Cytological Evaluation of Some Tea (Camellia sinensis) Genotypes in Iran

To investigate karyotipic variation in tea genotypes, karyotype of 16 tea genotypes were studied. Chromosomal parameters including total length of the chromosome, long arm, short arm, arm ratio and centromeric index were measured and analysed. Analysis of variance showed significant variation among genotypes in total length of chromosomes, length of long and short arms. The results of karyotypic formula showed that the chromosomes were metacentric and sub-metacentric. The satellites and nucleotide organizer regions were observed in genotypes 277 and 581. Except for the genotype 2021, which was triploid (2n = 3x = 45) and is reported for the first time, the remaining 15 genotypes were diploid (2n = 2x = 30). Based on karyotypic analysis and classification of karyotypes, genotypes 277 and 444 were classified 1B and 2B, and 14 genotypes were classified in classes 1A and 2A. Thus genotypes 277 and 444 were asymmetric. Principal component analysis based on karyotypic parameters showed that total length of chromosomes and length of long arm played the most important role in the first component. The first component explained 54.83% of total karyotypic variation. Cluster analysis also classified the genotypes into five groups.