Genetic Diversity and Relationships in Local Varieties of Eggplant from Different Cultivar Groups as Assessed by Genomic SSR Markers

Abstract

Spain is a secondary center of diversity for eggplant (Solanum melongena). Spanish landraces of eggplant are normally classified in four cultivar groups: Round, Listada de Gandía, Semi-Long, and Long. We have used 19 genomic SSRs for the molecular characterization of 30 eggplant accessions corresponding to the four cultivar groups. Sixteen SSRs of which 15 were polymorphic could be amplified and 65 polymorphic alleles, with a range of two to 11 alleles/locus, were detected. The polymorphism information content (PIC) of SSR markers ranged from 0.07 to 0.77, with an average value of PIC=0.50. The mean observed heterozygosity (Ho) presented a very low value Ho=0.01, while the mean expected heterozygosity (He) had a value of He=0.57. Multivariate cluster analyses revealed that a considerable diversity exists within each of the cultivar groups. Listada de Gandía and Long cultivar groups were clearly separated from each other in different branches of phenogram. The principal coordinates analysis (PCoA) confirmed that each of the cultivar groups is genetically diverse and, with the exception of the Round group, they plot in different areas of the PCoA graph. Overall, the results indicate that Spanish eggplant landraces present a high degree of homozygosis, considerable intra-cultivar group diversity, and a certain degree of genetic differentiation. This information is of interest for selection and breeding of eggplant as well as for germplasm conservation.

Multi-Level Characterization of Eggplant Accessions from Greek Islands and the Mainland Contributes to the Enhancement and Conservation of this Germplasm and Reveals a Large Diversity and Signatures of Differentiation between both Origins

“…In addition, the number of alleles/locus in the whole collection was high (4.6), higher than that (3.67) revealed by Augustinos et al [23], when they studied a limited number of Greek traditional eggplant cultivars. Taking into consideration other studies on eggplants from different geographic origin or different cultivar types based on SSR data, the number of alleles/locus calculated in our eggplant collection is lower than that detected by Hurtado et al [35] and Liu et al [36], but almost similar to those by Demir et al [74], Muñoz-Falcón et al [73], Tümbilen et al [66], and Vilanova et al [50,75]. Two of the SSR markers used in our study (csm27, csm32), have also been used by Hurtado et al [35] and Vilanova et al [50].…”

“…Low H o was also detected by Augustinos et al [23] and Liu et al [36] (0.04 and 0.03, respectively) and Vilanova et al [50,75]. The high level of homozygosity in eggplant landraces shows that pure lines can easily be derived by individual selection from these materials [75]. Although genetic diversity based on molecular data is dependent on the type and number of markers used and the accessions tested [66], the relatively high PIC values and average number of alleles/locus detected and also the high levels of heterozygosity observed compared to other similar studies, indicate that considerable diversity exists in our eggplant collection.…”

“…Muñoz-Falcón et al [77] detected significantly lower values for Spanish landraces (0.02) and for non-Spanish landraces (0.02), whereas Cericola et al [34] also found that most eggplant landraces used in their study had low heterozygosity values, and only 38 out of 238 materials had H o > 0.10. Low H o was also detected by Augustinos et al [23] and Liu et al [36] (0.04 and 0.03, respectively) and Vilanova et al [50,75]. The high level of homozygosity in eggplant landraces shows that pure lines can easily be derived by individual selection from these materials [75].…”

Molecular characterization of some brinjal genotypes (Solanum melongena L) using simple sequence repeat (SSR) markers

“…Using 4 SSR markers, a total of 44 alleles were detected among the 48 brinjal genotypes. The average number of allele per locus was 11, with a range of 9 (smSSR03) to as many as 14 (smSSR01) which is supported by Vilanova et al (2014), they found 2 to 11 alleles/locus by using 19 genomic SSRs for the molecular characterization of 30 eggplant accessions; the number of alleles ranged from 2 to 8 with a mean of 4.3 alleles per marker recorded by Caguiat and Hautea (2014), Adeniji et al (2012) observed a total of 417 alleles amplified with the number of alleles ranging from 5 (EM 141) to 38 (EM 120 b), Verma et al (2012) recorded the number of alleles per primer ranging from 2 to 10, with a mean of 4.67; Sunseri et al (2010) found the number of alleles ranging from 2 to 7 with an average of 4.5. Nearly similar observation was found by Li et al (2003) where they ranged from 2 alleles to 11 alleles with an average of 6.61 alleles per locus in chilli.…”

“…As a measure of the informativeness of microsatellites, the PIC value ranges from a low of 0.6413 (smSSR14) to a high of 0.8536 (smSSR11) and averaged 0.7660 (Table 3). The results of the study supported by Vilanova et al (2014), recorded the polymorphism information content (PIC) of SSR markers ranging from 0.07 to 0.77, with an average value of PIC=0.50. Also SSRs was selected by Caguiat and Hautea (2014) based on their high polymorphism information content (PIC) and the high quality of bands.…”