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Societal Impact StatementGroundcherry (Physalis grisea) is a plant species grown for its flavorful fruit. The fruit drops from the plant, hence the common name groundcherry. This makes harvest cumbersome and puts the fruit at risk for carrying soil‐borne pathogens, therefore making them unsellable. Furthermore, insects often damage the plants, reducing yield. Advances in gene editing offer promise for addressing these issues and aiding home gardeners and farmers. Improvement will expand access to this nutritious fruit, rich in potassium, vitamin C, and antioxidants. Additionally, studies of its biology could serve as a model for improving other fruiting plants, particularly underutilized species. SummaryP. griseais an underutilized, semidomesticated fruit crop with rising agronomic value. Several resources have been developed for its use in fundamental biological research, including a plant transformation system and a high‐quality reference genome. Already,P. griseahas been used as a model to investigate biological phenomena including inflated calyx syndrome and gene compensation.P. griseahas also been used to demonstrate the potential of fast‐tracking domestication trait improvement through approaches such as CRISPR/Cas9 gene editing. This work has led to thePhysalisImprovement Project, which relies on reverse genetics to understand the mechanisms that underlie fruit abscission and plant–herbivore interactions to guide approaches for improvement of undesirable characteristics. CRISPR/Cas9 gene editing has been used to targetP. griseagenes that are suspected to act in fruit abscission, particularly orthologs of those that are reported in tomato abscission zone development. A similar approach is being taken to targetP. griseagenes involved in the withanolide biosynthetic pathway to determine the impact of withanolides on plant–herbivore interactions. Results from these research projects will lead to a greater understanding of important biological processes and will also generate knowledge needed to develop cultivars with reduced fruit drop and increased resistance to insect herbivory.
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Genetic and metabolic effects of ripening mutations and vine detachment on tomato fruit quality
Summary Tomato (Solanum lycopersicum) fruit ripening is regulated co‐operatively by the action of ethylene and a hierarchy of transcription factors, includingRIPENING INHIBITOR(RIN) andNON‐RIPENING(NOR). Mutations in these two genes have been adopted commercially to delay ripening, and accompanying textural deterioration, as a means to prolong shelf life. However, these mutations also affect desirable traits associated with colour and nutritional value, although the extent of this trade‐off has not been assessed in detail. Here, we evaluated changes in tomato fruit pericarp primary metabolite and carotenoid pigment profiles, as well as the dynamics of specific associated transcripts, in therinandnormutants during late development and postharvest storage, as well of those of the partially ripeningdelayed fruit ripening(dfd) tomato genotype. These profiles were compared with those of the wild‐type tomato cultivars Ailsa Craig (AC) and M82. We also evaluated the metabolic composition of M82 fruit ripened on or off the vine over a similar period. In general, thedfdmutation resulted in prolonged firmness and maintenance of quality traits without compromising key metabolites (sucrose, glucose/fructose and glucose) and sectors of intermediary metabolism, including tricarboxylic acid cycle intermediates. Our analysis also provided insights into the regulation of carotenoid formation and highlighted the importance of the polyamine, putrescine, in extending fruit shelf life. Finally, the metabolic composition analysis of M82 fruit ripened on or off the vine provided insights into the import into fruit of compounds, such as sucrose, during ripening.
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- Award ID(s):
- 1855585
- PAR ID:
- 10459391
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Plant Biotechnology Journal
- Volume:
- 18
- Issue:
- 1
- ISSN:
- 1467-7644
- Format(s):
- Medium: X Size: p. 106-118
- Size(s):
- p. 106-118
- Sponsoring Org:
- National Science Foundation
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