共查询到20条相似文献，搜索用时 15 毫秒
1.
In this study, we report the mapping of the Rf locus in soybean by microsatellite simple sequence repeat (SSR) genetic markers. A cross was made between cytoplasmic male sterility (CMS) line JLCMS82A and restorer line JIHUI 1 based on the DNA polymorphisms revealed by 109 SSR markers. A F2 population derived from a single F1 plant containing 103 individuals was used for mapping the Rf locus. The Rf gene of JIHUI 1 gametophytically restores male fertility to JLCMS82A. Fertile and semi-fertile DNA bulks and parental DNAs were screened with 219 SSR markers, and Satt215 which was previously mapped to soybean LG J, was found linked to the Rf gene. Five additional polymorphic SSR markers from LG J were used for analysis and a regional linkage map around the Rf locus was established. SSR markers, Sctt011 and Satt547, flanked the Rf locus at 3.6 cM and 5.4 cM, respectively. The availability of these SSR markers will facilitate the selection of restorer lines in hybrid soybean breeding. 相似文献
2.
分子标记辅助选择聚合棉花Rf1育性恢复基因和抗虫Bt基因 总被引：19，自引：0，他引：19
胞质雄性不育恢复系0-613-2R与转Bt基因抗虫棉R019(轮回亲本)杂交、回交产生BC2群体。利用CMS恢复基因Rfl紧密连锁的3个SSR标记和Bt基因的PCR标记开展分子标记辅助选择培育聚合有Rfl和Bt的转基因抗虫棉恢复系。在分析的59个BC2单株中55株存在恢复基因标记，54株存在Bt基因；综合标记分析结果，共获得54个同时具Rfl与Bt基因的聚合单株；这些聚合单株自交后，通过标记辅助选择，获得10株含Bt基因且Rfl纯合的单株。为棉花优良恢复系的快速培育提供了重要基础。 相似文献
3.
AFLP-based STS markers closely linked to a fertility restoration locus (Rfm1) for cytoplasmic male sterility in barley 总被引：3，自引：0，他引：3
The Rfm1 gene restores the fertility of the msm1 and msm2 male‐sterile cytoplasms in barley. Rfm1 is located on the short arm of chromosome 6H. To develop molecular markers tightly linked to Rfm1 for use in sophisticated marker‐assisted selection and map‐based cloning, an amplified fragment‐length polymorphism (AFLP) marker system with isogenic lines and a segregating BC1F1 population was used. Nine hundred primer combinations were screened and a linkage map was constructed around the Rfm1 locus by using 25 recombinant plants selected from 214 BC1F1 plants. Three AFLP markers were identified, e34m2, e46m19 and e48m17, linked to the locus. The most closely linked markers were e34m2, at 1.0 cM distally and e46m19, at 1.1 cM proximally. The two AFLP markers were converted to dominant STS markers. These markers should accelerate programmes for breeding restorer lines and will be useful for map‐based cloning. 相似文献
4.
Powdery mildew (PM) can cause significant yield loss in mungbean and several loci conferring resistance to this disease have been identified. A restriction fragment length polymorphism (RFLP) marker (VrCS65) linked closely to one of these loci was used to screen a mungbean bacterial artificial chromosome (BAC) library and positive BAC clones identified were used to develop simple sequence repeat (SSR or microsatellite) and sequence tagged site (STS) markers. Four of the new PCR markers (including two SSRs and two STSs) co-segregated with the original RFLP marker VrCS65, and another SSR marker (VrCS SSR2) was located 0.5 cM away from it. These PCR-based and locus-specific markers could be useful in breeding cultivars with enhanced resistance to PM and in the further characterization of the locus including the isolation of gene(s) responsible for the resistance. 相似文献
5.
中国小麦LB0288中抗叶锈病基因的鉴定 总被引：2，自引：0，他引：2
明确中国小麦LB0288中所含的抗叶锈病基因,找到与其紧密连锁的DNA分子标记。将小麦LB0288和感病小麦品种Thatcher杂交,获得F1、F2代群体,用叶锈菌小FHTT分别对双亲及其杂交后代进行叶锈鉴定并进行标记分析。抗性鉴定结果表明F2代群体时呈现一对显性基因的抗感分离比例,经过亲本和抗感池间标记筛选以及F2代群体的标记检测,位于5DL的SSR标记barc144与抗病基因连锁,遗传距离为5.3 cM,同时Lr1的STS标记与之共分离,根据该基因的抗性特点和染色体位置推断为Lr1。此实验通过抗性鉴定、遗传分析和分子标记等手段确定LB0288中含有小麦抗叶锈病基因Lr1。 相似文献
6.
