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71.
The plant Asparagus racemosus is one of the most widely used sources of phytoestrogens because of its high content of the steroidal saponins, shatavarins I-IV, in roots. The dry root of A. racemosus, known as "Rak-Sam-Sip" in Thai, is one of the most popular herbal medicines, used as an anti-inflammatory, an aphrodisiac and a galactagogue. Recently, the interest in plant-derived estrogens has increased tremendously, making A. racemosus particularly important and a possible target for fraudulent labeling. However, the identification of A. racemosus is generally difficult due to its similar morphology to other Asparagus spp. Thus, accurate authentication of A. racemosus is essential. In this study, 1557-bp nucleotide sequences of the maturase K (matK) gene of eight Asparagus taxa were analyzed. A phylogenetic relationship based on the matK gene was also constructed. Ten polymorphic sites of nucleotide substitutions were found within the matK sequences. A. racemosus showed different nucleotide substitutions to the other species. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the matK gene was developed to discriminate A. racemosus from others. Only the 650-bp PCR product from A. racemosus could be digested with BssKI into two fragments of 397 and 253-bp while the products of other species remained undigested. Ten commercially crude drugs were analyzed and revealed that eight samples were derived from A. racemosus while two samples of that were not. Thus, the PCR-RFLP analysis of matK gene was shown to be an effective method for authentication of the medicinally phytoestrogenic species, A. racemosus. 相似文献
72.
Two clonal trial stands of Chinese Fir (Cunninghamia lanceolata) were used in this study, one was 19-year-old stand which included 38 clones, and the other was 17-year-old stand including 102 clones.The statistical analyses showed that there were very significant genetic variations in height, DBH,volume and ratio of heartwood(Rhw),wood basic density(ρb ) of the clones in the two stands. The repeatability of clones was in median to high level,and the genetic CV was different over the all five traits.There were very significant phenotypic and genetic correlations among height,DBH and volume,and negative correlations among growth, Rhw andρb.The selection method experiment indicated that index selection could improve volume, Rhw andρb,showing synthetically superior selection effects compared to any individual trait selection methods. 相似文献
73.
对内蒙古农业大学校园内表现花器绿变症状的菊花样品进行采集和DNA提取,应用植原体16S rRNA基因和rp基因的引物进行巢式PCR扩增,从感病样品中分别扩增得到了长度均约为1.2 kb的片段。序列一致性分析表明,菊花绿变植原体16S rRNA基因与翠菊黄化植原体匈牙利风信子株系(GenBank登录号MN080271)、印度玉米株系(KY565571)、印度繁缕株系(KC623537)和印度马铃薯株系(KC312703)的核酸一致性最高,为99.9%,rp基因序列与翠菊黄化植原体立陶宛洋葱株系(GU228514)的核酸一致性最高,为99.8%。基于16S rRNA基因和rp基因构建系统进化树时发现,菊花绿变植原体均与16SrI-B亚组成员聚为一起。16S rRNA基因相似性系数分析表明,菊花绿变植原体与洋葱黄化植原体(AP006628)的相似性系数最高为1.00,洋葱黄化植原体(AP006628)在分类上属于16SrI-B亚组。因此,我们可以确定该菊花绿变植原体属于16SrI-B亚组。这是我国首次报道菊花绿变病的发生。 相似文献
74.
In order to clarify the epidemiology of bovine protothecal mastitis, 30 Prototheca zopfii mastitis isolates were genetically investigated. Based on the 18S rDNA, which allows a differentiation of the former species P. zopfii in two distinct P. zopfii genotypes and Prototheca blaschkeae sp. nov., newly developed genotype-specific PCR-assays as well as RFLP-assays were applied.
All mastitis isolates investigated could be assigned to P. zopfii genotype 2 suggesting that this genotype is the aetiological agent of bovine Prototheca mastitis. 相似文献
75.
