不同品种茶花在干旱胁迫下叶 片气孔和蜡质的差异化表现

Leaf Stomata and Wax of Different Tea Flowers were Differentiated Under Drought Stress

摘要:

摘要：以茶花品种?十八学士'和?情人节'为研究对象，在塑料大棚室温15～25℃下，采用盆栽控水法进行干旱胁迫，利用扫描电子显微镜观测叶片的表皮结构。研究不同品种在干旱胁迫下，叶片表皮结构的差异对抗旱性的影响，为茶花的栽植管护推广和造景应用提供基础性的理论依据。 结果表明，茶花叶片仅有下表皮具有气孔，上、下表皮都有不同程度量的蜡质附着物。随干旱胁迫程度的加重，气孔开合及蜡质积累出现差异性变化。抗旱性较差的品种，主要通过利用蜡质的合成、堆积来堵塞气孔，降低蒸腾作用。抗旱性较强的品种，气孔的保卫细胞在干旱早期就启动闭合响应机制，叶片上表面的蜡质堆积程度更强，能更好的保护叶片免受光照和有害物质的伤害，说明叶片表皮结构对于茶花抗旱性强弱的决定作用较大。

Abstract:

Abstract: In this study, the tea flowers cultivars Camellia japonica ?shibaxueshi'and Camellia japonica ?qingrenjie' were used as the research objects. The epidermal structure of leaves was observed by scanning electron microscope (SEM) under drought stress in plastic greenhouse at room temperature of 15～25℃.The aims were to study the effect of leaf epidermis structure difference on drought resistance of different varieties under drought stress, and to provide basic theoretical basis for the promotion of camellia planting management and landscaping application. The results showed that only the lower epidermis of the leaves of had stomata, while the upper and lower epidermis had wax attachments of various amount. Stomatal movement and wax accumulation varied as drought stress progressed. The varieties with poor drought resistance mainly used wax synthesis and accumulation to block stomata and reduce transpiration. In the cultivars with high drought resistance, the guard cells of stomata started the closure response mechanism at the early stage of drought stress, and the wax accumulation on the upper surface of leaves was more prominent, protecting leaves from damage of light and other harmful substances. These results indicate that the leaf epidermis structure plays a more decisive role in drought resistance of C. japonica.