scholarly journals New Hybrid Strains via Intraspecific Protoplast Fusion of the Entomopathogenic Fungi Lecanicillium spp.

2021 ◽  
Vol 50 (6) ◽  
pp. 1639-1650
Author(s):  
Liang Liu ◽  
Chunlai Liu ◽  
Lili Yan ◽  
Fan Yang ◽  
Shuang Wang ◽  
...  
Keyword(s):  
Protoplast Fusion ◽  
Dna Analysis ◽  
Genetic Recombination ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characteristics ◽  
Verticillium Lecanii ◽  
Biological Control Agents ◽  
Median Lethal Concentration ◽  
Highly Pathogenic ◽  
Nit Mutants

The entomopathogenic fungal genus Lecanicillium Gams and Zare (formerly classified as the species Verticillium lecanii) includes species that are highly pathogenic to many insect genera. In this study, we identified six Lecanicilliumspp. isolated strains (designated as V1-V6) belonging to L. lecanii (V1, V3 and V5) and L. attenuatum (V2, V4 and V6). In addition, these strains were used to obtain new strains via protoplast fusion, and nit mutants were used for protoplast selection. Genetic recombination of the hybrid strains was determined using the random amplified polymorphic DNA(RAPD) technique. We obtained nine stable fusant strains from 176 new hybrid strains, which were termed V12-10, V14-3, V16-4, V23-6, V25-8, V34-14, V36-5, V45-16 and V56-7. Morphological characteristics varied between the hybrid and parental strains. Genomic DNA analysis of the fusants also showed genetic recombination. The median lethal concentration (LC50) for the fusants were lower than that for parental strains, and the median survival time (LT50) for the fusants were reduced compared with that for parental strains. Thus, these results showed that we produced new, more virulent hybrid Lecanicillium spp. strainsas biological control agents via intraspecific protoplast fusion.

Identification of Aspergillus flavus Isolates as Potential Biocontrol Agents of Aflatoxin Contamination in Crops

2013 ◽  
Vol 76 (6) ◽  
pp. 1051-1055 ◽  
Author(s):  
L. J. ROSADA ◽  
J. R. SANT'ANNA ◽  
C. C. S. FRANCO ◽  
G. N. M. ESQUISSATO ◽  
P. A. S. R. SANTOS ◽  
...  
Keyword(s):  
Biological Control ◽  
Aspergillus Flavus ◽  
Filamentous Fungus ◽  
Microscopic Examination ◽  
Genetic Recombination ◽  
Aflatoxin Contamination ◽  
Biocontrol Agents ◽  
Biological Control Agents ◽  
Nit Mutants ◽  
The Stability

Aspergillus flavus, a haploid organism found worldwide in a variety of crops, including maize, cottonseed, almond, pistachio, and peanut, causes substantial and recurrent worldwide economic liabilities. This filamentous fungus produces aflatoxins (AFLs) B1 and B2, which are among the most carcinogenic compounds from nature, acutely hepatotoxic and immunosuppressive. Recent efforts to reduce AFL contamination in crops have focused on the use of nonaflatoxigenic A. flavus strains as biological control agents. Such agents are applied to soil to competitively exclude native AFL strains from crops and thereby reduce AFL contamination. Because the possibility of genetic recombination in A. flavus could influence the stability of biocontrol strains with the production of novel AFL phenotypes, this article assesses the diversity of vegetative compatibility reactions in isolates of A. flavus to identify heterokaryon self-incompatible (HSI) strains among nonaflatoxigenic isolates, which would be used as biological controls of AFL contamination in crops. Nitrate nonutilizing (nit) mutants were recovered from 25 A. flavus isolates, and based on vegetative complementation between nit mutants and on the microscopic examination of the number of hyphal fusions, five nonaflatoxigenic (6, 7, 9 to 11) and two nontoxigenic (8 and 12) isolates of A. flavus were phenotypically characterized as HSI. Because the number of hyphal fusions is reduced in HSI strains, impairing both heterokaryon formation and the genetic exchanges with aflatoxigenic strains, the HSI isolates characterized here, especially isolates 8 and 12, are potential agents for reducing AFL contamination in crops.

