| As an important component of biodiversity, genetic diversity is expressed at various levels, and should be studied at various levels too. In this study fourteen wild Lespedeza germplasms were collected from Beijing, Shanxi and Heilongjiang province in 2001 and 2002, and a nursary of these germplasms was established. Genetic diversity of the Lespedeza populations were studied at morphological . allozyme and RAPD levels. Seventeen important morphological characters were analysed to identify and evaluate genetic diversity of morphology of the Lespedeza populations. Fourteen vital morphological characters were studied using basic statistics, correlation analysis, factor analysis and cluster analysis. Zymograms were analysed using eighteen alleles of seven allozymes. Sixty 10-Oligonucleotide primers were used in RAPD anylysis. The main results as follows:1. Mean, variance, standard deviation, coefficient of variation of fourteen vital morphological characters indicated that great diversity existed either among species or among populations, with CV ranging from 28.89-122.36%(except DTM,which has a CV of 4.72%).Correlation analysis indicated that IL showed a significant positive correlations with PFK LL and LW (p<0.05) , but a negative correlation with NM(p<0.05). There were also strong positive correlations between each other of LL, LW, LA and SW. A significant positive correlations were also detected between DMY and SY (p<0.01), GH and BN (p<0.05). However there were negative correlations between GC and SW(p<0.05), DTM and GH(p<0.05).Factor analysis indicated that the first five principal components accounted for 91.472% of the total variation, therefore could summarize most of the variation. Three factors could summarize majority variation, which were named as morphological factor, yield factor and growth factor respectively.Cluster analysis based on Euclidean distance of morphological characters confirmed the traditional taxonomy system.2. With an improved Tris-HCl complicated extraction buffer (2-mercaptothanol,0.1% v/v; EDTA , tetrasodium salt, 0.001mol/L; KC12, 0.01mol/L; MgCl2 . 6H2O, 0.01mol/L; polyvinylpyrrolidone, PVP 40 000,20% w/v; Tris-HCl buffer,pH7.5,0.1mol/L),7 enzymes (PER,PPO,AAT,MDH,PGI,PGM,EST) were successfully employed in allozyme analysis.Through genetic analysis of 18 enzyme alleles abtained from 7 allozyme, high genetic variability was quantified by seven indices including percentage of polymorphic loci(P),mean number of alleles per locus(A),mean observed heterozygosity per locus(Ho) and expectedheterozygosity per locus (He), Shannon's information Index (7),ratios of gene diversities of heterozygosities (Fst) and gene flow(Nm) . The observed mean values of these indices of the 14 Lespedeza populations were 54.62%, 1.7437, 0.3845, 0.2598, 0.3782, 0.4476 and 0.3096, respectively.Results of allozyme cluster analysis based on Nei's (1972) genetic distance agreed with the results of morphological cluster analysis.3. With the improved CTAB protocol, high quality genome DNA of the Lespedeza populations were obtained for RAPD amplification. A optimal reaction system suitalble for the RAPD analysis in the Lespedeza populations was established(25uL total reaction buffer), composed by 75ng template DNA, 2.1 mM Mg2+, 200 uM dNTP, 0. 2 pm primer uL-1, 10 X buffer 2. 5uL, 1.5 U TaqDNA polymerase.Amplificative thermal reaction program suitable for the RAPD analysis in the Lespedeza populations was devised as followings: a initial denaturation 94℃ for 3 minutes; 45 cycles of 94℃ for 30 seconds, 36℃ for 30 seconds, 72℃ for 1 minutes; and a final extention at 72℃ for 10min.Sixty 10-oligonucleotide primers from Opron Inc. were used for polymorphic selection, with fifty four (90%) primers that produced polymorphic products. A total of 209 bands amplified from 20 primers were selected for RAPD analysis.The data derived from the 209 bands were used to generate Nei's (1972) genetic distance and to construct a dendrogram using UPGMA in POPGENE (Ve...
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