共查询到20条相似文献,搜索用时 15 毫秒
1.
V. Chagué J. C. Mercier M. Guénard A. de Courcel F. Vedel 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(8):1045-1051
Bulked segregant analysis was used to identify random amplified polymorphic DNA (RAPD) markers linked to the Sw-5 gene for resistance to tomato spotted wilt virus (TSWV) in tomato. Using two pools of phenotyped individuals from one segregating population, we identified four RAPD markers linked to the gene of interest. Two of these appeared tightly linked to Sw-5, whereas another, linked in repulsion phase, enabled the identification of heterozygous and susceptible plants. After linkage analysis of an F2 population, the RAPD markers were shown to be linked to Sw-5 within a distance of 10.5 cM. One of the RAPD markers close to Sw-5 was used to develop a SCAR (sequence characterized amplified region) marker. Another RAPD marker was stabilized into a pseudo-SCAR marker by enhancing the specificity of its primer sequence without cloning and sequencing. RAPD markers were mapped to chromosome 9 on the RFLP tomato map developed by Tanksley et al. (1992). The analysis of 13 F3 families and eight BC2 populations segregating for resistance to TSWV confirmed the linkage of the RAPD markers found. These markers are presently being used in marker-assisted plant breeding. 相似文献
2.
Identification of RAPD markers linked to the gene PM 1 for resistance to powdery mildew in wheat 总被引:17,自引:0,他引:17
X. Y. Hu H. W. Ohm I. Dweikat 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(6-7):832-840
Powdery mildew caused by Blumeria graminis DC. f. sp. triticiém. Marchal is an important disease of wheat (Triticum aestivum L. em Thell). We report here the identification of three random amplified polymorphic DNA (RAPD) markers closely linked to
a gene for resistance to B. graminis in wheat. RAPD-PCR (polymerase chain reaction) analysis was conducted using bulked segregant analysis of closely related
lines developed from a segregating F5 family. The F5 family was derived from a cross between the susceptible cultivar Clark and the resistant line Zhengzhou 871124. Genetic analysis
indicated that resistance of Zhengzhou 871124 to powdery mildew is conferred by the gene Pm1. After performing RAPD-PCR analysis with 1300 arbitrary 10-mer primers and agarose-gel electrophoresis, two RAPD markers,
UBC320420 and UBC638550, were identified to be co-segregating with the disease resistance. No recombinants were observed between either of the RAPD
markers and the gene for resistance to powdery mildew after analysis of 244 F2 plants. The third RAPD marker, OPF12650, was identified with denaturing gradient-gel electrophoresis (DGGE), and was determined to be 5.4±1.9 cM from the resistance
gene. UBC320420 and UBC638550 were present in wheat powdery mildew differential lines carrying the gene Pm1, suggesting linkage between these markers and the Pm1 resistance gene. Co-segregation between Pm1 and the two markers UBC320420 and UBC638550 was confirmed in a segregating population derived from a cross with CI14114, the wheat differential line carrying Pm1. The method of deriving closely related lines from inbred families that are segregating for a trait of interest should find
wide application in the identification of DNA markers linked to important plant genes. The RAPD marker UBC638550 was converted to a sequence tagged site (STS). RAPD markers tightly linked to target genes may facilitate selection and enable
gene pyramiding for powdery mildew resistance in wheat breeding programs.
Received: 10 December 1995 / Accepted: 13 September 1996 相似文献
3.
