| The present studies are to map the geographical distribution of allozymic alleles of Chinese rice landraces, to determine the genetic similarity by comparing with morphological traits, allozymes alleles and SSR markers, and to assess regeneration methods for rice germplasm using SSR markers. The results are as follows:1. There exist 53 alleles of 5 allozymes (Pgi, Amp, Sdh, Adh and Esf) in 5595 accession samples of Chinese rice landrace (Oryza sativa L), which account for 98.1% of 54 alleles having been reported in worldwide cultivated rice. It reveals the richness of genetic diversity of Chinese rice germplasm.2. The 53 alleles could be grouped into 4 kinds based on their distributions and frequencies. It is recommended that those landraces with one of 3 alleles (Amp32, Adhl2 and Esft1) being of the restricted-common kind and one of 11 alleles (Ampl4, Amp16, Amp23, Amp3?Amp33, Amp42, Amp4\ Sdhl3, Adhl0,Adhl3and Est5? being of the widespread-rare kind, should be prior monitored and conserved in core collection of rice. Ampl3 being of the widespread-rare kind was found only in indica rice.3. It was found that the rich allele diversity was existed in Henan, Hainan, Hubei, Hunan and Yunnan Provinces based on the distribution of allele frequency more than 0.01. It was found that the number and frequency of the tested alleles in Henan, Hubei, Hunan Provinces were more similar than that in other provinces. It is an evidence to support the hypothesis that Chinese cultivated rice was originated from the region of the middle Yangtze River-upper Hui River. The significant difference in number and frequency of the alleles between indica and japonica rice revealed the possibility originated independently for indica andjaponica rice.854. It was considered that the primitive cultivated rice (Oryza sativa L.) hi China was disseminated from its originated region of Henan-Hubei-Hunan. The rice hi Yunan-Guizhou Plateau was spread directly from Hunan through Sichuan Province. The rice in South China including Guangdong, Guangxi and Hainan Provinces was come from Hunan Province, with a strange influence from the gene flow of Southesat Asia countries. The rice hi Fujian Province was derived from Jiangxi Province, and then spread to Taiwan region. Rice hi Zhejiang, Shanghai, and Jiangsu Provinces was streamed mainly from its origin region through Anhui, Jiangxi Province. The primitive rice was disseminated to the north region of Shandong, Shanxi, Beijing and Tianjin Provinces, then to Northeast China through mainly Hebei and Henan Provinces.lt was found that the rice hi Liaonin Province was effected by the rice in East China. Through Shaanxi and Sichuang Provinces, primitive rice was introduced to Northwest China. It was noticed that some alleles were existed only in Sichuan Province, showing the unique position of Sichuan in rice domestication.5. The rice genetic similarity assessed by morphological traits, allozymes and SSR markers showed that allozyme markers could be applied in detecting the genetic variance hi collections with greater variation. However, the correlation between morphological traits and allozyme alleles was lower. Appropriated morphological traits combined with SSR markers could be effective for assessing the genetic diversity because the correlation of genetic distance between morphological traits and SSR markers was highly significant O=0.494**, /?=0.002) .6. Alleles with 5% frequency could be maintained in all regeneration population (25-300 individuals) based on the result detected by SSR markers hi 12 regeneration sizes using 2 harvest methods. The frequency of allele with initial 5% frequency was increased hi the population of 4* regeneration. Thus 150 individuals or/and equal panicles from per individual could be recommended for regeneration.7. hi present study, the large samples of Chinese rice landraces were analyzed by 12 locus in 5 allozymes. Mapping for allele geographical distribution and tracing rice origin and its dissemination hi China were also carrie...
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