| Ceratoides belongs to Chenopodiaceae, which distributed extensively in Eurasia and mainly at arid and extra arid regions of the North Temperate Zone. This genera has 7 plant species all over the world, there are 4 plant species and 1 variation in China. This genera has great value of ecology and economy. Ceratoides in China owned the characteristics as later florescence, low setting percentage, shorter seed longevity and degeneration. On this account, we introduced Ceratoides lanata (Pursh) Powell of early florescence, high setting percentage. All these would provide academic base to breeding and crossbreed of new variety for the future. The paper chose different generations of C. lanata planting in China as the researching object, studied the regularity of genetic variation in biological characteristic, morphological, cytology, allozyme and DNA, revealed the characteristics and regularity of genetic variation after introduction, the main results were as follows:1. 4 generations of C. lanata were varying in phonological phases, floral dynamic, pollen viability, seed setting rate, germination rate, vigor index and germination index, while varied little in growth and nutrition. Variation trends of indexes above in different generations were: BM0 generation basically was the smallest, and then BM1, BM2 and BM3 generations were the biggest and which two were close.2. There was a larger variation of C. lanata phenotypic traits. Within generations, the variance coefficient of branch length, regenerated shoots, leaf length, leaf breadth, plant spread were all decreased while plant height, females flowers number in axil, branch diameter were all increased along with the increasing of generations. General potential analysis show that plant height, female flowers number in axil, leaf breadth, staminate flowers panicle length had higher genetic potential and were influenced mostly by genetic factor, while leaf length, branch diameter, plant spread had lower genetic potential and were influenced mostly by environmental factor; Correlation analysis about several phenotypic traits showed that between branch length and nodes number in female flowers, regenerated shoots, between nodes number in Female flowers and regenerated shoots were all influenced both by environmental and genetic factors, the relativity between leaf length and leaf breadth were influenced mostly by environmental factor, and relativities among other indexes were influenced mostly by genetic factor. Genetic gains analysis showed that under 5% choosing pressure, the genetic gains of staminate flowers panicle length, rege- nerated shoots, leaf breadth etc. were all higher. 3. The karyotype of 4 C. lanata generations were all belonged to 1A type which did not variance obviously, karyotype formula was 2n=2x=18=18m, and the coefficient of variation of chromosome length ratio and average arm ratio were 7.66% and 4.79%, respectively.4. The results of allozyme showed that percent of polymorphic loci of 4 generations of C. lanata all was 85.71%. Different generations of C. lanata all had a larger genetic diversity, and in which BM1 was the largest while BM3 was the least. Genetic variation of C. lanata derived from 4 generations populations. The farther of generations leaved the smaller of genetic identity, and the closer of generations leaved the larger of genetic identity.5. The orthogonal design was used to optimize ISSR amplification system of C. lanata in five factors (Taq DNA polymerase, dNTP, primer, Mg2+ and DNA templet) at four levels respectively. The best of reaction system of C. lanata was established, 20μl reaction system which contained 1×buffer, 1.5U Taq DNA polymerase, 0.2mmol/L dNTP, 0.5μmol/L primer, 2.5 mmol/L Mg2+ and 10ng template DNA.6. Results of ISSR-PCR genetic variance of C. lanata showed that 167 loci were detected in 16 ISSR primers, polymorphic loci percent was 89.22%,the gene heterogeneity of 4 generations was 0.2725~0.2306,shannon index was0.4441~0.3888,it showed that there was polymorphism in C. lanata. There was abundant diversity in C. lanata population, from BM0 to BM1, the diversity was increased and after BM1, it was gradually decreased. There was 83.49% genetic variance within generations and 16.51% among generations. Along with the increasing of generation, genetic differentiation among generations was decreasing; and the farther of generations leaved the larger of genetic differentiation coefficient. The results of clustering showed that BM2 and BM3 was the first cluster which with BM1 was the second cluster, and then with BM0 to be the third cluster.
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