Analysis of genetic diversity of Tunisian caprifig (Ficus carica L.) accessions using simple sequence repeat (SSR) markers

Abstract

BackgroundThe common fig (Ficus carica L.) is a gynodioecious species with two sexual forms: male trees (caprifigs) with male and female flowers and female trees that produce only female flowers that will result in the edible fig syconium. In this study the genetic diversity of 20 Tunisian accessions of caprifig is analyzed using SSR markers previously developed for this crop.ResultsThe results revealed that the 13 pairs of primers used amplified a total of 37 alleles in the accessions studied. The number of alleles per locus ranged from two to six, with a mean value of 2.85 alleles per locus. Observed and expected heterozygosities showed mean values of 0.33 and 0.29 respectively. UPGMA cluster analysis and Principal Component Analysis grouped the caprifig accessions analyzed in three groups.ConclusionThe results obtained show a low genetic diversity in the Tunisian accessions of caprifig studied and, in spite of analyzing samples from different geographic regions, no clear groupings based on geographical origin are observed suggesting widespread exchange of caprifig plant material through vegetative propagation among different areas in Tunisia.

Assessment of Genetic Relationship among Male and Female Fig Genotypes Using Simple Sequence Repeat (SSR) Markers

“…Aradhya et al (2010) reported that the number of alleles ranged from 4 (LMFC22, LMFC31 and LMF35) to 9 (LMFC30) with a mean of 4.9. Similar results were also obtained by Essid et al (2015) with 20 caprifig accessions that the number of alleles per locus ranged from 2 (LMFC32, LMFC15, LMFC21, LMFC31, LMFC18, LMFC27, LMFC23) to 6 (LMFC30). Thus, results from present study and previous demonstrated that LMFC30 produced the highest number of alleles per locus.…”

“…A heterozygote excess (Ho>He) was observed for the LMFC15, LMFC31, LMFC18, LMFC27 loci whereas a heterozygote deficiency (Ho<He) was observed in LMFC24 and MFC2 loci in a study dealing with genetic variation of caprifigs (Essid et al, 2015). According to Giraldo et al (2008), for all SSRs except LMFC15 and LMFC21, Ho values were higher than the expected.…”

“…Among 47 genotypes, 82 polymorphic SSR alleles were amplified, and the average number of alleles per SSR marker was 3.56 (Table 2) In another study assessing genetic variation among caprifig cultivars, it was reported that the average He and Ho values were 0.29, 0.33, respectively (Essid et al, 2015). On the other hand, Khadari et al (2004) reported an average He of 0.60 and average of 6.3 alleles per locus with six SSRs and 72 fig cultivars.…”

“…To overcome this limitation, molecular marker based analysis have been carried out using isoenzyme markers (Cabrita et al, 2001); RAPDs (Khadari et al, 1995;Dalkilic et al, 2011); AFLPs (Baraket et al, 2009); ISSR (Guasmi et al, 2006;Ikegami et al, 2009). Microsattelites or SSRs have become the choice of marker due to their high polymorphism, co-dominance and reproducibility in recent genetic diversity studies for fig cultivars (Khadari et al, 2001;2004;Giraldo et al, 2005;Achtak et al, 2009;Çalışkan et al, 2012;Perez-Jiménez et al, 2012;Ganopoulos et al, 2015;Ferrara et al, 2016) However, genetic characterization of caprifig germplasms using molecular markers such as SSR and RAPD is limited to few studies (Dalkilic et al, 2011;Essid et al, 2015). Thus, the purpose of this study was to investigate genetic relationship between 45 caprifig genotypes and 2 common Turkish female fig cultivars with SSR markers.…”

Germplasm Resources and Strategy for Genetic Breeding of Lycium Species: A Review

“…To date, simple sequence repeat (SSR), conserved ortholog set II (COSII), characterized amplified region (SCAR), amplified fragment length polymorphism (AFLP), restriction site−associated DNA sequencing (RADseq), internal transcribed spacer (ITS), sequence-related amplified polymorphism (SRAP), intersimple sequence repeat (ISSR), and random amplified, microsatellite polymorphism (RAMP)-PCR markers have been applied in genetic diversity, population structure, morphological variation, phylogenetic inference, traceability, and cultivar/species identification and discrimination (Zhang et al, 2001(Zhang et al, , 2018Yin et al, 2005;Sze et al, 2008;Chung et al, 2009;Kwon et al, 2009;Levin et al, 2009;Zhao et al, 2010;Balasubramani et al, 2011;Liu et al, 2012Liu et al, , 2020bTripathi, 2013;Xin et al, 2013;Chen and Zhong, 2014;Wang et al, 2015a;Chen J. et al, 2017;McCulloch et al, 2020;Jung et al, 2021). SSR markers can be used for the detection of genetic polymorphisms of species, calculation of genetic relationships (genetic distance) between varieties, identification of cultivars, and even construction of genetic maps and QTL mapping with sufficient SSR markers Essid et al, 2015;Ibrahim et al, 2016;Thammina et al, 2017;Portis et al, 2018b). One hundred fifteen SSR and 12 ILP markers were applied to construct a genetic map with the F1 population (Hu, 2015).…”