Adaptation of Rhus chinensis to drought stress in karst area: Insights from anatomical structure of leaf

Leaf structure of Rhus chinensis in karst area is studied by paraffin sectioning and electron microscope and some xerophilous structures are found in leaf under water stress.The epidermis is covered by a thick cuticle.Upper epidermis cell is composite by a dense cuticular layer.Lower epidermis is covered by epicuticle hairs and the sunken stoma existed in lower epidermis.The palisade tissue is rich and the spongy parenchyma is loose.The ratio of the palisade tissue to the spongy parenchyma is about 4:1.Some mesophyll cells contained colloidal crystal material.Sclerenchyma in leaf vein is quite developed.Out of the xylem,there is lot of fiber and the tannin crystal distributes around the air cavity.It is then concluded that Rhus chinensis adapts to the karst drought environment with protection type.