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Sample records for mycoherbicides

  1. Evaluation of toxicity of Cercospora piaropi in a mycoherbicide formulation by using bacterial bioluminescence and the Ames mutagenicity tests.

    PubMed

    Jiménez, Maricela Martínez; Villasana, Ana María Sandoval

    2009-04-01

    An evaluation of the potential hazards associated with mutagenicity and acute toxicity of a mycoherbicide formulation based on the fungal pathogen Cercospora piaropi was performed. Neither the mycoherbicide nor any of its components were mutagenic to Salmonella typhimurium TA98 and TA100 with or without metabolic activation. Both the C. piaropi and the mycoherbicide formulation were shown to be moderately toxic with a bacterial bioluminescence assay. No acute toxicity was found in water samples taken from tanks after treatment of water hyacinth with the mycoherbicide.

  2. Mycoherbicidal Potential of Phaeoacremonium italicum, A New Pathogen of Eichhornia crassipes Infesting Harike Wetland, India

    PubMed Central

    Singh, Birinderjit; Meshram, Vineet; Kumar, Maneek

    2016-01-01

    Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth. PMID:27433118

  3. Mycoherbicidal Potential of Phaeoacremonium italicum, A New Pathogen of Eichhornia crassipes Infesting Harike Wetland, India.

    PubMed

    Singh, Birinderjit; Saxena, Sanjai; Meshram, Vineet; Kumar, Maneek

    2016-06-01

    Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth.

  4. Pyrenophoric acid, a phytotoxic sesquiterpenoid penta-2,4-dienoic acid produced by a potential mycoherbicide, Pyrenophora semeniperda

    Treesearch

    Marco Masi; Susan Meyer; Alessio Cimmino; Anna Andolfi; Antonio Evidente

    2014-01-01

    A new phytotoxic sesquiterpenoid penta-2,4- dienoic acid, named pyrenophoric acid, was isolated from solid wheat seed culture of Pyrenophora semeniperda, a fungal pathogen proposed as a mycoherbicide for biocontrol of cheatgrass (Bromus tectorum) and other annual bromes. These bromes are serious weeds in winter cereals and also on temperate semiarid rangelands....

  5. Effect of strain and cultural conditions on the production of cytochalasin B by the potential mycoherbicide Pyrenophora semeniperda (Pleosporaceae, Pleosporales)

    Treesearch

    Marco Masi; Antonio Evidente; Susan Meyer; Joshua Nicholson; Ashley. Munoz

    2014-01-01

    The seed pathogen Pyrenophora semeniperda has demonstrated potential as a mycoherbicidal biocontrol for eliminating persistent seed banks of annual bromes on western North American rangelands. This pathogen exhibits variation in virulence that is related to mycelial growth rate, but direct laboratory tests of virulence on seeds often have low repeatability. We...

  6. Ultralow calcium requirements of fungi facilitate use of calcium regulating agents to suppress host calcium-dependent defenses, synergizing infection by a mycoherbicide.

    PubMed

    Gressel, Jonathan; Michaeli, Daphna; Kampel, Vladimir; Amsellem, Ziva; Warshawsky, Abraham

    2002-10-23

    Infection by many fungi activates a variety of calcium dependent defenses in the hosts, slowing or suppressing the attacker and limiting the efficacy of mycoherbicides. The calcium requirement for fungal growth is so low that it could only be implied based on fungi containing calcium-dependent signaling enzymes. Analytical grade media contain <2 microM calcium, and the addition of specific chelators does not affect fungal growth. Hydrophobic derivatives of the calcium-specific chelator BAPTA designed to traverse plant cuticles were synthesized in order to chelate calcium internally during fungal attack. Some chelators as well as calcium precipitating oxalate and channel blocker verapamil were applied with a weakly mycoherbicidal Colletotrichum coccodes to cotyledons of compatible Abutilon threophrasti. They suppressed calcium dependent callose biosynthesis in the weed and increased virulence but may have affected other calcium-dependent processes that facilitate virulence. The low calcium requirement of fungi, and their high affinity for calcium, allows the application of calcium-regulating agents as synergists for mycoherbicides where the weed uses calcium-dependent defenses.

  7. Pyrenophoric acid, a phytotoxic sesquiterpenoid penta-2,4-dienoic acid produced by a potential mycoherbicide, Pyrenophora semeniperda.