Identification and validation of molecular markers linked to the leaf rust resistance gene Lr19 in wheat 总被引:2,自引:0,他引:2
Gupta SK Charpe A Prabhu KV Haque QM 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,113(6):1027-1036
A leaf rust resistance gene Lr19 on the chromosome 7DL of wheat derived from Agropyron elongatum was tagged with random amplified polymorphic DNA (RAPD) and microsatellite markers. The F2 population of 340 plants derived from a cross between the leaf rust resistant near-isogenic line (NIL) of Thatcher (Tc + Lr19) and leaf rust susceptible line Agra Local that segregated for dominant monogenic leaf rust resistance was utilized for generating the mapping population. The molecular markers were mapped in the F2 derived F3 homozygous population of 140 seedlings. Sixteen RAPD markers were identified as linked to the alien gene Lr19 among which eight were in a coupling phase linkage. Twelve RAPD markers co-segregated with Lr19 locus. Nine microsatellite markers located on the long arm of chromosome 7D were also mapped as linked to the gene Lr19, including 7 markers which co-segregated with Lr19 locus, thus generating a saturated region carrying 25 molecular markers linked to the gene Lr19 within 10.2 ± 0.062 cM on either side of the locus. Two RAPD markers S265512 and S253737 which flanked the locus Lr19 were converted to sequence characterized amplified region markers SCS265512 and SCS253736, respectively. The marker SCS265512 was linked with Lr19 in a coupling phase and the marker SCS253736 was linked in a repulsion phase, which when used together mimicked one co-dominant marker capable of distinguishing the heterozygous resistant seedlings from the homozygous resistant. The molecular markers were validated on NILs mostly in Thatcher background isogenic for 44 different Lr genes belonging to both native and alien origin. The validation for polymorphism in common leaf rust susceptible cultivars also confirmed the utility of these tightly linked markers to the gene Lr19 in marker-assisted selection. 相似文献
4.
利用RAPD(Random amplified polymorphic DNA)分子标记技术,寻找谭清苏铁(Cycas tanqingii)中与性别相关的分子标记,筛选了160个10bp的随机引物,产生了2500多个RAPD条带。只有引物S0465 (CCCCGGTAAC)产生了一条大约500bp的雌性特异RAPD标记,该分子标记出现在所有的供试雌性植株中,而所有的供试雄性植株都不具有该标记。对该特异片段进行了克隆和序列测定,并根据序列分析结果将RAPD标记转化为重复性和特异性更好的特异特征序列扩增区域(SCAR)分子标记,并命名为STQC-S465-483。分子标记的建立可用于谭清苏铁幼苗性别的早期鉴定,为谭清苏铁就地保护和迁地保护提供技术支持。 相似文献
5.
Three interspecific crosses were developed using Cicer arietinum (ICC 4918) as the female parent and wild Cicer species [C. reticulatum - JM 2100, JM 2106 and C. echinospermum - ICCW 44] as the male parent. Cicer arietinum (ICC 4918) × C. reticulatum (JM 2100) cross produced the largest number of F2 plants and was chosen for linkage mapping using Random Amplified Polymorphic DNA (RAPD) primers. A partial linkage map was constructed based upon the segregation of 36 RAPD markers obtained by amplification using 35 primers. The linkage map consists of two linkage groups with 17 linked markers covering a total of 464.9 cM. Analyses also revealed association of three morphological traits with linked RAPD markers. Out of seven morphological traits tested for association with linked markers in the segregating plants, four Quantitative trait loci (QTL) were detected for the trait leaf length and three QTLs each for the traits leaf width and erect plant habit. 相似文献
6.
A major locus for submergence tolerance mapped on rice chromosome 9 总被引:18,自引:0,他引:18
Kenong Xu David J. Mackill 《Molecular breeding : new strategies in plant improvement》1996,2(3):219-224
Submergence stress is a widespread problem in rice-growing environments where drainage is impeded. A few cultivars can tolerate more than 10 days of submergence, but the genes conferring this tolerance have not been identified. We used randon-amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers to map submergence tolerance in 169 F2 plants and the resulting F3 families of a cross between a tolerant indica rice line, IR40931-26, and a susceptible japonica line, PI543851. IR40931-26 inherited strong submergence tolerance from the unimproved cultivar FR13A. Eight-day old F3 seedlings were submerged for 14–16 days in 55-cm deep tanks, and tolerance was scored after 7 days recovery on a scale of 1 (tolerant) to 9 (susceptible). The tolerant and susceptible parents scored 1.5 and 8.4, respectively, and the F3 means ranged from 1.6 to 8.9. Two bulks were formed with DNA from F2 plants corresponding to the nine most tolerant and the nine most susceptible F3 families. Of 624 RAPD primers used to screen the bulks, five produced bands associated with either tolerance or susceptibility. These markers were mapped to a region of chromosome 9 by linkage to RFLP markers. A submergence tolerance quantitative trait locus (QTL), here designatedSub1, was located ca. 4 cM from the RFLP marker C1232 and accounted for 69% of the phenotypic variance for the trait. 相似文献
7.