Hybrid origin of Athrotaxis laxifolia (Taxodiaceae) confirmed by random amplified polymorphic DNA analysis

2000 ◽  
Vol 48 (6) ◽  
pp. 753 ◽  
Author(s):  
Keiya Isoda ◽  
Tim Brodribb ◽  
Susumu Shiraishi
Keyword(s):  
Dna Analysis ◽  
Genetic Relationships ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Single Strand Conformation Polymorphism ◽  
Hybrid Origin ◽  
Pollen Donor ◽  
Atpa Gene ◽  
D Values

Random amplified polymorphic DNA (RAPD) and single-strand conformation polymorphism (SSCP) analyses were employed for investigating genetic relationships of three Athrotaxis D.Don species. Twenty-nine RAPD primers produced 103 polymorphic bands. Principal component analysis revealed the genomic differentiation among three Athrotaxis species. Mean genetic distance (mean d) between A. selaginoides D.Don and A. cupressoides D.Don was 0.89. Mean d values were reduced to 0.42/0.54 between A. laxifolia Hook. and A. selaginoides/A. cupressoides, respectively. Intraspecific mean d of A. selaginoides and A. cupressoides were, respectively, 0.03 and 0.11. These values indicated that A. laxifolia, which is regarded as a hybrid between A. selaginoides and A. cupressoides, is genetically intermediate between A. selaginoides and A. cupressoides. This genetic characteristic and previously reported morphological characteristics suggest the hybrid origins of A. laxifolia. The genomic composition of A. laxifolia was estimated by the number of bands specific to A. selaginoides or A. cupressoides in order to determine the genomic contribution of these two species to its proposed hybrid, A. laxifolia. All of the five individuals investigated herein possessed genomes derived almost evenly from A. selaginoides and A. cupressoides. Furthermore, the pollen donor of A. laxifolia was determined by SSCP analysis of the atpA gene on chloroplast DNA. Because all of the five A. laxifolia possessed the A. selaginoides-type chloroplast genome, A. laxifolia would be a hybrid of A. selaginoides as a paternal parent and A. cupressoides as a maternal parent.

scholarly journals Description of three new arctic bramble cultivars and proposal for cultivar identification

1998 ◽  
Vol 7 (4) ◽  
pp. 455-468 ◽  
Author(s):  
H. PIRINEN ◽  
P. DALMAN ◽  
S. KÄRENLAMPI
Keyword(s):  
Dna Analysis ◽  
Cultivar Identification ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characteristics ◽  
Growing Season ◽  
The Arctic ◽  
New Cultivars

Morphological and yield differences between five arctic bramble (Rubus arcticus L.) strains and the cultivars Pima and Mespi were studied at two locations during the growing season 1994. Morphological observations and measurements were made on canes, leaves, flowers and berries, adapting the UPOV (Union pour la Protection des Obtentions Vegetales) descriptions for strawberry and raspberry. The plants were also compared with the aid of random amplified polymorphic DNA analysis. Apart from DNA, the most important distinctive characteristic was yield. Characteristics of the flowers, leaves and berries, such as number, size, shape and colour were used to differentiate between the arctic bramble genotypes. The yield of three new cultivars, named Marika, Muuruska and Elpee, was greater than that of Pima or Mespi. The yield of 'Marika' and 'Elpee' was 2,4-times and that of 'Muuruska' 1,9-times that of 'Pima' or 'Mespi'. Based on distinctive morphological characteristics, guidelines for the description of arctic bramble are proposed. This description may also be used for hybrids of arctic bramble with Rubus stellatus Sm., i.e. Rubus arcticus L. nothosubsp. stellarcticus G. Larsson. ;

scholarly journals First Report of a New Race of Sunflower Broomrape (Orobanche cumana) in Israel