    PubMed

    Masi, Marco; Meyer, Susan; Cimmino, Alessio; Andolfi, Anna; Evidente, Antonio

    2014-04-25

    A new phytotoxic sesquiterpenoid penta-2,4-dienoic acid, named pyrenophoric acid, was isolated from solid wheat seed culture of Pyrenophora semeniperda, a fungal pathogen proposed as a mycoherbicide for biocontrol of cheatgrass (Bromus tectorum) and other annual bromes. These bromes are serious weeds in winter cereals and also on temperate semiarid rangelands. Pyrenophoric acid was characterized as (2Z,4E)-5-[(7S,9S,10R,12R)-3,4-dihydroxy-2,2,6-trimethylcyclohexyl)]-3-methylpenta-2,4-dienoic acid by spectroscopic and chemical methods. The relative stereochemistry of pyrenophoric acid was assigned using 1H,1H couplings and NOESY experiments, while its absolute configuration was determined by applying the advanced Mosher's method. Pyrenophoric acid is structurally quite closely related to the plant growth regulator abscisic acid. When bioassayed in a cheatgrass coleoptile elongation test at 10(-3) M, pyrenophoric acid showed strong phytotoxicity, reducing coleoptile elongation by 51% relative to the control. In a mixture at 10(-4) M, its negative effect on coleoptile elongation was additive with that of cytochalasin B, another phytotoxic compound found in the wheat seed culture extract of this fungus, demonstrating that the extract toxicity observed in earlier studies was due to the combined action of multiple phytotoxic compounds.

  8. Presence of adhesive vesicles in the mycoherbicide Alternaria helianthi

    USDA-ARS?s Scientific Manuscript database

    Alternaria helianthi conidia have been shown to cause disease on common cocklebur. Conidia were applied to slides made hydrophobic by coating with dimethyldicholorosilane (mimics leaf surface), then rinsed and treated with FITC-Con A to stain the adhesive material. Alternaria helianthi coni...

  9. Phyllostictines A-D, Oxazatricycloalkenones Produced by Phyllosticta cirsii, A Potential Mycoherbicide for Cirsium arvense Biocontrol

    USDA-ARS?s Scientific Manuscript database

    Phyllosticta cirsii, a fungal pathogen isolated from Cirsium arvense and proposed as biocontrol agent of this noxious perennial weed, produces in liquid cultures different phytotoxic metabolites with potential herbicidal activity. Four new oxazatricycloalkenones, named phyllostictines A-D, were isol...

  10. Alternethanoxins A and B, polycyclic ethanones produced by Alternaria sonchi , potential mycoherbicides for Sonchus arvensis biocontrol.

    PubMed

    Evidente, Antonio; Punzo, Biancavaleria; Andolfi, Anna; Berestetskiy, Alexander; Motta, Andrea

    2009-08-12

    Alternaria sonchi is a fungal pathogen isolated from Sonchus arvensis and proposed as a biocontrol agent of this noxious perennial weed. Different phytotoxic metabolites were isolated from solid culture of the fungus. Two new polycyclic ethanones, named alternethanoxins A and B, were characterized using essentially spectroscopic and chemical methods. Tested by leaf disk-puncture assay on the fungal host plant and a number of nonhost plants, alternethanoxins A and B were shown to be phytotoxic, whereas they did not possess antimicrobial activity tested at 100 microg/disk. Hence, alternethanoxins A and B have potential as nonselective natural herbicides. Some structure-activity relationship observations were also made.

  11. Phomentrioloxin: A phytotoxic pentasubstituted geranylcyclohexentriol produced by Phomopsis sp., a potential mycoherbicide for Carthamus lanatus Biocontrol.