Development of RAPD and SCAR markers linked to the Russian wheat aphid resistance gene Dn2 in wheat 总被引:5,自引:0,他引:5
A. A. Myburg M. Cawood B. D. Wingfield A.-M. Botha 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(8):1162-1169
RAPD (random amplified polymorphic DNA) analysis was used to identify molecular markers linked to the Dn2 gene conferring resistance to the Russian wheat aphid (Diuraphis noxia Mordvilko). A set of near-isogenic lines (NILs) was screened with 300 RAPD primers for polymorphisms linked to the Dn2 gene. A total of 2700 RAPD loci were screened for linkage to the resistance locus. Four polymorphic RAPD fragments, two in
coupling phase and two in repulsion phase, were identified as putative RAPD markers for the Dn2 gene. Segregation analysis of these markers in an F2 population segregating for the resistance gene revealed that all four markers were closely linked to the Dn2 locus. Linkage distances ranged from 3.3 cM to 4.4 cM. Southern analysis of the RAPD products using the cloned RAPD markers
as probes confirmed the homology of the RAPD amplification products. The coupling-phase marker OPB10880c and the repulsion-phase marker OPN1400r were converted to sequence characterized amplified region (SCAR) markers. SCAR analysis of the F2 population and other resistant and susceptible South African wheat cultivars corroborated the observed linkage of the RAPD
markers to the Dn2 resistance locus. These markers will be useful for marker-assisted selection of the Dn2 gene for resistance breeding and gene pyramiding.
Received: 1 July 1997 / Accepted: 20 October 1997 相似文献
8.
Singh M Chaudhary K Boora KS 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,114(1):187-192
Anthracnose, caused by Colletotrichum graminicola, infects all aerial parts of sorghum, Sorghum bicolor (L.) Moench, plants and causes loss of as much as 70%. F1 and F2 plants inoculated with local isolates of C. graminicola indicated that resistance to anthracnose in sorghum accession G 73 segregated as a recessive trait in a cross with susceptible cultivar HC 136. To facilitate the use of marker-assisted selection in sorghum breeding programs, a PCR-based specific sequence characterized amplified region (SCAR) marker was developed. A total of 29 resistant and 20 susceptible recombinant inbred lines (RILs) derived from a HC 136 × G 73 cross was used for bulked segregant analysis to identify a RAPD marker closely linked to a gene for resistance to anthracnose. The polymorphism between the parents HC 136 and G 73 was evaluated using 84 random sequence decamer primers. Among these, only 24 primers generated polymorphism. On bulked segregant analysis, primer OPA 12 amplified a unique band of 383 bp only in the resistant parent G 73 and resistant bulk. Segregation analysis of individual RILs showed the marker OPA 12383 was 6.03 cM from the locus governing resistance to anthracnose. The marker OPA 12383 was cloned and sequenced. Based on the sequence of cloned RAPD product, a pair of SCAR markers SCA 12-1 and SCA 12-2 was designed using the MacVector program, which specifically amplified this RAPD fragment in resistant parent G 73, resistant bulk and respective RILs. Therefore, it was confirmed that SCAR marker SCA 12 is at the same locus as RAPD marker OPA 12383 and hence, is linked to the gene for resistance to anthracnose. 相似文献
9.
