“桂橙一号”的遗传鉴定

＂桂橙一号＂成熟果实风味浓郁,为探明＂桂橙一号＂的亲本,本研究应用倍性检测、形态学标记和AFLP、SSAP等分子标记对其进行遗传鉴定。倍性检测证实＂桂橙一号＂为二倍体。形态学观察表明,其叶形指数、气孔密度、气孔纵径与冰糖橙的差异显著,叶形比冰糖橙更接近椭圆,气孔密度更高。SSAP标记显示,＂桂橙一号＂与冰糖橙相比存在1个多态性位点。通过对差异片段的回收、测序及序列比对结果表明：该差异片段长102bp,与柑桔抗CTV基因同源性高达87%。表明＂桂橙一号＂是不同于冰糖橙的芽变新种质,可以直接作为品种资源加以利用。

Genetic Identification of Guicheng No.1(Citrus sinensis(L.)

The flavor of Guicheng No.1（Citrus sinensis（L.） mature fruit is of rich flavor.This study was to clarify the possible parents of Guicheng No.1 via ploidy analysis,morphological markers,and molecular markers including amplified fragment length polymorphism（AFLP）,sequence-specific amplification polymorphism（SSAP）.Ploidy analysis confirmed that ‘Guicheng No.1 was a diploid.There were significant difference in the phylliform index,the stoma density and stomatal longitudinal diameter between Guicheng No.1 and ‘Bingtang’sweet orange,but was not in the transverse diameter.In morphology,the phylliform of‘Guicheng No.1 was almost elliptical,with higher stoma density and different stoma size.SSAP analysis indicated that polymorphism locus existed between Guicheng No.1 and‘Bingtang’sweet orange.We have found the fragment with polymorphisms and sequenced it.The results showed that a piece of DNA 102 bp in length had 87% of homologous to the CTV resistance gene according to the genbank data.It suggested that Guicheng No.1 should be distinct from ‘Bingtang’sweet orange.It was a mutant and can be used as a new cultivar.