    PubMed

    Cimmino, Alessio; Andolfi, Anna; Zonno, Maria C; Troise, Ciro; Santini, Antonello; Tuzi, Angela; Vurro, Maurizio; Ash, Gavin; Evidente, Antonio

    2012-06-22

    A new phytotoxic geranylcyclohexenetriol, named phomentrioloxin, was isolated from the liquid culture of Phomopsis sp., a fungal pathogen proposed for the biological control of Carthamus lanatus, a widespread and troublesome thistle weed belonging to the Asteraceae family causing severe crop and pastures losses in Australia. The structure of phomentrioloxin was established by spectroscopic, X-ray, and chemical methods as (1S,2S,3S,4S)-3-methoxy-6-(7-methyl-3-methylene-oct-6-en-1-ynyl)cyclohex-5-ene-1,2,4-triol. At a concentration of 6.85 mM, the toxin causes the appearance of necrotic spots when applied to leaves of both host and nonhost plants. It also causes growth and chlorophyll content reduction of fronds of Lemna minor and inhibition of tomato rootlet elongation. Finally, in preliminary bioassays, phomentrioloxin did not show any antibacterial, fungicidal, or zootoxic activities.

  12. Spirostaphylotrichin W, a spirocyclic γ-lactam isolated from liquid culture of Pyrenophora semeniperda, a potential mycoherbicide for cheatgrass (Bromus tectorum) biocontrol

    Treesearch

    Marco Masia; Susan Meyer; Suzette Clement; Anna Andolfi; Alessio Cimmino; Antonio. Evidente

    2014-01-01

    A novel spirocyclic γ-lactam, named spirostaphylotrichin W (1), was isolated together with the well known and closely related spirostaphylotrichins A, C, D, R and V, as well as triticone E, from the liquid cultures of Pyrenophora semeniperda (anamorph: Drechslera), a seed pathogen proposed for cheatgrass (Bromus tectorum) biocontrol. Spirostaphylotrichin W was...

  13. Pilot-scale production and stabilization of microsclerotia of the potential mycoherbicide Mycoleptodiscus terrestris using deep-tank fermentation and air-drying.

    USDA-ARS?s Scientific Manuscript database

    The fungus Mycoleptodiscus terrestris (Mt) is being developed as a bioherbicide for control of various invasive submersed aquatic plants including Hydrilla verticillata and Myriophyllum spicatum. A constraint to the commercial use of Mt as a bioherbicide is the development of an economic method for...

  14. Papyracillic acid, a phytotoxic 1,6-dioxaspiro[4,4]nonene produced by Ascochyta agropyrina Var. nana, a potential mycoherbicide for Elytrigia repens biocontrol.

    PubMed

    Evidente, Antonio; Berestetskiy, Alexander; Cimmino, Alessio; Tuzi, Angela; Superchi, Stefano; Melck, Dominique; Andolfi, Anna

    2009-12-09

    A strain of Ascochyta agropyrina var. nana was isolated from Elytrigia repens (quack grass), a noxious perennial weed widespread through the cold regions of the northen and southern hemispheres. Papyracillic acid was isolated for the first time from the fungal solid culture and identified using spectroscopic methods, including X-ray diffractometric and CD analysis for the assignment of the relative and absolute stereochemistries. Some key derivatives were prepared and used in a structure-activity relationship study. Tested by leaf disk-puncture assay, papyracillic acid at the concentration of 1 mg/mL was shown to be phytotoxic both for the host plant and a number of nonhost plants of the fungus. Papyracillic acid was active against bacteria (Xanthomonas campestris and Bacillus subtilis) and the fungus Candida tropicalis at 6 microg/disk. Derivatives of papyracillic acid were significantly less active than original toxin. However, the monoacetyl derivative of the toxin did not possess antimicrobial activity but remained highly phytotoxic to quack grass. Hence, papyracillic acid and its analogues have potential as nonselective herbicides of natural origin. Some structure-activity relationship observations for papyracillic acid and its derivatives were also made.

  15. Gulypyrones A and B and Phomentrioloxins B and C Produced by Diaporthe gulyae, a Potential Mycoherbicide for Saffron Thistle (Carthamus lanatus).

