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1.
Ten EST-SSRs previously isolated from Pyrus were used to identify 81 P. communis, 13 P. pyrifolia and 20 P. ussuriensis or P. × bretschneideri accessions. Cross-transference of these EST-SSRs was high in these species. PYC-008 and PYC-004 were the least informative
SSRs in each of the pear species and were monomorphic in P. pyrifolia while PYC-013, PYC-002 and PYC-009b were the most informative in all species. EST-SSRs were very valuable for identification
of incorrectly identified accessions, failed grafts and sets of synonyms in each of the species. Unsuspected relationships
were uncovered, including a parental relationship between ‘Anjou’ and ‘Farmingdale’, a clonal relationship between ‘Berger’
and ‘Bartlett’, and a very close relationship between ‘Beurre Superfin’ and ‘Doyenne du Comice’. One SSR marker was different
in one of three sports of ‘Doyenne du Comice’ (‘Doyenne du Comice Crimson Gem’) and in one of two sports of ‘Anjou’ (‘Gebhard
Red’ red skin sport of ‘Anjou’). UPGMA cluster analysis separated the pear accessions into a large European cluster and an
Asian group mostly according to common ancestry, geographical origin or time of ripening. High cross-transference of EST-SSRs
in Pyrus species is very valuable for germplasm management in such a highly diverse collection as found at the NCGR Pyrus genebank in Corvallis, OR. 相似文献
2.
Gert Poulsen Claus Holten Roland von Bothmer 《Genetic Resources and Crop Evolution》2007,54(5):1105-1115
Dead seeds of a fodder beet cultivar ‘Elvetham’ stored under ambient conditions since 1880 were compared to a homonymous sample
preserved in an on-farm situation in Denmark. DNA was isolated from single seeds and successfully applied to Amplified Fragment
Length Polymorphism (AFLP) analysis of the accessions. Six primer pairs were used to determine the similarity between the
two accessions based on 112 polymorphic bands. Furthermore, similarity among seven cultivars of fodder beets representing
the main types used in Scandinavia at the end of the 19th century was determined. This analysis was based on 152 polymorphic
bands. Differentiation among the seven cultivars was determined to a mean G
ST value of 0.438, while G
ST between the two ‘Elvetham’ accessions was 0.266. A principal coordinate analysis based on jaccards similarity index illustrates
that the two ‘Elvetham’ accessions are different from each other. The differentiation is higher than the value found between
two separate ‘Eckerndorfer’ accessions. The results indicate that the cultivated accession has changed. Additionally, the
value of applying old dead seed material for documentation in gene banks is demonstrated.
During the analysis it was found that DNA isolated from seeds and leaves behaved differently in the AFLP process, however,
the two fractions assigned to their common accession. 相似文献
3.
Nidhi Rawat Vijay K. Tiwari Neelam Singh Gursharn S. Randhawa Kuldeep Singh Parveen Chhuneja Harcharan S. Dhaliwal 《Genetic Resources and Crop Evolution》2009,56(1):53-64
Grains of 80 accessions of nine species of wild Triticum and Aegilops along with 15 semi-dwarf cultivars of bread and durum wheat grown over 2 years at Indian Institute of Technology, Roorkee,
were analyzed for grain iron and zinc content. The bread and durum cultivars had very low content and little variability for
both of these micronutrients. The related non-progenitor wild species with S, U and M genomes showed up to 3–4 folds higher
iron and zinc content in their grains as compared to bread and durum wheat. For confirmation, two Ae. kotschyi Boiss. accessions were analyzed after ashing and were found to have more than 30% higher grain ash content than the wheat
cultivars containing more than 75% higher iron and 60% higher zinc than that of wheat. There were highly significant differences
for iron and zinc contents among various cultivars and wild relatives over both the years with very high broad sense heritability.
