Apple endophyte community is shaped by tissue type, cultivar and site and has members with biocontrol potential againstNeonectria ditissima

Abstract

Aims This research aimed to identify factors influencing endophyte community structure in apple shoots and the bioactivity of cultured representatives against the fungal pathogen Neonectria ditissima. Methods and Results The endophyte community in leaves and stems of the apple cultivars ‘Royal Gala’ and ‘Braeburn’ were analysed by a cultivation‐independent method (PCR‐DGGE) which showed that tissue type, cultivar and site were determinant factors, with the endophyte taxa in ‘Royal Gala’ more variable than that in ‘Braeburn’, with leaf endophyte communities typically differing from stems in both cultivars. Seasonal (spring vs autumn) and regional (Nelson vs Hawke’s Bay) variations were not obvious in woody stems. A collection of 783 bacterial and 87 fungal endophytes were recovered from leaves and stems of ‘Royal Gala’, ‘Braeburn’, ‘Scilate’ and/or ‘Scifresh’ from Nelson (nine sites) and Hawke’s Bay (five sites) in spring and from Nelson (three sites) in autumn. A dual culture plating assay was used to test their ability to inhibit the mycelial growth of N. ditissima. Thirteen bacterial (mean of percent inhibition ≥20%) and 17 fungal isolates were antagonistic towards N. ditissima. These isolates belonged to the bacterial genera Bacillus and Pseudomonas, and fungal genera Chaetomium, Epicoccum, Biscogniauxia, Penicillium, Diaporthe, Phlyctema and two unidentified fungal isolates. Conclusions Endophyte communities in apple shoots were determined by tissue type, cultivar and site. Endophytic bacterial and fungal isolates inhibiting N. ditissima growth in vitro were found. Significance and Impact of the Study These results provided new evidence of factors influencing apple endophyte community in New Zealand. Endophytes with potential to reduce N. ditissima infection were identified, with the potential to be developed into a biocontrol strategy for European canker.

Fungal Communities in the Native New Zealand Medicinal Plant Pseudowintera colorata (Horopito) Are Determined by Plant Organ Type and Host Maturity with Key Members Promoting Plant Growth

“…Plant organ type was the main factor influencing the composition and richness of endophytic fungi in P. colorata and indicated that it is an overriding factor in the formation of endophytic fungal communities in P. colorata tissues. Similar findings were reported in other studies where tissue type primarily influenced the diversity and community structure of endophytic fungi [34,37].…”

“…The amplified PCR products were separated in 8% (w/v) polyacrylamide gel (acrylamide/bis solution, 37.5:1) with a linear gradient of 25-55% denaturant using a Cipher DGGE Electrophoresis system (CBS Scientific, Del Mar, CA, USA) [33]. Phoretix 1D Pro Gel Analysis (Totallab, Newcastle upon Tyne, UK) and Primer version 7 (Primer-E Ltd., Plymouth Marine Laboratory, Plymouth, UK) were used to analyze the endophytic fungal communities as previously described [34]. Each band in the DGGE gel was considered as one fungal taxon.…”

Bacterial Endophyte Community Dynamics in Apple (Malus domestica Borkh.) Germplasm and Their Evaluation for Scab Management Strategies

“…The extent of endophyte colonization in plants by endophytes was observed to be correlated to disease resistance [33]. Liu et al, [41] reported that the endophyte community-shaping in apple is being determined by the type of tissue, the sampling site, and cultivar, which in turn have a prominent impact on the number of potential antifungal biota strains present. The plant endosymbiosiomes have been widely used to isolate microflora with biocontrol ability [42] and the studies on such entities have revealed their abilities to contribute in conferring resistance to crops against various phytopathogens, including other substantial benefits on the host such as nutrient acquisition, enhanced growth, and improved resistance to heat, drought, and other stresses [43].…”

Characterization and Antagonistic Effect of Culturable Apple-Phyllosphere Endophytic Bacteria from the Cold Plateau in Yunnan, China

“…A culture-dependent analysis identified firmicutes of the genus Bacillus, Lysinibacillus, and Paenibacillus, and gammaproteobacteria of the genus Pseudomonas. There are some studies involving endophytes in reducing apple diseases, such as apple rot and European canker caused by Valsa mali and Neonectria ditissima, respectively, and the apple scab caused by Venturia inaequalis [11][12][13][14]. However, the ecological environment and cultivated varieties of apple-producing areas in Yunnan, China are different from those in northern China [2,15] and other apple-production areas in the world.…”

“…However, the ecological environment and cultivated varieties of apple-producing areas in Yunnan, China are different from those in northern China [2,15] and other apple-production areas in the world. Different varieties and ecological environments are bound to breed different communities of endophytic bacteria [12,16]. The endophytic bacteria in Yunnan are bound to be more suitable for the ecological environment of Yunnan than endophytic bacteria from other places.…”