Two genic male sterile (GMS) lines, Lang-A conditioned by ms 15 and Zhongkang-A conditioned by ms 5 ms 6 duplicate recessive genes in Gossypium hirsutum L., were chosen to map GMS genes. These two lines were crossed with Gossypium barbadense cv. 'Hai7124' to produce segregating populations. The ms 15 gene was mapped on chromosome 12, and was flanked by two simple sequence repeat (SSR) markers, NAU2176 and NAU1278, with a genetic distance of 0.8 and 1.9 cM respectively. The ms 5 and ms 6 genes were mapped to one pair of homoeologous chromosomes, ms 5 on chromosome 12 flanked by three SSR markers, NAU3561, NAU2176 and NAU2096, with genetic distances of 1.4, 1.8 and 1.8 cM, respectively, and ms 6 on chromosome 26 flanked by two SSR markers, BNL1227 and NAU460, with a genetic distance of 1.4 and 1.7 cM respectively. These tightly linked markers with the ms 15 , ms 5 and ms 6 genes can be used in the marker-assisted selection among segregating populations in a breeding programme, and provide the foundation for gene isolation by map-based cloning for these three genes. 相似文献
7.
绿豆遗传连锁图谱的整合 总被引：3，自引：0，他引：3
利用绿豆及其近缘种的701对SSR引物,对现有绿豆遗传连锁图谱进行补充,结果在高感豆象绿豆栽培种Berken和高抗豆象绿豆野生种ACC41两亲本间筛选到多态性SSR引物104对。群体分析后,结合其他分子数据,使用作图软件Mapmaker/Exp 3.0b,获得一张含有179个遗传标记和12个连锁群,总长1831.8cM、平均图距10.2cM的新遗传连锁图谱,包括97个SSR标记,91个来自绿豆近缘种;RFLP标记76个;RAPD标记4个;STS标记2个。对32个绿豆、小豆共用SSR标记在遗传连锁图谱的分布分析发现,二个基因组间有一定程度的同源性,共用标记在连锁群上的排列顺序基本上一致,只有部分标记显示绿豆和小豆基因组在进化过程中发生了染色体重排;利用新图谱对ACC41的抗绿豆象主效基因重新定位,仍定位于I(9)连锁群,与其相邻分子标记的距离均小于8cM,其中与右翼SSR标记C220的距离约2.7cM。与原图谱比较,新定位的抗性基因与其相邻标记的连锁更加紧密。 相似文献
8.
芥菜型多室油菜的产量比普通两室油菜更高,定位乃至克隆多室基因可为油菜遗传改良及解释多室角果形成机制创造条件。本研究通过验证JD11-2家系衍生群体仅在BjMc2位点上存在差异,可用于BjMc2的定位。采用AFLP结合BSA法分析BC5和BC6群体,筛选到1个与BjMc2连锁的AFLP标记并转化为SCAR标记SC1。基于该AFLP标记序列信息,利用白菜同源序列设计SSR引物和SCAR引物,获得11对SSR标记和1对SCAR标记。通过在芥菜型油菜BAC文库中的挑选,获得2个覆盖目标区域的单克隆,由此开发1个SSR标记。将获得的SCAR和SSR标记扫描BC7群体,构建了两室性状基因BjMc2的遗传连锁图,两侧最近标记ZX17和BACsr96与目标基因之间的遗传距离分别为0.048 cM和0.340 cM,并定位到白菜A7 scaffold000019的946~1014 kb之间,约68 kb物理距离。 相似文献
9.