Molecular cytogenetic identification of wheat-Elymus tsukushiense introgression lines 总被引:3,自引:0,他引:3
Elymus tsukushiense Honda (syn. Roegneria kamoji C. Koch) (2n = 6x = 42, StsStsHtsHtsYtsYts) is a hexaploid species, distantly related to bread wheat Triticum aestivum L. em Thell (2n = 6x = 42, AABBDD). Apart from
the delineation of evolutionary relationships, this species is a potential source of resistance to scab, a devastating disease
of wheat caused by Fusarium graminearum Schw. A standard C-banded karyotype was established identifying all 21 chromosome
pairs of E. tsukushiense. By using C-banding and genomic in situ hybridization analyses, three wheat-E. tsukushiense chromosome
addition lines, one ditelosomic addition line, and one disomic substitution line were identified in BC2 progenies from wheat × E. tsukushiense hybrids. Twenty DNA markers specific for the seven homoeologous groups of the Triticeae
were used to determine the homoeology of the added E. tsukushiense chromosomes. The E. tsukushiense chromosomes in the addition
lines NAU702, NAU703, and NAU701 were identified as belonging to homoeologous groups 1, 3, and 5, and thus, were designated
as 1Ets#1, 3Ets#1, and 5Ets#1, respectively. NAU751 was identified as a disomic substitution line with chromosome 3A of wheat
replaced by chromosome 3Ets#1. Line NAU702 has a high level of resistance to scab and will be used in chromosomal engineering
and development of improved wheat germplasm for scab resistance breeding.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
76.
Identification of a RAPD marker linked to a brown planthopper resistance gene in rice 总被引:12,自引:0,他引:12
We report the tagging of a brown planthopper (BPH) resistance gene (Bph–1) in rice using RAPD and RFLP markers. The Korean
rice variety ‘Gayabyeo’ has dominant duplicate genes including Bph–1 conferring resistance to biotype 1 of BPH. Bulked segregant
RAPD analysis was employed for rapid identification of DNA markers linked to resistance genes. For tagging these two genes,
an F2F3 population from a ‘Gayabyeo’ × ‘Nagdongbyeo’ cross was developed and evaluated for BPH resistance. Three bulked DNAs
from two groups of homozygous BPH resistant (each for Bph–1 and the other unknown gene) and homozygous susceptible F2 plants
were analyzed by RAPD using 140 random oligomers. One primer, OPD–7 yielded a 700-bp fragment that was present in Gayabyeo
and resistant F2 plants (homozygous for Bph-1 locus) but absent in Nagdongbyeo and susceptible F2 plants. Cosegregation of
this marker with Bph-1 was verified using an F2 population segregating for Bph-1. Chromosomal regions surrounding the Bph-1
were examined with additional RFLP and microsatellite markers on chromosome 12 to define the location of the RAPD marker and
Bph-1. Use of this RAPD marker could facilitate early selection of resistant lines for BPH.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
77.
Masumi Yamagishi Motoyasu Otani Mariko Higashi Yoshimichi Fukuta Kiichi Fukui Takiko Shimada 《Euphytica》1998,103(2):227-234
Diallel analysis has revealed that anther culturability in rice (Oryza sativa L.) is a quantitative trait controlled by the
nuclear genome. Mapping of anther culturability is important to increase the efficiency for green plant regeneration from
microspores. In the previous study, we detected distorted segregation of RFLP markers in rice populations derived from the
anther culture of an F1 hybrid between a japonica cultivar ‘Nipponbare’ and an indica cultivar ‘Milyang 23’. To clarify the association between chromosomal
regions showing distorted segregation and anther culturability, the anther culturability of doubled haploid lines derived
from the same cross combination was examined, and the association between alleles of the RFLP markers, which exhibiting the
most distorted segregation on chromosomes 1, 3, 7, 10 and 11, and the anther culturability was evaluated. One region on chromosome
1 was found to control callus formation from microspores, and one region on chromosome 10 appeared to control the ratio of
green to albino regenerated plants. In both regions, the Nipponbare allele had positive effects. Three regions on chromosomes
3, 7 and 11, however, showed no significant effect on anther culturability.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
78.