Yamen A. S. Hamdan Leonardo Velasco Begoña Pérez-Vich 《Molecular breeding : new strategies in plant improvement》2008,22(3):385-393
Practically no molecular tools have been developed so far for safflower (Carthamus tinctorius L.) breeding. The objective of the present research was to develop molecular markers for the closely linked genes Li, controlling very high linoleic acid content, and Ms, controlling nuclear male sterility (NMS). A mapping population of 162 individuals was developed from the NMS line CL1 (64–79%
linoleic acid) and the line CR-142 (84–90%), and phenotyped in the F2 and F3 generations. Bulked segregant analysis with random amplified polymorphic (RAPD) markers revealed linkage of five RAPD bands
to the Li and Ms genes. RAPD fragments were converted into sequence-characterized amplified region (SCAR) markers. A linkage map including
the five SCAR markers and the Li and Ms genes was constructed. SCAR markers flanked both loci at minimum distances of 15.7 cM from the Li locus and 3.7 cM from the Ms locus. These are the first molecular markers developed for trait selection in safflower. 相似文献
10.
Tanhuanpää P 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(6):1039-1046
The objective of this investigation was to tag a locus for white rust resistance in a Brassica rapa ssp. oleifera F2 population segregating for this trait, using bulked segregant analysis with random amplified polymorphic DNA (RAPD) markers, linkage mapping and a candidate gene approach based on resistance gene analogs (RGAs). The resistance source was the Finnish line Bor4109. The reaction against white rust races 7a and 7v was scored in 20 seedlings from each self-pollinated F2 individual. The proportion of resistant plants among these F3 families varied from 0 to 67%. Bulked segregant analysis did not reveal any markers linked with resistance and, therefore, a linkage map with 81 markers was created. A locus that accounted for 18.4% of the variation in resistance to white rust was mapped to linkage group (LG) 2 near the RAPD marker Z19a. During the study, a bacterial resistance gene homologous to Arabidopsis RPS2 and six different RGAs were sequenced. RPS2 and five of the RGAs were mapped to linkage groups LG1, LG4 and LG9. Unfortunately, none of the RGAs could be shown to be associated with white rust resistance.Communicated by H.C. BeckerThe nucleotide sequence data reported has been deposited in the Genbank under the accession numbers AF315081–AF315087. 相似文献
11.
Fuli Liu Jianting Yao Xiuliang Wang Zimin Hu Delin Duan 《Journal of applied phycology》2011,23(4):709-713
To construct a molecular-marker-assisted selection (MAS) system, research was done on identifying molecular markers linking
to longer frond length, a crucial selection index in the breeding of the commercially important seaweed Saccharina japonica. An F2-segregant population of 92 individuals was obtained by crossing two prominent S. japonica strains. Genomic DNA from ten individuals with the longest frond and ten individuals with the shortest frond in the F2-segregant population were mixed to create two DNA pools for screening polymorphic markers. In bulked-segregant analysis (BSA),
out of 100 random amplified polymorphic DNA (RAPD) primers only two produced three polymorphic RAPD markers between the two
DNA pools. In conversion of the three RAPD markers into sequence-characterized amplified region (SCAR) markers, only one was
successfully converted into a SCAR marker FL-569 linking to the trait of longer frond. Test of the marker FL-569 showed that
80% of the individuals with longest fronds in a wild population and 87.5% of individuals with the longest fronds in an inbred
line “Zhongke No. 2” could be detected by FL-569. Additionally, genetic linkage analysis showed that the SCAR marker could
be integrated into the reported genetic map and QTL mapping showed that FL-569 linking to qL1-1. The obtained marker FL-569
will be beneficial to MAS in S. japonica breeding. 相似文献
12.
