甜菊含甙量的变异及R－A型良种的选育

Studies on the variation of steviosides content and selection of type R -A in Stevia rebaudiana

从甜味成分种类及含量的不同，研究甜菊（ＳｔｅｖｉａｒｅｂａｕｄｉａｎａＢｅｒｔｏｎｉ）实生群体和单株无性系的变化，从中选育优质甜味成分含量高的良种。主要结果：（１）在实生群体中，丰产株型（圆纺锤形株）占７．３％，其中，优质甜味成分Ｒ－Ａ含量超过Ｓｔ含量的Ｒ－Ａ型株占１０．９６％，它们的Ｒ－Ａ含量变幅为３．３～１２．０％。（２）Ｒ－Ａ型良种Ｊ－２单株无性系在繁殖达２０００万株时，叶片大小和含甙量均存在极显著差异，Ｒ－Ａ含量变幅为４．５～１２．２％。（３）从Ｒ－Ａ含量为３．８６％的实生群体中选出Ｒ－Ａ含量为７．０４～１２．０３％的单株及从Ｒ－Ａ含量为９．１０％的良种单株无性系中选出Ｒ－Ａ含量为１０．１５～１２．１５％的单株，它们的Ｒ－Ａ含量均大幅度提高。

he present paper deals with the investigation on the seedling population and clone variation from the difference of sweet component and content in Stevia rebaudiana Bertoni,improved types of high content of Rebaudioside A(R-A)was selected.The results showed:(1)There are 7.3%high yielding plants in seedling population,in which the proportion of R-A type with content of R-A over St content is 10. 96%,and their R-A content varies from 3.3 to 12.0%;(2)Among the selected improved clone J-2,there are high significant difference in leaf size and steviosides content.The R-A content varies from 4. 5 to 12.2%,(3) The individuals with R-A content of 7. 04～ 12. 03%from seedling population(original content 3. 86%)and individuals with R-A content of 10.15～12. 15%from improved individual clone(original content 9.10%)were selected out.