Selective feeding behaviors illuminate patterns of sap beetle associations with ophiostomatoid fungi

Sap beetles (Coleoptera: Nitidulidae) are commonly associated with ophiostomatoid fungi, especially those belonging to the family Ceratocystidaceae. This coexistence of insects and fungi, usually on tree wounds, offers the ophiostomatoid fungi an effective means of dispersal. The selective advantage of this association to sap beetles is, however, confounded by the versatile life history strategies of these insects. In this study, we complemented field observations with rearing and feeding behavior experiments in the laboratory, to investigate the symbiology of interactions between sap beetles and co-occurring fungi, from the insect perspective. We determined that all predominant sap beetle vectors of the Ceratocystidaceae in a natural woodland feed on and use the mycelial mats of these fungi to nurse their offspring in tree wounds. When reared on fungal cultures in the laboratory, several of these insects successfully completed their life cycle. We were able to maintain Carpophilus hemipterus on this exclusive fungal diet over several generations. The feeding preference of this insect was generally consistent with the patterns of its fungal associations in the field as previously reported. There also appeared to be a correlation between the attractiveness of Ca. hemipterus to various fungi and its fitness benefits from feeding on these fungi. Overall, our results suggest that, from their partnership with ophiostomatoid fungi, sap beetles benefit from essential nutritional supplementation, enabling them to survive in saproxyly in woodland ecosystems.The DST/NRF Center of Excellence in Tree Health Biotechnology (CTHB) of South Africa.http://link.springer.com/journal/13199hj2021Forestry and Agricultural Biotechnology Institute (FABI)Plant Production and Soil Scienc

Molecular phylogenetic analyses reveal three new Ceratocystis species and provide evidence for geographic differentiation of the genus in Africa

The emergence of wattle wilt disease on non-native Acacia mearnsii trees in Africa, caused by the indigenous fungus Ceratocystis albifundus, has highlighted a need to better understand the diversity, ecology and distribution of Ceratocystis species in natural African environments. In this study we applied phylogenetic inference to identify and characterize isolates of Ceratocystis collected in a natural savanna ecosystem in South Africa. Three new species were recognized and are described as C. cryptoformis sp. nov. in the C. moniliformis complex, as well as C. thulamelensis sp. nov. and C. zambeziensis sp. nov., both residing in the C. fimbriata complex. Incorporating the new species into global phylogenies of Ceratocystis provided insights into the patterns of evolution and biogeography of this group of fungi. Notably, the African continent was identified as an important centre of diversification of Ceratocystis spp., from which several lineages of these fungi were shown to have radiated.http://link.springer.com/journal/11557hb201

New Ceratocystis species from Eucalyptus and Cunninghamia in South China

During routine surveys for possible fungal pathogens in the rapidly expanding plantations of Eucalyptus and Cunninghamia lanceolata in China, numerous isolates of unknown species in the genus Ceratocystis (Microascales) were obtained from tree wounds. In this study we identified the Ceratocystis isolates from Eucalyptus and Cunninghamia in the GuangDong, GuangXi, FuJian and HaiNan Provinces of South China based on morphology and through comparisons of DNA sequence data for the ITS, partial β-tubulin and TEF-1α gene regions. Morphological and DNA sequence comparisons revealed two previously unknown species residing in the Indo-Pacific Clade. These are described here as C. cercfabiensis sp. nov. and C. collisensis sp. nov. Isolates of C. cercfabiensis showed intragenomic variation in their ITS sequences and four strains were selected for cloning of the ITS gene region. Twelve ITS haplotypes were obtained from 17 clones selected for sequencing,differing in up to seven base positions and representing two separate phylogenetic groups. This is the first evidence of multiple ITS types in isolates of Ceratocystis residing in the Indo-Pacific Clade. Caution should thus be exercised when using the ITS gene region as a barcoding marker for Ceratocystis species in this clade. This study also represents the first record of a species of Ceratocystis from Cunninghamia.This study was initiated through the bilateral agreement between the Governments South Africa and China, and we are grateful for the funding via projects 2012DFG31830 (International Science & Technology Cooperation Program of China), 31400546 (National Natural Science Foundation of China: NSFC),2010KJCX015-03 (Forestry Science and Technology Innovation Project of Guangdong Province of China). The Tree Protection and Cooperation Programme (TPCP) and the National ResearchFoundation (NRF), South Africa.http://link.springer.com/journal/104822016-06-30hb201

Novel species of Huntiella from naturally-occurring forest trees in Greece and South Africa

