## 3 Results  
### Genetic Variation of Apricots from Control Database  
All eleven microsatellite markers were highly polymorphic in the 53 apricot control cultivars (Table 3, Table S2). Ten to sixteen alleles were detected at individual microsatellite loci, with an average of 13 alleles per locus. The lowest number of alleles (10) were detected at the UDP98-411, Pchgma2, and Pchgms4 loci, but the UDP96-019 locus showed the lowest polymorphism detection rate. At this locus, with 13 alleles detected, only 2.547 alleles were classified as effective. This is due to the fact that the 165 bp allele occurred with a frequency of 61%. In contrast, the other alleles had frequencies ranging from 1% to 10% (Figure S1). At this least polymorphic locus (UDP96-019), there was a 17% probability of not distinguishing the genotypes from our set (PI = 0.170 in Table 3). On the other hand, the locus with the highest polymorphic ability (UDP97-402) had two alleles fewer than the locus with the lowest polymorphism detection rate, namely, 11. However, their distribution among cultivars was comparable, and up to 8.5 alleles of the 11 detected were effective (Table 3). The most common allele of 120 bp occurred with a frequency of 18%, and the least common allele of 128 bp with 2%, while the average frequency was 9% (Figure S1). The probability of identity of the genotypes at this locus decreased to 0.025. This represents only \begin{table}
\begin{tabular}{l c c c c} \hline \hline  & & & \multicolumn{2}{c}{**PCR Conditions**} \\
**Locus** & **Reference** & **Repetition** & \
\begin{tabular}{c} **Mg\({}^{2+}\)** \\ **Concentration** \\ \end{tabular} &
\begin{tabular}{c} **Annealing** \\ **Temperature** \\ \end{tabular} \\ \hline UDP96-005 & [10] & (AC)\({}_{\text{n}}\)TG(CT)\({}_{\text{m}}\)CA(CT)\({}_{\text{k}}\) & 1.5 mM & 58 \({}^{\circ}\)C \\ UDP98-409 & [10] & (AG)\({}_{\text{n}}\) & 1.5 mM & 57 \({}^{\circ}\)C \\ Pchcm55 & [19] & (CA)\({}_{\text{n}}\)(TA)\({}_{\text{m}}\) & 2 mM & 57 \({}^{\circ}\)C \\ UDP98-412 & [20] & (AG)\({}_{\text{n}}\) & 1.5 mM & 57 \({}^{\circ}\)C \\ UDP98-411 & [20] & (TC)\({}_{\text{n}}\) & 1.5 mM & 57 \({}^{\circ}\)C \\ Pchgms2 & [19] & (CT)\({}_{\text{n}}\) & 1.5 mM & 57 \({}^{\circ}\)C \\ UDP98-406 & [10] & (AG)\({}_{\text{n}}\) & 2.5 mM & 57 \({}^{\circ}\)C \\ UDP96-003 & [10] & (CT)\({}_{\text{n}}\)(CA)\({}_{\text{m}}\) & 1.5 mM & 57 \({}^{\circ}\)C \\ Pchgms4 & [19] & (CT)\({}_{\text{n}}\) & 2.5 mM & 57 \({}^{\circ}\)C \\ UDP96-019 & [10] & (TG)\({}_{\text{n}}\)(AC)\({}_{\text{m}}\) & 2.5 mM & 57 \({}^{\circ}\)C \\ UDP97-402 & [10] & (AG)\({}_{\text{n}}\) & 1.5 mM & 58 \({}^{\circ}\)C \\ \hline \hline \end{tabular}
\end{table} 
Table 2: List of microsatellite markers used for apricot genetic variation study. a 2.5% probability of not distinguishing the genotypes when using only this microsatellite marker. The PIC values were in the range 0.592-0.871, with an average of 0.794. Allelic patterns across geographical origin groups according to Table 1 revealed that the most diverse alleles were detected in the Central Europe and West Europe groups. On the other hand, these groups showed the lowest expected heterozygosity considering the lower number of samples in the Central Asia and China group (Figure 2A). After subdividing the Central Europe group into old local cultivars and modern cultivars resulting from the hybridization of old cultivars with cultivars from China and Central Asia, low _He_ values were found for the old cultivars group and much higher _He_ values for the modern cultivar group (Figure 2B). The highest number of unique alleles in a single population within a geographical origin was 1.455 in the Central European group, and, again, it was caused by the high number of unique alleles in the modern cultivar group. The genetic variation of 53 apricot cultivars was also evaluated using Structure analysis (Figure 3).