The jackfruit tree (Artocarpus heterophyllus) is a tropical species of significant importance, widely distributed in various geographical regions of Brazil, where its fruits, known as jackfruit, are ...consumed fresh. Between 2019 and 2023, in three distinct geographical regions of Brazil, a 100% incidence of black rot was observed in jackfruit fruits. Additionally, symptoms of dieback were identified in jackfruit trees in these regions. Faced with this issue, the present study aims to identify the etiological agents associated with these two symptoms, employing morphological characterization, nucleotide sequencing, and inoculations in fruits and seedlings. Through sequencing of the ITS, TEF, and TUB2 regions, the isolates were grouped with references of Lasiodiplodia theobromae and L. brasiliense. The inoculated fungi were reisolated, maintaining the same morphological characteristics. This study constitutes the first report of L. theobromae and L. brasiliense as causative agents of fruit rot and dieback in jackfruit in Brazil.
•Black rot and dieback disease of jackfruit tree were very popular in three distinct geographical regions of Brazil.•Lasiodiplodia theobromae and L. brasiliense were isolated, identified by morphological and molecular methods, and finished Koch's postulates.•The first report of L. theobromae and L. brasiliense as causative agents of fruit rot and dieback in jackfruit in Brazil.
During the last five years a decline of table grape plants has been noticed in nurseries, young plantations and vineyards of the Northeastern region of Brazil, where the management systems for ...grapevine production are adapted to the specific environmental conditions of a tropical viticulture. Samples of table grape plants showing decline symptoms were obtained from grapevine nurseries, young plantations and vineyards located in the São Francisco, Assú and Siriji Valleys in 2010, and were subjected to fungal isolation. Grapevine trunk pathogens were identified using morphological and molecular methods. Species recovered included Botryosphaeria mamane, Campylocarpon fasciculare, C. pseudofasciculare, Lasiodiplodia crassipora, L. parva, L. pseudotheobromae, L. theobromae, Neofusicoccum parvum, Phaeoacremonium aleophilum, Pm. parasiticum and Phaeomoniella chlamydospora. They are all reported for the first time on grapevine in Brazil, with the exception of L. theobromae. Moreover, Botryosphaeria mamane, Lasiodiplodia parva and L. pseudotheobromae are reported for the first time on grapevine, and C. fasciculare is reported for the first time on the American continent.
Bananas are the most widely produced fruit in the world. Crown rot, one of the main postharvest diseases of banana fruit, causes significant losses during storage, transportation, and marketing. ...Different fungi, especially species of the genus Lasiodiplodia, are associated with this disease. Lasiodiplodia isolates were obtained from asymptomatic fruits in the states of Alagoas, Ceará and Pernambuco, Brazil. On Potato Dextrose Agar (PDA), the isolates initially produced moderately dense grayish-white mycelium, then turned olive green to grayish-black, with olive-green or black reverses. The fungal isolate was classified as Lasiodiplodia hormozganensis and Lasiodiplodia laeliocattleyae based on morphological and multigene (TEF1-α, ITS and TUB2) phylogenetic analysis. Pathogenicity tests were performed by inoculating mycelial discs containing pathogen structures on banana fruits, confirming Koch's postulates. This is the first report of L. hormozganensis and L. laeliocattleyae causing crown rot disease in banana plants in the world.
•2023, crown rot disease of banana fruit occurring in three geographical areas in the northeast of Brazil.•Lasiodiplodia laelliocatleyae and L. hormozganensis were isolated, identified by morphological and molecular methods, and finished Koch's postulates.•The first report of L. laelliocatleyae and L. hormozganensis as causative agents of crown rot disease on banana fruits in the world.
An apoplectic breakdown from grapevine trunk diseases (GTDs) has become a serious challenge to viticulture as a consequence of drought stress. We hypothesize that fungal aggressiveness is controlled ...by a chemical communication between the host and colonizing fungus. We introduce the new concept of a ‘plant surrender signal’ accumulating in host plants under stress and facilitating the aggressive behaviour of the strain Neofusicoccum parvum (Bt‐67) causing Botryosphaeriaceae‐related dieback in grapevines. Using a cell‐based experimental system (Vitis cells) and bioactivity‐guided fractionation, we identify trans‐ferulic acid, a monolignol precursor, as a ‘surrender signal’. We show that this signal specifically activates the secretion of the fungal phytotoxin fusicoccin A aglycone. We show further that this phytotoxin, mediated by 14‐3‐3 proteins, activates programmed cell death in Vitis cells. We arrive at a model showing a chemical communication facilitating fusicoccin A secretion that drives necrotrophic behaviour during Botryosphaeriaceae–Vitis interaction through trans‐ferulic acid. We thus hypothesize that channelling the phenylpropanoid pathway from this lignin precursor to the trans‐resveratrol phytoalexin could be a target for future therapy.