Identification and application of RAPD markers for anthracnose resistance in water yam (Dioscorea alata) 总被引:1,自引:0,他引:1
Anthracnose, caused by Colletotrichum gloeosporioides, is the most severe foliar disease of water yam (Dioscorea alata) worldwide. The tetraploid breeding line, TDa 95/00328, is a source of dominant genetic resistance to the moderately virulent fast growing salmon (FGS) strain of C. gloeosporioides. Bulked segregant analysis was used to search for random amplified polymorphic DNA (RAPD) markers linked to anthracnose resistance in F1 progeny derived from a cross between TDa 95/00328 and the susceptible male parent, TDa 95–310. Two hundred and eighty decamer primers were screened using bulks obtained from pooled DNA of individuals comprising each extreme of the disease phenotype distribution. A single locus that contributes to anthracnose resistance in TDa 95/00328 was identified and tentatively named Dcg‐1. We found two RAPD markers closely linked in coupling phase with Dcg‐1, named OPI71700 and OPE6950, both of which were mapped on the same linkage group. OPI71700 appeared tightly linked to the Dcg‐1 locus; it was present in all the 58 resistant F1 individuals and absent in all but one of the 13 susceptible genotypes (genetic distance of 2.3 cM). OPE6950 was present in 56 of the 58 resistant progeny and only one susceptible F1 plant showed this marker (6.8 cM). Both markers successfully identified Dcg‐1 in resistant D. alata genotypes among 34 breeding lines, indicating their potential for use in marker‐assisted selection. OPI71700 and OPE6950 are the first DNA markers for yam anthracnose resistance. The use of molecular markers presents a valuable strategy for selection and pyramiding of anthracnose resistance genes in yam improvement. 相似文献
13.
L. J. Rowland A. Levi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,87(7):863-868
An initial genetic linkage map for blueberry has been constructed from over 70 random amplified polymorphic DNA (RAPD) markers that segregated 11 in a testcross population of 38 plants. The mapping population was derived from a cross between two diploid blueberry plants: the F1 interspecific hybrid (Vaccinium darrowi Camp x V. elliottii Chapm.) and another V. darrowi plant. The map currently comprises 12 linkage groups (in agreement with the basic blueberry chromosome number) and covers a total genetic distance of over 950cM, with a range of 3–30cM between adjacent markers. The use of such a map for identifying molecular markers linked to genes controlling chilling requirement and cold hardiness is discussed. 相似文献
14.
Yang DE Jin DM Wang B Zhang DS Nguyen HT Zhang CL Chen SJ 《Molecular genetics and genomics : MGG》2005,274(3):229-234
The maize inbred lines 1145 (resistant) and Y331 (susceptible), and the F1, F2 and BC1F1 populations derived from them were inoculated with the pathogen Pythium inflatum Matthews, which causes stalk rot in Zea mays. Field data revealed that the ratio of resistant to susceptible plants was 3:1 in the F2 population, and 1:1 in the BC1F1population, indicating that the resistance to P. inflatum Matthews was controlled by a single dominant gene in the 1145×Y331 cross. The gene that confers resistance to P. inflatum Matthews was designated Rpi1 for resistance to P. inflatum) according to the standard nomenclature for plant disease resistance genes. Fifty SSR markers from 10 chromosomes were first
screened in the F2 population to find markers linked to the Rpi1 gene. The results indicated that umc1702 and mmc0371 were both linked to Rpi1, placing the resistance gene on chromosome 4. RAPD (randomly amplified polymorphic DNA) markers were then tested in the F2population using bulked segregant analysis (BSA). Four RAPD products were found to show linkage to the Rpi1 gene. Then 27 SSR markers and 8 RFLP markers in the region encompassing Rpi1 were used for fine-scale mapping of the resistance gene. Two SSR markers and four RFLP markers were linked to the Rpi1 gene. Finally, the Rpi1 gene was mapped between the SSR markers bnlg1937 and agrr286 on chromosome 4, 1.6 cM away from the former and 4.1 cM distant
from the latter. This is the first time that a dominant gene for resistance to maize stalk rot caused by P. inflatum Matthews has been mapped with molecular marker techniques. 相似文献
15.
