5种石斛花器官特性及人工授粉研究

Studies on Hand Pollination of Five Dendrobium Species and Their Organ Morphology

对石斛属翅萼石斛(D.cariniferum Rchb.f.)、棒节石斛(D.findlayanum Par.et Rchb.f.)、玫瑰石斛(D.crepidatum Lindl.ex Paxt.)、晶帽石斛(D.crystallinum Rchb.f.)、黄花石斛(D.dixanthum Rchb.f.)5个种的花器官形态和人工授粉技术进行研究。结果表明,不同种石斛花期不一致,花期长的盛花期长,花期短的盛花期短;同一种石斛受温度影响开花时间不一样。参试石斛合蕊柱长、宽和粘液厚度全部大于花粉粒,同一种石斛合蕊柱能够容纳下本种的花粉粒,粘液覆盖花粉粒。翅萼石斛开花第5~10 d授粉效果最好,棒节石斛、玫瑰石斛、晶帽石斛和黄花石斛开花第1~4 d授粉效果好;翅萼石斛和棒节石斛异株异花授粉效果最好,玫瑰石斛、晶帽石斛和黄花石斛三种授粉方式坐果差异不明显。花期对石斛坐果率的影响较大,花期长的授粉期限长,花期短的授粉期限短,石斛人工授粉最好在盛花期进行。

Experiment of five species of Dendrobium spp.was conducted to study their organ morphology and hand-pollination.The results indicated that the flowering period differs in species of Dendrobium.The longer the flowering lasts,more days the full blossom would have,the short flowering period usually comes up with short blooming time.The flowering time of the same species also differs as influenced by temperature.The length and width of gynostemium and mucus thickness are bigger than the volume of pollen grains in all tested Dendrobium.Therefore,the pollen grains of the same species could be wholly contained in stigma and covered by their own mucus.Of whichD.cariniferum Rchb.f.has the best effect of pollination after flowering in 5 to 10 days while the other four species(D.findlayanum Par.et Rchb.f.,D.crepidatum Lindl.ex Paxt.,D.crystallinum Rchb.f.and D.dixanthum Rchb.f.,respectively)showed best after flowering in 1 to 4 days.Furthermore,it is found that cross pollination with different strains is the best way to species of D.cariniferum Rchb.f.and D.findlayanum Par.et Rchb.f.,so does the hand pollination.There is no obvious difference in fruit setting under three pollination treatments to species of D.crepidatum Lindl.ex Paxt.,D.crystallinum Rchb.f.and D.dixanhum Rchb.f.The flowering period has great influence on fruit setting of Dendrobium,pollination period would depend on the flowering period.It`s suggested that hand pollination should be done in the full blossom period.