    PubMed

    Andolfi, Anna; Boari, Angela; Evidente, Marco; Cimmino, Alessio; Vurro, Maurizio; Ash, Gavin; Evidente, Antonio

    2015-04-24

    A virulent strain of Diaporthe gulyae, isolated from stem cankers of sunflower and known to be pathogenic to saffron thistle, has been shown to produce both known and previously undescribed metabolites when grown in either static liquid culture or a bioreactor. Together with phomentrioloxin, a phytotoxic geranylcyclohexenetriol recently isolated from a strain of Phomopsis sp., two new phytotoxic trisubstituted α-pyrones, named gulypyrones A and B (1 and 2), and two new 1,O- and 2,O-dehydro derivatives of phomentrioloxin, named phomentrioloxins B and C (3 and 4), were isolated from the liquid culture filtrates of D. gulyae. These four metabolites were characterized as 6-[(2S)2-hydroxy-1-methylpropyl]-4-methoxy-5-methylpyran-2-one (1), 6-[(1E)-3-hydroxy-1-methylpropenyl]-4-methoxy-3-methylpyran-2-one (2), 4,6-dihydroxy-5-methoxy-2-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-2-enone (3), and 2,5-dihydroxy-6-methoxy-3-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-3-enone (4) using spectroscopic and chemical methods. The absolute configuration of the hydroxylated secondary carbon of the 2-hydroxy-1-methylpropyl side chain at C-6 of gulypyrone A was determined as S by applying a modified Mosher's method. Other well-known metabolites were also isolated including 3-nitropropionic, succinic, and p-hydroxy- and p-methylbenzoic acids, p-hydroxybenzaldehyde, and nectriapyrone. When assayed using a 5 mM concentration on punctured leaf disks of weedy and crop plants, apart from 3-nitropropionic acid (the main metabolite responsible for the strong phytotoxicity of the culture filtrate), phomentrioloxin B caused small, but clear, necrotic spots on a number of plant species, whereas gulypyrone A caused leaf necrosis on Helianthus annuus plantlets. All other compounds were weakly active or inactive.

  16. Annual brome control using a native fungal seed pathogen

    Treesearch

    Susan E. Meyer; Suzette Clement; Julie Beckstead

    2013-01-01

    Formulations having a selective, mycoherbicide activity for killing ungerminated seeds of invasive grass species are provided. An agricultural, mycoherbicide formulation is taught for killing ungerminated seeds of invasive grass species. The formulations can comprise, for example, a slow-growing strain of Pyrenophora semeniperda, a fast-growing strain of Pyrenophora...

  17. 77 FR 75622 - Notice of Intent to Grant an Exclusive License of the United States; Patent No. 6,569,807

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-21

    ...: CEERD-OT (Ms. Bea Shahin), 2902 Newmark Drive, Champaign, IL 6182-1076. FOR FURTHER INFORMATION CONTACT... INFORMATION: Patent 6,569,807 entitled ``Mycoherbicidal compositions and methods of preparing and using the..., Mycoleptodiscus terrestris, to produce survival propagules termed microsclerotia in fermentation broth culture...

  18. Pyrenophoric acids B and C, two new phytotoxic sesquiterpenoids produced by Pyrenophora semeniperda

    Treesearch

    Marco Masi; Susan Meyer; Alessio Cimmino; Suzette Clement; Beth Black; Antonio Evidente

    2014-01-01

    Two new phytotoxic sesquiterpenoid acids, named pyrenophoric acids B and C, were isolated together with the related pyrenophoric and abscisic acids from solid Bromus tectorum (cheatgrass) seed culture of the seed pathogen Pyrenophora semeniperda. This fungus has been proposed as a mycoherbicide for biocontrol of cheatgrass (Bromus tectorum), a Eurasian annual grass...

  19. Induction of Infection in Sesbania exaltata by Colletotrichum gloeosporioides f. sp. aeschynomene Formulated in an Invert Emulsion

    USDA-ARS?s Scientific Manuscript database

    In greenhouse experiments, an experimental invert emulsion (MSG 8.25) was tested as an adjuvant with spores of the mycoherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene, a highly virulent pathogen of the leguminous weed Aeschynomene virginica (northern jointvetch), but non-pathoge...

  20. Biological control studies on Convolvulus arvensis L. with fungal pathogens

    USDA-ARS?s Scientific Manuscript database

    Field bindweed (Convolvulus arvensis) is a perennial, noxious weed in Europe and in many agricultural areas of the world, including Turkey. Some pathogenic fungi were identified with potential to control bindweed and some of them could be used as mycoherbicide components. In the summers of 2008, 200...

  1. 40 CFR 180.1075 - Colletotrichum gloeosporioides f. sp. aeschynomene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1075 Colletotrichum gloeosporioides f... a tolerance is established for residues of the mycoherbicide Colletotrichum gloeosporioides f. sp. aeschynomene in or on the following raw agricultural commodities: Commodity Aspirated grain fractions...

