烟草的不同器官薄层培养形成花芽的研究

FLORAL BUD FORMATION FROM DIFFERENT TOBACCO ORGAN THIN-LAYER CULTURE

烟草不同器官薄层离体培养形成花芽受植株生长发育时期的影响。植株处于营养生长时期,茎表皮薄层无花芽分化能力。随着植株营养生长转向生殖生长,在抽苔、现蕾、开花、结籽不同发育阶段,主茎上不同部位的茎表皮出现花芽的频率不同。植株现蕾时,只有接近顶端第一节的茎薄层出现花芽分化,随植株的发育,逐渐延伸到第四、五节。植株果实成熟时,主茎薄层分化花芽能力又复减弱。花芽分化的趋势却向花序分枝、花柄、果柄延伸,使??它们的薄层组织有分化花芽能力。此外,还观察到花序上小叶也可直接分化花芽。培养基内附加不同配比的植物激素对薄层花芽分化有促进作用。

The growth and development of donorplant was effected on floral bud formation intobacco epidermis thin-layer culture of dif-ferent organ. All parts of the stem epidermis didn't di-fferentiate to floral bud in vegetative stage ofthe donor plant.When plant vegetative stagetransferred to various reproductive stages (iebolting,budding,blooming and setting seeds),the frequency of floral bud emergence wasdifferent in various parts of main stem,dur-ing the stage of floral budding,the floralbuds were only differentiated in apex firstinternode epidermis.Following the variousdevelopment stages of donor plant,the emer-gence of floral bud gradually extended to5—6 internode thin-layer culture.The abi-lity of floral bud differentiation of main stemwas reduced in fruit mature stage,Duringthis time the tendency of floral bud differen-tiation was toward branches of inflorescence,pedicles and fruit stem successively.In addi-tion,the floral bud formation was observeddirectly on the leaflet of inflorescence.(ta-ble 1,2.) The floral bud differentiation of thin-layer culture was promoted by applicationvarious combination of plant growth regula-tors in media.