Non-aggressive Strains of the Blackleg Fungus, Leptosphaeria maculans, Are Present in Australia and Can Be Distinguished From Aggressive Strains by Molecular Analysis

1994 ◽  
Vol 42 (1) ◽  
pp. 1 ◽  
Author(s):  
KM Plummer ◽  
K Dunse ◽  
BJ Howlett
Keyword(s):  
Brassica Napus ◽  
North America ◽  
Molecular Analysis ◽  
Ribosomal Rna ◽  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Leptosphaeria Maculans ◽  
Morphological Characters ◽  
Molecular Techniques ◽  
Blackleg Fungus

Isolates of the pathogenic ascomycete Leptosphaeria maculans have been cultured from blackleg-affected oilseed rape (Brassica napus) stubble from Horsham, Victoria. These isolates are indistinguishable on the basis of morphological characters, but can be classified as either aggressive or non-aggressive by their ability to infect B. napus cultivars Midas and Westar. These aggressive and non-aggressive isolates of L. maculans can be distinguished by molecular techniques including electrophoretic karyotyping, Southern analysis of the ribosomal RNA gene repeat, Random Amplified Polymorphic DNA (RAPD) marker analysis, and pigment production. The presence of aggressive and non-aggressive strains of L. maculans in North America and Europe has been previously described. This is the first report of non-aggressive L. maculans strains isolated from B. napus in Australia.

Variation in the responses of rapeseed (Brassica napus and B. campestris) cultivars to blackleg (Leptosphaeria maculans) infection

1977 ◽  
Vol 17 (86) ◽  
pp. 445 ◽  
Author(s):  
N Thurling ◽  
LA Venn
Keyword(s):  
Brassica Napus ◽  
Significant Variation ◽  
Brassica Campestris ◽  
Leptosphaeria Maculans ◽  
The Other ◽  
Controlled Environment ◽  
Disease Development ◽  
Fungal Populations ◽  
Different Populations ◽  
Blackleg Fungus

The responses of 53 cultivars of the rapeseed species Brassica napus and Brassica campestris to infection by three different populations of the blackleg fungus, Leptosphaeria maculans, were examined in a controlled environment. Significant variation in disease development was observed between cultivars as well as between fungal populations which had been derived from diseased stubble collected at widely separated sites in Western Australia. A large proportion of the cultivars tested were either susceptible or only slightly resistant to infection by each of the three fungal populations whereas only one cultivar, Zollerngold, was highly resistant to all fungal populations. Several other cultivars, however, were resistant to one population and susceptible or slightly resistant to the other two. In these cases, marked interactions between host and parasite were evident, some cultivars being substantially more resistant than others to infection by spores from a particular population.

scholarly journals Molecular techniques in the assessment of genetic relationships between populations of Consolida (Ranunculaceae)

Caryologia ◽  
2021 ◽  
Vol 74 (2) ◽  
pp. 149-161
Author(s):  
Jing Ma ◽  
Wenyan Fan ◽  
Shujun Jiang ◽  
Xiling Yang ◽  
Wenshuai Li ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Relationships ◽  
Random Amplified Polymorphic Dna ◽  
Principal Component ◽  
Morphological Characters ◽  
Mantel Test ◽  
Molecular Techniques ◽  
Group Method ◽  
Plant Resources ◽  
High Genetic Diversity

Genetic diversity studies are essential to understand the conservation and management of plant resources in any environment. The genus Consolida (DC.) Gray (Ranuculaceae) belongs to tribe Delphinieae. It comprises approximately 52 species, including the members of the genus Aconitella Spach. No detailed Random Amplified Polymorphic DNA (RAPD) studies were conducted to study Consolida genetic diversity. Therefore, we collected and analyzed 19 species from 12 provinces of regions. Overall, one hundred and twenty-seven plant specimens were collected. We showed significant differences in quantitative morphological characters in plant species. Unweighted pair group method with arithmetic mean and principal component analysis (PCA) divided Consolida species into two groups. All primers produced polymorphic amplicons though the extent of polymorphism varied with each primer. The primer OPA-06 was found to be most powerful and efficient as it generated a total of 24 bands of which 24 were polymorphic. The Mantel test showed correlation (r = 0.34, p=0.0002) between genetic and geographical distances. We reported high genetic diversity, which clearly shows the Consolida species can adapt to changing environments since high genetic diversity is linked to species adaptability. Present results highlighted the utility of RAPD markers and morphometry methods to investigate genetic diversity in Consolida species. Our aims were 1) to assess genetic diversity among Consolida species 2) is there a correlation between species genetic and geographical distance? 3) Genetic structure of populations and taxa.

