高原芥三个居群的物种生物学特性

Species Biological Characteristics of Christolea crassifolia Camb. in Three Populations

运用居群生物学的原理和方法,对分布于帕米尔高原地区三个居群的高原芥(Christolea crassifolia Camb.)的染色体核型、花粉形态与叶表皮气孔形态进行了研究。结果表明,高原芥三个居群的染色体2n=14,基数为7;核型不对称系数均为1A型;花粉均具三沟萌发孔,沟长达两极,极面观均为具网状纹饰的三裂圆形,但在花粉形状、网眼直径及网脊宽度上均存在差异;叶上、下表皮细胞呈3～6条边组成的多边形,其垂周壁平直,上下表皮均有无规则的气孔分布,保卫细胞肾形,无副卫细胞,由此确定高原芥是十字花科系统演化上处于较古老位置或原始的类型。

The study was used to overally reveal pollen morphology and phenotypic characteristics of chromosome karyotype,pollen morphology,leaf epidermal pollen morphology and phenotypic characteristics from Christolea crassifolia Camb.in thee populations of Pamirs plateau region by use of the principle and method of population.Our results showed that in the three populations,chromosomes（2n） were 14,i.e.radix was seven.The dissymmetrical coefficients of karyotypes were 1A type.Three germinating holes were distributed in all pollens,channel reached two polars in cross section,and there were trifid roundness with meshy veins.However,there were difference in the pollen shape,grid mesh diameters and grid back width.The upper and lower epidermis of leaves were composed of polygon with three to six sides,their anticlinal walls were straight,stomata with kidney-shaped guard cells but without subsidiary cells were irregular on the surface of the upper and lower epidermis.This could be considered as a basis for classification.It was possible that the systemic evolution of Ch.crassifolia was antiquate or original in Cruciferae.