RFLP analysis of a PCR amplified region of chloroplast DNA in eggplant and related Solanum species 总被引:1,自引:0,他引:1
RFLP analysis of a PCR amplified 3.2-kbp region of cpDNA bounded by the conserved sequences in rbc L and ORF 106 was performed
in eggplant (Solanum melongena), its related Solanum species, S. incanum, S. virginianum (= S. surattense), S. torvum, S.
aethiopicum (= S. gilo), S. aethiopicum (= S. integrifolium), S. violaceum (= S. indicum), S. violaceum (= S. sanitwongsei)
and S. mammosum and the reciprocal hybrids between S. aethiopicum (= S. integrifolium) and S. melongena 'Uttara'. The target
region of cpDNA was amplified correctly by PCR. The amplified products were digested with each of 10 restriction enzymes (Alu
I, Ase I, BamH I, Hinf I, Msp I, Rsa I, ScrF I, Sty I, Taq I and Xba I). Variations of restriction patterns among the species
were recognized after digesting the amplified products with each of the seven restriction enzymes, Taq I, Alu I, Rsa I, Sty
I, Ase I, Hinf I and Xba I. The restriction patterns divided the examined nine species into the following five clusters, 1)
S. melongena and S. incanum, 2) S. virginianum (= S. surattense), 3) S. torvum, 4) S. aethiopicum (= S. gilo), S. aethiopicum
(= S. integrifolium), S. violaceum (= S. indicum) and S. violaceum (= S. sanitwongsei) and 5) S. mammosum. The restriction
pattern with Alu I in each of the reciprocal hybrids between S. melongena 'Uttara' and S. aethiopicum (= S. integrifolium)
was identical with that of seed parent. The present study demonstrated the availability of the PCR-RFLP analysis of cpDNA
for assessing taxonomic relationships and identifying cytoplasmic parentage of interspecific hybrids in eggplant and related
Solanum species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
79.
Linkage analysis of RFLP markers for clubroot resistance and pigmentation in Chinese cabbage (Brassica rapa ssp. pekinensis) 总被引:15,自引:0,他引:15
A restriction fragment length polymorphism (RFLP) – based linkage map of Chinese cabbage (Brassica rapa ssp. pekinensis) (2n=20)
including two agronomic traits, clubroot resistance and orange-yellow pigmentation, was constructed using doubled haploid
parents. The total linkage distance was 735 cM; 63 loci were distributed into ten linkage groups. Clubroot resistance of the
parental line T136-8 to the current pathotype, race 2, was predominantly controlled by a single dominant gene that originated
from European turnip. The locus for clubroot resistance by the dominant major gene (CRa) was mapped on linkage group 3, and
RFLP loci HC352b and HC181 were located 3 cM and 12 cM from it, respectively. The locus HC352b was identified by a 4.4 Kb
Eco R I fragment, which segregated for null allele. The absence of an allelic fragment in HC352b could be interpreted by deletion
in the resistance source; homozygotes for CRa could be efficiently selected by detecting null types for the marker. Orange-yellow
pigmentation expressed in head inner leaves and petals was governed by a single recessive gene. The locus (Oy) for the pigmentation
was mapped on linkage group 1, being located 17–19 cM from three RFLP loci that were closely linked to each other. The linkage
analysis for clubroot resistance and unique pigmentation revealed some informative RFLP markers. Identification of molecular
markers for clubroot resistance and other agronomically important traits would provide useful information in breeding programs
of Chinese cabbage.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
80.
A. R. Barr K. J. Chalmers A. Karakousis J. M. Kretschmer S. Manning R. C. M. Lance J. Lewis S. P. Jeffries P. Langridge 《Plant Breeding》1998,117(2):185-187
Cereal cyst nematode (CCN) ( Heterodera avenae Woll.) is an economically damaging pest of barley in many of the worlds cereal growing areas. The development of CCN-resistant cultivars may be accelerated with the application of molecular markers. Three resistance genes against the pest have been mapped previously to chromosome 2 ( Ha 1, Ha 2 and Ha 3). In this study, a third gene present in the Australian barley variety 'Galleon' derived from the landrace 'CI3576' was located. Segregation analysis of CCN resistance data derived from doubled haploid populations of the cross 'Haruna Nijo'×'Galleon' identified a single major locus controlling CCN resistance in the variety 'Galleon'. This locus mapped to the long arm of chromosome 5H estimated to be 6.2 cM from the known function restriction fragment length polymorphism marker XYL (xylanase). While five genes for CCN resistance, including Ha2, have been mapped to group 2 chromosomes in the Triticeae, no gene other than Ha4 has been identified on group 5 chromosomes. 相似文献