Y. H. Lu J. M. Melero-Vara J. A. García-Tejada P. Blanchard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):625-632
A consensus molecular linkage map of 61.9 cM containing the Or5 gene, which confers resistance to race E of broomrape orobanche cumana, five SCAR markers (three dominant, two codominant) and one RAPD marker were identified based on segregation data scored
from two F2 populations of susceptible×resistant sunflower line crosses. Bulked segregant analysis was carried out to generate the five
SCAR markers, while the single RAPD marker in the group was identified from 61 segregating RAPD markers that were directly
screened on one of the two F2 populations. The five SCAR markers, RTS05, RTS28, RTS40, RTS29 and RTS41, were significantly (LOD≥4.0) linked to the Or5 gene and mapped separately at 5.6, 13.6, 14.1, 21.4 and 39.4 cM from the Or5 locus on one side, while the RAPD marker, UBC120_660, was found at 22.5 cM (LOD=1.4) on the opposite side. These markers
should facilitate the efficient transfer of the resistance gene among sunflower breeding lines. As the first report on molecular
markers linked to a broomrape resistance gene, the present work provides a starting point to study other genes and to examine
the hypothesis of the clustering of broomrape resistance genes in sunflower.
Received: 16 September 1998 / Accepted: 22 June 1999 相似文献
16.
S. K. Naess J. M. Bradeen S. M. Wielgus G. T. Haberlach J. M. McGrath J. P. Helgeson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(5-6):697-704
Somatic hybrids between potato and Solanum bulbocastanum, a wild diploid (2n=2x=24) Mexican species, are highly resistant to late blight, caused by Phytophthora infestans. Both randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers that are closely
linked to the resistance have been noted by analysis of three different backcross-2 populations derived from two different
somatic hybrids. With reference to previously published potato and tomato maps, resistance appears to be on the long arm of
chromosome 8 and is flanked by RFLP markers CP53 and CT64. In a population of BC2 plants derived from a cross between the BC1 line J10lK6 [(S. tuberosum PI 203900+S. bulbocastanum PI 243510) ×Katahdin)]×Atlantic, late blight resistance cosegregated with RFLP marker CT88 and RAPD marker OPG02–625.
Received: 26 November 1999 / Accepted: 22 December 1999 相似文献
17.
Narasimhamoorthy B Bouton JH Olsen KM Sledge MK 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(5):901-913
Aluminum (Al) toxicity in acid soils is a major limitation to the production of alfalfa (Medicago sativa subsp. sativa L.) in the USA. Developing Al-tolerant alfalfa cultivars is one approach to overcome this constraint. Accessions of wild
diploid alfalfa (M. sativa subsp. coerulea) have been found to be a source of useful genes for Al tolerance. Previously, two genomic regions associated with Al tolerance
were identified in this diploid species using restriction fragment length polymorphism (RFLP) markers and single marker analysis.
This study was conducted to identify additional Al-tolerance quantitative trait loci (QTLs); to identify simple sequence repeat
(SSR) markers that flank the previously identified QTLs; to map candidate genes associated with Al tolerance from other plant
species; and to test for co-localization with mapped QTLs. A genetic linkage map was constructed using EST-SSR markers in
a population of 130 BC1F1 plants derived from the cross between Al-sensitive and Al-tolerant genotypes. Three putative QTLs on linkage groups LG I,
LG II and LG III, explaining 38, 16 and 27% of the phenotypic variation, respectively, were identified. Six candidate gene
markers designed from Medicago truncatula ESTs that showed homology to known Al-tolerance genes identified in other plant species were placed on the QTL map. A marker
designed from a candidate gene involved in malic acid release mapped near a marginally significant QTL (LOD 2.83) on LG I.
The SSR markers flanking these QTLs will be useful for transferring them to cultivated alfalfa via marker-assisted selection
and for pyramiding Al tolerance QTLs. 相似文献
18.
