Abstract:This study focus on the investigation of crop germplasm resources in coastal areas of Shandong Province, including 132 villages in 82 towns of 34 counties. The survey collected local varieties and wild resources of grain crops, economic crops, vegetables and fruit trees, with the total of 848 collected samples which belong to 54 species of 39 genera in 15 families. In this study, Local situation, growth and decline conditions of crop germplasm resources were analyzed. Besides, the botanical classification and utilization importance of crop germplasm resources were estimated. Furthermore, the conservation, development and utilization of crop germplasm resources in coastal areas of Shandong Province were also discussed in the paper.
Abstract:Soybean Kunitz trypsin inhibitor (SKTI) extensively exists in cultivated and wild soybeans with many kinds of variants, which is often used as a genetic marker to study the origin and dissemination of soybeans. In this study, 10131 Chinese soybean landrace accessions were identified for SKTI types and a set of representative sample of 187 soybean landraces was analyzed to assess the genetic diversity and relationships of different SKTI type accessions using 20 nuclear SSR markers and 5 chloroplast SSR markers. Results showed that at the nuclear DNA level, the genetic diversity of the Tib type accessions was lower than that of the Tia type, but the genetic diversity at the chloroplast DNA level was just opposite; The cluster analysis showed that the Tib accessions from different regions tended to cluster together preferentially, indicating a close relationship among those Tib accessions. The Tib type soybean landraces in Gansu Province were rich in diversity of chloroplast haplotypes, and were principally comprised of type Ⅱ and Ⅲ. The soybean landraces with chloroplast haplotype Ⅱ in Gansu might be the main source of the soybeans with the same type in other provinces. Based on that Tib type soybean landraces in Gansu Province had a higher genetic diversity and a close relationship with those from other provinces, Gansu Province might be a center of the origin for Tib type soybeans in China.
Abstract:Thermo-tolerance of 95 accessions of javanica rice, which originated from different countries and regions, was determined by high temperature stress in phytron and interval sowing in field. According to the comprehensive seed set, the 95 accessions of javanica rice were classified into 3 groups by thermo-tolerance based on clustering analysis. In consideration of comprehensive seed set and seed set of interval sowing in field, the variety of IRAT109 (IRRI accession number 38563), 260 (IRRI accession number 14888) and L 4-34 (IRRI accession number 13403) were of thermo-tolerance, which can be used for breeding new thermo-tolerant rice and genetic research of high temperature stress.
Abstract:Abstract: The resistance to bacterial blight of twenty-six rice varieties bred in recent years，were evaluated by inoculation with eleven Xanthomonas oryzae pv. oryzae (Xoo) strains at the tillering and the booting stages, respectively. The results indicated that the resistance level of most varieties was identical at the two growth stages. Among them, three varieties, including Xinhuangzhan, Hua 201S-1 and XF10450, exhibited high resistance to Xoo with broad spectrum, and their lesion lengths were shorter than 5cm. The other varieties showed different resistance level, four varieties, including Huanghuazhan, Hanyou113, Xinliangyou3411 and Tianyou 145 were resistance to four-five Xoo strains. Whileas, Hanyou 75, Hanyou 715 and 009067 were highly susceptible to fourteen tested strains.Tha other sixteen varieties were middlely susceptible or susceptible.
Abstract:In order to explore the genetic structure differences of natural populations of Pinus bungeana in geographical distributions. Genetic structure of 5 distribution regions was studied using 7 pairs of SSR primes. The result showed that: 14 polymorphic loci were detected in 476 individuals among five regions. The observed number of alleles（Na）, effective number of alleles (Ne), Shannon's information index (I), observed heterozygosity (Ho), expected heterozygosity (He) and Nei's expected heterozygosity (Nei's) were 1.7143~2.1429、1.1942~1.571、0.1948~0.4954、0.1726~0.3116、0.1178~0.3325、0.1172~0.3307 respectively. The genetic diversity was relatively low among regions but the difference was high. The regions with the highest genetic diversity were west side of the Qinling Mountain followed by the Daba Mountain; the Taihang and Lvliang Mountain were relatively low. Genetic differentiation coefficient (Fst) was between 0.0138 ~ 0.2242 and gene flow (Nm) was between 0.865 ~ 17.8646 among regions. The populations with high genetic differentiation and gene flow were west side of the Qinling Mountain and among the regions of west side of the Qinling Mountain and other regions. Genetic diversity center of Pinus Bungeana were mainly distributed in the west side of the Qinling and Daba Mountain, therefore, the protection of Pinus Bungeana shoud focus on these regions.
