A genetic linkage map in autotetraploid lucerne adapted to northern Australia, and use of the map to identify DNA markers linked to resistance to Phytophthora medicaginis

2005 ◽  
Vol 56 (4) ◽  
pp. 333 ◽  
Author(s):  
J. M. Musial ◽  
K. S. Aitken ◽  
J. M. Mackie ◽  
J. A. G. Irwin
Keyword(s):  
Linkage Map ◽  
Phenotypic Variation ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Average Distance ◽  
Linkage Groups ◽  
Resistance Qtls ◽  
Backcross Population ◽  
Resistant Parent ◽  
Repulsion Phase

Phytophthora root rot, caused by Phytophthora medicaginis, is a major limitation to lucerne (Medicago sativa L.) production in Australia and North America. Quantitative trait loci (QTLs) involved in resistance to P. medicaginis were identified in a lucerne backcross population of 120 individuals. A genetic linkage map was constructed for tetraploid lucerne using 50 RAPD (randomly amplified polymorphic DNA), 104 AFLP (amplified fragment length polymorphism) markers, and one SSR (simple sequence repeat or microsatellite) marker, which originated from the resistant parent (W116); 13 markers remain unlinked. The linkage map contains 18 linkage groups covering 2136.5 cM, with an average distance of 15.0 cM between markers. Four of the linkage groups contained only either 2 or 3 markers. Using duplex markers and repulsion phase linkages the map condensed to 7 homology groups and 2 unassigned linkage groups. Three regions located on linkage groups 2, 14, and 18, were identified as associated with root reaction and the QTLs explained 6–15% of the phenotypic variation. The research also indicates that different resistance QTLs are involved in conferring resistance in different organs. Two QTLs were identified as associated with disease resistance expressed after inoculation of detached leaves. The marker, W11-2 on group 18, identified as associated with root reaction, contributed 7% of the phenotypic variation in leaf response in our population. This marker appears to be linked to a QTL encoding a resistance factor contributing to both root and leaf reaction. One other QTL, not identified as associated with root reaction, was positioned on group 1 and contributed to 6% of the variation. This genetic linkage map provides an entry point for future molecular-based improvement of lucerne in Australia, and markers linked to the QTLs we have reported should be useful for marker-assisted selection for partial resistance to P. medicaginis in lucerne.

A genetic linkage map for Stevia rebaudiana

Genome ◽  
1999 ◽  
Vol 42 (4) ◽  
pp. 657-661 ◽  
Author(s):  
Y Yao ◽  
M Ban ◽  
J Brandle
Keyword(s):  
Linkage Map ◽  
Genetic Linkage ◽  
Rapd Markers ◽  
Genetic Linkage Map ◽  
Average Distance ◽  
Stevia Rebaudiana ◽  
Linkage Groups ◽  
Genome Map ◽  
High Level ◽  
Map Distance

To lay a foundation for molecular breeding efforts, the first genetic linkage map for Stevia rebaudiana has been constructed using segregation data from a pseudo test-cross F1 population. A total of 183 randomly amplified polymorphic DNA (RAPD) markers were analysed and assembled into 21 linkage groups covering a total distance of 1389 cM, with an average distance between markers of of 7.6 cM. The 11 largest linkage groups consisted of 4-19 loci, ranged in length from 56 to 174 cM, and accounted for 75% of the total map distance. Fifteen RAPD loci were found to be unlinked. From the 521 primers showing amplification products, 185 (35.5%) produced a total of 293 polymorphic fragments, indicating a high level of genetic diversity in stevia. Most of the RAPD markers in stevia segregated in normal Mendelian fashion.Key words: stevia, open-pollinated, genome map, RAPD.

Linkage of random amplified polymorphic DNA, isozyme and morphological markers in grasspea (Lathyrus sativus)

1999 ◽  
Vol 133 (4) ◽  
pp. 389-395 ◽  
Author(s):  
M. A. CHOWDHURY ◽  
A. E. SLINKARD
Keyword(s):  
Linkage Map ◽  
Genetic Linkage ◽  
Rapd Markers ◽  
Genetic Linkage Map ◽  
Average Distance ◽  
Random Amplified Polymorphic Dna ◽  
Lathyrus Sativus ◽  
Morphological Markers ◽  
Linkage Studies ◽  
Linkage Groups

