沙棘雌雄株叶片解剖结构比较研究

Comparison on Leaf Anatomical Structures betweenthe Female and the Male Plants of Eippophae rhamnoides L.

为了研究沙棘雌、雄株叶片的第二性征,本文采用石蜡切片法观察了沙棘雌、雄株叶片结构的差异。结果表明:(1)沙棘雌、雄株叶片均由表皮、叶肉和叶脉3部分组成,表皮均由1层细胞构成,表皮毛发达,上表皮有拟泡状细胞;叶肉栅栏组织与海绵组织分化明显。(2)雌株上表皮具更多的拟泡状细胞,其主脉韧皮部薄壁细胞及其下方的一些薄壁细胞含较多的后含物,下表皮的表皮毛更浓密;而雄株的叶片厚度、叶片上表皮厚度、栅栏组织厚度、栅栏组织厚度/海绵组织厚度均显著大于雌株,且其主脉维管束更发达。结果表明,沙棘雌雄株叶片解剖结构存在明显差异,这些差异是第二性征的表现,也是沙棘长期进化中形成的稳健的适应策略,可能有利于该物种的繁衍。

We observed the differences in leaf anatomical structure between the male and the female using paraffin method to investigate leaf secondary sex characteristics of Hippophae rhamnoides L.. Results showed that ： （ 1 ） Both the male and the female leaves consisted of epidermis, mesophyll and veins. The epidermis was composed of a layer of cells with developed trichomes, including similar bulliform cells in upper epidermis; the differentiation of palisade tissue and spongy tissue was obvious in mesophyll. （2）There were more similar bulliform cells in upper epidermis, more ergastic substances in some parenchymal cells of phloem and below the phloem, more trichomes in lower epidermis in the female plant than in the male one; the male plant were significantly higher than the female in leaf thickness, thickness of leaf upper epidermis, thickness of palisade tissue, thickness ratio palisade tissue/sponge tissue, and had more developed vascular bundle than the female in main vein. These results suggested that there were obvious differences in leaf anatomical structure between the female and the male plants of the species, and the differences were the performances of secondary sex characteristics, also robust adaptive strategy formed in the long-term evolution, which might be good for reproduction of the species.