Abstract:Using SRAP markers with eight primer combinations, the genetic diversity was assessed within and among seven natural populations of wild rice species in Hainan,a total of 219 alleles were detected in 120 accessions of O. rufipogon, 55 accessions of O.meyeriana and 26 accessions of O. officinalis ,and the polymorphic loci were 74.89％ , 42.47％ and 25.11％ respectively. Values obtained for Shannon's information index (I) suggested that O. rufipogon were 0.3277 showed the highest genetic diversity ，O.meyeriana were 0.2204 and O.officinalis were 0.1113 showed the lowst diversity. .UPGMA cluster analysis showed that all individuals of each population formed a distinct cluster,, that according to the geographical origin, the individuals within each population of wild rice with no cross to others. Based on the coefficient of gene differentiation, the genetic diversity of O. rufipogon groups were 0.2135, and its mean gene diversity was higher within than among populations,suggest of genetic differentiation among O. rufipogon populations was not significant, means most of the genetic diversity was due to differences within populations. Based on the results in Nei′s genetic diversity and Shannon's Information index analysis, it was suggested that populations in WDL and WDA should be given conservation priority. In addition, in situ conservation should be carried out for both O. meyeriana and O. officinalis because of a moderate genetic differentiation among populations or a small population size.
Abstract:Paphiopedium micranthum is rare and endangered orchid known as slipper orchid. Its survival had been so seriously threaten that it lead to a drastic decline in number and range of wild population because of commercial need and habitation destruction In order to assess its influence on genetic structure of P. micranthum and provide fundamental information for its protection, 167 samples from seven populations under the different disturb circumstance in the over collection region were drawn to detect its genetic diversity and structure within and among populations by Sequence-related amplified polymorphism (SRAP) technology. Molecular marker revealed that it had a high level of genetic diversity at species level (PPB=81.25%; I=0.3709) despite small population sizes, a quiet low level at population (PPB=47.92%; I=0.2348), a moderate mean genetic distance among population (D = 0.1268). Analysis of molecular variance (AMOVA) indicated that the contribution (66.27%) of variability came within population level, which was consistence with the coefficient of genetic differentiation among populations (Gst=0.3568) result. P. micranthum maintained significantly higher population differentiation compared to other outcrossing orchid species. The current studies suggest that selective collection, habitats destroyed and fragmented lead to loss of genetic diversity within populations and aggravated gene differentiation In addition, a gene drift was very important reason responsible for a high gene differentiation adaptation evolution may be another reason for genetic differentiation. Genetic flow may be not the main factor for differentiation.
Abstract:The current article is a synthesis of progress in cryopreservation state and research of plant germplasm resources in the world, based on the Second Report of the State of the World’s Plant Genetic Resources for Food and Agriculture, International Conferences and other literatures. The contents covered material types, basic procedures, methods and techniques, theoretical basis, influence factors, costs, strategy and practical application in the cryopreservation of plant germplasm resources. It also identified the gaps and put forward striving direction and the suggestions for strengthening the safety and long-term cryopreservation of non-orthodox seed plant germplasm resources in China.
