叶用型杜仲苗期优良单株初选

A primary selection of the Eucommia ulmoides superior tree for leaf use

为了筛选出适合保定地区生境的优良叶用型杜仲单株,对来自河南、河北2个不同产地的30株2a生杜仲实生苗苗期的单叶面积、干重、鲜重、叶绿素含量、总黄酮含量及季节变化进行了比较研究,其中叶绿素含量与总黄酮含量的测定采用了分光光度法。结果表明:不同杜仲单株间的单叶面积、叶绿素含量、总黄酮含量等存在极显著差异,通过对叶面积、干鲜重比、总黄酮含量等指标进行主成分分析,最后从30株杜仲实生苗里初步筛选出5株优良单株,分别是N_(11)、N_9、B_2、B_(12)、B_(14);各单株叶中N_(11)总黄酮含量最多,为9.59%,其次为N_9,达到了9.08%,其中B_2、B_(12)叶绿素含量最高,分别为2.10mg/g、2.07mg/g,并且单株B_(14)干鲜重比高达0.78,加工成本最低;根据各单株苗期叶中总黄酮含量的季节变化可以看出,其总黄酮含量在7—8月份最高,因此可以选择7月中旬至8月中旬进行杜仲叶采收。

In order to select the Eucommia ulmoides superior tree for leaf use in Baoding area,seedling growth,leaf area,leaf dry weight,fresh weight and chlorophyll content,total flavonoids content and their seasonal variations of 30 different strains from two product regions Henan and Hebei were compared in this study.The content of chlorophyll and total flavonoids were determined by spectrophotometry.The results showed that there were significant differences in leaf area,chlorophyll content and total flavonoids content in different strains.Based on principal component analysis of leaf area,dry weight andtotal content of flavonoids,finally 5 superior strains were preliminarily selected from 30 Eucommia ulmoides strains.They were N（11）,N9,B2,B（12）,B（14）.The total flavonoids content was the highest in N（11） at 9.59%,followed by N9 at 9.08%.The chlorophyll content of B2 and B（12） was the highest,2.10 mg/g and 2.07 mg/g,respectively.And the dry fresh weight ratio of B（14） was as high as 0.78,which showed its processing cost is the lowest.According to seasonal variations of total flavonoids in the leaves of each seedling stage,the total flavonids content was the highest in July and August.It could be havested with Eueommia ulmoides from mid-July to mid-August.