Beyond the genomes of Fulvia fulva (syn. Cladosporium fulvum) and Dothistroma septosporum: New insights into how these fungal pathogens interact with their host plants

Abstract

Fulvia fulva and Dothistroma septosporum are closely related apoplastic pathogens with similar lifestyles but different hosts: F. fulva is a pathogen of tomato, whilst D. septosporum is a pathogen of pine trees. In 2012, the first genome sequences of these pathogens were published, with F. fulva and D. septosporum having highly fragmented and near‐complete assemblies, respectively. Since then, significant advances have been made in unravelling their genome architectures. For instance, the genome of F. fulva has now been assembled into 14 chromosomes, 13 of which have synteny with the 14 chromosomes of D. septosporum , suggesting these pathogens are even more closely related than originally thought. Considerable advances have also been made in the identification and functional characterization of virulence factors (e.g., effector proteins and secondary metabolites) from these pathogens, thereby providing new insights into how they promote host colonization or activate plant defence responses. For example, it has now been established that effector proteins from both F. fulva and D. septosporum interact with cell‐surface immune receptors and co‐receptors to activate the plant immune system. Progress has also been made in understanding how F. fulva and D. septosporum have evolved with their host plants, whilst intensive research into pandemics of Dothistroma needle blight in the Northern Hemisphere has shed light on the origins, migration, and genetic diversity of the global D. septosporum population. In this review, we specifically summarize advances made in our understanding of the F. fulva –tomato and D. septosporum –pine pathosystems over the last 10 years.

Adaptive evolution of sesquiterpene deoxyphomenone in mycoparasitism byHansfordia pulvinataassociated with horizontal gene transfer fromAspergillusspecies

“…Although it is not directly involved in the mycoparasitism of H. pulvinata and is not toxic to plants, it had significant fungistatic activity against plant pathogens—the host C. fulvum and the nonhost P. fuligena of H. pulvinata —which might indicate a potential effect on biotrophic fungal pathogens of tomato plants. H. pulvinata remains an efficient biocontrol agent that can be used as a biofungicide to suppress races and fungicide-tolerant strains of C. fulvum that cause problems in tomato crops world-wide (Iida et al, 2015; Mesarich et al, 2023). Among Aspergillus species commonly used in fermentation, the use of deoxyphomenone to control sporulation should promote high efficiency for industrial fermentation and enzyme production.…”

“…The biotrophic filamentous fungus Cladosporium fulvum (Cooke) (syn. Passalora fulva , Fulvia fulva ), the causal agent of leaf mold of tomato, is an economic problem in most countries that grow tomatoes (Videira et al, 2017; Mesarich et al, 2023). Following spore germination, hyphae enter the leaf through stomata to absorb nutrients from its host in the apoplast.…”

“…Colonization of tomato leaves by C. fulvum is facilitated by numerous effector proteins that are secreted into the apoplast by the fungus (de Wit, 2016). To combat C. fulvum, breeders have introduced Cf resistance genes, which encode receptor-like proteins with extracytoplasmic leucine-rich repeats, into commercial tomato cultivars from wild relatives (de Wit, 2016;Mesarich, 2023). Tomato Cf gene encoded receptor-like proteins recognize corresponding effector proteins of C. fulvum as virulence factors in the apoplastic region and trigger a hypersensitive response that rapidly kills plant cells near the infection site, inhibiting the growth of the biotrophic pathogen and preventing its spread (Stergiopoulos and de Wit, 2009).…”

Analysis of five near-complete genome assemblies of the tomato pathogen Cladosporium fulvum uncovers additional accessory chromosomes and structural variations induced by transposable elements effecting the loss of avirulence genes

“…However, the assembly was highly fragmented because repetitive regions were not properly assembled. Since then, efforts were made to unravel the genome organization of this pathogen [ 48 ], and a new chromosome-scale reference genome for C. fulvum isolate Race 5 was recently obtained [ 17 ]. The new assembly revealed many features of the C. fulvum genome that were hidden by the former highly fragmented assembly, including the presence of 13 core and 1 accessory chromosome, and a “checkerboard” genome architecture composed of gene-dense and TE-poor regions interspersed with gene-sparse and TE-rich regions.…”

Studies on plant immunity: dissection of the Cf-4/SOBIR1-containing complex in Nicotiana benthamiana

“…Cf-4 is an LRR-RLP that confers resistance to strains of the hemibiotrophic fungal pathogen Cladosporium fulvum (syn. Fulvia fulva), expressing the effector protein Avr4 40,67,68 .…”