Abstract:Abstract: Eighteen SSR primer pairs were used to amplify SSR fragments for 96 strawberry cultivars. The 18 SSR primers generated a total of 184 bands among which 172 (93.5％) bands were found to be polymorphic. The number of polymorphic band amplified per primer pair ranged from 6 to 19, with a average of 9.56. The value of locus polymorphism information content (PIC) ranged from 0.5726 to 0.8885, and averaged 0.8057. The genetic similarity revealed by NTSYS and the clustering results of UPGMA showed that these 96 strawberry cultivars from different origins could not separately clustered well. There was no significant correlation between the genetic relationships and the origins of the cultivars. The cluster of Chinese landraces was relatively concentrated, while the genetic relationships between Chinese landraces and the developed cultivars in China were relatively farther. The genetic variations of the euramerican cultivars and Janpan cultivars were more obvious than those of the Chinese landraces and the developed cultivars in China. Key Words: Strawberry ; Genetic relationship; SSR
Abstract:To evaluate the heterosis of rice starch viscosity properties, 30 hybrid combinations were obtained from incomplete diallel cross between six sterile lines and five restorer lines of indica hybrid rice cultivars. The rapid visco analyzer (RAV) profile parameters of starch viscosity in hybrid combinations and parents were measured and statistically analyzed. Results showed that there were highly significant differences for the RVA profile parameters in both the hybrid rice combinations and their parents, among those parameters setback had the widest range of variations but the pasting temperature had the narrowest range of variations. The coefficients of variation of the starch RVA profile parameters of hybrids were smaller than that of the parents. The average of peak viscosity, trough viscosity, breakdown, final viscosity, peak time and pasting temperature of all the hybrid combinations were larger than that of the parents. However setback and consistency were smaller than that of the patents. Highly significant heterosis over high-parent was found in peak viscosity, and highly significant heterosis over mid-patent were found for trough viscosity, breakdown, final viscosity and consistency. Highly significant negative heterosis over mid-parent and positive heterosis over low-parent were found in both setback and peak time. Highly significant negative heterosis over low-parent was also found at pasting temperature. There were highly significant positive correlations between the hybrid rice combinations and the female parent and mid-parent value on peak viscosity, breakdown, setback and consistency. Significant positive correlations were also found between the hybrid rice combinations and mid-parent value on peak time. While there correlations to the male parent did not reach a significant level. Our data suggests that the starch viscosity properties in hybrid rice combinations were largely affected by the female parent compared to the male parent except for trough viscosity and peak time.
Abstract:As a traditional crop, adzuki bean is widely cultivated in China. It is not only an important export product, but also play an important role in modern planting systems. However, the genetic study of adzuki bean is much lagged, which limited the intensive development of this crop. In this paper, we reviewed the studies on germplasm collection, evaluation, breeding and molecular genetics of adzuki bean. The aim is to provide useful information in improving the genetic or genomics study and accelerate the breeding of adzuki bean in China.
Abstract:The genetic diversity and phylogenetic relationship of 27 oriental melon landraces of Zhejiang province were investigated by 81 phenotypic traits and cluster analysis. The results showed that Shannon-weaver genetic diversity coefficient of the 48 qualitative traits ranged from 0.17 to 1.98, and the variation coefficient of the 33 quantitative traits varied between 4.56% and 82.5%, implying the abundant genetic diversity. The cluster analysis based on the phenotypic traits indicated that the 27 oriental melon landraces could be divided into two groups at similarity coefficient of 0.30, well in correspondence with the growth period; one the other hand, the divisions of subgroups were independent of each other, but correlated with shape of fruit and seed and color of leaf, pericarp and its coating lines. The results of this study enrich the evaluation system and provide important information for the exploitation and utilization of excellent gene resources of melons.
Abstract:The phenotypic diversity of 6 populations of Rosa platyacantha in Eastern Tianshan mountains of Xinjiang were analyzed based on 11 phenotypic traits from leaves, flowers, fruits and seeds. The results showed there were significant differences in phenotypic traits both among and within populations. The mean phenotypic differentiation coefficient (VST) of 11 morphological traits among populations was 27.50%, indicating a more abundant phenotypic diversity within populations than among populations. The average variation coefficient (CV) of phenotype traits with 16.51% showed there was relatively lower variation of phenotypic traits in the populations. Both the Duncan’s test of CV and the principal component analysis of phenotypic traits indicated the traits involved fruits and seeds were the main factors account for phenotypic variations. Correlation analysis further showed there was no significant correlation between vegetative and productive traits. The cluster analysis showed six populations were not clustered according to geographic distances but due to the interaction of genetic variation and environmental factors, especially altitude here.
Abstract:In order to further improve evaluation and its effective utilization of rice landrace in Guangdong Province, we used 2974 accessions catalogued in the national genebank that 9 rice quality traits as basic data to study. The geographic distribution of rice quality traits were analyzed, and rice quality trait diversity among each area were compared, and the correlation between some ecological factors and rice quality traits were studied. The rice landrace in Guangdong province showed higher brown rice rate and milled rice rate, richer diversity of protein content, larger variation in gel consistency, and not many materials reached the national standard in amylose content. High-quality rice germplasm mainly distribute in Southcentral rice area of Guangdong province. The result also showed that amylose content, gelatinization temperature and gel consistency were the main impact index of rice quality formation. Humidity and temperature difference among areas were the main impact factors of rice quality formation. So, it is very important for high quality rice breeding and genetic background expanding to use rice landrace in Guangdong Province effectively.
