茶树染色体组型分析

采用去壁、低渗、火焰干燥制样法分析了18个茶树品种的染色体组型,结果表明:茶树染色体以 X=15为基数,一般为二倍体,但也有非整倍体和多倍体细胞。不同品种、同一品种不同细胞的染色体组型不尽相同,其主要核型为2n=2x=30=18m+6sm+2sm~(sat)+4st~(sat)和2n=2x=30=18m+6sm+4sm~(sat)+2st~(sat)。根据组型分析结果,认为茶树起源于我国的西南地区,其品种间具有相近的亲缘关系,乔木型、大叶品种核型的对称性较高,是进化上较原始的品种。

The Analysis of Karyotype in Tea Plant

By usign wall degradation hydration flame drying method of preparing chromosomesamples in plants,18 karyotypes of sexual tea varieties and sexual offsprings from asexual line were observed.All of the varieties were diploid,2n=2x=30,but inHainandaye variety a few autoploid cells were found and in Jianghuatianchavariety a tetraploid was found.In all the varieties aneuploid cells with less than 30chromosomes were observed,but no B-chromosome was found.There were differenceof the karyotypes between the varieties or even between the cells.The main karyotypeswere 2n=2x=30=18m+6sm=2sm~(sat)+4st~(sat)and 2n=2x=30=18m+6sm+4sm~(sat)+2st~(sat).In the 15 pairs of tea chromosomes,only 3 to 4 pairs of sm or st chromosomescarried the satellites.A karyotype comparison between tea karyotypes and other plantsof genus Camellia showed that the later were more symmetrical.No absolute differenttypes of karyotype among all the tea varieties were found,so in taxonomy they shouldbelong to genus Camellia,Camellia sinensis(L.)O.Ktze.