scholarly journals Evaluation of genetic diversity in geranium (Geraniaceae) using RAPD marker

Genetika ◽  
2021 ◽  
Vol 53 (1) ◽  
pp. 363-378
Author(s):  
Juan Yin ◽  
Majid Khayatnezhad ◽  
Abdul Shakoor
Keyword(s):  
Genetic Diversity ◽  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Morphological Characters ◽  
Mantel Test ◽  
Group Method ◽  
Plant Resources ◽  
High Genetic Diversity ◽  
Pair Group ◽  
Genetic Structure Of Populations

Genetic diversity studies are essential to understand the conservation and management of plant resources in any environment. No detailed Random Amplified Polymorphic DNA (RAPD) studies were conducted to study Geranium genetic diversity. Therefore, we collected and analyzed thirteen species from nine provinces. Overall, one hundred and twenty-five plant specimens were collected. Our aims were 1) to assess genetic diversity among Geranium species 2) is there a correlation between species genetic and geographical distance? 3) Genetic structure of populations and taxa. We showed significant differences in quantitative morphological characters in plant species. Unweighted pair group method with arithmetic mean and multidimensional scaling divided Geranium species into two groups. G. sylvaticum depicted unbiased expected heterozygosity (UHe) in the range of 0.11. Shannon information was high (0.38) in G. columbinum. G. sylvaticum showed the lowest value, 0.14. The observed number of alleles (Na) ranged from 0.25 to 0.55 in G. persicum and G. tuberosum. The effective number of alleles (Ne) was in the range of 1.020-1.430 for G. tuberosum and G. collinum. Gene flow (Nm) was relatively low (0.33) in Geranium. The Mantel test showed correlation (r = 0.27, p=0.0002) between genetic and geographical distances. We reported high genetic diversity, which clearly shows the Geranium species can adapt to changing environments since high genetic diversity is linked to species adaptability. Present results highlighted the utility of RAPD markers and morphometry methods to investigate genetic diversity in Geranium species.

scholarly journals A comparative analysis of genetic diversity in Portuguese grape germplasm from ampelographic collections fit for quality wine production

2016 ◽  
Vol 14 (4) ◽  
pp. e0712 ◽  
Author(s):  
Isaura Castro ◽  
Olinda Pinto-Carnide ◽  
Jesús M. Ortiz ◽  
Vanessa Ferreira ◽  
Juan P. Martín
Keyword(s):  
Genetic Diversity ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characters ◽  
Inter Simple Sequence Repeat ◽  
Issr Markers ◽  
Molecular Techniques ◽  
Wine Production ◽  
Rapd And Issr ◽  
Simple Sequence

Grapevine cultivars diversity is vast and full of synonyms and homonyms. Up to few decades ago characterization of grapevine was based on morphological characters. In the last decades, molecular markers were developed and have been used as tools to study genetic diversity in a range of different plant species. Fifty-six Portuguese accessions representative of ‘Vinhos Verdes’ and ‘Douro’ Controlled Designations of Origin (DOC) were analysed through DNA fingerprints generated by Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR). The study aimed to compare the effectiveness of RAPD and ISSR molecular techniques in the detection of synonyms, homonyms and misnames. RAPD and ISSR analysis enabled the detection of 36 different band patterns, reducing in about 36% the initial material. Several accessions grown under different names, between and within collections, were confirmed as the same genotype, namely Gouveio/Verdelho, Sousão Douro/Vinhão and Arinto Oeste/Pedernã. Similarly, some homonyms/misnames were also identified, namely within Azal Tinto and Rabigato accessions. RAPD and ISSR markers revealed to be adequate molecular techniques for grapevine varieties fingerprinting with advantages over other molecular procedures, contributing for a good management of grapevine collections.

scholarly journals A maximalist approach to the systematics of a biological control agent: Gryon aetherium Talamas, sp. nov. (Hymenoptera, Scelionidae)