Abstract:Simple sequence repeats (SSR) markers were adopted to evaluate genetic diversity of 43 accessions of Zhejiang barley landraces with different resistance to Fusarium head blight (FHB). Totally 87 alleles were revealed among the landraces with 29 SSR markers, 2~9 alleles could be detected at different SSR locus, with average of 3 alleles per SSR marker. The average polymorphism information content (PIC )was 0.3509, Shannon’s information index (I) was 0.6951, Nei’s gene diversity (H ) was 0.4268. Based on the data of SSR, the genetic similarity among 43 barley landraces was calculated. The mean of genetic similarity (GS) was 0.467, varying from 0.082 to 0.986. Cluster analysis showed that all the landraces were divided into 4 groups. Abundant genetic variation was observed among them and the genetic basis of two-rowed accessions varied greater than that of six-rowed ones. Great genetic variation was also deteted in FHB resistant and moderately-resistant landraces. The results of principal coordinates analysis and cluster anlysis revealed that the genetic relationship among these landraces was not in accord with their geographical origins.
Abstract:Rice blast is one of the most devastating diseases of rice. Utilization of resistance cultivars is the most effective, economical and environment-friendly approach to control the blast disease. In the past decade, with the development of deep researches in plant innate immunity, molecular biology of plant resistances, and genomics of rice and Magnaporthe oryzae, a range of plant defense-related genes which are implicated in host recognition of pathogens, host defense signaling, antifungal proteins and elicitors of the pathogens, etc., have been identified and cloned, providing some novel gene resources, breeding strategies and techniques for enhancing rice blast resistance. In this review, we summarized the main blast defense-related genes cloned recently for their enhancement in blast resistance and application in rice molecular breeding programs, and put forward a molecular breeding strategy which is to stack some key genes regulating different defense pathways through co-integration transformation and over-expressing of the target genes by means of transgenic techniques.
Abstract:A fragment of lectin-like receptor kinases gene was amplified in wheat leaf rust near-isogenic line TcLr45. The full length cDNA of the gene 2347bp was obtained using 3’ and 5’ RACE-PCR, based on the target sequence. This sequence had a full open reading frame, encoding 730 amino acids, named as LecRK-LR45. Software analysis showed that LecRK-LR45 had a typical structure of lectin-like receptor kinases, belonged to L type. Cluster analysis result indicated that LecRK-LR45 had a closer genetic relationship with lectin-like receptor kinases gene of Aegilops tauschii and wheat(Lr34), and farther with maize and arabidopsis. The cloning of this gene lies a foundation for researching the function of lectin-like receptor kinases in wheat.
Abstract:In this study, we report molecular characterization and expression patterns of AmLEA5 (AAW31666.1) under abiotic stresses, a gene cloned from cold- and drought-stressed Ammopiptanthus mongolicus by a modified solid subtractive hybridization method. Bioinformatic analysis shows that the gene encodes a group 5 late embryogenesis abundant protein (LEA).The overall length of AmLEA5 is 693 bp, and the cDNA contains a 297 bp ORF encoding a polypeptide of 98 amino acids with a calculated molecular mass of 10.6 kDa. AmLEA5, with more phosphorylation sites, is a kind of hydrophilic protein. The analysis of codon bias shows that AmLEA5 gene is bias toward the synonymous codons with A and T at the third codon position. Phylogenetic analysis indicates that AmLEA5 protein is most closed to Medicago truncatula LEA (ACJ84182.1) in genetic relationship. qRT- PCR analysis indicates that AmLEA5 is up-regulated by cold, drought, salt and hot stresses. Specifically, transcription of AmLEA5 accumulated more at the late stage of cold treatment. Intracellular localization analysis shows that AmLEA5 proteins tagged with yellow fluorescent proteins (YFP) is more likely localized in the cytoplasm and nucleus. Our results suggest that AmLEA5 may plays important roles in abiotic stresses responses, especially in cold tolerant mechanism in A. Mongolicus.