There was a significantly high positive correlation between flag leaf iron and grain iron (r = 0.82) and flag leaf zinc and grain zinc (r = 0.92) content of the selected donors suggesting that the leaf analysis could be used for early selection for high iron
and zinc content. ‘Chinese Spring’ (Ph
I
) was used for inducing homoeologous chromosome pairing between Aegilops and wheat genomes and transferring these useful traits from the wild species to the elite wheat cultivars. A majority of
the interspecific hybrids had higher leaf iron and zinc content than their wheat parents and equivalent or higher content
than their Aegilops parents suggesting that the parental Aegilops donors possess a more efficient system for uptake and translocation of the micronutrients which could ultimately be utilized
for wheat grain biofortification. Partially fertile to sterile BC1 derivatives with variable chromosomes of Aegilops species had also higher leaf iron and zinc content confirming the possibility of transfer of required variability. Some of
the fertile BC1F3 and BC2F2 derivatives had as high grain ash and grain ash iron and zinc content as that of the donor Aegilops parent. Further work on backcrossing, selfing, selection of fertile derivatives, leaf and grain analyses for iron and zinc
for developing biofortified bread and durum wheat cultivars is in progress.
Nidhi Rawat, Vijay K. Tiwari, and Neelam Singh have contributed equally to the work. 相似文献
4.
Margarita Mauro-Herrera Alan W. Meerow Lalith Perera Joanne Russell Raymond J. Schnell 《Genetic Resources and Crop Evolution》2010,57(2):203-217
A prior analysis of eight coconut cultivars with 15 microsatellite (SSR) markers drew unexpected relationships between two
of the out-crossing tall cultivars evaluated: ‘Atlantic Tall’ and ‘Panama Tall’. We further investigated the relationships
between these eight cultivars by increasing the number of individuals studied (particularly for ‘Atlantic Tall’ and ‘Panama
Tall’), by including 28 more molecular markers, and by adding two other cultivars to our analysis. Our results show that five
to ten coconut individuals do not represent a dependable sample to withdraw conclusions regarding cultivar/variety relationships,
particularly when studying out-crossing genotypes. As suggested in the prior study, a high level of hybridization was observed
between the ‘Atlantic Tall’ and ‘Panama Tall’ cultivars. However, at this time we were able to identify distinct groups for
each one of these two cultivars. The two clustering methods used (Neighbor Joining, NJ and Unweighted Pair Group Method with
Arithmetic mean, UPGMA) produced dendrograms that resolved contrasting cultivar relationships, especially for the ‘Atlantic
Tall’ and ‘Panama Tall’ cultivars. We discuss the implications of our results in regard to current scenarios of coconut domestication
and future considerations when assessing genetic relationships among different varieties. 相似文献
5.
Eight genomic SSR markers with a M13 tail attached were used to assess the genetic diversity of 72 Ussurian Pear accessions
(Pyrus ussuriensis Maxim.) in China. The M13-tailed method was effective in discriminating all the 32 wild accessions. All the 40 Ussurian Pear
cultivars could be successfully discriminated with the exception of 4 sets of synonymies or spots. A total of 108 alleles
were obtained with an average of 13.5 per locus. The expected heterozygosity, observed heterozygosity, and power of discrimination
were 0.78, 0.63, and 0.86 respectively. Three triploid cultivars (‘Anli’, ‘Ruan’er’, and ‘Pitaiguo’), and one wild accession,
P. ussuriensis ‘Xilin-3’, showed three alleles at some SSRs. The number of alleles and observed heterozygosity per locus for 40 Ussurian
Pear cultivars were 9.1 and 0.62, respectively, lower than the values of 32 wild accessions which were 11.3 and 0.65, respectively.
A dendrogram based on the SSR genotypes was obtained, showing two major groups corresponding to cultivated group and wild
group. All the cultivars fell into the cultivated group. Some subgroups (Nanguoli subgroup, Zhibazi subgroup, Xiangshuili
subgroup, Balixiang subgroup, Anli subgroup) could be found in the cultivated group. A very close relationship between ‘Huagaili’
and ‘Miansuan’, and a close relationship between ‘Anli’ and a wild accession, P. ussuriensis ‘Huangshanli’ could be found in Anli subgroup. ‘Nanguoli’ and ‘Xiaowuxiang’ showed a close relationship with at least one
identical allele at each locus with the exception of NH015a. 相似文献
6.
