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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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Fruit ripening and postharvest changes in very early–harvested tomatoes
Abstract It is well known that if a fruit is harvested extremely early its development and function are interrupted, and it may never attain full maturity and optimal quality. Reports revealing insights regarding the alterations of maturation, ripening and postharvest quality in very early picked fruits are rare. We examined the effects of early harvesting on tomatoes by characterizing different accessions at the molecular, physiological, and biochemical levels. We found that even very early–harvested fruits could achieve postharvest maturation and ripening though with some defects in pigment and cuticle formation, and seeds from very early–harvested fruits could still germinate and develop as normal and healthy plants. One critical regulator of tomato cuticle integrity, SlCER1–2, was shown to contribute to cuticle defects in very early–harvested fruits. Very early fruit harvest still allowing ripening and seed development indicate that the genetic and physiological programs of later maturation and ripening are set into motion early in fruit development and are not dependent on complete fruit expansion nor attachment to the plant.
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- Award ID(s):
- 1855585
- PAR ID:
- 10567270
- Publisher / Repository:
- Horticulture Research
- Date Published:
- Journal Name:
- Horticulture Research
- Volume:
- 11
- Issue:
- 9
- ISSN:
- 2052-7276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/hr/uhae199