Abstract:A forward and reverse subtracted cDNA library of cucumber(Cucumis sativus L.) seedling leaves was constructed using suppression subtractive hybridization (SSH) method. The cucumber seedling leaves inoculated with Cladosporium cucumerinum on 2h、8h、20h、32h and72h were used as Tester, and that from untreated leave as Driver. Totally 200 SSH cDNA fragments were selected with Nested primer PCR. Through the DNA sequencing, we got 198 ESTs with high quality. After repeated and redundant sequences removed, 105 ESTs including 50 singletons and 55 contigs were obtained. Protein homology search in non-redundant (Nr) protein database revealed that 17 ESTs didn’t find homologous gene, 88 ESTs were highly homologous with known protein, accounting for 83.8% of all EST sequences, of which only 2 ESTs were unknown function protein. The positive rate of these ESTs was 75.0% detected by DIG Nonradioactive Nucleic Acid Labeling and Detection System. The function of these ESTs involved in energy and basic metabolism, signal transduction, protein and nucleic acid metabolism, photosynthesis and genes specifically induced under certain stress, etc. This study can provide a basis for further study of the cucumber genes resistance to Cladosporium cucumerinum.
Abstract:Heat shock protein 70 (HSP70) widely responds to stress environment and plays an important role in the promoting tumor cell apoptosis and in the control of normal mitosis growth of human cells. However, the physiological function of HSP70 start later in plant than in animal. Recent researches revealed that plant HSP70 is primarily involved in folding and maturation of nascent peptides, protein transporting, and the degradation of damage protein. Plant HSP70 plays an important role in environmental stress response, disease resistance, and development. This paper discussed the molecular functions of HSP70 in enhancing the plant stress tolerance, and systematically reviews latest progresses on molecular mechanism of plant HSP70 as well as improvement of plant resistance to facilitate broaden work.
Abstract:The phosphate transporter named CoPht1;1 was isolated from oil tea（Camellia oleifera’Xianglin4’）with the method of RT-PCR and RACE. Its expression under different phosphorus level at different time was checked with qRT-PCR. The CDS of CoPht1; 1 is 1 626 bp in length and it codes a predicted protein of 542 amino acids. The amino acid identity compared with other phosphate transporters is highly conserved and shows the highest similarity（88%）with the CoPht1;1 of Catharanthus roseus. Putative secondary structure and topology of the encoding protein have the main feature of transmembrane protein, and is consistent with Pht1 encoding protein in other species. The real-time RT-PCR result showed that expression of CoPht1;1 is induced by P-deficiency，and varied at different time. The results showed that CoPht1; 1 play an important role in phosphate uptake in camellia.
Abstract:Southern rust is one of the major diseases for maize in China. Deployment of resistant varieties is one of the most environment-friendliy and cost-saving methods. However, resistance genes used in current breeding programs mainly originated from the hybrid 78599. Inheritance of the resistance of CML470, a inbred line developed in CIMMYT, to southern rust was studied to identify novel resistance genes. Genetic analysis showed that the resistance of CML470 was controlled by a dominant gene (named as RppC), which was mapped to an interval on the terminal of chromosome 10 short arm flanked by closest SSR markers umc1380 and umc1291 with a distance of 3.5 cM and 8.8 cM, respectively. The resistance gene RppC was transferred from the inbred line CML470 to the elite line Chang7-2 by backcross with the aid of molecular marker- assisted selection.
Abstract:The phloem proteins play important role in the maintenance of morphology, material transportation and wound protection in higher plant. Here, cDNA sequences of phloem protein were obtained using RT-PCR technology from two celery varieties ‘Liu He Huang Xin Qin’ and ‘Mei Guo Xi Qin’. The full-length of the two phloem-protein genes were 546 bp, and encoded 181 amino acid residues, respectively. The nucleotide sequences alignment showed that there were 3 loci differences: 88G/A, 399T/C and 489T/C. The deduced amino acid sequences showed that there was 1 residue difference, 30T/A. Prediction of the proteins molecular weight were 19 kDa, and pI were 9.18, respectively. The phloem-proteins from ‘Liu He Huang Xin Qin’ and ‘Mei Guo Xi Qin’ have highly identity with Lycoris aurea. There were 5 leucine and 4 tryptophan amino acid residues in the conservative position, respectively. Real time RT-PCR analysis showed that the genes expression were tissue specificity, which mainly expressed in the stem and root.