Parveen Chhuneja Satinder Kaur R. K. Goel M. Aghaee-Sarbarzeh M. Prashar H. S. Dhaliwal 《Genetic Resources and Crop Evolution》2008,55(6):849-859
Aegilops umbellulata acc. 3732, an excellent source of resistance to major wheat diseases, was used for transferring leaf rust and stripe rust
resistance to cultivated wheat. An amphiploid between Ae. umbellulata acc. 3732 and Triticum durum cv. WH890 was crossed with cv. Chinese Spring Ph
I
to induce homoeologous pairing between Ae. umbellulata and wheat chromosomes. The F1 was crossed to the susceptible Triticum aestivum cv. ‘WL711’ and leaf rust and stripe rust resistant plants were selected among the backcross progenies. Homozygous lines
were selected and screened against six Puccinia triticina and four Puccinia striiformis f. sp. tritici pathotypes at the seedling stage and a mixture of prevalent pathotypes of both rust pathogens at the adult plant stage. Genomic
in situ hybridization in some of the selected introgression lines detected two lines with complete Ae. umbellulata chromosomes. Depending on the rust reactions and allelism tests, the introgression lines could be classified into two groups,
comprising of lines with seedling leaf rust resistance gene Lr9 and with new seedling leaf rust and stripe rust resistance genes. Inheritance studies detected an additional adult plant
leaf rust resistance gene in one of the introgression lines. A minimum of three putatively new genes—two for leaf rust resistance
(LrU1 and LrU2) and one for stripe rust resistance (YrU1) have been introgressed into wheat from Ae. umbellulata. Two lines with no apparent linkage drag have been identified. These lines could serve as sources of resistance to leaf rust
and stripe rust in breeding programs. 相似文献
7.
The genus Arachis is divided into nine taxonomic sections. Section Arachis is composed of annual and perennial species, while section Heteranthae has only annual species. The objective of this study was to investigate the genetic relationships among 15 Brazilian annual
accessions from Arachis and Heteranthae using RAPD markers. Twenty-seven primers were tested, of which nine produced unique fingerprintings for all the accessions
studied. A total of 88 polymorphic fragments were scored and the number of fragments per primer varied from 6 to 17 with a
mean of 9.8. Two specific markers were identified for species with 2n = 18 chromosomes. The phenogram derived from the RAPD data corroborated the morphological classification. The bootstrap analysis
divided the genotypes into two significant clusters. The first cluster contained all the section Arachis species, and the accessions within it were grouped based upon the presence or absence of the ‘A’ pair and the number of chromosomes.
The second cluster grouped all accessions belonging to section Heteranthae. 相似文献
8.
This study is focused in the main chestnut growing areas from north- to south-western Spain. We studied 50 accessions corresponding
to 22 cultivars named by local growers; 11 from Andalucía, 9 from Castilla-León, and 2 from Extremadura. These were compared
with 22 types classified previously in Galicia (82 accessions). Ten morphological traits and five isoenzyme systems were used
to classify them and establish genetic relationships. A lower genetic variability has been found in Extremadura (middle Spain)
and Andalucía (south) than in Galicia (north western) which may be because of the lower importance of the crop in those areas
and the geographic barriers between them. Galicia could be the origin of the types found in Castilla-León, Extremadura, and
south-western Andalucía, and the types found in Central Andalucía were closer to those found in Castilla-León and Extremadura.
Most accessions studied (117/132) could be classified positively, making 37 out of 44 cultivars found from northern to southern
Spain. Three groups of synonymies were found in Castilla-León: ‘Brava’ and ‘Negral’, ‘Gallego’ and ‘Injerto’, and ‘Rapega’
and ‘Verdello’. Most of the Spanish types have been propagated as a principal clone. Variability within the types is important
and must be considered to select the best clones as cultivars. 相似文献
9.
Yong Gao Tingting Li Yun Zhao Wei Liu Maolin Wang 《Genetic Resources and Crop Evolution》2010,57(4):481-485
A novel dwarf mutant of Brassica napus L. em. Metzg., named NDF-1, was derived from a high doubled haploid line ‘3529’ of which seeds were jointly treated with chemical inducers and fast
neutron bombardment. The germination results showed that the germination of NDF-1 was insensitive in response to exogenous gibberellic acid 3 (GA3). The studies on growth response to exogenous GA3 showed that NDF-1 seeding has at least 10-fold insensitivity than the wild-type. Moreover, no matter what concentrations of GA3 were added to the seedlings and adult plants, the NDF-1 could not restore the wild type phenotype. These results indicated that the B. napus dwarf mutant NDF-1 was GA-insensitive mutant. The histological observations showed that the key reason of leading NDF-1 to dwarf was the reduction of hypocotyls and stems cell numbers. 相似文献
10.
