Study On Eevaluation Of Turf Quality And SSR Genetic Diversity Of Zoysia Japonica

Zoysia japonica is utilized extensively as warm-season turfgrass in the transitional and warm climatic regions of China at present because they provide excellent turf, and can be maintained with minimal cost. But its disadvantages limited its further application, the main limited factors are short green period and slow establishment. To breed new Zoysia japonica cultivars with longer green period and Rapid establishment is our aim. So the author studied on seedling vigor of 4 experimental materials of Zoysia japonica, gave turf quality evaluation of 4 materials established by seed according NTEP criterion, as well as the denetic diversity of 7 Zoysia japonica populations including 4 four material and their 3 hybrids by using SSR molecular marker. The results indicated that:1. In the green house seedling vigor experiment, 2 groups of Zoysia japonica seeds treated with NaOH soaking and removed its glume respectively, compared with untreated, two treated groups had higher FEP,MET,E50,and the difference were significant. The author recommended that in actual practice using NaOH soaking method to break Zoysia japonica seeds dormancy.2. H1 is the highest and the most numbers of leaves and tillers than other 3 materials, H1 showed the best seedling vigor. According its characteristics, we could judge that H1 is the new material with strong seedling vigor through breeding.3. The author studied on establishment of Zoysia japonica turf by seed in the Beijing area. 4 Zoysia japonica materials had much more increase in density and coverage within 60 days after seeding, 60 days later, the increased speed slowed down, this is the result of temperature and competition worked together. So suggested that the late spring to early summer seeding are preferred for establishing Zoysia japonica by seed in Beijing area. This allows the longest period of warm soil temperatures necessary for adequate establishment of Zoysia japonica, so in winter it had better freezing tolerance.4. H1 always had best turf quality during the observation time, owing to its high density, fine texture, strong freezing tolerance, as well as highest seedling vigor. H2 and Y2 had better turf quality than Y1. In addition, H1 showed the characters of short leaves and low height, H2 showed strongest aggression ability in morphic observation.5. Genetic diversity of 7 populations including 4 populations and 3 populations of their hybrids of Zoysia japonica were analyzed by means of SSRs technology.10 primer combinations with higher polymorphism were selected from 26 ones for the construction of fingerprint and the result showed that zoysia jopania had very high polymorphism.6. 10 primer combinations had detected 53 alleles averaged 5.3 alleles. Estimated polymorphism information content (PIC) for the 10 SSRs averaged 7.5 with a range from 0.61-0.82, the result indicated these primers had strong ability to detect genetic diversity of zoysia jopania, general genetic information was got.7. 19.62% of genetic variation came from inter-ppulation and the other 80.38% from within populations. It showed that most genetic variation came from within populations.8. Based on genetic distance ranged from 0.0303(H1,H2) to 0.1906(H1,Y1),the cluster analysis was made. The results showed the tendency that populations living in similar ecological conditions and with close geographical distance clustered firstly; the 3 hybrids population(H1 participate every hybrid ) can clustered to one group. It proved that SSR is a credible molecular maker. The information that H1 and Y1 has farther distance was gained, so in the further study we should cross-fertilize H1 and Y1 to get excellent hybrids.9. The annealing temperature of PCR amplification with 1℃decrement per cycle had better results than fixed annealing temperature, in addition, the effect of acrylamide gel containing urea is better than without urea because of the latter has more false band.