3种入侵杂草次生木质部的细胞结构

运用离析法和显微照相等技术,比较了黄顶菊、豚草、加拿大一枝黄花3种入侵植物茎和根中次生木质部细胞的特征。结果表明,3种入侵植物根、茎的次生木质部中孔纹和网纹导管分子较多,具多尾性,单穿孔板,少数导管分子还具侵填体等特征,这都在一定程度上说明3种植物在系统进化中占有较高的地位。同一种植物中茎的导管分子平均长度长于根中,平均宽度宽于根中,且均达极显著差异;同一种植物的茎中和根中导管分子的长度、宽度并不一定有一致性。管胞细胞、纤维细胞的平均长度和宽度在3种植物间均未表现出一定的规律性。这些现象都说明植物为了更好的适应不同的生活环境而形成了一定的结构。

The Study of the Cell Structure in the Secondary Xylem in Three Invasive Plant Varities

The characteristics of secondary xylem cells of the stems and roots in three invasive plant varities,Flaveria bidentis,Ambrosia artemisiaefolia var. elatior and Solidago decurens Lour were stud- ied. The results showed that there were many Profile vessel elements and Netted vessel elements in the secondary xylem vessel elements in the roots and stems of the three invasive plants. A small numher of vessel elements had filling characteristics, which, to a certain extent,showed that the three plants occupy a higher position in evolution. The stem vessel of the same plant is longer and wider than the average length and width of that in the roots,and the difference is significant. The length,width of the vessel elements in the stems and roots in the same plant are not always the same. The average length and width of Tracheid cells and Fiber cells in the three plants did not show certain regularity. These phenomena showed that plants have developed certain structures to better adapt to different living environment.