2021 ◽  
Vol 87 ◽  
pp. 323-480 ◽  
Author(s):  
Elijah J. Talamas ◽  
Jonathan S. Bremer ◽  
Matthew R. Moore ◽  
Marie-Claude Bon ◽  
Zachary Lahey ◽  
...  
Keyword(s):  
Biological Control ◽  
North America ◽  
Molecular Analysis ◽  
Biological Control Agent ◽  
Field Studies ◽  
Morphological Characters ◽  
Control Agent

A morphological and molecular analysis of Gryon Haliday (Platygastroidea, Scelionidae) was conducted to provide a taxonomic and phylogenetic context for a species under evaluation as a biological control agent of Bagrada hilaris (Burmeister) (Hemiptera, Pentatomidae). Our analysis revealed that Gryon is polyphyletic and that the biological control agent is not G. gonikopalense, a name that was tentatively applied to this species in 2019. We here describe this species as new, Gryon aetherium Talamas sp. nov., and resurrect the generic name Hadronotus Förster. Morphological characters that delimit our concepts of Gryon and Hadronotus are presented. Based on morphological characters and multilocus phylogenies, we determined that five presently valid scelionid genera belong within Gryon. In total, 15 species are transferred into Gryon from these genera, 215 species are transferred from Gryon to Hadronotus, and 6 species are transferred from Gryon to Dyscritobaeus Perkins. Specimens collected during field studies in California and reevaluation of specimens determined as G. myrmecophilum in Mexico reveal that G. aetherium is adventive in North America.

Molecular mapping of resistance to Leptosphaeria maculans in Australian cultivars of Brassica napus

Genome ◽  
1997 ◽  
Vol 40 (3) ◽  
pp. 294-301 ◽  
Author(s):  
R. Mayerhofer ◽  
A. G. Good ◽  
V. K. Bansal ◽  
M. R. Thiagarajah ◽  
G. R. Stringam
Keyword(s):  
Brassica Napus ◽  
Molecular Mapping ◽  
Bulked Segregant Analysis ◽  
Leptosphaeria Maculans ◽  
Rflp Markers ◽  
Dh Population ◽  
Dna Mapping ◽  
Resistant Varieties ◽  
Dh Lines ◽  
Blackleg Fungus

Doubled haploid (DH) lines together with a cotyledon bioassay were employed for the molecular analysis of resistance to the blackleg fungus Leptosphaeria maculans in the Australian Brassica napus cultivars Shiralee and Maluka. We used bulked segregant analysis to identify 13 RAPD and two RFLP markers linked to the resistance phenotype and mapped these markers in the segregating DH population. Our data suggest the presence of a single major locus controlling resistance in the cultivar Shiralee, confirming our previous results obtained from Mendelian genetic analyses. In addition, preliminary mapping data for the cultivar Maluka also support a single locus model for resistance and indicate that the resistance genes from 'Shiralee' and 'Maluka' are either linked or possibly identical. The molecular markers identified in this study should be a useful tool for breeding blackleg resistant varieties using marker-assisted selection, and are the essential first step towards the map-based cloning of this resistance gene.Key words: blackleg, Leptosphaeria maculans, Brassica napus, DNA mapping, disease resistance.

Determination of the origin of the cold-adapted populations of barnyard grass (Echinochloa crus-galli) in eastern North America: a total-evidence approach using RAPD DNA and DNA sequences

2000 ◽  
Vol 78 (12) ◽  
pp. 1505-1513 ◽  
Author(s):  
Sophie Roy ◽  
Jean-Pierre Simon ◽  
François-Joseph Lapointe
Keyword(s):  
North America ◽  
Dna Sequences ◽  
North American ◽  
Western Europe ◽  
Random Amplified Polymorphic Dna ◽  
Molecular Techniques ◽  
Total Evidence ◽  
Eastern Canada ◽  
Barnyard Grass ◽  
Cold Adapted