Abstract:Eight male sterile lines and ten restorer lines of hybrid rice in South China were crossed to develop two half-diallel mating sets designed according to NCII and sixty-one F1s were obtained. These F1s were planted in 2005 and 2006 respectively, and the combining ability for yield traits in its eighteen parents were evaluated and screened by sixty-two SSR markers related to functional QTLs. The results showed that there were obvious differences in general combining ability among these parent lines, and four parent lines including Zhenshan97A, WanjinA, Zhilong and Guanghui3550 had elite general combining ability. There were thirty-six SSR molecular locus associated with combining ability of yield traits, and marker locus RM1, RM216, RM231 and RM542 were detected in two sets of materials. Among them, twenty-three were effect-increasing locus while others were effect-decreasing locus. Heterozygous locus of RM231 and RM209 were two marker locus of elite combining ability for yield with the maximum increasing effects, which increased 13.50% and 16.43% of yield in F1, respectively. The results could be directly used for yield improvement and choice of parents for developing hybrid rice in South China.
Abstract:In this paper, 41 unique wheat cultivars of Shandong Province were collected to construct DNA fingerprint database by SSR technique. The results showed that 69 alleles were detected with considerable polymorphism by 46 pairs of primers employed in the experimental design. For UPGMA cluster analysis using NTSYS, it was found that 41 kinds of materials could be divided into three groups with the threshold at genetic similarity of 0.68. This study indicates that (SSR technique) could effectively detect the genetic relationships among the various wheat cultivars, and it could meet the requirements for the construction of DNA fingerprint database for wheat, providing theory basis for collecting, storing, classifying, evaluating, and establishment of the core germplasm of wheat cultivars genetic resources of Shandong Province.
Abstract:Saccharum spontaneum L. is the most important wild resource in sugarcane breeding. It is necessary to identify and collect these wiId germplasm for a better understanding the genetic background of Saccharum spontaneum L.. In this study, 11 original clones which had never been collected from Yunnan province as well as 14 control clones which have a better polymorphism from national nursery of sugarcane germ were amplified with 10 SSR primers. As a result, a total of 233 bands were acquired. Out of these bands, 207 (89%) were polymorphic bands and 14 were specific bands for the new collected clones with contrast to the control materials. The new collected materials could not be separated from the control by the genetic similarity coefficients and UPGMA cluster analysis. The 25 clones were divided into three groups at 0.64 of genetic similarity coefficient: the first group consists of Longmen, River Village Saccharum spontaneum L. and Fujian Xianyou No.1; the second group was clustered by 19 materials from inland areas, including 9 new gathering resources: Shanggang, Tala, Anle, Menggen, Mangmei, Hehai, Huiluo, Lila and Manheng Saccharum spontaneum L., and 10 control from Yunnan, Sichuan, Vietnam, Laos and Thailand area; the third group includes three control materials, Hainan No.1, Hainan 92-2 and Huazhou of Guangdong S.spontaneum L.. The second group was divided into 3 sub-groups at 0.654 of genetic similarity coefficient. These results indicated that the 11 new collections of S.spontaneum L. showed abundant genetic diversity in comparison with the control. Therefore, it supposed that there were striking genetic differences among these materials derived from the distinctive geographical distribution and climatic circumstances of Yunnan province.
Abstract:Two parents of Brassica rapa （P1 ，P2 ） with significant difference in seed pod traits, and their corresponding four basic generations (P1, P2, F1, F2) were used to analyze the inheritance of seed pod correlated traits by applying mixed major-gene plus poly-genes inheritance model. The results indicated that both the seed pod length (SPL) and the seed beak length (SBL) were controlled by poly-genes with additive-dominant-epistatic effects (C-0 model), the heritabilities of poly-genes for SPL and SBL were 83.16% and 68.67%, respectively. The seed pod width (SPW) was controlled by two major genes with additive-dominant-epistatic effects plus poly-genes with additive-dominant-epistatic effects (E-0 model), the heritability of major genes was 20.40% and poly-genes was78.34%. The seed pod width (SPW) was less affected by environmental factors, conversely to the SPL and SBL, which influenced by environmental factors were 16.89% and 25.36%, respectively. This implies that in the genetic improvement of seed pod correlated trait poly-gene is a main factor and environment factor should also be mentioned.
