A cytogenetic study of some species of Trifolium in Eestern Azarbayjan province

The species of Trifolium differ from each other based on morphology and cytogenetic characters. For study of karyotype variation, 11 species of Trifolium were selected from North-West in Iran and karyological study was performed on number, size and type of chromosomes. Results of karyological studies in root tip samples showed that nine species were diploid with x=7 or 8 and two species were tetraploid with x=8. Based on A₁, A₂, TF%, SC and formula of karyotype T. pratense and T. canescens had much symmetrical karyotype. Analysis of variance for seven karyotype characters (L, S, L/S, CI, DRL, L+S, and TL) based on randomized complete design with five replications was performed. The results showed significant differences between the species (p<0.1). T. canescens had the highest total length (L+S), long (L) and short arm characters. For arm ratio (L/S) trait, T. hybridum had thehighest and for CI T. pratense showed the highest average values. Also the highest DRL value was, obtained in T. arvense and the highest TL value was obtained in T. ambiguum and T. repens. Cluster analysis divided the species into 4 groups. The highest metric distance was obtained between T. canescens and T. hybridum, and lowest metric distance values were obtained between T. phleoides and T. striatum. The species which located in same group have similar karyotype, so they can be used in interspecific crossing.