Abstract:
Objective Based on SSR markers, the genetic diversity of passion fruit varieties in Fujian province were analyzed, and SSR fingerprints of passion fruit varieties were constructed.
Method The SSR markers of passion fruit were developed using transcriptome sequencing. 15 SSR markers with good repeatability and high polymorphism were screened for the identification and genetic polymorphism analysis of 17 Fujian passion fruit varieties, and the SSR molecular fingerprint was constructed.
Result Using the MISA software, 24319 unigenes above 1 kilo base pairs of passion fruit were analyzed, and a total of 11385 SSRs were identified from 8742 unigenes, with an appearing frequency of 46.82 % and an average distribution distance of 7.15 kb. Mononucleotide, dinucleotide and trinucleotide accounted for 63.72 %, 20.40 % and 14.28 % of the total SSR, respectively. Furthermore, the A/T、 AG/CT and AAG/CTT were the predominant dinucleotide repeat types for mononucleotide, dinucleotide and trinucleotide repeat types, respectively. There were 28257 SSR primers designed using Primer 3.0. 15 pairs of primers with good repeatability were selected from 26 pairs of effective primers to verify the polymorphism of 17 passion fruit cultivars. A total of 235 polymorphic bands were generated by 15 pairs of SSR primers, and the average PIC was 0.95. The 17 cultivars were divided into 7 groups at the genetic distance of 0.765 by UPGMA cluster analysis. According to the 15 pairs of polymorphic primer amplification electrophoresis map, PFSSR20 and PFSSR29 primer combinations were selected to construct DNA fingerprinting, and 17 passion fruit varieties could be identified.
Conclusion The SSR molecular markers constructed using passion fruit transcriptome data have high polymorphism potential and rich types. 17 Passiflora varieties (lines) were successfully identified based on the DNA fingerprints constructed in this study.