Development and characterization of polymorphic microsatellite markers for the sweet orange (Citrus sinensis L. Osbeck)

Abstract

The aims of this study were to develop simple sequence repeat markers (SSRs or microsatellite markers) in citrus and to evaluate the efficiency of these markers for characterization of sweet orange. We developed SSRs from a genomic library of 'Pêra IAC' sweet orange enriched for AG/TC, GT/CA, TCA/AGT and AAC/TTG sequence repeats. We selected 279 sequences from which 171 primer pairs were designed of which 113 with the best banding patterns were selected. Characterization of sweet orange microsatellite loci revealed that AG/TC was the most abundant (69%) microsatellite class isolated, followed by GT/CA (15.9%), TCA/AGT (8%) and AAC/TTG (6.2%). The number of alleles ranged from 1 to 4, with a mean of 2 alleles per locus. Four microsatellite loci developed in this study were found to be useful for sweet orange DNA typing. The data obtained from microsatellites loci considered polymorphic will be useful as tools in the selection of zygotic and nucellar plants, identification of seedlings etc. for the cultivars

Assessment of genetic diversity of Tunisian orange, Citrus sinensis (L.) Osbeck using microsatellite (SSR) markers

“…Moreover, several studies have shown that sweet orange varieties are monophyletic, resulting from a single ancestor through mutation and selection of desirable clones (Fang and Roose, 1997). The low genetic diversity among the orange cultivars suggests that the observed morphological polymorphism might be associated with somatic mutations, which were confirmed by the molecular markers (Novelli et al, 2006). In the present, it was possible to differentiate the two trees of Washington navel cultivar, WN1 and WN2 by SSR specific alleles.…”

Genetic Diversity in Citrus

“…Roose (1988), reported it was difficult to distinguish cultivars originated mutations using isozyme markers. Low level of polymorphism in orange also found with ISSR (Fang & Roose, 1997), SSR (Luro et al, 2000;Novelli et al, 2006), SRAP (Uzun et al, 2009a). On the other hand, no variation found in studied oranges in some researchs (Orford et al, 1995;Qing-Qin et al, 2007).…”

“…In the cultivated citrus, sweet orange (C. sinensis L. Osbeck) originated as a natural hybrid between mandarin and pummelo (Barrett & Rhodes, 1976), showed low level of genetic diversity according to lots of previous studies (Luro et al, 1995;Novelli et al, 2000;Novelli et al, 2006;Uzun, 2009). It is notified that most of sweet oranges obtained by mutation from one ancestor tree.…”

“…It is indicated despite the existence of substantial diversity among cultivated genotypes in respect of morphological, physiological and agronomic traits, very little DNA variation has been detected using DNAmarkers (Novelli et al, 2006). Same researcher found low level of genetic polymorphism among 41 orange cultivars.…”

Molecular characterization of sour orange (Citrus aurantium) accessions and their relatives using SSR and SRAP markers

“…Correspondingly, genetic diversity statistics have also been calculated for each individual SSR marker, the entire population, and specified Citrus groups (Barkley et al, 2006). The efficiency of these markers for the characterization of sweet orange has been tested and evaluated using SSR markers in citrus (Novelli et al, 2006). Four microsatellite loci have been suggested to be useful tools for DNA typing in sweet orange.…”