Fine mapping of Rf2, a major locus controlling pollen fertility restoration in sorghum A1 cytoplasm,encodes a PPR gene and its validation through expression analysis 
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下载免费PDF全文 Praveen Madugula Anurag G. Uttam Vilas A. Tonapi Madhusudhana Ragimasalawada 《Plant Breeding》2018,137(2):148-161
Sorghum is one of the pioneering cereal crops where cytoplasmic male sterility (CMS) was successfully exploited for mass production of F1 hybrid seed. Mapping genes for fertility restoration (Rf) is an important aspect of understanding the molecular basis of fertility restoration in crop plants. In this study, we fine‐mapped a fertility restoration locus, Rf2 of sorghum reported earlier (Jordan, Mace, Henzell, Klein, & Klein, 2010 ), involving two F2 populations (296A × RS29 and 296A × DSV1) and newly developed SSR markers delimited Rf2 locus to 10.32‐kb region on chromosome 2. The Rf2 locus was tightly linked with two new SSRs, MS‐SB02‐3460 (0.14 cM) and MS‐SB02‐3466 (0.75 cM) on both sides, and hosted only one gene (Sobic.002G057050) of PPR gene family. Another new SSR marker developed in the study, MS‐SB02‐37912, forms the part of PPR gene and could act as a perfect marker in marker‐assisted breeding for fertility restoration involving Rf2 in sorghum breeding. The strong involvement of Sobic.002G057050 gene in fertility restoration was supported through RNA expression analysis. 相似文献
10.
利用2个陆地棉种质材料爱字棉1517与德州047构建了重组近交系。田间调查显示,两亲本田间性状差异多数达到显著或极显著,群体性状数据完全符合受多位点控制的数量性状遗传的特征。分子标记多态性筛选结果表明,两亲本亲缘关系相对较近,利用SSR构建高密度遗传连锁图有一定困难,但对于所定位的QTL位点,其准确性将会有一定程度提高。试验构建了一张包括51个标记分为15个连锁群的遗传连锁图,总长504.05 cM,覆盖棉花基因组总长度的10.08%。利用两年田间数据检测到QTL位点15个,其中生育期性状3个,纤维品质性状7个,产量性状5个。与标记图距在1 cM以内的QTL位点7个,这将对分子标记辅助育种具有一定的参考价值。 相似文献
11.
The use of the new cytoplasmic male sterility (CMS) source PEF1 in sunflower hybrid breeding requires markers closely linked to the restorer gene Rf_PEF1 necessary for fertility restoration of hybrids based on the PEF1 cytoplasm as well as diagnostic markers to distinguish the PEF1 cytoplasm from other cytoplasms. Bulked segregant analyses of 256 AFLP primer combinations identified 35 polymorphic primer combinations with 1–3 polymorphisms, resulting in 40 polymorphisms. Eighteen AFLP markers mapped together with the Rf_PEF1 gene covering 119.9 cM. The closest markers, E39M51_300R and E44M56_112A, mapped 3.9 and 6.0 cM to the Rf_PEF1 gene, respectively. Six SSR markers, which belong to the linkage group 13, were screened for polymorphisms between the parental lines. Only ORS630 was polymorphic, but did not map to the same linkage group as Rf_PEF1, indicating that Rf_PEF1 is not located on linkage group 13 where the restorer gene Rf1 for the PET1 cytoplasm is located. Diagnostic markers to distinguish the PEF1 cytoplasm from the PET1 and the fertile cytoplasm in sunflower were obtained using primer combinations for the atp9 gene and orfH522. 相似文献
12.
L. Bazrkar A. J. Ali N. A. Babaeian A. A. Ebadi M. Allahgholipour K. Kazemitabar G. Nematzadeh 《Euphytica》2008,164(3):669-677
Tagging of restorer genes for wild abortive (WA) CMS source by studying a 222 individual plants from a F2 population of a cross between IR58025A × IR42686R. The restorer line IR42686R that was used in this study had been previously
derived through random mating composite population (RMCP) involving 12 parents facilitated by IR36 genetic male sterility.