Plant Disease ◽  
2004 ◽  
Vol 88 (11) ◽  
pp. 1284-1284 ◽  
Author(s):  
H. Eizenberg ◽  
D. Plakhine ◽  
T. Landa ◽  
G. Achdari ◽  
D. M. Joel ◽  
...  
Keyword(s):  
Dna Analysis ◽  
Local Development ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characteristics ◽  
Intraspecific Diversity ◽  
Plant Management ◽  
Resistance Response ◽  
Orobanche Cumana ◽  
Sunflower Broomrape ◽  
New Race

The genus Orobanche includes chlorophyll-lacking root parasites that parasitize many dicotyledonous species and causes severe damage to vegetable and field crops worldwide. Sunflower broomrape (Orobanche cumana Wallr.) is known in Eurasia as a specific parasite of sunflower, which differs from the nodding broomrape (O. cernua Loefl) in host specificity and morphological characteristics (3). Together with Egyptian broomrape (O. aegyptiaca Pers.), it seriously parasitizes sunflower (Helianthus annuus L.) in Israel (1). Prior to 2000, the local confectionary sunflower cvs. Ambar and Gitit proved to be resistant to the local O. cumana populations in Israel (2). A preliminary study, which we conducted in 1995 using the Vranceanu's differentials (4), indicated that O. cumana populations in Israel behave like the known race C. Using random amplified polymorphic DNA analysis, we also found a very low intraspecific diversity of this species in Israel at that time. However, in 2000, infection of the sunflower cvs. Ambar and Gitit was reported in two fields (Gadot and Afek) in northern Israel. In 2001 and 2002, O. cumana parasitized these cultivars in three more locations as much as 50 km apart (Tel-Adashim, Mevo-Hama, and Bet-Hilel). To determine the virulence of O. cumana populations on sunflower cultivars under controlled conditions, O. cumana seeds were collected in the above mentioned sunflower fields. In addition, we also used seeds from an O. cumana population collected in Alonim in 1997. This latter population did not infect the above mentioned ‘resistant’ sunflower cultivars in the field (2,); therefore, represented the previously known O. cumana populations in Israel. Resistant (Ambar) and susceptible (D.Y.3) sunflower cultivars were planted in separate pots that were differentially filled with soil that was inoculated with O. cumana seeds of the different populations. The experiment was performed in a full factorial arrangement with six replications. As expected, O. cumana from Alonim failed to attack the resistant sunflower. However, the O. cumana populations that were collected in the five other fields seriously attacked both sunflower cultivars, indicating higher virulence. O. cumana from all five new populations proved more virulent than the Alonim population on cvs. Ambar and D.Y.3. The occurrence of these new virulent populations could have several reasons including: (i) importation of virulent parasite seeds from abroad; or (ii) local development of virulence from previously avirulent populations. The latter could be favored by the continuous and repeated use of the available resistant varieties that are all based on a single resistance response (2). References: (1) H. Eizenberg and D. M. Joel. Orobanche in Israeli agriculture. Workshop of COST Action 849, Parasitic Plant Management in Sustainable Agriculture, 2001. (2) H. Eizenberg et al. Plant Dis. 88:479, 2003. (3) D. M. Joel. Phytoparasitica 16:375, 1988. (4) A. V. Vranceanu et al. Proc. 9th Sunflower Conf. 1:74–82, 1980.

scholarly journals SNP and SCAR Markers for Specific Discrimination of Antler-Shaped Ganoderma lucidum

2019 ◽  
Vol 7 (1) ◽  
pp. 12 ◽  
Author(s):  
O-Chul Kwon ◽  
Chang-Soo Lee ◽  
Young-Jin Park
Keyword(s):  
Ganoderma Lucidum ◽  
Gene Sequence ◽  
Rapd Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Morphological Characteristics ◽  
Pcr Analysis ◽  
Scar Markers ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Specific Fragment