We constructed a genetic linkage map of grasspea (Lathyrus sativus L.; 2n = 14) from 100 F2 individuals derived from a cross between PI 426891.1.3 and PI 283564c.3.2. A total of 71 RAPD, three isozyme and one morphological markers segregated in the F2 progeny. A small fraction of markers (12%) deviated significantly from the expected Mendelian ratio (1[ratio ]2[ratio ]1 or 3[ratio ]1). Out of 75 markers, 69 (one morphological, three isozyme and 65 RAPD markers) were assigned to 14 linkage groups comprising 898 cM. The average distance between two adjacent markers was 17·2 cM. The present linkage map will serve as a reference point for further linkage studies in grasspea.

scholarly journals A Genetic Linkage Map of BC2 Population Reveals QTL Associated with Plant Architecture Traits in Lagerstroemia

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 322
Author(s):  
Yang Zhou ◽  
Yuanjun Ye ◽  
Lu Feng ◽  
Ye Zhang ◽  
Qifang Lin ◽  
...  
Keyword(s):  
Linkage Map ◽  
Plant Height ◽  
Phenotypic Variation ◽  
Genetic Linkage ◽  
Plant Architecture ◽  
Genetic Linkage Map ◽  
Lateral Branch ◽  
Linkage Groups ◽  
Crown Width ◽  
Primary Lateral

Plant architecture improvement is of great significance in influencing crop yield, harvesting efficiency and ornamental value, by changing the spatial structure of the canopy. However, the mechanism on plant architecture in woody plants is still unclear. In order to study the genetic control of plant architecture traits and promote marker-assisted selection (MAS), a genetic linkage map was constructed, and QTL mapping was performed. In this study, using 188 BC2 progenies as materials, a genetic map of Lagerstroemia was constructed using amplification fragment length polymorphisms (AFLP) and simple sequence repeats (SSR) markers, and the QTLs of four key plant architecture traits (plant height, crown width, primary lateral branch height and internode length) were analyzed. The genetic map contains 22 linkage groups, including 198 AFLP markers and 36 SSR markers. The total length of the genome covered by the map is 1272 cM, and the average distance between markers is 6.8 cM. Three QTLs related to plant height were located in LG1, LG4 and LG17 linkage groups, and the phenotypic variation rates were 32.36, 16.18 and 12.73%, respectively. A QTL related to crown width was located in LG1 linkage group, and the phenotypic variation rate was 18.07%. Two QTLs related to primary lateral branch height were located in the LG1 and LG7 linkage groups, and the phenotypic variation rates were 20.59 and 15.34%, respectively. Two QTLs related to internode length were located in the LG1 and LG20 linkage groups, and the phenotypic variation rates were 14.86 and 9.87%. The results provide a scientific basis for finely mapping genes of plant architecture traits and marker-assisted breeding in Lagerstroemia.

scholarly journals Construction of a genetic linkage map of cigar tobacco (Nicotiana tabacum L.) based on SSR markers and comparative studies

2018 ◽  
Vol 54 (No. 3) ◽  
pp. 115-122 ◽  
Author(s):  
Tong Zhijun ◽  
Xiao Bingguang ◽  
Chen Xuejun ◽  
Fang Dunhuang ◽  
Zhang Yihan ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Nicotiana Tabacum ◽  
Linkage Map ◽  
Ssr Markers ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Average Distance ◽  
Backcross Population ◽  
Breeding Programs ◽  
Nicotiana Tabacum L

Genetic linkage maps representing the tobacco genome have been an important tool for breeding programs because of the elucidation of polygenic traits. We constructed a genetic linkage map of cigar tobacco (Nicotiana tabacum L.) based on an inter-type backcross population of 213 individuals and performed a comparative analysis with other published maps of dark tobacco and flue-cured tobacco. The map consisted of 562 SSR loci distributed on 24 tentative linkage groups and spanned a total length of 1341.18 cM with an average distance of 2.39 cM between adjacent markers. The comparative analysis revealed a Spearman correlation index of 0.93 for marker order conservation with the previously published maps constructed for different tobacco types. Approximately 91% of the SSR markers common to other inter-type maps were located in the same positions as in previous maps. The three maps exhibit good synteny in terms of the shared markers, which suggests that there might be no translocation variations between the genomes of the cigar, dark and flue-cured tobaccos. These results indicate the feasibility of generating a unique genetic map of preferred traits in cigar tobacco and that such mapping may be helpful for breeding programs because plants derived from different inter-type populations can be rapidly scanned using the markers associated with useful cigar traits

Constructing a genetic linkage map and mapping quantitative trait loci for skeletal traits in Japanese flounder