P. K. Tanhuanpää J. P. Vilkki H. J. Vilkki 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(3):477-480
F2 progeny (105 individuals) from the cross Jo4002 x Sv3402 were used to identify DNA markers associated with palmitic-acid content in spring turnip rape (Brassica rapa ssp. oleifera). QTL mapping and ANOVA analysis of 140 markers exposed one linkage group with a locus controlling palmitic-acid content (LOD score 27), and one RAPD (random amplified polymorphic DNA) marker, OPB-11a, closely linked (1.4 cM) to this locus. Palmitic-acid content in the 62 F2 plants with the visible allele of marker OPB-11a was 8.45 ±3.15%, while that in the 24 plants without it was 4.59 ±0.97%. As oleic-acid concentration is affected by a locus on the same linkage group as the palmitic-acid locus, this locus probably controls the chain elongation from palmitic acid to oleic acid (through stearic acid). Marker OPB-11a may be used in future breeding programs of spring turnip rape to simplify and hasten the selection for palmitic-acid content. 相似文献
19.
M. C. Moretzsohn C. D. M. Nunes M. E. Ferreira D. Grattapaglia 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(1):63-70
Shell thickness is an important trait in oil palm breeding programs and is the basis for the classification of the varieties
of oil palm into the types dura, tenera and pisifera. This trait seems to be controlled by a single locus, with two alleles
(sh
+ and sh
−) showing codominant expression. Two single-tree linkage maps were constructed for a maternal tenera (sh
+
sh
−) palm and for a paternal pisifera (sh
−
sh
−) palm using the pseudo-testcross mapping strategy in combination with RAPD markers through the analysis of an F1 tenera×pisifera progeny. A total of 308 arbitrary primers were screened in a sample of eight F1 plants and 121 markers were detected in a testcross configuration. An average of 1.66 polymorphic marker per selected primer
were identified in this cross. At LOD 5.0 (with some few exceptions) and θ=0.25 the maternal tenera map included a total of
48 markers distributed in 12 linkage groups or pairs of markers (449.3 cM) while the paternal pisifera map included 42 markers
distributed in 15 linkage groups or pairs of markers (399.7 cM). We used RAPD and bulked segregant analysis (BSA) to identify
markers more tightly linked to the sh
+ locus. A total of 174 new primers not previously used in the linkage analysis were screened using bulks of DNA extracted
from plants selected for the contrasting shell-thickness phenotypes. Two RAPD markers (R11–1282 and T19–1046) were identified
to be linked on both sides of the sh
+ locus on linkage group 4. The estimated map distances from sh
+ to R11–1282 and to T19–1046 were 17.5 cM and 23.9 cM, respectively. The results demonstrate the usefulness of RAPD markers
and the pseudo-testcross mapping strategy for developing genetic linkage information, and constitute an important step towards
early marker-assisted selection for shell thickness in oil palm.
Received: 21 February 1999 / Accepted: 29 April 1999 相似文献
20.
Marczewski W Flis B Syller J Strzelczyk-Zyta D Hennig J Gebhardt C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(8):1604-1609
A novel locus for potato resistance to potato leafroll virus (PLRV) was characterized by inheritance studies and molecular mapping. The diploid parental clone DW 91-1187 was resistant to PLRV accumulation in both inoculated plants and their tuber progeny. The resistance to PLRV accumulation present in DW 91-1187 was not transmitted to any F1 offspring when crossed with a PLRV susceptible clone. Instead, one half of the F1 individuals exhibited undetectable amounts of PLRV as determined by ELISA during the primary infection assay, but accumulated PLRV in their tuber progeny plants. The other half was clearly infected both in the inoculated and tuber-born plants. The inheritance of resistance to PLRV accumulation may be explained by a model of two complementary alleles of a single gene (PLRV.4) or by two complementary genes that are closely linked in repulsion phase. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers linked to the PLRV.4 locus were selected. The two complementary factors were closely linked in coupling phase to the alternative alleles UBC864600 and UBC864800 of DNA marker UBC864. These markers may be used for marker-assisted selection of genotypes having both factors for resistance to PLRV accumulation. The PLRV.4 locus was mapped to a central position on linkage group XI of the potato molecular map, where no resistance locus has been mapped previously. 相似文献