Tesema Tanto Hadado Domenico Rau Elena Bitocchi Roberto Papa 《Genetic Resources and Crop Evolution》2009,56(8):1131-1148
In Ethiopia, barley is generally grown in two different planting seasons per year: during the long rainy season (Meher) and the short rainy season (Belg). The aim of the present study was to assess for the first time the role of this ‘two-season system’ on the structure of
the genetic diversity of the Ethiopian barley landraces. We characterised 3,170 individual genotypes from 106 landrace populations
using eight morphological spike traits. The diversity within population was higher in the season where barley is more important
(Belg), and in general, where its cultivation is in larger plots because of weaker ‘competition’ with others crops. This indicates
that barley diversity has a complex relationship with variations in the surrounding agro-ecosystem. Overall, the divergence
between the two seasons was quite small (3.4%), suggesting that seed flow does not occur independently across the years within
the two seasons. This would affect the amount of mutations and historic recombination that have accumulated within these populations. 相似文献
11.
To evaluate the genetic diversity and to clarify the genetic relationships of Japanese peach cultivars, we analyzed the amplified
fragment length polymorphism (AFLP) and traced the pedigree of 17 Japanese commercial peach cultivars and six traditional
accessions. Sixteen AFLP primer combinations produced a total of 837 fragments and 146 polymorphic bands with a polymorphism
percentage of 17.5%. All of the peach accessions could be identified from differences in at least 10 polymorphic bands. A
cluster analysis showed that all the Japanese commercial peach cultivars, except ‘Kiyomi’ and ‘Jichigetsuto’, formed a major
group consisting of three sub-groups. Of the six traditional accessions, four were genetically distant from the Japanese commercial
peach cultivars while two accessions from China were classified into the Japanese commercial peach cultivars group. Both the
AFLP analysis and pedigree tracing suggested that Japanese commercial peach cultivars are mainly derived from ‘Shanhai Suimitsuto’,
one of the traditional accessions from China. Although the genetic relationships revealed by AFLP were generally in agreement
with those shown by the pedigree information, some contradictions were found. Combining the AFLP results and pedigree information
can provide a better understanding of the genetic relationships of Japanese peach cultivars. 相似文献
12.
Cengiz Toker 《Genetic Resources and Crop Evolution》2009,56(1):7-12
Two distinct chickpeas of the domestic chickpea, C. arietinum L., exist and are referred to as ‘desi’ or microsperma and ‘kabuli’ or macrosperma. Cicer reticulatum Ladiz. is considered to be the wild progenitor of the domestic chickpea. However, the morphological variation in 18 original
accessions of C. reticulatum is narrower than those of the domestic chickpeas. The aim of the study is to increase the variability in C. reticulatum. In M2 generation, a mutant with white flower color was isolated despite of the fact that the parent has the pink flower. Although
seed coat color of the parent was dark brown, the mutant was cream like ‘kabuli’ chickpea. It is commonly accepted that the
large seeded domestic ‘kabuli’ chickpeas originated from the small seeded ‘desi’ chickpeas, but the induced mutants (white
flower and cream seed coat color) of C. reticulatum may suggest an additional path for the evolution of ‘kabuli’ chickpea. ‘Kabuli’ chickpeas could have originated from spontaneous
mutants of C. reticulatum. In M3 generation, multipinnate leaf, erect growth habit, green seed and double-podded chickpeas were isolated. Among these progenies,
morphologic variability increased and approached domesticated chickpea. Based on historical records and the induced mutants
obtained from this study, the domestic ‘kabuli’ chickpea could have directly emerged from C. reticulatum in ancient Eastern Turkey. 相似文献
13.
L. Pecetti M. Romani L. De Rosa E. Franzini G. Della Marianna F. Gusmeroli A. Tosca R. Paoletti E. Piano 《Genetic Resources and Crop Evolution》2008,55(7):939-947
A recent approach to restoration of degraded mountain landscapes (e.g. ski slopes) recommend to sow seed mixtures including
‘site-specific’ species, i.e. native germplasm adapted to the prevailing conditions and ecologically compatible with the area
of intervention. To better exploit the potential of these species and enhance their spread in revegetation projects, deeper
knowledge is needed, however, on the existing variation in their germplasm, particularly for economically useful traits such
as seed yield. Snow clover is one of the recommended ‘site-specific’ legumes. This study evaluated 12 populations of snow
clover, collected in three valleys of the Rhaetian Alps, Italy, to assess their variation and highlight any promising material.
