香石竹组培苗与温室苗叶表皮气孔特征比较

Comparison of leaf epidermal features of carnation plantlet grown in vitro and greenhouse

为了研究香石竹组培苗与温室苗叶表皮气孔特征。采用过氧化氢—醋酸离析法,对香石竹试管正常苗、试管玻璃化苗及温室苗的叶片上、下表皮进行制片观察比较。结果表明:3类苗表皮细胞形状及气孔类型相似,其表皮细胞形状为多边形,垂周壁式样平直、弓形,气孔散生于上、下表皮细胞当中;气孔形状、气孔密度等具有显著差异。气孔形状:试管正常苗的呈圆形,玻璃化苗的保卫细胞过度弯曲形态异常呈扁圆形,温室苗的呈椭圆形;气孔密度表现为温室苗>试管正常苗>试管玻璃化苗;气孔相对开张度则相反,玻璃化苗的最大,是试管正常苗的2.36倍,试管正常苗是温室苗的2.56倍。从解剖学角度揭示了试管正常苗在移栽驯化期间易失水萎蔫和不易成活,试管玻璃化苗在继代培养中不能正常生长,极易死亡的原因。

In order to investigate the leaf epidermal features of carnation plantlet grown in vitro andgreenhouse, the upper and lower leaf epidermis of carnation plantlet grown in tube （ in vitro ） , vitrified（ in vitro） and greenhouse were disposed using the hydrogen peroxide-acetic acid segregationmethod and observed with microscope. Results showed that three types of plantlet presented similarepidermal cell shape and stomatal patterns. The shape of epidermal cell was polygon, with straightor arched anticlinal wall. Stomata distributed between the upper and lower epidermis cells. Theshape, density and index of stomata showed significant variation. Normal in vitro plantlet showedround stomata. For vitrified in vitro plantlet, guard cells over bended and formed a flattened circularshape. Stomata shape of greenhouse plantlet was oval. Stomata density of greenhouse plantlet washighest while the lowest was in vitrified in vitro plantlet. However, relative opening degree of stomataof vitrified in vitro plantlet was biggest. It was 2. 36 times of normal in vitro plantlet and 2. 56times of greenhouse plantlet, respectively. It revealed why in vitro plantlet get dehydrate and wilteasily during the process of transplant and acclimatization. And this is the main reason that vitrified in vitro plantlet hardly grow normally and so easily dead.