinciana(Rubiaceae) were observed by traditional paraffin section technique and cytology compression method.The results showed:(1)Long-style flower of L.pinciana had five anthers,and the anther was tetralocular.(2)The anther wall was composed of one epidermis,one endothecium,two middle layers and one to three tapetums from outer to inner.The development type of anther wall was of basic type and the tapetum belonged to glandular type.(3)During meiosis of the microspore mother cells,cytokinesis was simultaneous type,and the tetrads were mostly tetrahedral,occasionally found isobilateral.Meiosis of microsporocyte was asynchronous between different anther chambers.(4)Mature pollen grains were two-cell type at dispersal stage.(5)Microsporogenesis and male gametophyte development of long-style flower of L.pinciana showed normally,and was of bisexual flower.(6)The artificial germination rate of pollen grains between on the stigma of long-styled and short-styled flowers was (91.8±1.6)% and (93.2±1.1)% respectively,and did not differ significantly(t=1.585,df=8,p=0.152).It was suggested that pollen grains of long-style flower germinated normally between on the two stigmas.