文心兰花粉离体萌发培养基的筛选及萌发率的测定

Optimized Medium and Culture Conditions for Germination of Oncidium Pollens

【目的】研究不同培养基组分、培养温度及培养时间对文心兰花粉离体萌发的影响,以期筛选出文心兰花粉离体萌发的适宜培养基及培养条件,为文心兰种质资源创新利用提供科学依据。【方法】以盛花期当天开放的花朵为试验材料,采用液体培养基,比较蔗糖、H_(3)BO_(3)、Ca(NO_(3))·4H_(2)O、MgSO_(4)·7H_(2)O及KNO_(3)对文心兰花粉离体萌发的影响,正交试验筛选文心兰花粉离体萌发培养基的最佳组合及培养条件;在此基础上,测定收集保存的68份文心兰种质资源的花粉离体萌发率。【结果】一定质量浓度的蔗糖、H_(3)BO_(3)、Ca(NO_(3))·4H_(2)O、MgSO_(4)·7H_(2)O及KNO_(3)对文心兰花粉的离体萌发具有一定的促进作用,各因素的最佳作用效果从高到低依次为H_(3)BO_(3)、Ca(NO_(3))·4H_(2)O、蔗糖、MgSO_(4)·7H_(2)O及KNO_(3)。正交试验表明适宜的液体培养基组合为100 g·L^(-1)蔗糖+10 mg·L^(-1)H_(3)BO_(3)+50 mg·L^(-1)Ca(NO_(3))·4H_(2)O+20 mg·L^(-1)MgSO_(4)·7H_(2)O+30 mg·L^(-1)KNO_(3),各成分的质量浓度与单因素试验的结果一致;培养条件为25℃、黑暗培养48 h。文心兰花粉离体萌发测定结果表明,60.29%的种质资源的花粉能离体萌发,萌发率普遍较低,为0.74%~49.65%。【结论】筛选出文心兰花粉离体萌发适宜的液体培养基组合及培养条件,不同文心兰种质资源的花粉离体萌发率存在明显差异,本研究结果可为后续文心兰种质资源的创新利用及他人研究等提供参考。

【Objective】Medium formulation and culture conditions were optimized for in vitro pollen germination of Oncidium spp.【Methods】On a liquid culture medium,in vitro germination rates of the pollens collected from the flowers of various Oncidium germplasms on the day of full bloom were determined.Based on the effects of sucrose,H_(3)BO_(3),Ca(NO_(3))·4H2O,MgSO_(4)·7H_(2)O,and KNO_(3) on the germination rate,an orthogonal experiment was applied to optimize the medium formulation and culture conditions.Subsequently,on the optimized medium under selected conditions,in vitro pollen germination rates of 68 collected Oncidium germplasms were determined.【Results】The degrees of importance of the medium ingredients to the pollen germination were found to be H_(3)BO_(3)>Ca(NO_(3))·4H2O>sucrose>MgSO_(4)·7H_(2)O>KNO_(3).The optimized formulation consisted of 100 g·L^(-1) of sucrose,10 mg·L^(-1) of H_(3)BO_(3),50 mg·L^(-1) of Ca(NO_(3))·4H2O,20 mg·L^(-1) of MgSO_(4)·7H_(2)O,and 30 mg·L^(-1) of KNO_(3).The pollen culture was conducted at 25℃ for 48h in darkness to deliver a generally low germination rate of 0.74% to 49.65% on 60.29% of the Oncidium germplasms.【Conclusion】The liquid medium and culture conditions for an in vitro pollen germination of Oncidium were optimized.The germination rates differed significantly among the species.