Four Rf genes were tagged to simple sequence repeats (SSR) markers on chromosomes 1, 7, 10, 12 by recessive class analysis. The recombination
frequency between a positive marker and Rf locus was calculated using maximum likelihood estimator assuming that all the 46 extremely sterile individual plants were
homozygous at the targeted Rf locus. The recombination frequency between the marker and the restorer trait were converted to genetic distances using Kosambi
function. A new Rf locus designated as Rf7 on chromosome 12 was found to be linked to RM7003 at a genetic distance of 13.3 cM (LOD 6.12). We report here first, a new
molecular marker (RM 6344) linked to Rf4 locus on chromosome 7 that was previously mapped by trisomic analysis. RM443 and RM315 were flanking the Rf3 gene at a genetic distance of 4.4 (LOD 10.29) and 20.7 cM (LOD 3.98) on chromosome 1, respectively. The Rf6 was flanked on both side with SSR markers RM258 and RM591 at a genetic distance of 4.4 (LOD 10.29) and 23.3 cM (LOD 3.39)
located on chromosome 10. The random mating composite population is an excellent breeding approach to develop superior restorer
lines and for pyramiding different Rf genes of different CMS systems. Rf genes tagged with closely linked SSR markers would be facilitating marker assisted selection
(MAS) in hybrid rice breeding program by reducing time and workload for identifying potential restorers.
L. Bazrkar and A. J. Ali equally contributed to this work. 相似文献
13.
Heterosis is an important way to improve yield and quality for many crops. Hybrid rice and hybrid maize contributed to enhanced productivity which is essential to supply enough food for the increasing world population. The success of hybrid rice in China has led to a continuous interest in hybrid wheat, even when most research on hybrid wheat has been discontinued in other countries for various reasons including low heterosis and high seed production costs. The Timopheevii cytoplasmic male sterile system is ideal for producing hybrid wheat seeds when fertility restoration lines with strong fertility restoration ability are available. To develop PCR-based molecular markers for use in marker-assisted selection of fertility restorer lines, two F2 populations derived from crosses R18/ND36 and R9034/ND36 were used to map fertility restoration genes in the two elite fertility restorer lines (R-lines) R18 and R9034. Over 678 SSR markers were analyzed, and markers closely linked to fertility restoration genes were identified. Using SSR markers, a major fertility restoration gene, Rf3, was located on the 1B chromosome in both populations. This gene was partially dominant in conferring fertility restoration in the two restorer lines. SSR markers Xbarc207, Xgwm131, and Xbarc61 are close to this gene. These markers may be useful in marker-assisted selection of new restorer lines with T. timopheevii cytoplasm. Two minor QTL conferring fertility restoration were also identified on chromosomes 5A (in R18) and 7D (in R9034) in two R-lines. 相似文献
14.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most devastating diseases in common wheat ( Triticum aestivum L.). With the objective of identifying and tagging a new gene for resistance to stripe rust in wheat line P81, F1 , F2 and F2:3 populations from the cross 'Chuanmai 28'/P81 were inoculated with Chinese PST race CYR32 in greenhouse and field trials. P81 carried a single dominant gene for resistance (designated YrP81 ) to CYR32. Tests of allelism showed that YrP81 was different from Yr5 , Yr10 , Yr15 and Yr26 . Simple sequence repeat (SSR) and resistance gene-analogue polymorphism (RGAP) between the parents were used for genotyping the F2 populations. YrP81 was closely linked to four SSR loci on chromosome 2BS with genetic distances of 18.3 cM ( Xwmc25 ), 1.8 cM ( Xgwm429 ), 4.1 cM ( Xwmc770 ) and 5.3 cM ( Xgwm148 ). Two RGAP markers RGA1 (NLRR/XLRR) and RGA2 (Pto kin4/NLRR-INV2) were also closely linked to YrP81 with genetic distances of 4.7 and 6.3 cM, respectively. The linkage map of YrP81 and molecular markers was established in the order Xwmc25 - RGA2 - RGA1 - Xgwm429 - YrP81 - Xwmc770 - Xgwm148 . Pedigree analysis, response patterns with Chinese PST races and associations with markers suggested that YrP81 is a novel stripe rust resistance gene. The PCR-based microsatellite and RGAP markers identified here could be applied in selection of YrP81 in wheat breeding. 相似文献
15.
