Identification And Appraisal Of Phalaenopsis Germplasm Resources

Phalaenopsis aphrodita HG. Reichenbach is a kind of Orchidaceae Phalaenopsis Blume plant which is the most popular orchid variety in the word nowadays. In this study,we identificated the current Phalaenopsis germplasm, find out their genetic diversity and relationship, and provided reference for the future breeding. In this study, the relationship of Phalaenopsis germplasm resources were analyzed on the basis of morphological characters and SRAP marker. The results are as follows:1.49 characters of 58 Phalaenopsis resources were observed or measured according to the criteria of morphological characters. The results indicated there was big difference in quantitative characters and the genetic diversities of Phalaenopsis in the germplasm resource bank were abounding. The cluster analysis was established on the base of observed or measured data which showed that when the genetic distance was 0.62, the 58 gerrnplasms were classificed into eight main groups.2. An optimized SRAP reaction system for Phalaenopsis genome was established by this experiment.25μL reaction system contained 2.0 mmol/L Mg2+, 1.0 U Taq DNA polymerase,40 ng template DNA,0.8 mmol/L upstream primer and downstream primer. The PCR reaction procedure for SRAP analysis was as the follow, the temperature profile used for PCR was 94℃for 5min,followed by 5 cycles of 94℃for 1min,35℃for 1min,72℃for 1min, then 35 cycles of 94℃for1min,50℃for 1min,72℃for 1 min,and was terminated with a 7min DNA extension step at 72℃.3.30 pairs of polymorphic primer was selected from 100 pairs of SRAP primer, which were polymorphic among the 58 Phalaenopsis resources germplasms,465 polymorphism bands were obtained, the primer pairs amplified 8 to 20 bands and was 15.5 bands per primer pairs on average,406 polymorphism bands were obtained.the polymorphism ratio of primers was 87.31%,13.53% polymorphism bands were obtained per primer pairs on average.4. The cluster results indicated that when the genetic distance was 0.86, the 58 germplasms were classificed into six main groups. Number 16 and 34 cultivars which had genetic relationship with number 1 and 2 were classified into the same group. The cluster result was consistent with the pedigree of these varieties.