碳源和光量对驱蚊香草组培苗生长及叶绿体超微结构的影响

Effects of carbon sources and light density on the growth and chloroplast ultrastructure of Pelargonium odoratissmum in vitro.

碳源和光量对组培苗的生长和品质具有重要影响,但环境中的CO2和培养基中的糖等碳源对组培苗生长效应的研究结果不一。该文以驱蚊香草组培苗为材料,在培养基不同糖含量(无糖和有糖)的基础上,设置不同CO2和光量(PPFD)组合参数并定量调控,寻找相互关联的环境因子的最佳组合,进一步探讨CO2、PPFD和糖对驱蚊香草组培苗生长和叶绿体超微结构的影响。研究结果表明:CO2与PPFD对组培苗的生长具有协同作用。在协同调控CO2和PPFD的条件下,培养基中的糖抑制组培苗的光合作用和生根,降低叶绿素含量,不利于叶绿体的正常发育;无糖培养能更好地促进生长和生根,光合速率最高,叶绿素和类胡萝卜素含量以及根系活力最大,叶绿体发育良好。在无糖培养时,CO2浓度和PPFD的控制参数在前期和后期分别取4 500μmol/mol、130μmol/(m2.s)和5 500μmol/mol、160μmol/(m2.s)。

Carbon sources and light density have significant effects on growth and quality of plantlets in vitro.However,the effects of carbon sources including sugar and CO2 on the growth of plantlets are still ambiguous.CO2 concentration and light density（PPFD） on the basis of sugar-added and sugar-free medium were controlled to find the best combination of environmental factors and further investigate the effects on the growth and chloroplast ultrastructure of Pelargonium odoratissmum plantlets.Results show that CO2 and PPFD play synergistic role on growth of P. odoratissmum.When CO2 and PPFD are increased in cooperation,the sugar-added medium inhibits the development of chloroplast,rooting, and photosynthesis.On the contrast,the sugar-free medium promotes growth and rooting of P.odoratissmum and photosynthetic rates,pigment content and root vigor are higher than other treatments.Chloroplast develops well in sugar-free medium.The best combination of CO2 and PPFD are 4 500 μmol/mol,130 μmol/（m^2·second） in initial,and 5 500 μmol/mol,160 μmol/（m^2·second） in later on sugar-free medium.