Soon Jae Kwon Petr Smýkal Jinguo Hu Meinan Wang Sung‐Jin Kim Rebecca J. McGee Kevin McPhee Clarice J. Coyne 《Plant Breeding》2013,132(6):642-648
Fusarium wilt is one of the most widespread diseases of pea. Resistance to Fusarium wilt race 1 was reported as a single gene, Fw, located on linkage group III. The previously reported AFLP and RAPD markers linked to Fw have limited usage in marker‐assisted selection due to their map distance and linkage phase. Using 80 F8 recombinant inbred lines (RILs) derived from the cross of Green Arrow × PI 179449, we amplified 72 polymorphic markers between resistant and susceptible lines with the target region amplified polymorphism (TRAP) technique. Marker–trait association analysis revealed a significant association. Five candidate markers were identified and three were converted into user‐friendly dominant SCAR markers. Forty‐eight pea cultivars with known resistant or susceptible phenotypes to Fusarium wilt race 1 verified the marker–trait association. These three markers, Fw_Trap_480, Fw_Trap_340 and Fw_Trap_220, are tightly linked to and only 1.2 cM away from the Fw locus and are therefore ideal for marker‐assisted selection. These newly identified markers are useful to assist in the isolation of the Fusarium wilt race 1 resistance gene in pea. 相似文献
16.
N. K. Sheeba B. C. Viraktamath S. Sivaramakrishnan M. G. Gangashetti Pawan Khera R. M. Sundaram 《Euphytica》2009,167(2):217-227
The present study was carried out with the objective to validate the molecular markers, which have been previously reported
to be linked to fertility restorer (Rf) gene(s) for WA-CMS lines of rice. Two mapping populations involving fertility restorer lines for WA-cytoplasm, viz., (i)
an F2 population derived from the cross IR58025A/KMR3R consisting of 347 plants and (ii) a BC1F1 population derived from the cross IR62829A/IR10198R//IR62829A consisting of 130 plants were analyzed. Nine SSR and three
CAPS markers reported to be linked to Rf genes along with two previously unreported SSR markers were analyzed in the mapping populations. In both the populations
studied, the trait of fertility restoration was observed to be under digenic control. Eight SSR markers (RM6100, RM228, RM171,
RM216, RM474, RM311, MRG4456 and pRf1&2) showed polymorphism between the parents of the F2 population, while the SSR markers RM6100 and RM474 showed polymorphism between the parents of both the F2 and BC1F1 populations. Only one CAPS marker, RG146FL/RL was polymorphic between the parents of the BC1F1 population. RM6100 was observed to be closely segregating with fertility restoration in both the mapping populations and
was located at a distance of ~1.2 cM. The largest phenotypic variation was accounted for the region located between RM311
and RM6100. Using the marker-trait segregation data derived from analysis of both the mapping populations, a local linkage
map of the genomic region around Rf-4, a major fertility restoration locus on Chromosome 10 was constructed, and RM6100 was observed to be very close to the gene
at a distance of 1.2 cM. The accuracy of the marker RM6100 in predicting fertility restoration was validated in 21 restorers
and 18 maintainers. RM6100 amplified the Rf-4 linked allele in a majority of the restorers with a selection accuracy of 94.87%. Through the present study, we have established
the usefulness of the marker RM6100 in marker-assisted selection for fertility restoration in segregating populations and
identification of restorers while screening rice germplasm for their fertility restoration ability. 相似文献
17.
Myung Sik Kim Min Jung Park Woo Hyeun Jeong Ki Chul Nam Jong Il Chung 《Euphytica》2006,152(3):361-366
Soybean is a major source of protein meal in the world. Soybean kunitz trypsin inhibitor (SKTI) protein is a responsible for the inferior nutritional quality of unheated or incompletely heated soybean meal. The primary objective of this research was to identify DNA markers linked to the Ti locus controlling presence and absence of kunitz trypsin inhibitor protein. Two mapping populations were developed. Population 1 was derived from a cross between cultivar Jinpumkong2 (TiTi) and C242 (titi). Population 2 was made from a mating between cultivar Clark (TiTi) and C242. The F1 plants were grown in the greenhouse to produce F2 seeds. Each F2 seed from F1 plants was analyzed electrophoretically to determine the presence of the SKTI protein band. One-thousand RAPD primers, 342 AFLP primer sets, and 35 SSR primers were used to map Ti locus in population 1 and 2. The presence of SKTI protein was dominant to the lack of a SKTI protein and kunitz trypsin inhibit protein band was controlled by a single locus. Twelve DNA markers (4 RAPD, 4 AFLP, and 3 SSR) and Ti locus were found to be genetically linked in population 1 consisted with 94 F2 individual plants. Three SSR markers (Satt409, Satt228, and Satt429) were linked with Ti locus within 10 cM. Satt228 marker was tightly linked with Ti locus. Satt228 marker was tightly linked within 0–3.7 cM of the Ti locus and may be useful in a marker assisted selection program. 相似文献
18.