The evaluation encompassed a mountain and a lowland site, to verify the behaviour of the germplasm also in one environment
markedly different from that of origin. Differences among valleys were observed for flower colour, growth habit and type,
flowering time and susceptibility to mildew, although the overall pattern of phenotypic diversity was similar among valleys.
Some effect of the evaluation site on the expression of morphological and seed production traits, and on the overall diversity,
was also evident. Furthermore, the lowland site experienced very high plant mortality towards the end of the first growing
season. Individual populations proved a valuable source of variation for seed production. Some populations, in particular,
were worth of attention for a possible selection of high-seed-yielding snow clover cultivars. An assessment of the mating
system suggested a lack of self-tripping or an almost absolute self-incompatibility in snow clover. 相似文献
14.
Zizania latifolia, which belongs to the tribe Oryzeae, has been cultivated for more than 2000 years and has historically been used in China
mainly as an aquatic vegetable. In China, the largest area under cultivation of this plant is located in the regions surrounding
Tai Lake, in the provinces of Jiangsu and Zhejiang. Two main types of cultivars have been developed, in one the shoots can
be harvested only once, in the fall; in the other, the shoots may be harvested twice in the fall and once the following summer.
Z. latifolia can be bred and conserved through clonal propagation as a means of preventing infection of flowering stems by the epiphyte
Ustilago esculenta. At the end of the harvest period, healthy individuals and the plants with black spots in the shoots are removed, and those
with a healthy clone will be identified and selected as ‘seed’ for the next year. 相似文献
15.
Claire E. Marks Pauline Y. Ladiges Ed Newbigin 《Genetic Resources and Crop Evolution》2011,58(6):797-803
Nicotiana section Suaveolentes (Solanaceae) currently includes 28 species and subspecies that are endemic to Australasia and the South
Pacific and one African species, N. africana. The section is monophyletic and of allotetraploid origin, but relationships among the species in it and its diploid progenitors
are poorly understood. Here we report chromosome numbers for 20 of the 29 taxa from the Suaveolentes, including a count for one recently proposed species for which no number has previously been available. Many of the published
chromosome numbers for the Suaveolentes are confirmed in this study. However, six counts were different from the published
numbers including n = 15 for N. maritima and N. suaveolens, which is a new chromosome number for the genus. Nicotiana goodspeedii and N. rotundifolia were n = 16, and the same number was found in the suggested species N. sp. ‘Corunna’. Nicotiana suaveolens contains polyploid races of n = 32 and here we report the probable existence of an n = 31 race as well. Karyotypic variation
within species and within the section is apparently much greater than previously thought and further investigation is warranted. 相似文献
16.
South Italy is still a centre of diversity for melons but new cultivars progressively replace its traditional landraces. The
area of Salento is important for several typical old crops as the cucumber melon ‘Meloncella’ (Cucumis melo L. var. chate (Hasselq.) Filov) traditionally cultivated for its unripe fruits. Information on cultivation, quality and variation of this
Apulian landrace (probably the last relic of a wider cultivation in Europe) is reported. A strategy for its characterization
and safeguarding is in progress at the genebank of IGV of Bari (Italy). 相似文献
17.
