Identification of Random Amplified Polymorphic DNA Markers Linked to Sex Determination in Calamus simplicifolius C. F. Wei.

Surian Toona sinensis Roem is one of the most widely planted species in Indonesia. This study aimed to estimate the genetic diversity between a number of surian populations in a progeny test using RAPD markers, with the goal of proposing management strategies for a surian breeding program. Ninety-six individual trees from 8 populations of surian were chosen as samples for analysis. Eleven polymorphic primers (OP-B3, OP-B4, OP-B10, OP-H3, OP-Y6, OP-Y7, OP-Y8, OP-Y10, OP-Y11, OP-Y14, and OP-06) producing reproducible bands were analyzed for the 96 trees, with six trees per family sampled. Data were analyzed using GenAlEx 6.3, NTSYS 2.02. The observed percentage of polymorphic loci ranged from 18.2% to 50%. The mean level of genetic diversity among the surian populations was considered to be moderate (He 0.304). Cluster analysis grouped the genotypes into two main clusters, at similarity levels of 0.68 and 0.46. The first two axes of the PCoA explained 46.16% and 25.54% of the total variation, respectively. The grouping of samples into clusters and subclusters did not correspond with family and their distances, but the grouping was in line with the genetic distances of the samples.

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The Genetic Variability of Sicilian Lemon Germplasm Revealed by Molecular Marker Fingerprints

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.133.2.242 ◽

2008 ◽

Vol 133 (2) ◽

pp. 242-248 ◽

Cited By ~ 3

Author(s):

Mirko Siragusa ◽

Fabio De Pasquale ◽

Loredana Abbate ◽

Letizia Martorana ◽

Nicasio Tusa

Keyword(s):

Dna Markers ◽

Random Amplified Polymorphic Dna ◽

Citrus Limon ◽

Genetic Isolation ◽

Breeding Programs ◽

Bud Mutation ◽

Italian Regions ◽

Wide Range ◽

High Level ◽

Polymorphic Nature

There is a high level of diversity among lemons [Citrus limon (L.) Burm. f. (2n = 2x = 18)] in Sicily, where each growing area has a wide range of landraces mostly derived from bud mutation. Because this variability represents an important resource for future breeding programs and genetic improvement, the relationships among the principal 36 accessions of Sicilian lemon, belonging to three different cultivars (Femminello, Monachello, and Lunario), were examined by intersimple sequence repeat and random amplified polymorphic DNA markers. Three ‘Femminello’ accessions from nearby Italian regions were also examined to study the genetic flow from the continent. The disputed case of the accession ‘Eureka Messina lemon’ was also examined, using ‘Frost Eureka’ as a control. Our results confirmed the extreme polymorphic nature of the three principal Sicilian cultivars and the presence of a wide range of different genotypes. Twenty-two Sicilian genotypes were recognized as unique accessions, reflecting the richness of the lemon germplasm present in Sicily. Each growing area showed the presence of several genetically different landraces, probably preserved by genetic isolation, whereas the continental accessions appeared extremely similar to the island genotypes, showing an exchange of germplasm from the island to the continent.

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Segregation of random amplified polymorphic DNA markers and strategies for molecular mapping in tetraploid alfalfa

Genome ◽

10.1139/g93-112 ◽

1993 ◽

Vol 36 (5) ◽

pp. 844-851 ◽

Cited By ~ 23

Author(s):

K. F. Yu ◽

K. P. Pauls

Keyword(s):

Chromosome Segregation ◽

Dna Markers ◽

Rapd Markers ◽

Molecular Mapping ◽

Random Amplified Polymorphic Dna ◽

Rapd Marker ◽

Female Parent ◽

Linkage Groups ◽

Double Reduction ◽

Chromatid Segregation

An F1 population was used to analyze the inheritance of random amplified polymorphic DNA (RAPD) markers in tetraploid alfalfa. Of the 32 RAPD markers that were used for a segregation analysis in this study, 27 gave ratios that are consistent with random chromosome and random chromatid segregation at meiosis. However, among all of the RAPD markers (121) that were screened in this study, only one example of a double reduction, that is typical of chromatid segregation, was observed. These results indicate that random chromosome segregation is likely the predominant but not the exclusive mode of inheritance for tetraploid alfalfa. χ2 analyses of cosegregation for RAPD marker pairs derived from the female parent revealed nine linkages that fell into four linkage groups. The recombination fractions among linked marker pairs ranged from 1 to 37%. These are the first molecular linkage groups reported in tetraploid alfalfa. In addition, various strategies for molecular mapping in the tetraploid alfalfa genome are proposed that should be of interest to plant breeders who are planning to use molecular markers for alfalfa or other tetraploid species.Key words: RAPD markers, tetraploid alfalfa, segregation, linkage groups.