Huntiella species are wood-infecting, filamentous ascomycetes that occur in fresh wounds on a wide variety of tree species. These fungi are mainly known as saprobes although some have been associated with disease symptoms. Six fungal isolates with typical culture characteristics of Huntiella spp. were collected from wounds on native forest trees in Greece and South Africa. The aim of this study was to identify these isolates, using morphological characters and multigene phylogenies of the rRNA internal transcribed spacer (ITS) region, portions of the β-tubulin (BT1) and translation elongation factor 1α (TEF-1α) genes. The mating strategies of these fungi were also determined through PCR amplification of mating type genes. The study revealed two new species; one from Platanus orientalis in Greece and one from Colophospermum mopane and Senegalia nigrescens in South Africa. These novel taxa have been provided with the names, H. hellenica sp. nov. and H. krugeri sp. nov., respectively. The former species was found to have a homothallic and the latter a heterothallic mating system.Supplementary material 1 : Figure S1. ML tree of Huntiella species generated from the ITS DNA sequence data Authors: FeiFei Liu, Seonju Marincowitz, ShuaiFei Chen, Michael Mbenoun, Panaghiotis Tsopelas, Nikoleta Soulioti, Michael J. Wingfield Data type: phylogenetic tree Explanation note: Sequences generated from this study are printed in bold type. Bold branches indicate posterior probabilities values ≥ 0.9. Bootstrap values and posterior probabilities value are presented above branches as ML/MP/BI. Bootstrap value < 50% or probabilities values < 0.9 are marked with *. Nodes lacking the support value are marked with -. Ceratocystis cercfabiensis (CMW 43029) represents the outgroup. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/mycokeys.69.53205.suppl1Supplementary material 2 : Figure S2. ML tree of Huntiella species generated from the BT1 DNA sequence data Authors: FeiFei Liu, Seonju Marincowitz, ShuaiFei Chen, Michael Mbenoun, Panaghiotis Tsopelas, Nikoleta Soulioti, Michael J. Wingfield Data type: phylogenetic tree Explanation note: Sequences generated from this study are printed in bold type. Bold branches indicate posterior probabilities values ≥ 0.9. Bootstrap values and posterior probabilities values are presented above branches as ML/MP/BI. Bootstrap value < 50% or probabilities values < 0.9 are marked with *. Nodes lacking the support value are marked with -. Ceratocystis cercfabiensis (CMW 43029) represents the outgroup. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/mycokeys.69.53205.suppl2 52 FeiFei Liu et al. / MycoKeys 69: 33–52 (2020)Supplementary material 3 : Figure S3. ML tree of Huntiella species generated from the TEF-1α DNA sequence data Authors: FeiFei Liu, Seonju Marincowitz, ShuaiFei Chen, Michael Mbenoun, Panaghiotis Tsopelas, Nikoleta Soulioti, Michael J. Wingfield Data type: phylogenetic tree Explanation note: Sequences generated from this study are printed in bold type. Bold branches indicate posterior probabilities values ≥ 0.9. Bootstrap values and posterior probabilities values are presented above branches as ML/MP/BI. Bootstrap value < 50% or probabilities values < 0.9 are marked with *. Nodes lacking the support value are marked with -. Ceratocystis cercfabiensis (CMW 43029) represents the outgroup. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/mycokeys.69.53205.suppl3Members of Tree Protection and Cooperation Programme (TPCP) and the National Research Foundation (NRF), South Africa.https://mycokeys.pensoft.netam2021BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Diversity and pathogenicity of the Ceratocystidaceae associated with cacao agroforests in Cameroon

Knowledge of the diversity and ecology of plant pathogenic fungi in cacao agroforests and surrounding natural ecosystems can inform the development of sustainable management strategies for new cacao disease outbreaks. In this study, we investigated the occurrence of fungi related to the Ceratocystisdaceae and their nitidulid beetle vectors in cacao agroforests in Cameroon, under diverse agroecological conditions. The fungi and their vectors were collected from artificially induced stem wounds on cacao and associated shade trees. Collections were also made from abandoned cacao pod husks and other tree wounds within and around plantations. Fungal isolates were identified using DNA sequence-based phylogenies and morphological comparisons, and two representatives of each species were evaluated for pathogenicity on cacao. Five species of Ceratocystidaceae were recovered, including Huntiella chlamydoformis sp. nov., H. pycnanthi sp. nov. and H. moniliformis, as well as Thielaviopsis cerberus and Th. ethacetica. The incidence of these fungi appeared to be influenced by the prevailing agroecological conditions. Nitidulid beetles in the genus Brachypeplus were found to be their most common insect associates on cacao. Both Th. ethacetica and H. pycnanthi produced extensive lesions after inoculation on branches of mature cacao trees, while Th. ethacetica also caused pod rot. Although their impact remains unknown, fungi in the Ceratocystidaceae and their nitidulid beetle vectors are common and likely contribute to the parasitic pressure in Cameroonian cacao agrosystems.NRF-DST Centre of Excellence in Tree Health Biotechnology (CTHB) of South Africa and the Department of Corporate International Relations of the University of Pretoria through a postgraduate ‘study abroad grant’.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-30592017-01-31hb2016Forestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Armillaria root rot threatens Cameroon’s Penja pepper (Piper nigrum L.)

Penja pepper (Piper nigrum) produced in Cameroon has long been recognized for its exceptional organoleptic quality. The pepper vine is grown using a support tree (Spondias mombin) in Cameroon. A root disease is associated with plant deaths in both plants. The disease symptoms are characterized by collar cracking and gummosis and the disease was tentatively identified as Armillaria root rot. In this work the extent of the problem was characterized by surveying 35 farms in Cameroon. Samples were taken from diseased support trees and pepper vines. Support trees exhibiting typical symptoms were found in approximately one third of the surveyed farms. In these farms, disease incidence and Pepper vine mortality ranged from 1.3 to 50% and 1.2 to 87.7%, respectively. Analysis of the ribosomal internal transcribed spacer region (ITS) locus suggested that the isolates collected from S. mombin and P. nigrum are most likely, which is a first for both hosts, represented by Armillaria camerunensis (Henn.) Volk & Burdsall, a fungus previously associated with declining cacao trees in Cameroon. Given the increasing demand for Penja pepper and the great damaging potential of this root rot, research on management strategies should be prioritized.CIRAD, IRAD, the University of Pretoria and through the “Debt reduction-development contract (C2D) France Cameroon” Poivre de Penja project.https://link.springer.com/journal/40858am2021BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologyPlant Production and Soil Scienc