Author/Authors :
Safari Hooshmand نويسنده , Abbaszade Soosan نويسنده Young Researchers and Elite Club, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran , Ashraf Jafari Ali نويسنده Research Institute of Forests and Rangelands, Tehran, Iran , Shirvani Hooman نويسنده Department of Agriculture, Payame Noor University, Iran
Abstract :
Genetic variations were studied for 13 accessions of Lolium multiflorum
using cytogenetical traits. Karyotype was prepared for 5 metaphases cells of
each accession and the traits of total length (TL), long arm (LA), short arm
(SA), arm ratio (AR) and centromer index (CI) were determined by micromeasure
software. Six accessions were diploid and seven accessions
were tetraploid, the basic chromosome number was x=7, and also three and
six satellites were observed for diploid and tetraploid accessions, respectively.
The accessions had an asymmetry karyotype, and variations were significant
(at 1% level of probability) between accessions for karyotypic characters
based on analysis of variance (ANOVA). Results of mean comparison
showed that the diploid accessions had higher mean chromosome length
than tetraploid accessions. The results of cluster analysis by Wardʹs method
based on the values of intrachromosomal asymmetry index (A1) and interchromosomal
asymmetry index (A2) showed that the studied accessions
were fallen in three groups. The tetraploid accessions had higher intrachromosomal
asymmetry than the diploid accessions. Principal components
analysis based on karyotypic traits for accessions showed the first two components
captured 84.37% of the total variance. Principal component analysis
for grouping accessions based on Scatter plot identified four distinctive
groups.