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Genetic mapping and non-Mendelian segregation of mating type loci in the oomycete, Phytophthora infestans.

Genetics ◽

10.1093/genetics/141.2.503 ◽

1995 ◽

Vol 141 (2) ◽

pp. 503-512 ◽

Cited By ~ 2

Author(s):

H S Judelson ◽

L J Spielman ◽

R C Shattock

Keyword(s):

Phytophthora Infestans ◽

Mating Type ◽

Dna Markers ◽

Bulked Segregant Analysis ◽

Random Amplified Polymorphic Dna ◽

Mating Types ◽

Mendelian Segregation ◽

Range Restriction ◽

Type Locus ◽

Mating Type Locus

Abstract DNA markers linked to the determinants of mating type in the oomycete, Phytophthora infestans, were identified and used to address the genetic basis of heterothallism in the normally diploid fungus. Thirteen loci linked to the A1 and A2 mating types were initially identified by bulked segregant analysis using random amplified polymorphic DNA markers (RAPDs) and subsequently scored in three crosses polymorphisms (SSCP), cleaved amplified polymorphisms (CAPS), or allele-specific polymerase chain reaction markers (AS-PCR). All DNA markers mapped to a single region, consistent with a single locus determining both mating types. Long-range restriction mapping also demonstrated the linkage of the markers to one region and delimited the mating type locus to a 100-kb region. The interval containing the mating type locus displayed non-Mendelian segregation as only two of the four expected genotypes were detected in progeny. This is consistent with a system of balance lethal loci near the mating type locus. A model for mating type determination is presented in which the balanced lethals exclude form progeny those with potentially conflicting combinations of mating type alleles, such as those simultaneously expressing A1 and A2 functions.

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Linkage Analysis of Sex Determination in Bracon sp. Near hebetor (Hymenoptera: Braconidae)

Genetics ◽

10.1093/genetics/154.1.205 ◽

2000 ◽

Vol 154 (1) ◽

pp. 205-212

Author(s):

Alisha K Holloway ◽

Michael R Strand ◽

William C Black ◽

Michael F Antolin

Keyword(s):

Linkage Group ◽

Sex Determination ◽

Rapd Markers ◽

Random Amplified Polymorphic Dna ◽

Parasitic Wasp ◽

Specific Pattern ◽

Diploid Males ◽

Phenotypic Marker ◽

Group I ◽

Sex Locus

Abstract To test whether sex determination in the parasitic wasp Bracon sp. near hebetor (Hymenoptera: Braconidae) is based upon a single locus or multiple loci, a linkage map was constructed using random amplified polymorphic DNA (RAPD) markers. The map includes 71 RAPD markers and one phenotypic marker, blonde. Sex was scored in a manner consistent with segregation of a single “sex locus” under complementary sex determination (CSD), which is common in haplodiploid Hymenoptera. Under haplodiploidy, males arise from unfertilized haploid eggs and females develop from fertilized diploid eggs. With CSD, females are heterozygous at the sex locus; diploids that are homozygous at the sex locus become diploid males, which are usually inviable or sterile. Ten linkage groups were formed at a minimum LOD of 3.0, with one small linkage group that included the sex locus. To locate other putative quantitative trait loci (QTL) for sex determination, sex was also treated as a binary threshold character. Several QTL were found after conducting permutation tests on the data, including one on linkage group I that corresponds to the major sex locus. One other QTL of smaller effect had a segregation pattern opposite to that expected under CSD, while another putative QTL showed a female-specific pattern consistent with either a sex-differentiating gene or a sex-specific deleterious mutation. Comparisons are made between this study and the indepth studies on sex determination and sex differentiation in the closely related B. hebetor.

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