Isozyme Diversity in North American Cultivated Red Clover

Abstract

per locus, 53.3% polymorphic loci, and the amount of among-population genetic variation was much smaller Red clover (Trifolium pratense L.) is a forage legume with considthan the within-population variation. The objective of erable economic importance in world agriculture. Knowledge of the this study was to assess genetic diversity in North Ameriamount and distribution of genetic variability within a species is vital to breeders and geneticists when selecting breeding germplasm. The can red clover cultivars on the basis of isozyme data.objectives of this study were to assess genetic diversity in 34 North American red clover cultivars by means of isozymes. Isozymes assayed MATERIALS AND METHODS were esterase, ␤-glucosidase, phosphoglucomutase, peroxidase, di-Seeds of 34 red clover cultivars (Table 1) were obtained aphorase, phosphoglucoisomerase, and superoxide dismutase. Eleven from the USDA-ARS Plant Introduction Stations at Pullman of the 13 loci (84.62%) were polymorphic in at least one cultivar. (W-6), WA, and Griffin (S-9), GA. Eighteen plants of each Percentage polymorphic loci within cultivar ranged from 61.54% in accession were grown in pots filled with potting soil in a greencv Morred, Persist, and Redland II to 84.62% in cv Arlington, Ram, house. and Red Baron, with an overall mean of 73.98%. At the species level,

Analysis of genetic diversity in the core collection of red clover (Trifolium pratense) with isozyme and RAPD markers

“…For wild red clover populations Semerikov et al (2002) found H e values that ranged from 0.128 to 0.196 and P ranging from 0.41 to 0.52 and Mosjidis et al (2003) reported P= 74, A = 1.7 and H e = 0.323. For cultivated red clover Kongkiatngam et al (1995) reported H e values ranging from 0.10 to 0.12 in a comparison of two different cultivars and for 34 cultivars of red clover Yu et al (2001) observed mean values of P = 74, A = 1.59 and H e = 0.285. For the same core collection Mosjidis and Klingler (2006) reported average mean of P = 77.5, A = 1.66 and H e = 0.316.…”

“…A breeding program aimed at the creation of regionally adapted cultivars and the development of local seed production was therefore initiated at the Federal University of Rio Grande do Sul (UFRGS). Many studies using morphologic (Kouamé Analysis of genetic diversity in the core collection of red clover (Trifolium pratense) with isozyme and RAPD markers and Quesenberry 1993, Christie andChoo 1991, Bulinska-Radomska 2000), molecular (Kongkiatngam et al 1995, Campos-de-Quiroz and Ortega-Klose 2001, Kölliker et al 2003, Greene et al 2004, Herrmann et al 2005, Sato et al 2006) and biochemical traits (Hagen and Hamrick 1998, Yu et al 2001, Mosjidis and Klingler 2006 have demonstrated high genetic diversity, both among and within red clover populations. In view of the current interest in sustainable agriculture, red clover seems promising, since cultivated legumes play an important role in atmospheric N fixation and air and water pollution reduction (Rochon et al 2004).…”

“…However, the collection was investigated by only few studies using morphologic Boe 2002, Bortnem andBoe 2003) or biochemical traits (Mosjidis and Klingler 2006). Knowledge of the amount and distribution of genetic variability within a species is vital to plant breeders when selecting germplasm to be included in a breeding program (Yu et al 2001). But when only one or few traits are used to characterize collections, there is little opportunity to understand relationships among different traits within collections (Brown 1989).…”

“…However, RAPD markers are largely limited in the analysis of population structure since a complete genotypic determination is hampered by their dominant nature (Lynch and Milligan 1994). In contrast, isozymes as codominant markers are useful to estimate the allelic frequency and population genetic parameters and have proved reliable in genetic studies with red clover natural populations (Hagen and Hamrick 1998, Lange and Schifino-Wittmann 2000, Semerikov et al 2002, Mosjidis et al 2003 and cultivars (Kongkiatngam et al 1995, Yu et al 2001. Different aspects of the diversity can be analyzed by the use of molecular and biochemical markers.…”

Genetic variability of isoflavones in the USDA red clover core collection

“…Many works using morphologic (Christie & Choo, 1991;Kouamé & Quesenberry, 1993), molecular (Greene et al, 2004;Sato et al, 2005;Dias et al, 2008a) and biochemical traits (Yu et al, 2001;Mosjidis & Klinger, 2006) have showed the high genetic diversity present in this species. All red clovers may be grouped into three divisions corresponding to early, medium and late maturity types (Bird, 1948;Taylor & Smith, 1995).…”