Houyang Kang Meiyu Zhong Quan Xie Haiqin Zhang Xing Fan Lina Sha Lili Xu Yonghong Zhou 《Genetic Resources and Crop Evolution》2012,59(3):445-453
Trigeneric hybrids may help establish evolutionary relationships among different genomes present in the same cellular-genetic
background, and also offers the possibility to transfer different alien characters into cultivated wheat. In this study, a
new trigeneric hybrid involving species from the Triticum, Psathyrostachys and Secale was synthesized by crossing wheat-P. huashanica amphiploid (PHW-SA) with wheat-S. cereale amphiploid (Zhongsi 828). The crossability of F1 hybrid was high with 35.13%, and the fertility was 41.95%. The morphological characteristics of F1 plants resembled the parent Zhongsi 828. The trigeneric hybrids pollen mother cells (PMCs) regularly revealed averagely 19.88
univalents, 9.63 ring bivalents, 3.97 rod bivalents, 0.60 trivalents and 0.03 tetravalents per cell. Multivalents consisted
of trivalents and tetravalents can be observed in 52.7% of cells. A variation of abnormal lagging chromosome, micronuclei
and chromosome bridge were formed at anaphase I and telophase II. The mean chromosomes number of F2 progenies was 2n = 46.13, and the distribution range was 42–53. GISH results revealed that most F2 plants had 6–12 S. cereale chromosomes, and only 0–2 P. huashanica chromosomes were detected. The results indicated that S. cereale chromosomes can be preferentially transmitted in the F2 progenies of trigeneric hybrid than P. huashanica chromosomes. A survey of disease resistances revealed that the stripe rust resistance from the PHW-SA were completely expressed
in the F1 and some F2 plants. The trigeneric hybrid could be a useful bridge for the transference of P. huashanica and S. cereale chromatins to common wheat. 相似文献
18.
Forty-seven samples of date palm (Phoenix dactylifera L.) collected from eight locations in Egypt were studied using four sets of amplified fragment length polymorphism (AFLP)
markers with near infrared fluorescence labeled primers. These samples belonged to 21 named accessions and 9 of unknown pedigrees.
A total of 350 bands were scored and 233 (66.6%) were polymorphic. Twenty-seven Egyptian accessions and ‘Medjool’and ‘Deglet
Noor’accessions from California could beclassified into the major cluster. This major cluster may represent a major group
of date palm germplasm in North Africa. There were four other clusters, each containing one or two accessions. The variety
‘Halawy’and one accession of unknown provenance were most likely from hybridization between two clusters. Six groups of accessions
of which had the same names, revealed similar but not identical AFLP profiles suggesting these accessions might derive from
seedlings rather thanthrough clonal offshoot propagation. 相似文献
19.
Łukasz Stępień Volker Mohler Jan Bocianowski Grzegorz Koczyk 《Genetic Resources and Crop Evolution》2007,54(7):1499-1506
Fifty-three wheat cultivars have been genotyped using 24 SSR (simple sequence repeat) markers in order to evaluate genetic
similarities among Polish wheats, i.e. 53 spring and winter cultivars; ‘Chinese Spring’ was taken as reference. ll but one
SSR marker allowed to identify DNA polymorphisms, giving in total 166 alleles (including nulls), from 3 to 13 alleles per
marker with mean of 7.22. Based on marker data, genetic similarities were calculated and a dendrogram was created. ‘Spring’
cultivars were less diverse than winter ones, showing the biggest similarity to ‘Chinese Spring’. Four sister cultivars (Nutka,
Tonacja, Zyta and Sukces), formed a cluster of very similar materials, of which Zyta and Sukces had the highest similarity
indices. Parental lines Jubilatka and SMH 2182 were more distant from each other (genetic similarity of 0.227). It was possible
to differentiate all the wheats using only four SSR markers: Xgwm186, Xgwm389, Xgwm459 and Xgwm577. 相似文献
20.
Zhi-Xin Li E. M. Septiningsih S. M. Quilloy-Mercado K. L. McNally D. J. Mackill 《Genetic Resources and Crop Evolution》2011,58(8):1237-1242
Submergence stress is a major constraint to rice production in South and Southeast Asia. Most rice (Oryza sativa L.) cultivars die within a week of complete submergence, while a small number of accessions are submergence-tolerant for up to
2 weeks or more. These cultivars have the tolerant allele of the SUB1A gene, one of three ERF genes at this locus on rice chromosome 9. In all O. sativa varieties studied, the SUB1A gene is limited to a subset of indica accessions of O. sativa. Thus far, there has been no published report of the SUB1A gene in wild rice species. Here we report evidence of the SUB1A gene found in wild species of O. rufipogon Griff. accessions by the use of degenerate primers corresponding to the most highly conserved regions of the SUB1 locus. The results indicated that two SUB1A-like alleles, e.g. OrSub1A-1 and OrSub1A-2, were identified from two O. rufipogon accessions. Submergence treatment shows that both of the accessions with SUB1A-like genes were submergence-intolerant. This preliminary study provides insight into the origin and allelic variation of
SUB1A, an agronomically important gene that is rapidly being introduced into widely-grown rice cultivars. 相似文献