This survey attempts to establish the origin of cold-adapted populations of barnyard grass (Echinochloa crus-galli (L.) Beauv.) in North America using molecular techniques, including random amplified polymorphic DNA (RAPD) and two types of sequences: chloroplast intron (trnL (UAA)) and rDNA nuclear spacer (ITS 1). There exists many possible scenarios to explain the origin of E. crus-galli in eastern Canada (Quebec), but we dwelled on two particular hypotheses, which are not mutually exclusive. The first hypothesis stipulates that the populations originated only from Europe, whereas the second implies that native subtropical and warm-temperate populations migrated from the south towards northern regions. To assess the likelihood of these hypotheses, the genetic distance matrices obtained from RAPD markers, nuclear, and chloroplastic sequences were combined and tested against the competing models. A principal coordinate analysis was used to discriminate among populations sampled from three different regions (i.e., Quebec, American east coast, and western Europe) and an analysis of molecular variance (AMOVA) detected a significant genetic structure among these populations (FST = 0.110, p < 0.05). Pairwise comparisons further indicated that European populations were significantly different from all other populations, whereas North American populations were not different from one another. The combined sequences revealed eight different haplotypes. Six populations were characterized by unique haplotypes, while one haplotype was shared by 3 of the 12 North American populations. The last and most common haplotype was observed in 9 of the 18 populations from all three regions. The tests computed thus supported the second hypothesis suggesting that the cold-adapted populations of eastern Canada are probably derived from other North American populations rather than European populations.Key words: AMOVA, RAPD, rDNA, cpDNA, genetic variation, population structure.

scholarly journals Clustering Analysis and Genome Inference of Pisang Raja Local Cultivars (Musa spp.) from Java Island by Random Amplified Polymorphic DNA (RAPD) Marker

2019 ◽  
Vol 4 (2) ◽  
pp. 42 ◽  
Author(s):  
Rasyadan Taufiq Probojati ◽  
Didik Wahyudi ◽  
Lia Hapsari
Keyword(s):  
Genetic Diversity ◽  
Rapd Markers ◽  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Molecular Techniques ◽  
Principal Coordinates Analysis ◽  
Local Cultivars ◽  
Principal Coordinates ◽  
Polymorphic Bands ◽  
Cluster 2

Pisang Raja is an important local banana cultivar in the economy and cultural life in Indonesia, especially at Java. There are many Pisang Raja cultivars found on Java Island with various local names in each region, resulted in problems on taxonomic identification and grouping. Conventional research for grouping banana cultivars is still using morphological characters but considered inaccurate because of its subjectivity. This study aims to analyze the genetic diversity, grouping, and genome estimation of 13 local cultivars of Pisang Raja based on molecular approach using RAPD markers (OPA primers 1-20). Clustering and Principal Coordinates Analysis were performed to the amplified products using Paleontological Statistics (PAST) application version 3.15. Results showed that there were 12 primers which successfully amplified and produced DNA polymorphic bands in Pisang Raja, specifically OPA 1, OPA 2, OPA 3, OPA 4, OPA 5, OPA 8, OPA 16, OPA 17, OPA 18, OPA 19, and OPA 20. Pisang Raja cultivars considered have high genetic diversity, indicated by high polymorphic bands (95.17%) and low similarity coefficient values (0.2-0.6). Clustering and PCo analysis resulted in 3 clusters following its genomic group consist of AAA, AAB and ABB genomes, with Pisang Raja Bali as an outgroup (ABB). However, the separation of each cluster for genome inference was unclear. Cluster 1 consists of Pisang Raja Madu (AAB) and Raja Sereh (AAB). Cluster 2 consists of AAA and AAB genomes; includes Pisang Raja Jambe (AAA), Raja Kriyak (AAA), Raja Kutuk (AAB), Raja Brentel (AAB), Raja Seribu (AAB), and Raja Lini (AAB). Cluster 3 consists of AAA and AAB genomes, includes Pisang Raja Kisto (AAA), Raja Delima (AAA), Raja Bandung (AAB) and Raja Gareng (AAB). While Pisang Monyet (AAw) and Klutuk Wulung (BBw) as wild relatives were nested in Cluster 2. There were some different results of genome estimation based on RAPD markers compared to morphological characterization, and other molecular techniques. The use of RAPD markers is quite efficient and effective for studying genetic diversity and identifying genomes in bananas.

scholarly journals Morphological and molecular studies of three species of Boerhavia L. from Ile-Ife, Nigeria