Molecular mapping of the fertility-restoration gene Rf4 for WA-cytoplasmic male sterility in rice 总被引：4，自引：0，他引：4
The wild abortive cytoplasmic male sterility (CMS‐WA) system, an ideal type of sporophytic CMS in indica rice, is used for the large‐scale commercial production of hybrid rice. Searching for restorer genes is a good approach when phenotyping is very time‐consuming and requires the determination of spikelet sterility in testcross progeny. To establish more precisely the genetical and physical maps of the Rf4 gene, high‐resolution mapping of this locus was carried out using simple sequence repeat (SSR) markers and newly designed markers in a F2 population. The genetic linkage analysis indicated that five SSR markers (RM6737, RM304, RM171, RM5841 and RM228) on the long arm of chromosome 10 were linked with the Rf4 gene. Rf4 was flanked by two SSR markers RM171 and RM6737 at distances of 3.2 and 1.6 cM, respectively. Also, within the region between Rf4 gene and RM171, a newly designed primer pair, AB443, produced two sterile‐specific markers, AB443‐400 and AB443‐500, 0.5 and 1.03 cM from the gene. The flanking markers identified give promise for their application in molecular marker‐assisted selection (MAS) and they are also suitable for starting chromosome walking to clone Rf4 gene in the near future. 相似文献
19.
Virginia Menzo Angelica Giancaspro Stefania Giove Domenica Nigro Silvana Zacheo Pasqualina Colasuonno Ilaria Marcotuli Ornella Incerti Antonio Blanco Agata Gadaleta 《Euphytica》2013,194(2):151-160
Target region amplification polymorphism (TRAP) is a relatively new PCR-based technique that detects large numbers of loci in a single reaction without extensive pre-PCR processing of samples. The aim of this study was to integrate TRAP markers in an EST-derived SSR linkage map of a RIL mapping population from the cross of the durum wheat cultivars Ciccio and Svevo, for a more general purpose of establishing a high-throughput system for genetic map saturation. Primer combinations producing PCR products with at least 4–5 polymorphic bands were selected and analyzed across the mapping population. The PCR reactions produced a total of 2,881 fragments with an average of 52 peaks per reaction. A total of 142 new TRAP markers were mapped and found to be randomly distributed in the genome. The total length of the map was 2,043.0 cM, with an average chromosome length of 145.9 cM. Homoeologous group one had the highest number of TRAP markers (38 loci) and the longest map length (407.9 cM) for a total of 87 markers, while the homoeologous group five had the lowest TRAP marker number (5 loci) and the shortest map length (232.5 cM). The distribution of markers among the seven homoeologous groups was random. The results indicate that TRAP is highly efficient in genetic mapping, generating a large number of markers scattered across the genome. This closes many existing gaps in marker coverage and may join otherwise separate linkage groups. 相似文献
20.
Genetic study on important traits of tea is difficult because of its self-incompatibility in nature. Moreover, development of a new variety usually needs more than 20 years, since it takes many years from seedling to matured plants for trait investigation. Genetic map is an essential tool for genetic study and breeding. In this study, we have developed an integrated genetic map of tea (Camellia sinensis) using a segregating F1 population derived from a cross between two commercial cultivars (‘TTES 19’ and ‘TTES 8’). A total of 574 polymorphic markers (including SSR, CAPS, STS, AFLP, ISSR and RAPD), 69 markers with highly significant levels of segregation distortion (P < 0.001) (12.0 %) were excluded from further analyses. Of the 505 mapped markers, there were 265 paternal markers (52.5 %), 163 maternal markers (32.3 %), 65 doubly heterozygous dominant markers (12.9 %), and 12 co-dominant markers (2.4 %). The co-dominant markers and doubly heterozygous dominant markers were used as bridge loci for the integration of the paternal and maternal maps. The integrated map comprised 367 linked markers, including 36 SSR, 3 CAPS, 1 STS, 250 AFLP, 13 ISSR and 64 RAPD that were assigned to 18 linkage groups. The linkage groups represented a total map length of 4482.9 cM with a map density of 12.2 cM. This genetic map has the highest genetic coverage so far, which could be applied to comparative mapping, QTL mapping and marker assisted selection in the future. 相似文献