Anthracnose disease of switchgrass caused by the novel fungal species Colletotrichum navitas

ABSTRACTThe global regulatoryveAgene governs development and secondary metabolism in numerous fungal species, includingAspergillus flavus. This is especially relevant sinceA. flavusinfects crops of agricultural importance worldwide, contaminating them with potent mycotoxins. The most well-known are aflatoxins, which are cytotoxic and carcinogenic polyketide compounds. The production of aflatoxins and the expression of genes implicated in the production of these mycotoxins areveAdependent. The genes responsible for the synthesis of aflatoxins are clustered, a signature common for genes involved in fungal secondary metabolism. Studies of theA. flavusgenome revealed many gene clusters possibly connected to the synthesis of secondary metabolites. Many of these metabolites are still unknown, or the association between a known metabolite and a particular gene cluster has not yet been established. In the present transcriptome study, we show thatveAis necessary for the expression of a large number of genes. Twenty-eight out of the predicted 56 secondary metabolite gene clusters include at least one gene that is differentially expressed depending on presence or absence ofveA. One of the clusters under the influence ofveAis cluster 39. The absence ofveAresults in a downregulation of the five genes found within this cluster. Interestingly, our results indicate that the cluster is expressed mainly in sclerotia. Chemical analysis of sclerotial extracts revealed that cluster 39 is responsible for the production of aflavarin.

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Defining pheromone-receptor signaling inCandida albicansand related asexualCandidaspecies

Molecular Biology of the Cell ◽

10.1091/mbc.e11-09-0749 ◽

2011 ◽

Vol 22 (24) ◽

pp. 4918-4930 ◽

Cited By ~ 13

Author(s):

Ching-Hsuan Lin ◽

Anthony Choi ◽

Richard J. Bennett

Keyword(s):

Candida Albicans ◽

Candida Species ◽

Cellular Response ◽

Fungal Species ◽

The Novel ◽

Pheromone Receptor ◽

Human Fungal Pathogen ◽

Α Pheromone ◽

Candida Lusitaniae ◽

Sexual Mating

Candida albicans is an important human fungal pathogen in which sexual reproduction is under the control of the novel white–opaque switch. Opaque cells are the mating-competent form, whereas white cells do not mate but can still respond to pheromones, resulting in biofilm formation. In this study, we first define the domains of the α-pheromone receptor Ste2 that are necessary for signaling in both white and opaque forms. Both cell states require the IC loop 3 (IC3) and the C-terminal tail of Ste2 for the cellular response, whereas the first IC loop (IC1) of Ste2 is dispensable for signaling. To also address pheromone-receptor interactions in related species, including apparently asexual Candida species, Ste2 orthologues were heterologously expressed in Candida albicans. Ste2 receptors from multiple Candida clade species were functional when expressed in C. albicans, whereas the Ste2 receptor of Candida lusitaniae was nonfunctional. Significantly, however, expression of a chimeric C. lusitaniae Ste2 receptor containing the C-terminal tail of Ste2 from C. albicans generated a productive response to C. lusitaniae pheromone. This system has allowed us to characterize pheromones from multiple Candida species and indicates that functional pheromone-receptor couples exist in fungal species that have yet to be shown to undergo sexual mating.

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Persimmon anthracnose: a comparative study of aggressiveness on shoot and fruit among Colletotrichum horii isolates in southern Brazil

Ciência Rural ◽

10.1590/0103-8478cr20200198 ◽

2020 ◽

Vol 50 (10) ◽

Author(s):

Renato Rezende Young Blood ◽

Thiago de Aguiar Carraro ◽

Josiane Gomes Figueiredo ◽

Louise Larissa May De Mio

Keyword(s):