In this study we identified single nucleotide polymorphism (SNP) and sequence characteristic amplification region (SCAR) markers for specific identification of antler-shaped Ganoderma lucidum strains. When the partial mitochondrial SSU rDNA gene sequence of various antler- and kidney-shaped G. lucidum strains were analyzed and aligned, an SNP was found only in the antler-shaped G. lucidum strain at position 456 bp. In addition, this SNP of antler-shaped strains was digested by HinfI restriction enzyme. We further analyzed the polymorphism of various G. lucidum strains by random amplified polymorphic DNA (RAPD) analysis. In RAPD analysis, we isolated and sequenced a fragment, specific for antler-shaped G. lucidum strains. Based on this specific fragment sequence, two sets of specific primer pairs for antler-shaped G. lucidum strains were designed. PCR analysis revealed that two specific bands were observed only from antler-shaped strains. These two molecular markers will be helpful for identification of morphological characteristics of G. lucidum.

scholarly journals Molecular and Pathogenicity Characterization of Sphaceloma manihoticola Isolates from South-Central Brazil

Plant Disease ◽  
2003 ◽  
Vol 87 (11) ◽  
pp. 1322-1328 ◽  
Author(s):  
Elizabeth Alvarez ◽  
Juan Fernando Mejia ◽  
Teresa L. Valle
Keyword(s):  
Morphological Characteristics ◽  
Restriction Pattern ◽  
Poly Merase Chain Reaction ◽  
Highly Pathogenic ◽  
Central Brazil ◽  
Host Interaction ◽  
South Central ◽  
Pcr Product ◽  
Pathogenic Variation

Isolates of Sphaceloma manihoticola, the asexual stage of Elsinoe brasiliensis, were collected from several regions of south-central Brazil. The isolates were obtained from samples of leaves, stems, and petioles of cassava (Manihot esculenta) and the weedy Euphorbia heterophylla (“amendoim bravo”) by directly plating infected tissue onto acidified potato dextrose agar. For pathogenicity studies, 19 isolates were inoculated onto each of two cassava cultivars, MBRA 703 as a susceptible cultivar and MBRA 12 as a resistant cultivar to S. manihoticola. MBRA 703, with the greatest pathogenicity to 58% (11) of the isolates, showed an intermediate pathogenic reaction to 16% (3) of the isolates, and was less pathogenic to 26% (5) of the isolates. MBRA 12, with a less pathogenic reaction to 63% (12) of the isolates, showed an intermediate pathogenic reaction to 16% (3) of the isolates, and was highly pathogenic to 21% (4) of the isolates. The isolates were verified as belonging to the genus Sphaceloma based on their morphological characteristics, including conidia and hyphae of monoconidial isolate. Conidia of isolates were small, thin-walled, ellipsoid to (rarely) globose, commonly with one or two gut-tules. Conidiophores were phialides, hyaline to slightly pigmented 0-to-1 septate; conidiophores from the weedy specie were phialides, hyaline to brown 0-to-2 septate producing hyaline conidia. The isolates also were verified as belonging to the genus Sphaceloma by using a poly-merase chain reaction (PCR) assay, which detected a 645-bp band in all isolates except two (1 and 6) for which the PCR product had 600 bp. Digestion of the amplified product with the enzymes MspI and CfoI allowed differences to be detected in restriction patterns among isolates. A homogeneous banding pattern was obtained for 17 of the isolates but a different restriction pattern was obtained for isolates 1 and 6 of E. heterophylla. This suggests the possibility of another species within this group of isolates. The results indicate the presence of pathogenic variation among isolates of the fungus and an isolate-host interaction, because statistically significant differences were observed between the two cassava cultivars in response to inoculation with the isolates of S. manihoticola.

scholarly journals Two new species of Undifilum, fungal endophytes of Astragalus (locoweeds) in the United States

Botany ◽  
2012 ◽  
Vol 90 (9) ◽  
pp. 866-875 ◽  
Author(s):  
Deana L. Baucom ◽  
Marie Romero ◽  
Robert Belfon ◽  
Rebecca Creamer
Keyword(s):  
New Species ◽  
New Mexico ◽  
Random Amplified Polymorphic Dna ◽  
Phylogenetic Analyses ◽  
Fungal Endophytes ◽  
Morphological Characteristics ◽  
Its Region ◽  
The United States ◽  
Neighbor Joining

