Transcriptome Analysis of the Fruit of Two Strawberry Cultivars "Sunnyberry" and "Kingsberry" That Show Different Susceptibility to Botrytis cinerea after Harvest

Int J Mol Sci. 2021 Feb 3;22(4):1518. doi: 10.3390/ijms22041518.

Abstract

Gray mold (Botrytis cinerea) is a fungal plant pathogen causing postharvest decay in strawberry fruit. Here, we conducted a comparative transcriptome analysis to identify differences in gene expression between the immature-green (IG) and mature-red (MR) stages of the "Sunnyberry" (gray mold-resistant) and "Kingsberry" (gray mold susceptible) strawberry cultivars. Most of the genes involved in lignin and alkane-type wax biosynthesis were relatively upregulated in "Sunnyberry". However, pathogenesis-related proteins encoding R- and antioxidant-related genes were comparatively upregulated in "Kingsberry". Analysis of gene expression and physiological traits in the presence and absence of B. cinerea inoculation revealed that the defense response patterns significantly differed between IG and MR rather than the cultivars. "Kingsberry" showed higher antioxidant induction at IG and upregulated hemicellulose-strengthening and R genes at MR. Hence, "Sunnyberry" and "Kingsberry" differed mainly in terms of the expression levels of the genes forming cuticle, wax, and lignin and controlling the defense responses. These discrepancies might explain the relative difference between these strawberry cultivars in terms of their postharvest responses to B. cinerea.

Keywords: cell wall; cuticle; gene expression; harvest; storage; strawberry fruit; transcriptome; wax.

MeSH terms

  • Antioxidants / metabolism
  • Botrytis*
  • Cell Wall
  • Fragaria / genetics*
  • Fragaria / metabolism
  • Fragaria / microbiology
  • Fruit / metabolism*
  • Fruit / microbiology
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant*
  • Mycoses / genetics*
  • Plant Diseases / genetics*
  • Plant Diseases / microbiology

Substances

  • Antioxidants

Supplementary concepts

  • Botrytis cinerea