Severe Disease ◽

Its Region ◽

Field Studies ◽

Fungal Species ◽

Metropolitan Region ◽

Disease Symptoms ◽

Immature Fruit ◽

Anthracnose Disease ◽

Persimmon Fruit ◽

Fruit Drop

ABSTRACT: The persimmon tree is known for its rusticity and productivity and was first introduced to Brazil in the late 19th century. However, anthracnose disease is causing immature fruit drop and severe disease symptoms in persimmon fruit, shoots, flowers, and twigs. The causal agent was first described as the fungal species, Colletotrichum horii, which was first confirmed using only the ITS region. In this study, we compared the aggressiveness of 13 isolates of Colletotrichum spp. obtained from fruit and shoots of persimmon grown in the Metropolitan Region of Curitiba, Paraná State, Brazil. A multilocus molecular analysis was carried out based on ITS, GPDH, and EF genes, and we confirmed that the isolates were confirmed as C. horii. All isolates were pathogenic for unwounded and wounded persimmon fruit but differed in aggressiveness. Only one isolate was non-pathogenic when inoculated into unwounded persimmon shoots. Most isolates caused cankers and shoot death whether shoots were wounded or unwounded. In this study, we emphasized the importance of shoots as a source of primary inoculum. In future studies, it will be critical to further elucidate the epidemiological basis of anthracnose disease by conducting field studies to establish a more effective strategy for disease control.

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Host-induced silencing of the Colletotrichum gloeosporioides conidial morphology 1 gene (CgCOM1) confers resistance against Anthracnose disease in chilli and tomato

10.1101/2020.01.03.893677 ◽

2020 ◽

Author(s):

Binod Kumar Mahto ◽

Anjulata Singh ◽

Manish Pareek ◽

Manchikatla V. Rajam ◽

Swatismita Dhar-Ray ◽

...

Keyword(s):

Gene Expression ◽

Pathogenic Fungi ◽

Fungal Species ◽

Wild Type ◽

Rt Pcr ◽

Stem Loop ◽

Anthracnose Disease ◽

Gene Expression Analyses ◽

Transgenic Lines ◽

Appressoria Formation

AbstractAnthracnose disease is caused by the ascomycetes fungal species Colletotrichum, which is responsible for heavy yield losses in chilli and tomato worldwide. Conventionally, harmful pesticides are used to contain anthracnose disease with limited success. In this study, we assessed the potential of Host-Induced Gene Silencing (HIGS) approach to target the Colletotrichum gloeosporioides COM1 (CgCOM1) developmental gene involved in the fungal conidial and appressorium formation, to restrict fungal infection in chilli and tomato fruits. For this study, we have developed stable transgenic lines of chilli and tomato expressing CgCOM1-RNAi construct employing Agrobacterium-mediated transformation. Transgenic plants were characterized by molecular and gene expression analyses. Production of specific CgCOM1 siRNA in transgenic chilli and tomato RNAi lines was confirmed by stem-loop RT-PCR. Fungal challenge assays on leaves and fruits showed that the transgenic lines were resistant to anthracnose disease-causing C. gloeosporioides in comparison to wild type and empty-vector control plants. RT-qPCR analyses in transgenic lines revealed barely any CgCOM1 transcripts in the C. gloeosporioides infected tissues, indicating near complete silencing of CgCOM1 gene expression in the pathogen. Microscopic examination of the Cg-challenged leaves of chilli-CgCOM1i lines revealed highly suppressed conidial germination, germ tube development, appressoria formation and mycelial growth of C. gloeosporioides, resulting in reduced infection of plant tissues. These results demonstrated highly efficient use of HIGS in silencing the expression of essential fungal developmental genes to inhibit the growth of pathogenic fungi, thus providing a highly precise approach to arrest the spread of disease.

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Mucor nidicola sp. nov., a fungal species isolated from an invasive paper wasp nest

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.033050-0 ◽

2012 ◽

Vol 62 (Pt_7) ◽

pp. 1710-1714 ◽

Cited By ~ 7

Author(s):

A. A. Madden ◽

A. M. Stchigel ◽

J. Guarro ◽

D. Sutton ◽

P. T. Starks

Keyword(s):

Type Strain ◽

Novel Species ◽

Fungal Species ◽

Paper Wasp ◽

Rrna Gene ◽

The Novel ◽

Polistes Dominulus ◽

5.8S Rrna Gene ◽

5.8S Rrna ◽

Physiological Tests

A strain of a novel mucoralean fungus was isolated from a nest of the invasive paper wasp, Polistes dominulus. Phylogenetic analysis based on the internal transcribed spacer (ITS) regions and 5.8S rRNA gene sequences, along with physiological tests, revealed that this strain represents a novel species within the genus Mucor. The novel species also includes a representative that had previously been characterized as part of the Mucor hiemalis complex. Unlike the type strain of M. hiemalis, these two strains can grow at 37 °C and sporulate at 35 °C. Here, we present a partial resolution of the M. hiemalis species complex and propose the novel species Mucor nidicola sp. nov. to accommodate the isolate; the type strain of M. nidicola is F53T ( = NRRL 54520T = UAMH 11442T = CBS 130359T).