  2. Aquatic Plant Control Research Program. Biological Control of Hydrilla verticillata (L.f.) Royle with Lytic Enzyme-Producing Microorganisms.

    DTIC Science & Technology

    1985-09-01

    Lytic enzyme-producing microorganisms Biocontrol Mycoherbicides Hydrilla Induced pathogenicity 20. ASTRACT (Coartinue G rev’wm eft if n*..eeam7 mod...However, no natural enemies of hydrilla have yet been imported that are promising biocontrol candidates. Therefore, a less conventional approach was...of microorganisms that function in the decay process. These microorganisms pro- duce enzymes capable of lysing specific plant components such as

  3. [Biological activity of fungi from the phyllosphere of weeds and wild herbaceous plants].

    PubMed

    Berestitskiĭ, A O; Gasich, E L; Poluéktova, E V; Nikolaeva, E V; Sokornova, S V; Khlopunova, L B

    2014-01-01

    Antimicrobial, phytotoxic, and insecticidal activity of 30 fungal isolates obtained from leaves of weeds and wild herbaceous plants was assessed. Antibacterial, antifungal, phytotoxic, and insecticidal activity was found in over 50, 40, 47, and 40% of the isolates, respectively. These findings may be important for toxicological assessment of potential mycoherbicides, as well as provide a basis for investigation of the patterns of development of phyllosphere communities affected by fungal metabolites.

  4. Indole-3-Acetic Acid Biosynthesis in Colletotrichum gloeosporioides f. sp. aeschynomene

    PubMed Central

    Robinson, M.; Riov, J.; Sharon, A.

    1998-01-01

    We characterized the biosynthesis of indole-3-acetic acid by the mycoherbicide Colletotrichum gloeosporioides f. sp. aeschynomene. Auxin production was tryptophan dependent. Compounds from the indole-3-acetamide and indole-3-pyruvic acid pathways were detected in culture filtrates. Feeding experiments and in vitro assay confirmed the presence of both pathways. Indole-3-acetamide was the major pathway utilized by the fungus to produce indole-3-acetic acid in culture. PMID:9835603

  5. Isolation, characterization, and expression of a second {beta}-tubulin-encoding gene from Colletotrichum gloeosporioides f. sp. aeschynomene

    SciTech Connect

    Buhr, T.L.; Dickman, M.B.

    1994-11-01

    Colletotrichum gloeosporioides (Penz.) Sacc. F. sp. aeschynomene incites anthracnose on Aeschynomene virgininica (northern jointvetch). Northern jointvetch is a leguminous weed in rice and soybean fields. Contaminating northern jointvetch seeds greatly reduce the market value of rice. C. gloeosporioides (Penz.) Sacc. F. sp. aeschynomene has been commercially marketed as a mycoherbicide to decrease populations of northern jointvetch. Development of a transformation system would be extremely useful for investigating the molecular biology of C. gloeosporioides (Penz.) Sacc. F. sp. aeschynomen. This paper reports the nucleotide sequence of a second gene for {beta} Tub (TUB2) in C. gloeosporioides (Penz.) Sacc. F. sp. aeschynomene and identifies a molecular lesion which likely confers BEN (systemic fungicide) resistance.

  6. Fungal Phytotoxins with Potential Herbicidal Activity to Control Chenopodium album.

    PubMed

    Cimmino, Alessio; Masi, Marco; Evidente, Marco; Evidente, Antonio

    2015-06-01

    This review deals with the isolation and chemical and biological characterization of phytotoxins produced by Ascochyta caulina and Phoma chenopodiicola proposed as mycoherbicides for the biological control of Chenopodium album, a worldwide spread weed which causes serious problems to some agrarian crops, including sugar beet and maize. Studies on the structure activity relationships and on the modes of actions of toxins isolated are also described, as well as the optimization of analytical methods focused on selection of the best fungal toxin producers. The attempts to scale up production of these phytotoxins aimed to obtain sufficient amounts for their application in greenhouse and field trials are also reported.

  7. Phomentrioloxin, a fungal phytotoxin with potential herbicidal activity, and its derivatives: a structure-activity relationship study.

