Project description:BackgroundApple production in Sweden and elsewhere is being threatened by the fungus, Neonectria ditissima, which causes a disease known as European canker. The disease can cause extensive damage and the removal of diseased wood and heavily infected trees can be laborious and expensive. Currently, there is no way to eradicate the fungus from infected trees and our knowledge of the infection process is limited. Thus, to target and modify genes efficiently, the genetic transformation technique developed for N. ditissima back in 2003 was modified.ResultsThe original protocol from 2003 was upgraded to use enzymes currently available in the market for making protoplasts. The protoplasts were viable, able to uptake foreign DNA, and able to regenerate back into a mycelial colony, either as targeted gene-disruption mutants or as ectopic mutants expressing the green fluorescent protein (GFP).ConclusionsA new genetic transformation protocol has been established and the inclusion of hydroxyurea in the buffer during the protoplast-generation step greatly increased the creation of knockout mutants via homologous recombination. Pathogenicity assays using the GFP-mutants showed that the mutants were able to infect the host and cause disease.

| S-EPMC9373326 | biostudies-literature

The interplay between scion genotype, root microbiome, and Neonectria ditissima apple canker.

Project description:Severity of European apple canker caused by Neonectria ditissima can vary between locations and apple genotypes. We investigated how location, cold storage/planting season, and apple scion genotype affect root-associated microbial communities. Additionally, we investigated whether differences in abundance of specific taxa could be associated with canker lesion counts. Seven scion cultivars grafted onto M9 rootstocks were inoculated with N. ditissima in the nursery and then planted in December 2018 or stored at 2°C until planting in April 2019 at three sites in Kent, UK. We assessed canker lesions and collected root samples in June 2021. Quantitative polymerase chain reaction (qPCR) and internal transcribed spacer (ITS)/16S rRNA gene amplicon sequencing was used to analyse microbial communities. Site was the primary factor affecting microbiome size, diversity, and composition. Cold storage/planting season had small but significant effects, indicating that differences in the microbiome at planting can persist long-term. Scion genotype had a limited effect on diversity but did influence the abundance of specific root-associated taxa. Bacterial α-diversity was associated with canker count in a site-dependent manner. Increased abundances of particular fungal (Rhizophagus irregularis and Epicoccum nigrum) and bacterial (Amycolatopsis and Bradyrhizobium) root-associated taxa were associated with fewer cankers.

| S-EPMC11878798 | biostudies-literature

Draft Genome Sequence of a European Isolate of the Apple Canker Pathogen Neonectria ditissima.

Project description:The Sordariomycetes fungus Neonectria ditissima is a major pathogen of apples, causing canker on trees and fruit spoilage. We report here the draft genome sequence of a European strain isolated from cankerous tissue.

| S-EPMC4653771 | biostudies-literature

Fungal and bacterial endophytes in apple trees

Project description:This study shows that the diversity of fungal and bacterial endophytes in apple trees is influenced by site and tree genotype and associated with susceptibility to Neonectria ditissima

| PRJEB44670 | ENA

Neonectria

Project description:Neonectria sp. overview

| PRJNA1202250 | ENA

Neonectria lugdunensis

Project description:Neonectria lugdunensis overview

| PRJNA1149140 | ENA