Plants (Mar 2023)

Stress Response to Climate Change and Postharvest Handling in Two Differently Pigmented Lettuce Genotypes: Impact on <i>Alternaria alternata</i> Invasion and Mycotoxin Production

  • Jon Miranda-Apodaca,
  • Unai Artetxe,
  • Iratxe Aguado,
  • Leire Martin-Souto,
  • Andoni Ramirez-Garcia,
  • Maite Lacuesta,
  • José María Becerril,
  • Andone Estonba,
  • Amaia Ortiz-Barredo,
  • Antonio Hernández,
  • Iratxe Zarraonaindia,
  • Usue Pérez-López

DOI
https://doi.org/10.3390/plants12061304
Journal volume & issue
Vol. 12, no. 6
p. 1304

Abstract

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Many species of Alternaria are important pathogens that cause plant diseases and postharvest rots. They lead to significant economic losses in agriculture and affect human and animal health due to their capacity to produce mycotoxins. Therefore, it is necessary to study the factors that can result in an increase in A. alternata. In this study, we discuss the mechanism by which phenol content protects from A. alternata, since the red oak leaf cultivar (containing higher phenols) showed lower invasion than the green one, Batavia, and no mycotoxin production. A climate change scenario enhanced fungal growth in the most susceptible cultivar, green lettuce, likely because elevated temperature and CO2 levels decrease plant N content, modifying the C/N ratio. Finally, while the abundance of the fungi was maintained at similar levels after keeping the lettuces for four days at 4 °C, this postharvest handling triggered TeA and TEN mycotoxin synthesis, but only in the green cultivar. Therefore, the results demonstrated that invasion and mycotoxin production are cultivar- and temperature-dependent. Further research should be directed to search for resistant cultivars and effective postharvest strategies to reduce the toxicological risk and economic losses related to this fungus, which are expected to increase in a climate change scenario.

Keywords