    PubMed

    Cimmino, Alessio; Andolfi, Anna; Zonno, Maria Chiara; Boari, Angela; Troise, Ciro; Motta, Andrea; Vurro, Maurizio; Ash, Gavin; Evidente, Antonio

    2013-10-09

    Phomentrioloxin is a phytotoxic geranylcyclohexenetriol produced in liquid culture by Phomopsis sp. (teleomorph: Diaporthe gulyae), a potential mycoherbicide proposed for the control of the annual weed Carthamus lanatus. In this study, seven derivatives obtained by chemical modifications of the toxin were assayed for phytotoxic, antimicrobial, and zootoxic activities, and the structure-activity relationships were examined. Each compound was tested on nonhost weedy and agrarian plants, fungi, Gram+ and Gram- bacteria, and on brine shrimp larvae. The results provide insights into an investigation of the structural requirements for activity. The hydroxy groups at C-2 and C-4 appeared to be important features for the phytotoxicity, as well as an unchanged cyclohexentriol ring. A role seemed also to be played by the unsaturations of the geranyl side chain. These findings could be useful for understanding the mechanisms of action of new natural products, for identifying the active sites, and possibly in devising new herbicides of natural origin.

  8. Mycobiota of the weed Conyza canadensis (Asteraceae) in Brazil.

    PubMed

    Duarte, Lidiane Leal; Santos, Fabiana Maria Coutinho; Barreto, Robert Weingart

    2016-09-01

    Conyza canadensis is a noxious and notably problematic weed in Brazil whose control is greatly challenging due to the appearance, in the last years, of herbicide resistant populations. An investigation regarding the associated pathogenic fungi of this plant was conducted in Brazil aimed at starting a biological control program to help mitigate its economic impact. Ten fungal species were yielded and described: two ascomycetes (Leptosphaerulina conyzicola sp. nov. and Wentiomyces melioloides), five hyphomycete asexual morphs (Alternaria tenuissima, Cercospora conyzicola sp. nov., Cercosporella virgaureae, and Fusarium fujikuroi), two coelomycete asexual morphs (Phoma conyzaphthora sp. nov., Septoria erigerontis), one rust fungus (Aecidium conyzicola sp. nov.), and one oomycete (Basidiophora entospora). Four among the fungi that were collected represent new taxa, and the others represented either new host-records of known fungal species or new geographic records or both, except for C. virgaureae that had already been recorded on C. canadensis in Brazil. None of the discovered species have any potential to be used as a mycoherbicide or to be introduced somewhere else, nevertheless, the knowledge about this mycobiota will help guide the selection of potential biocontrol agents to be introduced in Brazil. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. Host-Range Dynamics of Cochliobolus lunatus: From a Biocontrol Agent to a Severe Environmental Threat

    PubMed Central

    Louis, Bengyella; Waikhom, Sayanika Devi; Roy, Pranab; Bhardwaj, Pardeep Kumar; Sharma, Chandradev K.; Singh, Mohendro Wakambam; Talukdar, Narayan Chandra

    2014-01-01

    We undertook an investigation to advance understanding of the host-range dynamics and biocontrol implications of Cochliobolus lunatus in the past decade. Potato (Solanum tuberosum L) farms were routinely surveyed for brown-to-black leaf spot disease caused by C. lunatus. A biphasic gene data set was assembled and databases were mined for reported hosts of C. lunatus in the last decade. The placement of five virulent strains of C. lunatus causing foliar necrosis of potato was studied with microscopic and phylogenetic tools. Analysis of morphology showed intraspecific variations in stromatic tissues among the virulent strains causing foliar necrosis of potato. A maximum likelihood inference based on GPDH locus separated C. lunatus strains into subclusters and revealed the emergence of unclustered strains. The evolving nutritional requirement of C. lunatus in the last decade is exhibited by the invasion of vertebrates, invertebrates, dicots, and monocots. Our results contribute towards a better understanding of the host-range dynamics of C. lunatus and provide useful implications on the threat posed to the environment when C. lunatus is used as a mycoherbicide. PMID:24987680

  10. Differential gene expression for Curvularia eragrostidis pathogenic incidence in crabgrass (Digitaria sanguinalis) revealed by cDNA-AFLP analysis.

