| After random sampling 40 wild Japanese quails and 62 wild Common quails fromwhich migrated to and settled down Weishan Lake region and Anyang district, Henan Province respectively, and 40 domestic quails from quail breeding farm in Yangzhou City, Jiangsu Province, different expressive levels of genetic markers of three quail species, i.e. 11 morphological markers, 10 blood protein polymorphism ( Isoenzyme) markers and 9 microsatellite DNA markers were detected. Based on cross fertility between wild Japanese quail and domestic quail and with collection of research data of international peers, the level of evolutionary divergence and population genetic differentiation between different kinds of domestic quail and wild quail species were studied by using fuzzy cluster, classical cluster, and genetic approach degree etc. Moreover, genetic coadaptability originated from population development and evolution history was given much more prominence to analyze by improving test method of population genetic disequilibrium and establishing statistic model of genetic coadaptability . The conclusions show as follows,1. Two wild quail species differ from domestic quail in body size, morphology, ecological habits and reproducing season. But some characters of domestic quail are still somewhat wild, furthermore, domestic quail has less difference from wild Japanese quail than from wild Common quail and it share lots of morphological characters withwild Japanese quail up to now.2. After a period of adaptation, domestic quail and wild Japanese quail can succeed in crossing in the artificial conditions. However, crossing fertility between them was lower than that of mating in and in, and fertilized egg of reciprocal crossing can be incubated and produced F1 without prezygotic isolation. Among all combinations of reciprocal crossing, crossing of wild male quail X female small-type domestic quail are proved to produce the best effect.3. After applying the method of classical and fuzzy cluster with 11 morphological markers, the results show that wild Japanese quail has a closed kinship with domestic quail than wild Common quail according to genetic distance and the level of evolutionary divergence and genetic differentiation.4. Results of 20 allele frequencies distributed in ten structure gene loci encoding enzyme types of muscles and organs and conclusions of t test of population heterozygosity, classical and fuzzy cluster indicate that two wild quail species in China have closer phylogenetic relationship with kinds of domestic quail around the world than wild species across Japanese islands. Furthermore, wild quail across Japanese islands is much more near to wild Japanese quail than to wild Common quail in China in the kinship.5. Results of genetic variation in 9 microsatellite DNA sites of three quail populations also show that the level of genetic differentiation of wild Japanese quail is lower with domestic quail than with wild Common quail, and all genetic mutations detected in domestic quail population can be found in wild Japanese quail in China. However, wild Common quail possesses of more variations and rich genetic diversity. The same conclusion in the kinship between domestic and two wild quail species as the above can be drawn from analysis of t test of population heterozygosity, classical and fuzzy clusters and genetic approach degree.6. Based on the data of different genetic markers, i.e. 11 morphological markers,10 blood protein polymorphism and 9 microsatellite DNA markers, this study proves the thesis about domestic quail originates from wild Japanese quail in different expressive levels of gene, and possibly derives from wild Japanese quail in China to a great extent.7. In light of comparing different test methods of linkage disequilibrium, genetic coadaptability of biochemistry degree was evaluated through corresponding statistic model in three quail populations. There do exist the effects of genetic coadaptability that play a role of maintaining population genetic equilibrium... |
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