In vitro effectiveness of difenoconazole against Itersonilia perplexans Derx

  • Giovanni BubiciEmail author
  • Maria Isabella Prigigallo
  • Mario Amenduni
Short Communication


Leaf blight caused by Itersonilia perplexans Derx is commonly observed on dill (Anethum graveolens L.) at the crop maturity stage. In the fields of southern Italy, I. perplexans attacks begin in late autumn, when the weather is cool and humid. In laboratory, the fungal growth rate was maximum at 20 °C, the ballistoconidia production was null at temperatures of 25 °C or higher, and growth was interrupted at 30 °C or above. It is difficult to manage the disease because very few fungicides are admitted for use on dill. Therefore, we screened in vitro several fungicides for their toxicity against I. perplexans, and discovered the high effectiveness of difenoconazole, with EC50 and EC95 of 0.5 and 0.95 μg mL−1, respectively, both for mycelium growth and ballistoconidia production. Ciprodinil+fludioxonil, azoxystrobin (both with EC50 = 0.69 μg mL−1) and boscalid (EC50 = 7.32 μg mL−1) were toxic to I. perplexans, but did not suppress completely the pathogen even at doses of 10,000 μg mL−1. Mancozeb+metalaxil showed EC50 of 15.5 μg mL−1 and completely suppressed the fungus at 100 μg mL−1. Copper oxychloride was toxic only at doses higher than 100 μg mL−1, and sulphur did not affect the pathogen growth. Therefore, difenoconazole is worthy of further evaluations in the field for the control of leaf blight of dill caused by I. perplexans.


Itersonilia perplexans Dill Anethum graveolens Chemical control Difenoconazole 


Compliance with ethical standards

Conflict of interest

Giovanni Bubici declares that he has no conflict of interest. Maria Isabella Prigigallo declares that she has no conflict of interest. Mario Amenduni declares that he has no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.


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Copyright information

© Società Italiana di Patologia Vegetale (S.I.Pa.V.) 2018

Authors and Affiliations

  1. 1.Consiglio Nazionale delle Ricerche (CNR)Istituto per la Protezione Sostenibile delle Piante (IPSP)BariItaly
  2. 2.Dipartimento di Scienze del Suolo, della Pianta e degli AlimentiUniversità degli Studi di Bari ‘Aldo Moro’BariItaly

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