Summary statement
This study identified for the first time a new level of plant–pathogen crosstalk, the so‐called ‘plant surrender signal’, which triggers the endophyte transition from asymptomatic commensalism to a necrotrophic lifestyle killing the vine ‘Vitis vinifera’ in a few days
In July 2019, samples of plagiotropic and orthotropic branches of C. canephora with symptoms of dieback were collected in Santa Tereza, Espírito Santo state, Brazil, a major coffee growing region in ...the country. At the time, the cause of the symptoms was unknown. This study aimed to determine the cause of the observed symptoms based on multilocus phylogeny, morphology, and colony characterization. The causal agent was identified as Lasiodiplodia iranensis. This pathogen has been reported to cause disease in several economically important crops in South America, including cashew and mango. To the best of our knowledge, this is the first report of L. iranensis causing dieback on C. canephora worldwide.
•Dieback symptoms were observed on Coffea canephora plants in Brazil.•Lasiodiplodia iranensis was identified by morphological and phylogenetic analyses.•L. iranensis was confirmed to be the causal agent of dieback on C. canephora.•This is the first report of L. iranensis causing dieback on C. canephora worldwide.
During June 2018, several symptomatic fig (Ficus carica) cuttings, showing twig blight, subcortical discolouration and apical dieback were collected from a nursery in Catania province, Sicily ...(Italy). Isolations from diseased tissue consistently showed the presence of the same fungal colony. Morphology of the fungal isolates together with sequence data of the nuclear rDNA internal transcriber spacer (ITS) region, translation elongation factor 1-alpha (tef1) gene and partial beta-tubulin (tub2) gene of representatives isolates revealed the presence of the fungus Neofusicoccum parvum. Pathogenicity tests were conducted by inoculating fig cuttings with mycelial plugs. After 10 days, the inoculated plants developed cankers similar to those observed in the greenhouse and after 26 days all inoculated plants were dead. To the best of our knowledge, this is the first report worldwide of N. parvum causing disease on this host.
Fungal diseases are a serious threat to Eucalyptus spp., which are cultivated worldwide for pulp and paper. Robust and timely detection of Eucalyptus pathogens is thus a crucial step in disease ...prevention and control. In 2022, leaf spots were observed on Eucalyptus trees in Karnal, northern India. Fungal isolates displaying morphological characteristics similar to Neofusicoccum mangiferae were consistently recovered from the infected leaves. The morphological identification was validated by phylogenetic analysis employing internal transcribed spacer (ITS), partial translation elongation factor-1α (tef1) and partial β-tubulin (tub2) regions. Finally, Koch's postulates for N. mangiferae as a foliar pathogen of Eucalyptus were fulfilled. This is the first confirmed report of N. mangiferae affecting Eucalyptus trees in India.
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•This study first time reports Neofusicoccum mangiferae as a foliar pathogen of Eucalyptus in India.•The pathogen was identified based on microscopic features, multilocus phylogenetic analysis and pathogenicity tests.•This is a new taxonomic addition to the diversity of Botryosphaeriaceae affecting Eucalyptus in India.•This study provides future directions to decipher the diversity of Neofusicoccum spp., their host range and testing of Eucalyptus germplasm for disease-resistance.
Neofusicoccum is a genus of plant pathogenic fungi associated with various woody plants. Since Neofusicoccum has very similar morphological characteristics to the genus Botryospaheria, molecular ...phylogenetic analysis is essential to determine its taxonomic position. In Japan, a comprehensive taxonomic study of the genus Neofusicoccum has not been conducted. To elucidate the species diversity in Japan, we reexamined Japanese isolates of Neofusicoccum based on their morphology and molecular phylogenetic relationships, using the internal transcribed spacer (ITS) regions rpb2, tef1-α, and tub2. The Japanese isolates were divided into five clades recognized as the species. These species were N. parvum, other Neofusicoccum spp., and three new species proposed in this study, N. hyperici, N. miyakoense, and N. okinawaense. Furthermore, Physalospora laricina, which causes shoot blight of larch (Larix spp.), was transferred to the genus Neofusicoccum, and we propose its epitype and ex-epitype isolate.
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