Sweet chestnut (Castanea sativa Miller) is a nutritious food with high social and economic
impacts in Portugal. The fungus Gnomoniopsis smithogilvyi (syn. Gnomoniopsis castaneae) is the causal
agent of chestnut brown rot, and is currently considered one of the major threats to the chestnut
production chain worldwide. Considering the lack of knowledge on both the disease and the
causal agent in Portugal, studies were conducted in an attempt to develop the necessary control
strategies towards the mitigation of the disease in a timely way. Isolates of G. smithogilvyi were
selected from three varieties of chestnut from the northeast of Portugal, and were characterized
at the morphological, ecophysiological and molecular levels. Tests of pathogenicity and virulence
were also developed. Gnomoniopsis smithogilvyi was confirmed as the causal agent of brown rot
disease in Portuguese chestnut varieties, which showed high susceptibility. The fungus showed high
adaptability to chestnut substrates. The Portuguese isolates of G. smithogilvyi are morphologically
and genetically similar to those from other countries, even though some physiological variability was
observed among them.
This work was funded by the project “ValorCast—Valorização da castanha e otimização
da sua comercialização”, ref. PDR2020-101-032030, funded by the Fundo Europeu Agrícola de Desenvolvimento
Rural (FEADER) and Portuguese Government, under the scope of Ação 1.1 «Grupos
Operacionais», Medida 1. «Inovação», PDR 2020—Programa de Desenvolvimento Rural do Continente,
as well as the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programe
PT2020 for financial support to CIMO (UID/AGR/00690/2020), SusTEC (LA/P/0007/2020),
CITAB (UID/AGR/04033/2020), and Inov4Agro (LA/P/0126/2020).
