Cluster analysis of a world collection of red clover germplasm

Abstract

Germplasm evaluation data on more than 800 accessions of red clover (Trifolium pratense L .) representing 41 countries of origin were examined from the Germplasm Resource and Information Network of the National Plant Germplasm System . Large variations exist for most characters over all origins . Clustering accessions using standardized values of 15 morphological and physiological descriptors produced three distinct groups that correspond to early, medium, and late maturity groups . Within each maturity group, different similarity groups were produced . The analysis revealed a large range of diversity among the red clover accessions over all origins with the most diversity occurring in accessions from Eastern and Northern Europe . Accessions with similar attributes often were from countries with contrasting agroecological conditions . Categorizing red clover accessions into similarity groups provided a structure for sampling a limited number of entries to represent the diversity of the germplasm into a core collection . The utilization of this core collection should facilitate genetic resource management and identification of genotypes for breeding and other agronomic uses .

Molecular characterization of red clover genotypes utilizing microsatellite markers

“…Dugar and Popov (2013) have studied 15 Ukrainian red clover cultivars and found that the among-group genetic variability of SSR markers was low and that it amounted only 6.9% of the total variability. Gupta et al (2016) analyzed a core collection of red clover which was established by (Kouame and Quesenberry, 1993), and dismantling of the genetic variance using AMOVA showed that most of the genetic diversity was contained within the population (91%), while 9% of genetic variation is accounted for amonggroup variability. Berzina et al (2008) were studying seven diploid red clover cultivars based on six SSRs and found that inter-group variation represented only 2% of the total genetic polymorphism, as well as that Φ ST values (0.006 to 0.043), indicated a low genetic differentiation between varieties.…”

“…Development and breeding of new varieties of red clover and similar forage legumes such as alfalfa is a very slow and long process (Tucak et al, 2009). In addition, it is still insufficiently studied genetic variability of both natural populations and local populations of forage species, such as red clover, in which is a fairly widespread use of local populations (Kouame and Quesenberry, 1993;Dias et al, 2008).…”

Legume Crops Phylogeny and Genetic Diversity for Science and Breeding

“…Other important questions that need to be examined in order to determine the global ex situ coverage of Trifolium include the extent to which current collections represent an appropriate level of geographical coverage around the globe and to what degree the major collections are sampling independent geographical regions (Abberton and Thomas, 2011). The study of variation in clover germplasm collections based on morphological, phenological, and agronomical characters and molecular markers has resulted in the development of core collections (Kouame and Quesenberry, 1993;Vymyslický et al, 2010Vymyslický et al, , 2012. No concordance between morphologic and RAPD marker classification of wild red clover populations was also reported by Greene et al (2004).…”

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).…”

“…This core collection was originated from the analysis of more than 800 accessions present in the Germplasm Resource and Information Network of the National Plant Germplasm System (GRIN-NPGS). The cluster analysis of these accessions using standardized values of fifteen morphological and physiological descriptors produced distinct groups that correspond to early, medium, and late maturity groups (Kouamé & Quesenberry, 1993). The accessions from the core collection were also classified by the GRIN-NPGS (http://www.ars-grin.gov/npgs/acc/acc_queries.…”