    PubMed

    Wang, Jianshu; Wang, Xuemin; Yuan, Bohua; Qiang, Sheng

    2013-01-01

    Gene expression profiles of Digitaria sanguinalis infected by Curvularia eragrostidis strain QZ-2000 at two concentrations of conidia and two dew durations were analyzed by cDNA amplified fragment length polymorphisms (cDNA-AFLP). Inoculum strength was more determinant of gene expression than dew duration. A total of 256 primer combinations were used for selective amplification and 1214 transcript-derived fragments (TDFs) were selected for their differential expression. Of these, 518 up-regulated differentially expressed TDFs were identified. Forty-six differential cDNA fragments were chosen to be cloned and 35 of them were successfully cloned and sequenced, of which 25 were homologous to genes of known function according to the GenBank database. Only 6 genes were up-regulated in Curvularia eragrostidis-inoculated D. sanguinalis, with functions involved in signal transduction, energy metabolism, cell growth and development, stress responses, abscisic acid biosynthesis and response. It appears that a few pathways may be important parts of the pathogenic strategy of C. eragrostidis strain QZ-2000 on D. sanguinalis. Our study provides the fundamentals to further study the pathogenic mechanism, screen for optimal C. eragrostidis strains as potential mycoherbicide and apply this product to control D. sanguinalis.

  11. Agropyrenol, a phytotoxic fungal metabolite, and its derivatives: a structure-activity relationship study.

    PubMed

    Cimmino, Alessio; Zonno, Maria Chiara; Andolfi, Anna; Troise, Ciro; Motta, Andrea; Vurro, Maurizio; Evidente, Antonio

    2013-02-27

    Agropyrenol is a phytotoxic substituted salicylic aldehyde produced in liquid culture by Ascochyta agropyrina var. nana , a potential mycoherbicide proposed for the control of the perennial weed Elytrigia repens. In this study, six derivatives obtained by chemical modifications of the toxin were assayed for phytotoxic, antimicrobial, and zootoxic activities, and the structure-activity relationships were examined. Each compound was tested on non-host weedy and agrarian plants, fungi, Gram-positive and Gram-negative bacteria, and brine shrimp larvae. The results provide insights into the structure-activity relationships of agropyrenol. Both the double bond and the diol system of the 3,4-dihydroxypentenyl side chain as well as the aldehyde group at C-1 of the phenolic ring of agropyrenol proved to be important for the phytotoxicity. The lesser polar 3',4'-O,O'-isopropylidene of agropyrenol also showed significant zootoxic and slight antimicrobial activities. This finding could be useful in devising new natural herbicides for practical application in agriculture.

  12. Bio-control potential of Cladosporium sp. (MCPL-461), against a noxious weed Parthenium hysterophorus L.

    PubMed

    Kumar, Anuj; Verma, V C; Gond, S K; Kumar, V; Kharwar, R N

    2009-03-01

    The phenological survey of Parthenium hysterophorus L., in and around the campus of Banaras Hindu University (BHU) was done for about two years (2004-06). During Nov 2004, a few Parthenium plants were found diseased, and symptoms were restricted to the flowers, buds, and inflorescences. The disease causes sterility and reduces seed viability, which was observed with seed germination test from infected and healthy plants. The fungal pathogen was isolated and identified as Cladosporium sp. (MCPL-461). The severity of pathogen to the reproductive organs led to serious damages of the Parthenium plants. Thus in vitro and in vivo experiments were conducted to determine the bio-control potential of Cladosporium sp. (MCPL 461) against Parthenium weed. A combinatorial effort of Cladosporium sp. (MCPL 461) bio-control potential was evaluated with different culture media, incubation periods and spores strength. Spore suspension of 10(5) to 10(12) spores ml(-1) were used to spray on healthy Parthenium plants, and it was found that severe infection symptoms were appeared at 10(10) to 10(12) spores ml(-1) suspension. LD50 was found at 10(7) spores ml(-1). To enhance the myco-herbicide activity 3% sucrose was added to the spore suspension, which further resolute the bio-control efficacy of the isolates. Only 20-30% seeds of infected plants could germinate. However the safety of non-targeted and wild plants was also tested with Lantana camera, Chromolaena odorata and found that suspension up to 10(12) spores ml(-1) were not sufficient for disease outbreak in them.