Document Type : Research Paper
Authors
Abstract
Evaluation ofkaryotype, ploidy levels and chromosome numbers of daffodil (Narcissus sp.) plants was carried out on collected endemic genotypes from Southern Khorasan, Khouzestan, Kohgiloye – Boyerahmad, Fars, Mazandaran, Golestan provinces and exotic genotypes. The mitotic study karyotype and morphological characteristics of daffodils chromosomes was conducted on the meristematic cells of root tips from bulb. Initially the root tips were pretreated comparable with 8-hydroxyquinoline and ice water. Then they were fixed in ethanol: acetic acid (3:1) solution, hydrolyzed in HCl and stained with aceto-orsein. Three metaphase plates were used to analyze karyotype parameters of each genotype. OR-banding was carried out according to conventional methods. Chromosome numbers showed ploidy levels variation between genotypes. There was a direct relationship between chromosome number and ploidy levels of genotypes. Basic chromosome numbers of endemic and exotic populations were 10 and 7, respectively. Meskinak-e-Behbahan and meskinak-e-Ahvaz varieties were diploid 2n=2x=20 with karyotypic formula: 4m+5sm+1st, others were triploid 2n=3x=30 with 7m+3sm, white Holandi`s daffodil was tetraploid 2n=4x=28 with 2m+4sm+1st; others were triploid 2n=3x=21 with 1m+5sm+1st. Karyotype evaluation indicated that size and form of chromosomes were different. Also, ploidy levels were confirmed by flow cytometry method.
Keywords
)