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The filamentous fungus Fusarium graminearum is a well-known cereal pathogen and F. avenaceum is a pathogen with a wide host range. Recently, both species were reported as causal agents of apple rot, raising concerns about postharvest yield losses and mycotoxin contamination. Here, we report genome assemblies of F. avenaceum KA13 and F. graminearum TaB10, both isolated from fruits with symptoms of apple rot. The final F. avenaceum KA13 genome sequence assembly of 41.7 Mb consists of 34 scaffolds, with an N 50 value of 2.2 Mb and 15,886 predicted genes. The total size of the final F. graminearum TaB10 assembly is 36.76 Mb, consisting of 54 scaffolds with an N 50 value of 1.7 Mb, and it consists of 14,132 predicted genes. These new genomes provide valuable resources to better understand plant-microbe interaction in stored apple rot disease. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .
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This content will become publicly available on April 21, 2026
Temporal fruit microbiome and immunity dynamics in postharvest apple ( Malus x domestica )
Abstract The plant immune response plays a central role in maintaining a well-balanced and healthy microbiome for plant health. However, insights into how the fruit immune response and the fruit microbiome influence fruit health after harvest are limited. We investigated the temporal dynamics of the fruit microbiota and host defense gene expression patterns during postharvest storage of apple fruits at room temperature. Our results demonstrate a temporal dynamic shift in both bacterial and fungal community composition during postharvest storage that coincides with a steep-decline in host defense response gene expression associated with pattern-triggered immunity. We observed the gradual appearance of putative pathogenic/spoilage microbes belonging to genera Alternaria (fungi) and Gluconobacter and Acetobacter (bacteria) at the expense of Sporobolomyces and other genera, which have been suggested to be beneficial for plant hosts. Moreover, artificial induction of pattern-triggered immunity in apple fruit with the flg22 peptide delayed the onset of fruit rot caused by the fungal pathogen Penicillium expansum. Our results suggest that the fruit immune response helps to orchestrate a microbiome and that the collapse of the immunity results in the proliferation of spoilage microbes and fruit rot. These findings hold implications for the development of strategies to increase fruit quality and prolong shelf life in fruits and vegetables.
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- Award ID(s):
- 2208939
- PAR ID:
- 10589065
- Publisher / Repository:
- Horticulture Research
- Date Published:
- Journal Name:
- Horticulture Research
- Volume:
- 12
- Issue:
- 6
- ISSN:
- 2052-7276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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