三江源区野生草地早熟禾形态特征

通过对三江源区不同地区的居群,不同地理位置及不同海拔高度的野生草地早熟禾形态特征的分析,野生草地早熟禾种群的性状指标高度、茎节数、花序长、花序轴节数、小穗数总和、叶数、上部叶长、下部叶宽、上部叶宽、小穗长、小穗宽、上部叶长/宽、下部叶长/宽和小穗长/宽在青南5个地区有明显的差异性。随着海拔高度的升高,各形态特征的变化趋势可分为4类：①升高型：随着海拔高度的上升,高度,节数,小穗数,穗轴节数,小穗宽,下叶长/宽,上叶长/宽的变异系数都呈上升趋势;②下降型：随着海拔高度的升高,小穗总和数的变异系数呈下降趋势;③无规律型：随着海拔高度的升高,叶数的变异系数呈无规则变化;④抛物线型：随着海拔的升高,上部叶长,下部叶宽,小穗长,小穗长/宽的变异系数呈一抛物线型,起初升高,达到一最大值之后开始下降。可将5个地区的野生草地早熟禾分为久治型、达日型和玛沁型。

Morphologic Characters of Wild Poa pratensis in Region of Three - river Sources

The morphologic characters of wild Poa pratensis in different populations,defferent geograohic lacation and different height above sea level were observed and analysed.The results showed that there was significant difference in the trait indexes such as height.stem knob numbers,length of inflorescence,inflorescence knob numbers,sum of spikelet,leaf numbers,upper leaf length,bottom leaf width,upper leat width,spikelet length and width,upper leaf length/width,bottom leaf length /width and spikelet length/width of wild Poa ptatensis in five regions of the south area of Qinghai province,With increasing height above sea level,the change tend of every morphologic charactes was divided into four types：①Iifting type：with increasing height above sea level,the variation coefficient height,Knob numbers,spikelet,numbers,spikelet knob numbers,spikelet width,upper leaf Length/width,boteom leaf length/width was the rise tend.②declining type：with increasing height above sea level.the variation coefficient of sum of spikelet was decline tend.③non-regulation type：with increasing height above sea lerel.the variation coefficent of leaf numbers was non-regulation change.④parabola type：with increasing height above sea lerel,the variation coefficient of upper leaf length,bottom leaf width,spikelet length,spikelet length/width was the parabola type,which rised at the beginning,reached the maximun and then gradually declined.So the wild Poa ptatensis in five region could be divided into three types——Jizhi type,Dari type and Machin type.