| The objective of the study is to elucidate the differences among the leaf structures of longan cultivars. Taking Dimocarpus
longan Lour. 'Chuliang', D. longan Lour. 'Dawuyuan', D. longan Lour. 'Fuyan', D. longan Lour. 'Guihua', D. longan Lour. 'Shixia' as
materials, and they were compared under paraffin section, scanning election microscope and maceration. The leaf structure parameters were measured and analyzed. The results showed that the leaf was typical bifacial, the upper and lower epidermis were consisted of monolayer of cells, the upper epidermis cells arranged regularly, the lower epidermis cells were uneven; the lower epidermis was covered with numerous mammillae, each mammilla was composed of a number of tubular cells; stomas were few and only distributed on lower epidermis, mainly near lateral veins. Leaf thickness, horny layer thickness and stoma long axis of five longan cultivars had no significant
difference. The thickness of upper epidermis cells, palisade tissue, spongy tissue, and the value of palisade tissue thickness/spongy tissue thickness, mammilla density, stoma short axis had significant differences among different longan cultivars. It was only a few stomas that we
observed on the lower epidermis of the leaves. The lower epidermis was covered with numerous mammillae. The results can provide basis for the identification and development of longan germplasm resources. |
