| The seeds of nineteen black locust provenances from different regions in China were collected. The germination properties of seeds of the 19 provenances were measured. The plant populations from all 19 black locust provenances were established under different growth conditions, with locations at Baoding city, Shahe of Xingtai and Gaoyi of Shijiazhuang, Hebei Province. The genetic structure and genetic diversity of all tested provenances were studied by using the phenotypic traits, biochemical markers and DNA markers. The experimental results were as follows:1. The seed traits including per 1000-grain weight, germination potential, germination index, α-amylase activity, β-amylase activity of tested 19 provenances were analyzed. There were significant differences among the tested provenances on above traits. Because the harvest date and storage period of the seeds were not the same, it is not clear whether genetic background or environmental factors caused the differences.2. (1) At the 3 experimental locations, the plant height and basal diameter of plant had most significant differences between Xingtai and Shijiazhuang. It was also found that a significant difference existed between Baoding and the other two locations. (2) At the population level, the differences at plant height trait among three locations reached the significant level. The difference at basal diameter trait between Xingtai and Shijiazhuang was not significant, but there were significant differences at this trait between above two locations and Baoding. These results indicated that the environmental factors had important effects on plant growth. There existed an obvious interaction between the environmental factor and genetic factor based on the result analysis by combined variance method. All above results showed environmental factor having effects on phenotype largely controlled by genetic factors. (3) There were no obvious correlations between the growth traits of tested provenances and the local climate factors at all experimental locations. From the experiment at seedling stage, it is found that the provenance from Zhuhua, Hebei (No. 11) grew better at all three locations. (4) In the cluster analysis for the phenotypic traits from all three locations, no stable tendencies for all tested phenotypic traits were found. Therefore, the phenotypic traits from the tested provenances could only preliminarily reflect the differences in different provenances.3. Using PAGE and SGE electrophoresis techniques, the polymorphisms of Amy, Fe, Lap, Idh, Mdh, 6Pgd and Skd, in total seven allozymes, were analyzed, by which the genetic structure and genetic diversity of the 19 provenances of black locust were elucidated at the biochemical level. The results were as follows: (1) There were in total 14 sites for all assayed allozymes, and 12 of them were polymorphism including 40 alleles. (2) In total populations consisting of above 7 allozymes, the average number of allele (A) and the average number of effictive allele (Ae) was 2.9500 and 2.2053, respectively. The mean expected heterozygosity (He), the mean observed heterozygosity (Ho) and the mean fixation (F) were 0.5305, 0.4065 and 0.0086, respectively. (3) The values of A and Ae changed from 2.73 to 3.18 and from 1.95 to 2.40. The values of Ho and He changed from 0.3892 to 0.5568 and from 0.4732 and 0.5661. The average of gene differentiation coefficient (Gst) among the tested provenances was 0.0381. The genetic distances changed from 0.085 to 0.212. A cluster analysis was carried out based on the average genetic distances. Five groups could be divided for the tested provenances at the position of 0.14, the value of average of genetic distances. The results from cluster analysis were accordance to the meteorological sources of the provenances at high degree. The tested provenances of black locust can be classified into three groups, including Northwestern region, Northeastern and Huabei region, and Huanan and Southern region. But the differences of genetic distances among above different regions were not significant. It is found that there existed a overlapping at the trait of genetic distance between different regions, indicating that the meteorological model has not been established based on allozyme analysis. (4) The total results from allozyme analysis at the present study indicated that the population genetic structure of provenances of black locust is complicate with more genetic diversity. There have no obvious correlations between the genetic parameters and the local climatic factors.4. In total six microsatellite markers including Rops02, Rops04, Rops05> Rops06^ Rops08 and RopslO were selected to PCR amplify the polymorphisms, by which to elucidate the genetic structure and genetic diversity of black locust at the DNA level. (1) 6, 3, 6, 5,5 and 4 alleles were PCR amplified by using above primer pairs and found in all 19 tested provenances. (2) Based on the analysis of whole population, the average of allele number (A) was 4.8333. The average of effective allele (Ae) was 2.8580. The mean expected heterozygosity (Hz) was 0.6285. The mean observed heterozygosity (Ho) was 0.6479. The mean fixation index (F) was 0.0001. (3) The Ae, Ho and He changed from 2.6598 to 3.0024, from 0.5990 to 0.6719 and from 0.6046 to 0.6493, respectively. The average of gene differentiation coefficient (Gst) was 0.0128. The genetic distances among the tested provenances changed from 0.017 to 0.137. A cluster analysis was carried out based on the average of genetic distances. Five groups could be divided for the tested provenances at the position of 0.07, the value of average of genetic distances. The results from cluster analysis were accordance to the meteorological source of the provenance at high degree. The tested provenances of black locust can also be classified into three groups, including Northwestern region, Northeastern and Huabei region, and Huanan and Southern region. But thedifferences of genetic distances among above different regions were not significant. It is found that there existed a overlapping at the trait of genetic distance between different regions, indicating that the meteorological model has not been established based on SSR analysis. (4) Similar to the results from allozyme analysis, the total results from SSR analysis at the present study indicated that the population genetic structure of provenances of black locust is complicate with more genetic diversity. In the correlation analysis between genetic parameters and local climatic factors, there have positive correlations between Ae, He and Ho and annual average temperature with coefficient 0.7349,0.6609 and 0.7610, respectively.5. The correlations between phenotypic traits, allozyme makers and SSR markers were carried out. The results indicated that the coefficient (r=O.O198) between phenotypic traits and allozyme markers was low and did not reached the significant level, so was the coefficient(r= -0.0249) between phenotypic traits and SSR markers. The coefficient^ 0.8960**) between SSR markers and allozyme markers was high and reached the most significant level.
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