2025/09/01 by Connor Lane, Yosef Al Shoffe, Michael G. Brown +5 · 1 voice · 1 citation
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Plant Pathogens and Fungal Diseases #Plant Physiology and Cultivation Studies #Postharvest Quality and Shelf Life Management
paper · doi:10.21273/jashs05521-25
openalex publication_date 2025/09/01 · openalex created_date 2025/09/18 · openalex updated_date 2026/06/26
Fruit microbiomes are capable of protecting their hosts from harmful pathogens and aiding in biocontrol; therefore, it is important to understand how differences in host genotype shape fruit microbial communities. The fruit species and even cultivars within a species can harbor different fruit microbiomes, but it has been difficult to establish how a single host gene can shape the microbiome structure. We investigated two genotypes of ‘Greensleeves’ apples with reduced sorbitol biosynthesis through antisense suppression of aldose 6-phosphate reductase with the wild type (WT) to assess how sugar composition of the fruit surface impacts microbial communities. We hypothesized that reduced sorbitol genotypes A4 and A10 would show an epiphytic microbiome different from that of the WT that corresponds to a difference in sugar composition on the fruit surface at harvest and during storage with and without postharvest treatment of fruit with 1-methycyclopropene (1-MCP), which is an inhibitor of ethylene perception. Throughout the sampling window (at harvest, 7 weeks storage, 13 weeks storage) across the 2 years of the study, the genotype, but not 1-MCP, was a significant predictor of microbiome composition. The A10 and A4 lines had an increased abundance of the pathogenic fungal genus Acremonium compared with that of the WT in one year. However, while A4 and A10 had different sugar compositions than that of WT in fruit flesh, no differences on the fruit surface were found. In addition, A4 and A10 showed microbiomes that were different from each other as well as different from that of the WT despite having the same reduced sorbitol phenotype, thus making it difficult to link microbiome differences to a specific physiological mechanism. This work represents an important step in showing the first example, to our knowledge, of how the cascading effects resulting from silencing a single gene can impact the assembly of postharvest fruit microbiomes.