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Ophiobolus hydei sp. nov. (Phaeosphaeriaceae, Ascomycota) from Cirsium and Phlomoides in Uzbekistan

Botany ◽

10.1139/cjb-2019-0118 ◽

2019 ◽

Vol 97 (12) ◽

pp. 671-680 ◽

Cited By ~ 1

Author(s):

Yusufjon Gafforov ◽

Rungtiwa Phookamsak ◽

Hong-Bo Jiang ◽

Dhanushka N. Wanasinghe ◽

Mukhiddin Juliev

Keyword(s):

New Species ◽

Novel Species ◽

Phylogenetic Analyses ◽

Fungal Species ◽

Tien Shan ◽

Gene Analysis ◽

The Novel ◽

Distribution Map ◽

Close Affinity

We introduce a new fungal species, Ophiobolus hydei, from dead stems of Cirsium alatum (Compositae) and Phlomoides brachystegia (Lamiaceae), based on morphological and phylogenetic evidence. The species was collected from the Mountains of Western Tien Shan and southwestern Hissar in Uzbekistan. Ophiobolus hydei is characterized by globose to subglobose ascomata with short to long papilla, cylindrical to subcylindric-clavate asci, broad pseudoparaphyses, and scolecosporous, yellowish-brown to brown, filiform, multiseptate ascospores that can split into several part-spores at the septa. Multigene phylogenetic analyses using a combined gene analysis of ITS, LSU, SSU, and TEF1-α indicated that the new species has a close affinity to Ophiobolus ponticus, but differs from that species in the micromorphological characteristics of the ascomata, asci, and ascospores, as well as biogeographic distribution. A distribution map, morphological descriptions, and illustrations with colour photographs of the novel species are provided.

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Anthracnose disease of centipedegrass turf caused by Colletotrichum eremochloae, a new fungal species closely related to Colletotrichum sublineola

Mycologia ◽

10.3852/11-317 ◽

2012 ◽

Vol 104 (5) ◽

pp. 1085-1096 ◽

Cited By ~ 19

Author(s):

J. A. Crouch ◽

M. Tomaso-Peterson

Keyword(s):

Fungal Species ◽

Anthracnose Disease

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Aspergillus Goes Viral: Ecological Insights from the Geographical Distribution of the Mycovirome within an Aspergillus flavus Population and Its Possible Correlation with Aflatoxin Biosynthesis

Journal of Fungi ◽

10.3390/jof7100833 ◽

2021 ◽

Vol 7 (10) ◽

pp. 833

Author(s):

Francesca Degola ◽

Giorgio Spadola ◽

Marco Forgia ◽

Massimo Turina ◽

Lucia Dramis ◽

...

Keyword(s):

Aspergillus Flavus ◽

Aflatoxin Production ◽

Fungal Species ◽

Natural Environments ◽

The Novel ◽

Aflatoxin Biosynthesis ◽

Biological Variables ◽

Pattern Distribution ◽

Toxigenic Strains

Microbial multi-level interactions are essential to control the success of spreading and survival of most microbes in natural environments. Phytopathogenic mycotoxigenic fungal species, such as Aspergillus flavus, represent an important issue in food safety. Usually, non-toxigenic strains are exploited for biocontrol strategies to mitigate infections by toxigenic strains. To comprehend all the biological variables involved in the aflatoxin biosynthesis, and to possibly evaluate the interplay between A. flavus toxigenic and non-toxigenic strains during intraspecific biocompetition, the “virological” perspective should be considered. For these reasons, investigations on mycoviruses associated to A. flavus populations inhabiting specific agroecosystems are highly desirable. Here, we provide the first accurate characterization of the novel mycovirome identified within an A. flavus wild population colonizing the maize fields of northern Italy: a selection of A. flavus strains was biologically characterized and subjected to RNAseq analysis, revealing new mycoviruses and a peculiar geographic pattern distribution in addition to a 20% rate of infection. More interestingly, a negative correlation between viral infection and aflatoxin production was found. Results significantly expanded the limited existent data about mycoviruses in wild A. flavus, opening new and intriguing hypotheses about the ecological significance of mycoviruses.

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