Assaying polymorphism at DNA level for genetic diversity diagnostics of the safflower (Carthamus tinctorius L.) world germplasm resources

Abstract

Carthamus tinctorius (2n = 2x = 24), commonly known as safflower, is widely cultivated in agricultural production systems of Asia, Europe, Australia, and the Americas as a source of high quality vegetable and industrial oil. Twenty-two RAPD primers, 18 SSR primers, and 10 AFLP primer combinations were used to assess: (1) the genetic diversity of 85 accessions (originating from 24 countries) representing global germplasm variability of safflower and (2) the interrelationships among safflower 'centers of similarity' or 'regional gene pools' proposed earlier. The RAPD and SSR primers and AFLP primer combinations revealed 57.6, 68.0, and 71.2% polymorphism, respectively, among 111, 72, and 330 genetic loci amplified from the accessions. The sum of effective number of alleles (66.44), resolving power (59.16), and marker index (51.3) explicitly revealed the relative superiority of AFLP as a marker system in uncovering variation in safflower. Overall, AFLP markers could recognize 'centers of similarity' or 'regional gene pools'. Analysis of molecular variance and Shannon's information index provided corroborating evidences for the present and previous studies that concluded fragmentation of safflower gene pool into many gene pools. Divergent directional selection is likely to have played an important role in shaping the diversity. From the practical applications standpoint, the diversity of Iran-Afghanistan gene pool is very high, equivalent to the total diversity of the species. The Far East gene pool is the least diverse. The present comprehensive input, first of its own kind in safflower, will assist marker based improvement programmes in the crop.

Efficacy of RAPD, ISSR and DAMD markers in assessment of genetic variability and population structure of wild Musa acuminata colla

“…Discriminatory power of each of the three markers (RAPD, ISSR and DAMD) was evaluated by means of three parameters, viz. Polymorphic information content (PIC), the probability in detecting polymorphism by a primer or primer combination between two randomly drawn genotypes was calculated using the formula PIC=1-Σpi 2 , where pi is the frequency of the ith allele (Sehgal et al 2009); Resolving power (Rp) which is the ability of each primer to detect level of variation between individuals was calculated according to Prevost and Wilkinson (1999): Rp=ΣIb where Ib (band informativeness) takes the values of: 1-[2|0.5-p|], where p is the proportion of individuals containing the band, and marker index (MI) for each primer was also calculated as a product of two functions -the polymorphic information content and effective multiplex ratio (EMR) (Varshney et al 2007) i.e., MI=PIC×EMR.…”

Genetic Diversity Analysis of Safflower (Carthamus tinctorius) Accessions from Different Geographic Origins using ISSR Markers

“…It has been planted since ancient times both as a dyestuff and as oil crop in a wide range of geographical regions (Knowles, 1989). It is cultivated in some regions of Europe, Australia, Asia, and the Americas to produce high quality vegetable and industrial oil (Sehgal et al, 2009). Nowadays, it is cultivated mainly for its seed, which is used as source of edible oil and as birdseed (Dajue and Mündel, 1996).…”

Genetic characterization of Iranian safflower (Carthamus tinctorius) using inter simple sequence repeats (ISSR) markers

“…It is an annual and predominantly self-pollinated species and it is one of the world's oldest oil seed crops (Sehgal et al 2009). It is believed to have been domesticated somewhere in the Fertile Crescent region over 4,000 years ago (Knowles and Ashri 1995).…”

“…Amplified fragment length polymorphism (AFLP), isozymes, simple sequence repeats (SSR), random amplified microsatellite polymorphisms (RAMP), random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) have all been used to determine genetic diversity in plant populations (Wang et al 1994;Godwin et al 1997;Hollngsworth et al 1998;Blair et al 1999;Amsellem et al 2000;Mengoni et al 2000). Microsatellites or simple sequence repeats are tandemly repeated mono-, di-, tri-, tetra-or pentanucleotide units (Sehgal et al 2009). …”