2020 ◽  
Vol 22 (2) ◽  
pp. 225-236
Author(s):  
S.O. Azeez ◽  
J.O. Matthew ◽  
E.A. Olaoluwa ◽  
G.B. Adegboyega ◽  
I.O. Akinyoola
Keyword(s):  
Cluster Analysis ◽  
Phylogenetic Relationship ◽  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Pollen Grains ◽  
Morphological Characters ◽  
Morphological Data ◽  
Group Method ◽  
Wide Range ◽  
High Level

A wide range of plasticity and polymorphism have been documented in the genus Boerhavia. More so, the possible presence of natural hybrids  among the species of the genus has made species identification more difficult. This study employed morphological characters, pollen parameters as well as Random Amplified Polymorphic DNA (RAPD) to identify and elucidate the phylogenetic relationship that exists among the three species of Boerhavia distributed in Ile-Ife, Nigeria. Qualitative and quantitative morphological characters were observed and measured respectively. The acetolysis of the pollen grains was carried out according to Erdtman method. Fresh and young leaves of the Boerhavia species studied were  collected for genomic DNA extraction using modified Dellarpota procedure. The quality and concentration of DNA was assessed by gel electrophoresis on 2% agarose with known concentrations of undigested lambda DNA. Subsequently, the DNA quantification was done according to standard measurement. The Principal Components Analysis of the morphological traits and the pollen grain studies indicated that the three Boerhavia species studied have a very high level of relationship. However, the Single Linkage Cluster Analysis of the morphological data and the unweighted pair group method with arithmetic mean (UPGMA) cluster analysis of RAPD data revealed that B. erecta is distantly related to B. coccinea and B. diffusa. Despite the fact that the three Boerhavia species studied possess high level of similarity, they can still be distinguished from each other. In conclusion, B. coccinea and B. diffusa are more closely related to each other than B. erecta. Key words: RAPD marker, Pollen grains, Phylogenetic relationship, Polymorphism

scholarly journals Genetic Variability and Relationships among Thirty Genotypes of Finger Millet (Eleusine coracana L. Gaertn.) Using RAPD Markers

2007 ◽  
Vol 62 (1-2) ◽  
pp. 116-122 ◽  
Author(s):  
Swanalata Das ◽  
Rama Chandra Mishra ◽  
Gyana Ranjan Rout ◽  
Subhashree Aparajita
Keyword(s):  
Finger Millet ◽  
Random Amplified Polymorphic Dna ◽  
Rapd Marker ◽  
Plant Genetic Resources ◽  
Morphological Characters ◽  
Similarity Coefficient ◽  
Eleusine Coracana ◽  
Leaf Architecture ◽  
Genotype I ◽  
Major Cluster

Ragi or finger millet (Eleusine coracana L.) is an important crop used for food, forage, and industrial products. It is distributed in tropical and temperate regions of the world. The germplasm identification and characterization is an important link between the conservation and utilization of plant genetic resources. Traditionally, species or varieties identification has relied on morphological characters like growth habit, leaf architecture or floral morphology. Investigation through RAPD (random amplified polymorphic DNA) markers was undertaken for identification and determination of the genetic variation among thirty genotypes of ragi of the family Poaceae. Thirteen selected decamer primers were used for genetic analysis. A total of 124 distinct DNA fragments ranging from 300-3000 bp was amplified by using selected random RAPD marker. The genetic similarity was evaluated on the basis of the presence or absence of bands. Cluster analysis was made by the similarity coefficient. It indicated that the 30 genotypes of ragi form two major clusters, first, a major cluster having only one genotype, i. e. Dibyasinha and a second major cluster having twenty-nine genotypes. The second major cluster again subdivides into two minor clusters. A first minor cluster has only three varieties, i. e. Neelachal, OEB-56 and Chilika. The genotypes Neelachal and OEB- 56 exhibit a 86% similarity with each other and 80% similarity with Chilika. A second minor cluster has 26 genotypes and is divided into two sub-minor clusters. The first sub-minor cluster has only one genotype (VL-322). The second sub-minor cluster again subdivides into two groups. One group has one genotype and the second group again is divided into two sub-groups, one with 13 genotypes and the other with 11 genotypes. The highest similarity coefficient was detected in a genotype collected from southern India and the least from northern India. The genotypes of finger millet collected from diverse agroclimatic regions of India constitute a wide genetic base. This is helpful in breeding programs and a major input into conservation biology of cereal crop.

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