Genome sequencing of Rigidoporus microporus provides insights on genes important for wood decay, latex tolerance and interspecific fungal interactions

Abstract

fungal plant pathogens remain a serious threat to the sustainable agriculture and forestry, despite the extensive efforts undertaken to control their spread. White root rot disease is threatening rubber tree (Hevea brasiliensis) plantations throughout South and Southeast Asia and Western Africa, causing tree mortality and severe yield losses. Here, we report the complete genome sequence of the basidiomycete fungus Rigidoporus microporus, a causative agent of the disease. Our phylogenetic analysis confirmed the position of R. microporus among the members of Hymenochaetales, an understudied group of basidiomycetes. Our analysis further identified pathogen's genes with a predicted role in the decay of plant cell wall polymers, in the utilization of latex components and in interspecific interactions between the pathogen and other fungi. We also detected putative horizontal gene transfer events in the genome of R. microporus. The reported first genome sequence of a tropical rubber tree pathogen R. microporus should contribute to the better understanding of how the fungus is able to facilitate wood decay and nutrient cycling as well as tolerate latex and utilize resinous extractives.The white rot fungus known as Rigidoporus microporus (Sw.) Overeem (Basidiomycota, Agaricomycotina) is the most economically important pathogen of the tropical tree Hevea brasiliensis (Willd. ex A. Juss.) Müll.Arg., also known as Para rubber. Para rubber is principally valued for its latex content; the latex or natural rubber is a very significant industrial commodity used in a variety of industries from car manufacturing to healthcare. The market value of global annual production of natural rubber is over US$ 50 billion. Elastomers derived from natural rubber are indispensable in space, water, and ship technologies 1 . A major part of the plantation forestry in Africa and Asia is the growing of Para rubber.Rigidoporus microporus is therefore a fungal species of significant economic importance. As a necrotrophic pathogen, it has an extensive host range and affects many tropical and subtropical trees, food and cash crops 2,3 . However, it is best known as a causative agent of the white root rot disease of the rubber tree and for the devastating impact it has on commercial rubber tree plantations ( Fig. 1) 4 . The fungus produces rhizomorphs (thread-like mycelial aggregation of fungal hypha), which can grow several meters in the soil before they reach and attack roots of a suitable host, and it continues to rot wood long after the tree has fallen 5 . Population genetic studies suggested that a host jump and the lack of coevolution between the host and the pathogen might be the possible reasons for the aggressive behavior of the pathogen on rubber trees. This is further supported by the fact that the disease is devastating in Asia and West Africa, but not a serious problem in South America, the centre of origin of the rubber tree host 3 . Presence of high density of fungal rhizomorphs of R. microporus in the soil indicates a capacity to switch...

Distribution of methionine sulfoxide reductases in fungi and conservation of the free-methionine-R-sulfoxide reductase in multicellular eukaryotes

“…Rickenella fibula HBK330-10 v1.0 [280]; Rickenella mellea v1.0 (SZMC22713; [281]; Rigidoporus microporus ED310 v1.0 [282]; Rozella allomycis CSF55 [283]; Saccharomyces arboricola H-6 […”

Genomic and Experimental Investigations of Auriscalpium and Strobilurus Fungi Reveal New Insights into Pinecone Decomposition

“…Latex is a complex emulsion that includes a diversity of chemicals such as proteins, alkaloids, carbohydrates, oils, tannins, and resins that coagulate on exposure to air (Konno, 2011). It is commonly produced by plants after tissue injury and serve as a defense against pathogens and pests (Oghenekaro et al, 2020). Here we used the high expressed genes induced by latex treatment in R .microporus to infer the distributions of these genes in the seven fungi analyzed in our study.…”

“…Peptidases S8 and S53 are among the top 10 most up-regulated enzymes inR . microporus in the presence of latex (Oghenekaro et al, 2020) (Table 2). The genomic evidence is consistent withAuriscalpium fungi capable of colonizing newly fallen cones and decomposing proteins in resin rapidly.…”

Non-Timber Forest Products in Brazil: A Bibliometric and a State of the Art Review

“…The rubber tree (Hevea brasiliensis L.) is widely cultivated in the Amazon region and is managed for the extraction of latex. The most valued product is rubber, used from the automotive industry to chemical and pharmaceutical, for this reason, a large part of forest plantations in Africa and Asia are also used to produce this crop [36].…”