外施CO_2时光照度对大花蕙兰试管苗生长和叶片气孔特征的影响

Effects of light intensity on the growth and leaf stomata characteristics of Cymbidium hookerianum shoots in vitro under CO_2 enrichment

以大花蕙兰(Cymbidium hookerianum)为试材,在外施CO2条件下使用CP培养容器,比较不同光照度(14.4,30.6,54.0μmol.m-2.s-1)对大花蕙兰试管苗生长和叶片气孔特征的影响.结果显示,改善CP容器内CO2浓度水平后,提高光照度可明显促进大花蕙兰试管苗的生长.高光照度(54.0μmol.m-2.s-1)下培养的试管苗与标准光照度(30.6μmol.m-2.s-1)相比,气孔密度虽较低,但其形态指标、叶绿素指数、气孔器大小和面积等重要测定指标却有明显提高;与低光照度(14.4μmol.m-2.s-1)相比,高光照度下培养的试管苗除株高、叶数、根长和气孔密度外,其它重要指标也均有明显提高,表明外施CO2条件下高光照度对促进大花蕙兰试管苗的生长和提高其品质效果明显.

The Cymbidium hookerianum plantlets were used as experiment material cultivated by culture panle with rookwnt system （CP · RW） to study the effect of light intensity on the growth and leaf stomata characteristics of in vitro shoots under CO2 enrichment. The results showed, the improvement of CO2 concentration in the CP and increasing the light intensity could significantly promote the plantlets growth of C. hookerianum. Compared with standard light intensity （30.6 μmol·m^-2·s^-1） , there existed a significant improvement in such important indexes as morphological indexes, SPAD val- ue and leaf stomata size in the high light intensity （54.0μmol·m^-2·s^-1） except the leaf stomata density. Compared with low light intensity（ 14.4μmol·m^-2·s^-1 ）, except such indexes as plant height, leafes number, root length and leaf stomata density, there also existed a significant improvement in other important indexes between the high light intensity and low light intensity. The above results indicated that CO2 enrichment had evident effect on the improvement of growth and quality of C. hookerianum plantlet cultivated in the high light intensity.