Abstract:To discuss the application of 2 kinds of molecular markers in genetic diversity of cultivated Aquilaria Lam. The genetic diversity of 17 populations of Aquilaria Lam. from Hainan, Yunnan, Guangdong, Guangxi et al was analyzed using ISSR and AFLP. 14 ISSR primers and 8 AFLP primer combinations deteted 119 and 919 loci of which the number of polymorphic loci was 88 (73.95%) and 799 (86.94%) respectively. The results of ISSR and AFLP revealed Aquilaria Lam. possessed higher genetic diversity. Because of different mechanism of ISSR and AFLP, some differences existed in the results obtained. Genetic diversity parameters based on AFLP were higher than those based on ISSR, which was probably resulted from the higher detection efficiency of AFLP. Although some differences existed between the UPGMA dendrograms of ISSR and AFLP based on the Nei’s genetic distances, Mantel test revealed obvious correlation between genetic identity matrix between ISSR and AFLP (r=0.7705, P=0.0003). Both methods could be used to analyzed the genetic diversity of Aquilaria Lam.
Abstract:Nine polymorphic primer pairs were developed from 8,188 ESTs of Phalaenopsis from NCBI and used to analysis genetic diversity of 16 common Phalaenopsis materials on the market. The results indicated that 45 alleles loci were detected across 9 EST-SSR loci. The average number of alleles per EST-SSR locus was 5 with a range from 2 to 12. The value of allelic polymorphism information content (PIC) ranged from 0.527 to 0.981, on an average of 0.755 per EST-SSR marker. The genetic similarity of paired varieties ranged from 0.550 to 0.875, with average 0.728. The results showed that the commom Phalaenopsis varieties on the market had closer genetic relationgship with each other. Cluster analysis based on the UPGMA method indicated that the 16 Phalaenopsis varieties could be divided into four groups at similarities coefficient of 0.73, which was generally consistent with color. The Group Ⅰ included ten cultivars, such as Dtps. Queen Beer ‘Red Sky’, Dtps. Jiuhbao Red Rose, et al. The Group Ⅱ included four cultivars, such as P. Taida Salu, P. Fuller’s Sunset, Dtps. Chain Xen Queen, Dtps. Shin-yaun Golden Beauty. The Group Ⅲ included one cultivar P. Brother Sara Gold. The Group Ⅳ included one cultivar P. amabilis cv. Formosum. The results of the study will provide referrence for Phalaenopsis cultivar breeding.
Abstract:MicroRNAs constitute a recently discovered class of non-coding small RNAs, negatively regulate gene expression at the post-transcriptional leve l in eukaryotes. A large number of studies show that miRNAs play important roles in regulating many biological approaches. Bioinformatics prediction and analysis of miRNAs is one of the most important strategies for the discovery and identification in plant. The research content summarizes methods and strategies of bioinformatics prediction of miRNAs and their target genes,expounds the important role of bioinformatics in the study of plant miRNAs and is a foundation for future researches.
Abstract:According to the conservative sequences of the NBS-LRR disease-resistant genes (RGAs) , we isolated 10 homologous sequences (pp-01~10) from the mango variety ‘Jin Huang’ genomic DNA. Analysis of DNA sequences showed that the RGAs showed more variation in the 200~300-bp region, and Pi value was above 0.4. The clones of pp-01 to 10 showed great homologous differences, with the similarity from 11.0%~98.4% and divergence value from 1.6 to 1000.7 and 10 RGAs can be divided into two groups. pp-01~10 have an open reading frame, and the encoded protein contains the domain of the P-loop and Kinase-2a that were typical character of NBS gene families. pp-01~10 can be divided into two families, TIR-NBS-LRR and CC-NBS-LRR, by analysis of phylogenetic tree, and the homology was 22~60% compared with NBS genes of other known species.
Abstract:Abstract: The objective of this paper is to investigate the cytogenetic basis for origin of triploid apomictic Boehmeria tricuspis. We developed a study on the meiosis of PMC between the triploid apomictic B.tricuspis and the diploid sexual B.tricuspis. Rich trivalents were found in the PMC meiosis of triploid apomictic B.tricuspis showed it’s a autotriploid；In the sexual B.tricuspis,the PMC meiosis usually be normal.But a few were abnormal and some of their behavior maybe led to the occurrence of 2n gamete. The fusion of 2n gamete and n gamete may led to autotriploid apomictic plants. This is the cytogenetic basic event for the origin of triploid apomictic B.tricuspis.