New species of Undifilum , from locoweeds Astragalus lentiginosus Vitman and Astragalus mollissimus Torr., are described using morphological characteristics and molecular phylogenetic analyses as Undifilum fulvum Baucom & Creamer sp. nov. and Undifilum cinereum Baucom & Creamer sp. nov. Fungi were isolated from dried plants of A. lentiginosus var. araneosus , diphysus , lentiginosus , and wahweapensis collected from Arizona, Oregon, and Utah, USA, and A. mollissimus var. biglovii , earleii , and mollissimus collected from New Mexico, Oklahoma, and Texas, USA. Endophytic fungi from Astragalus locoweeds were compared to Undifilum oxytropis isolates obtained from dried plant material of Oxytropis lamberteii from New Mexico and Oxytropis sericea from Arizona, Colorado, New Mexico, Utah, and Wyoming. Extremely slow growth in vitro was observed for all, and conidia, if present, were ellipsoid with transverse septa. However, in vitro color, growth on four different media, and conidium size differed between fungi from Astragalus spp. and U. oxytropis. Neighbor-joining analyses of internal transcribed spacer (ITS) region and glyceraldehyde-3-phosphate dehydrogenase (GPD) gene sequences revealed that U. fulvum and U. cinereum formed a clade distinct from U. oxytropis. This was supported by neighbor-joining analyses of results generated from random amplified polymorphic DNA (RAPD) fragments using two different primers.

scholarly journals Analysis of the genetic polymorphism of Paracoccidioides brasiliensis and Paracoccidioides cerebriformis "Moore" by random amplified polymorphic DNA (RAPD) and 28S ribosomal DNA sequencing: Paracoccidioides cerebriformis revisited

2005 ◽  
Vol 47 (3) ◽  
pp. 119-123 ◽  
Author(s):  
Sarah Desirée Barbosa Cavalcanti ◽  
José Eduardo Levi ◽  
Kátia Cristina Dantas ◽  
José Eduardo Costa Martins
Keyword(s):  
Genetic Polymorphism ◽  
Dna Sequence ◽  
Ribosomal Dna ◽  
Dna Analysis ◽  
Paracoccidioides Brasiliensis ◽  
Random Amplified Polymorphic Dna ◽  
Distinct Species ◽  
De Medicina ◽  
28S Ribosomal Dna ◽  
Mycological Laboratory

Our purpose was to compare the genetic polymorphism of six samples of P. brasiliensis (113, 339, BAT, T1F1, T3B6, T5LN1), with four samples of P. cerebriformis (735, 741, 750, 361) from the Mycological Laboratory of the Instituto de Medicina Tropical de São Paulo, using Random Amplified Polymorphic DNA Analysis (RAPD). RAPD profiles clearly segregated P. brasiliensis and P. cerebriformis isolates. However, the variation on band patterns among P. cerebriformis isolates was high. Sequencing of the 28S rDNA gene showed nucleotide conservancy among P. cerebriformis isolates, providing basis for taxonomical grouping, and disclosing high divergence to P. brasiliensis supporting that they are in fact two distinct species. Moreover, DNA sequence suggests that P. cerebriformis belongs in fact to the Aspergillus genus.

scholarly journals Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs)

1999 ◽  
Vol 41 (5) ◽  
pp. 291-295 ◽  
Author(s):  
Abdel-Hamid Zaki ABDEL-HAMID ◽  
Jeanne Blanco de MOLFETTA ◽  
Vania FERNANDEZ ◽  
Vanderlei RODRIGUES
Keyword(s):  
Dna Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Polyacrylamide Gel Electrophoresis ◽  
Genome Comparison ◽  
Gene Products ◽  
Chain Reaction ◽  
High Molecular Weight Dna ◽  
Polymerase Chain ◽  
Or Gene ◽  
Host Parasite

Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers) were used to amplify the extracted DNA by the polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis (PAGE) and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.

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