两种罗布麻营养器官的解剖结构及其生态适应性

Anatomical research on nutritive organs of two species of Apocynum and their ecological adaptability

关键词:  罗布麻  营养器官  解剖结构

Key words:  Apocynum  nutritive organs  anatomical structure

摘要:

采用石蜡切片法，对红麻和大麻状罗布麻的营养器官进行解剖学观察。结果显示：（1）红麻和大麻状罗布麻叶片均为异面叶，叶片表皮均被不同厚度的角质层，气孔具孔下室，栅栏组织2层；红麻的栅栏组织比大麻状罗布麻的排列紧密，而海绵组织比大麻状罗布麻的排列疏松；大麻状罗布麻叶片主脉厚度平均值为489.61 μm，而红麻仅为369.29 μm，差异达到极显著；（2）红麻和大麻状罗布麻茎的维管束均属典型的双韧维管束结构；（3）红麻根的周皮层数(4～5层)比大麻状罗布麻的(5～7层)少，二者的皮层厚度平均值分别为698.23和744.11 μm，差异不显著；（4）二者根、茎、叶中富含大量分泌细胞。结果表明，2种罗布麻均具有适应干旱环境的能力，且大麻状罗布麻在宁夏地区引种栽培具有可行性。

Abstract:

The anatomical structure of nutritive organs of two Apocynum species(A.cannabinum L.and A.venetum L.)were studied by using the method of paraffin section. The results were as follows:(1)The leaf of two Apocynum species was bifacial. The leaf epidermal cell of two species had cuticle layer with different thickness. Substomatic chamber developed well. Both had two layers of palisade tissues. Compared with A.cannabinum，the palisade tissues of A.venetum arranged more tight，but spongy tissues more loose. Vein tissues of A.cannabinum developed well and the thickness of major vein was up to 489.61 μm，significantly thicker than that in A.venetum(369.29 μm). (2)The vascular bundle of stem for both Apocynum species typically belong to bicollateral bundle. (3)There were 4-5 layers of periderm cells in roots ofA.venetum，while 5-7 layers in A.cannabinum. There was a large root cortex tissue for both species.(4)A large number of secretory cells were observed in the roots，stems and leaves for both species. The anatomical investigation indicated that both the two Apocynum species were characterized as xeromorphism to cope with the arid environments.