Biologia ◽  
2013 ◽  
Vol 68 (6) ◽  
Author(s):  
Yi Liu ◽  
Yongxin Liu ◽  
Yingjie Liu ◽  
Xiaoyan Zhang ◽  
Fei Si ◽  
...  
Keyword(s):  
Linkage Map ◽  
Quantitative Trait ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Expressed Sequence Tag ◽  
Average Distance ◽  
Doubled Haploids ◽  
Japanese Flounder ◽  
Type Ii ◽  
Linkage Groups

AbstractA genetic linkage map of Japanese flounder was constructed using 165 doubled haploids (DHs) derived from a single female. A total of 574 genomic microsatellites (type II SSRs) and expressed sequence tag (EST)-derived markers (EST-SSRs) were mapped to 24 linkage groups. The length of linkage map was estimated as 1270.9 centiMorgans (cM), with an average distance between markers of 2.2 cM. The EST-SSRs were used together with type II SSR markers to construct the Japanese flounder genetic linkage map which will facilitate identify quantitative trait locus (QTL) controlling important economic traits in Japanese flounder. Thus, twelve skeletal traits at 2 years of age were measured for all DHs. Forty-one QTLs were detected on 14 linkage groups and totally account for a small proportion of phenotypic variation (4.5 to 17.3%). Most of QTLs detected distribute on linkage groups 5 (9 QTLs), 8 (9 QTLs), 9 (5 QTLs) and 20 (4 QTLs), in which, some QTLs perform the pleiotropy.

The First Comprehensive Genetic Linkage Map of a Marsupial: The Tammar Wallaby (Macropus eugenii)

Genetics ◽  
2002 ◽  
Vol 162 (1) ◽  
pp. 321-330 ◽  
Author(s):  
Kyall R Zenger ◽  
Louise M McKenzie ◽  
Desmond W Cooper
Keyword(s):  
Linkage Map ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Average Distance ◽  
Tammar Wallaby ◽  
Chromosome 1 ◽  
Linkage Groups ◽  
Recombination Rates ◽  
Macropus Eugenii ◽  
Significant Linkage

AbstractThe production of a marsupial genetic linkage map is perhaps one of the most important objectives in marsupial research. This study used a total of 353 informative meioses and 64 genetic markers to construct a framework genetic linkage map for the tammar wallaby (Macropus eugenii). Nearly all markers (93.8%) formed a significant linkage (LOD > 3.0) with at least one other marker, indicating that the majority of the genome had been mapped. In fact, when compared with chiasmata data, >70% (828 cM) of the genome has been covered. Nine linkage groups were identified, with all but one (LG7; X-linked) allocated to the autosomes. These groups ranged in size from 15.7 to 176.5 cM and have an average distance of 16.2 cM between adjacent markers. Of the autosomal linkage groups (LGs), LG2 and LG3 were assigned to chromosome 1 and LG4 localized to chromosome 3 on the basis of physical localization of genes. Significant sex-specific distortions toward reduced female recombination rates were revealed in 22% of comparisons. When comparing the X chromosome data to closely related species it is apparent that they are conserved in both synteny and gene order.

scholarly journals Genetic Linkage Map of the Edible BasidiomycetePleurotus ostreatus

2000 ◽  
Vol 66 (12) ◽  
pp. 5290-5300 ◽  
Author(s):  
Luis M. Larraya ◽  
G�mer P�rez ◽  
Enrique Ritter ◽  
Antonio G. Pisabarro ◽  
Lucı́a Ramı́rez
Keyword(s):  
Linkage Map ◽  
Genetic Linkage ◽  
Gene Sequence ◽  
Genetic Linkage Map ◽  
Fragment Length Polymorphism ◽  
Individual Cell ◽  
Random Amplified Polymorphic Dna ◽  
Rrna Gene ◽  
Linkage Groups ◽  
Rrna Gene Sequence

ABSTRACT We have constructed a genetic linkage map of the edible basidiomycete Pleurotus ostreatus (var. Florida). The map is based on the segregation of 178 random amplified polymorphic DNA and 23 restriction fragment length polymorphism markers; four hydrophobin, two laccase, and two manganese peroxidase genes; both mating type loci; one isozyme locus (est1); the rRNA gene sequence; and a repetitive DNA sequence in a population of 80 sibling monokaryons. The map identifies 11 linkage groups corresponding to the chromosomes ofP. ostreatus, and it has a total length of 1,000.7 centimorgans (cM) with an average of 35.1 kbp/cM. The map shows a high correlation (0.76) between physical and genetic chromosome sizes. The number of crossovers observed per chromosome per individual cell is 0.89. This map covers nearly the whole genome of P. ostreatus.

