Читать книгу Biotechnology of Fruit and Nut Crops - Группа авторов - Страница 73

Marker-assisted selection (MAS) has not been utilized for pistachio breeding. There is only one linkage map for pistachio; it was constructed using a cross between pistachio and monoecious P. atlantica (Turkeli and Kafkas, 2013). Bulk segregant analysis was used to determine an RAPD marker linked to sex determination (Hormaza et al., 1994). An RAPD marker (OPO08₉₄₅) with a 945 bp amplification band was present only in the bulked female samples and absent in the bulked male samples of the two female parents pollinated by a common male parent among 700 screened RAPD markers. However, this marker was ineffective for sex determination in other Pistacia spp. (Hormaza et al., 1994). Kafkas et al. (2001) used 472 RAPD markers to determine sex determination in P. eurycarpa and P. atlantica. Two markers linked to sex determination in P. eurycarpa and one in P. atlantica were found. OPO08₉₄₅ RAPD marker was also converted to a sequenced characterized amplified region (SCAR) marker by Yakubov et al. (2005) but was ineffective. A SCAR primer that amplified a 297 bp PCR product and with a touchdown PCR programme together with SCAR primers showed potential as a female-specific marker. This SCAR primer pair was effective for sex determination of four P. atlantica and four P. khinjuk individuals (Esfandiyari et al., 2012); however, another study reported that these RAPD and SCAR primers provided false negatives in some female and false positives in some male pistachio individuals (‘Siirt’ × ‘Bağyolu’) F1 segregating populations. It was also reported that the SCAR marker could not distinguish sex in wild Pistacia species, and, therefore, restriction site associated DNA sequencing (RAD sequencing) was utilized (Kafkas et al., 2015). Eight single nucleotide polymorphism (SNP) loci distinguished sex type with 100% accuracy. Four SNPs could separate sex type according to High Resolution Melting (HRM) analysis. Due to the female heterogamy in all candidate SNP loci, they also reported that pistachio has a ZZ/ZW sex determination system. This sex determination is compatible with karyotype analysis using Fluorescent In Situ Hybridization (FISH) with probes for 5S and 45S rDNAs, and the pistachio specific satellite DNAs PIVE-40, and PIVE-180, together with DAPI-staining (Sola-Campoy et al., 2015). Proteomics has also been used for sex determination in P. chinensis (Xiong et al., 2013). As male and female plants maintain their respective sexual phenotypes (Ma et al., 2012) and a 1:1 sex ratio (Yu and Lu, 2011) is found in P. chinensis and other Pistacia species, it is expected that sex difference in this species should display at the proteome level.