两种寄生植物营养器官结构的研究

研究了槲寄生和北桑寄生茎、叶和吸器的结构，结果表明：槲寄生三年生茎稍肉质化，无周皮，有极厚的角质层；皮层有7个纤维束，薄壁组织发达；木质部中亦含有大量薄壁组织；韧皮部发达；簇晶及大量粘稠物质在茎中广泛分布。槲寄生叶肉质化，厚1.44 mm; 角质层发达，厚度为9.06～13.4 μm;叶肉无栅栏组织和海绵组织的分化。北桑寄生茎与正常木本植物茎的结构相似，木质部为典型的环孔材；韧皮部含有石细胞；髓部细胞壁厚，单纹孔明显。北桑寄生叶较薄，叶脉发达，无栅栏组织和海绵组织的分化。两种植物的吸器结构相似，由薄壁组织和螺纹导管组成，它们的螺纹导管长度相同，但槲寄生导管的直径是北桑寄生的2.5倍。

The anatomic research on vegetative organ in two parasite species of Loranthaceae

The stem, leaf and haustrum structures were studied in Viscum coloratum and Loranthus tanakae. The triennium stem of Viscum coloratum was a little bit cerneous, no periderm with thick cuticula; cortex had 7 vescular bundles with developed parenchyma; xylem had large amount of parenchyma; phloem developed well; druse and merlicera spread widely in stem. The leaf of Viscum coloratum was cerneous and 1.44 mm thick, cuticula developed well and was 9.06~13.4 μm thick. Leaf had no differentiation of palisade and spongy. The stem of Loranthus tanakae had similar structure to that of normal ligneous, xylem being typical ring-porous wood, phloem with sclerotic, pith cell with thick wall and obvious simple pit. The leaf of Loranthus tanakae was thin and had no differentiation of palisade and spongy, vein developed well. The haustrum structure of the two were similar and both were composed of parenchyma and spiral vessel. Their spiral vessels were of the same length but the diameter of Viscum coloratum was 2.5 times than that of Loranthus tanakae.