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Reduction of rot losses in apples - insights into infection conditions and early detection of storage rots

PhD defence, Thursday 9 September 2021, Hinrich Hermann Ferdinand Holthusen

2021.09.09 | Helle Mitzi Thomsen Reichl

Hinrich Hermann Ferdinand Holthusen

(A) Sporulating lesions of bull’s eye rot caused by N. perennans and (B) fully developed symptoms of rubbery rot caused by P. washingtonensis on an apple fruit in cold storage at atmospheric air. (Photographs: Hinrich H. F. Holthusen).

During his PhD studies, Hinrich H. F. Holthusen conducted research on the infection biology and influencing phenological and environmental parameters of selected rot-causing fungi of apple fruit. For blossom-end rot, caused by Neonectria ditissima, the phenological stages during flowering most conducive to infection were established by inoculation experiments. For the storage-rot fungi Neofabraea perennans and Phacidiopycnis washingtonensis phenological stages of the fruit or environmental parameters at the time of inoculation that influence the incidence of storage rot were determined. Furthermore, Hinrich H. F. Holthusen studied how the development of rubbery rot cause by P. washingtonensis could be detected early during storage by monitoring emission of volatile organic compounds.

The new research results contribute to the understanding of the phenology of fruit development and the environmental conditions that lead to infections of apples with rot-causing fungi in the orchard, and how the development of storage rots can be modelled before harvest, and indirectly monitored during storage.

The PhD study was completed at the Department of Food Science, Faculty of Technical Sciences, Aarhus University.

This summary was prepared by the PhD student.

Time: Thursday, 9 September 2021 at 13:00
Place: Room 5910-214, Department of Food Science , Aarhus University, Agro Food Park 48, DK-8200 Aarhus N
To receive a link to the event, please send an e-mail to Sarah Lee Nielsen: sn@food.au.dk
Title of PhD thesis: Infection biology and early detection of fungi causing fruit rot of apple

Contact information: Hinrich H. F. Holthusen, e-mail: hinrich.holthusen@lwk-niedersachsen.de, tel.: +49-151-50191674

Members of the assessment committee:

Ph.D., Research Scientist Jorunn Børve, Department of Fungal Plant Pathology in Forestry, Agriculture and Horticulture, Norwegian Institute of Bioeconomy Research, Norway

Ph.D., Associate Professor Mikael Agerlin Petersen, Department of Food Science, Copenhagen University, Denmark

Ph.D., Associate Professor Marianne Hammershøj (chair), Department of Food Science, Aarhus University, Denmark

Main supervisor:
Ph.D., Associate Professor Merete Edelenbos, Department of Food Science, Aarhus University, Denmark

Ph.D., Affiliated Professor Roland W. S. Weber, Department of Food Science, Aarhus University, Denmark and Department of Integrated Plant Protection and Diagnostics, Chamber of Agriculture Lower Saxony, Esteburg Obstbauzentrum Jork, Germany
Language: The PhD dissertation will be defended in English

The defence is public.
Due to the coronavirus situation, the PhD thesis will not be available for reading at the offices of the PhD administration. Instead, interested parties may send an e-mail to gradschool.tech@au.dk to receive a digital copy of the PhD thesis. Please note, it may in certain cases be necessary to make an individual arrangement to read the PhD thesis.

PhD defence
17427 / i43