中文摘要：

为确定铁皮石斛试管种苗的分级标准,测定了不同生长时期试管苗及移栽苗的生长指标,利用主成分分析法确定移栽或作为种苗流通的8月龄试管苗指标主成分,利用聚类分析建立分级标准,并对分级后移栽的试管苗生长情况进行评价。结果表明：以苗高、茎粗、叶数、叶宽和根长作为分级指标,8月龄铁皮石斛试管苗可以分为3个等级。分级移栽的试管苗较混合移栽在成活率、苗高、茎粗、叶数、鲜重等方面均得到显著提高。因此,可以把这一分级标准应用于铁皮石斛种苗的流通和规范化种植等方面。

英文摘要：

In order to set the grading standards of D.officinale test-tube plantlets,the growth indexes of the test-tube plantlets and transplanted plantlets were determined at different growth stages,the indexes＇ principal components of 8-month-old test-tube plantlets used for transplanting or marketing were fixed by principal component analysis,and the grading standards were established by cluster analysis.Also the growth performance of the test-tube plantlets transplanted after graded was evaluated.The results showed that based on plant height,stem diameter,leaf number,leaf width and root length,the 8-months-old test-tube plantlets could be divided into three grades,and the test-tube plantlets transplanted after graded were significantly better than those transplanted without gradation（P0.05）in terms of survival rate,plant height,stem diameter,leaf number and fresh weight.So this grading standards could be applied to the standardized production and marketing of D.officinale plantlets.