Project description:Nuts of the sweet chestnut (Castanea sativa) are a widely appreciated traditional food in Europe. In recent years producers and consumers reported a drop of nut quality due to the presence of rot diseases caused by Gnomoniopsis smithogilvyi. Early detection of this pathogen is fundamental to the economic viability of the chestnut industry. In the present study, we developed three molecular methods based on real-time portable LAMP, visual LAMP and qPCR assays for G. smithogilvyi. The molecular assays were specific for G. smithogilvyi and did not amplify the other 11 Gnomoniopsis species and 11 other fungal species commonly associated with chestnuts. The detection limit of both the qPCR and real-time portable LAMP (P-LAMP) assays was 0.128 pg/µL, while the visual LAMP (V-LAMP) assay enabled the detection up to 0.64 pg/µL. By using these newly developed molecular tools, the pathogen was detected in symptomatic and asymptomatic nuts, but not in leaves. The reliability of these molecular methods, including the P-LAMP assay, was particularly useful in detecting G. smithogilvyi of harvested nuts in field, even in the absence of rot symptoms.
Project description:The first genome assemblies of Gnomoniopsis castaneae (syn. G. smithogilvyi), the causal agent of chestnut brown rot of kernels, shoot blight and cankers, are provided here. Specifically, the complete genome of the Italian ex-type MUT401 isolate was compared to the draft genome of a second Italian isolate (GN01) and to the ICMP 14040 isolate from New Zealand. The three genome sequences were obtained through a hybrid assembly using both short Illumina reads and long Nanopore reads, their coding sequences were annotated and compared with each other and with other Diaporthales. The information offered by the genome assembly of the three isolates represents the base of data for further application related to -omics strategies of the fungus and to develop markers for population studies at a local and global scale.