Mapping of quantitative trait loci underlying resistance to cassava anthracnose disease

2015 ◽  
Vol 154 (7) ◽  
pp. 1209-1217 ◽  
Author(s):  
A. BOONCHANAWIWAT ◽  
S. SRAPHET ◽  
S. WHANKAEW ◽  
O. BOONSENG ◽  
D. R. SMITH ◽  
...  
Keyword(s):  
Quantitative Trait Loci ◽  
Linkage Map ◽  
Dna Markers ◽  
Quantitative Trait ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Gene Annotation ◽  
Linkage Groups ◽  
Anthracnose Disease ◽  
Trait Loci

SUMMARYCassava (Manihot esculenta Crantz) is an economically important root crop in Thailand, which is ranked the world's top cassava exporting country. Production of cassava can be hampered by several pathogens and pests. Cassava anthracnose disease (CAD) is an important disease caused by the fungus Colletotrichum gloeosporioides f. sp. manihotis. The pathogen causes severe stem damage resulting in yield reductions and lack of stem cuttings available for planting. Molecular studies of cassava response to CAD will provide useful information for cassava breeders to develop new varieties with resistance to the disease. The current study aimed to identify quantitative trait loci (QTL) and DNA markers associated with resistance to CAD. A total of 200 lines of two F1 mapping populations were generated by reciprocal crosses between the varieties Huabong60 and Hanatee. The F1 samples were genotyped based on simple sequence repeat (SSR) and expressed sequence tag-SSR markers and a genetic linkage map was constructed using the JoinMap®/version3·0 program. The results showed that the map consisted of 512 marker loci distributed on 24 linkage groups with a map length of 1771·9 centimorgan (cM) and a mean interval between markers of 5·7 cM. The genetic linkage map was integrated with phenotypic data for the response to CAD infection generated by a detached leaf assay test. A total of three QTL underlying the trait were identified on three linkage groups using the MapQTL®/version4·0 program. Those DNA markers linked to the QTL that showed high statistically significant values with the CAD resistance trait were identified for gene annotation analysis and 23 candidate resistance genes to CAD infection were identified.

scholarly journals Development of a genetic linkage map for Sharon goatgrass (Aegilops sharonensis) and mapping of a leaf rust resistance gene

Genome ◽  
2013 ◽  
Vol 56 (7) ◽  
pp. 367-376 ◽  
Author(s):  
P.D. Olivera ◽  
A. Kilian ◽  
P. Wenzl ◽  
B.J. Steffenson
Keyword(s):  
Linkage Map ◽  
Leaf Rust ◽  
Resistance Genes ◽  
Genetic Linkage ◽  
Genetic Linkage Map ◽  
Chromosomal Location ◽  
Dominant Gene ◽  
Leaf Rust Resistance Gene ◽  
Linkage Groups ◽  
Aegilops Sharonensis

Aegilops sharonensis (Sharon goatgrass), a diploid wheat relative, is known to be a rich source of disease resistance genes for wheat improvement. To facilitate the transfer of these genes into wheat, information on their chromosomal location is important. A genetic linkage map of Ae. sharonensis was constructed based on 179 F2 plants derived from a cross between accessions resistant (1644) and susceptible (1193) to wheat leaf rust. The linkage map was based on 389 markers (377 Diversity Arrays Technology (DArT) and 12 simple sequence repeat (SSR) loci) and was comprised of 10 linkage groups, ranging from 2.3 to 124.6 cM. The total genetic length of the map was 818.0 cM, with an average interval distance between markers of 3.63 cM. Based on the chromosomal location of 115 markers previously mapped in wheat, the four linkage groups of A, B, C, and E were assigned to Ae. sharonensis (Ssh) and homoeologous wheat chromosomes 6, 1, 3, and 2. The single dominant gene (designated LrAeSh1644) conferring resistance to leaf rust race THBJ in accession 1644 was positioned on linkage group A (chromosome 6Ssh) and was flanked by DArT markers wpt-9881 (at 1.9 cM distal from the gene) and wpt-6925 (4.5 cM proximal). This study clearly demonstrates the utility of DArT for genotyping uncharacterized species and tagging resistance genes where pertinent genomic information is lacking.

Sign in / Sign up

Export Citation Format

Share Document