In Memoriam Dr. Sherif A. Hassan †

On April 7, 2020, Dr. Sherif Hassan, for many years an employee and until his retirement Scientific Director of the Institute for Biological Control in Darmstadt, died at the age of 80 years.

Dr. Hassan was born on July 9, 1939, in Alexandria, Egypt. After completing his bachelor's degree in agricultural sciences at the University of Alexandria, he moved to the University of Edinburgh in Scotland, where he obtained his diploma in 1964 and his doctorate in 1967. Even at this early stage of his career, he was interested in biological control of agricultural pests and the possible side effects of pesticides on beneficial organisms. He always remained true to this topic in his further scientific work with a deliberate emphasis on practical applications of his research. In 1968 he took a position at the Plant Protection Service in Stuttgart, Germany, where he worked intensively on developing methods for the biological control of vegetable flies. Four years later, he moved to a newly created position at the Institute for Biological Crop Protection in Darmstadt, which gave him a platform to pursue his interest in linking sophisticated science with development of practical solutions for crop protection that could be applied in the field. Here, Sherif Hassan found the questions that fascinated him and whose challenges he successfully met with creative energy for more than 30 years until his retirement. His mission was to explore and develop methods for mass rearing and application of important beneficial insects, such as the lacewing Chrysoperla carnea, various predatory mites and the most important parasitoid of the white fly, Encarsia formosa. His main focus, however, became the smallest of them all - the egg parasitoid Trichogramma. In collaboration with scientific colleagues, plant protection services and beneficial insect producers around the world Dr. Hassan established Trichogramma as the most successful beneficial insect in important field crops such as corn and sugar cane. In addition, in the 1980s and 1990s – also in close cooperation with players from science, authorities, and industry - he developed standard methods for testing plant protection products for their side effects on beneficial organisms. These methods are widely applied today and form an essential part of regulatory testing procedures for newly developed active ingredients and plant protection products.

Dr. Sherif Hassan has written more than 200 scientific publications, several books and book chapters, and he was the founding editor of the "Egg Parasitoid News." Even more important to him than publishing his outstanding research results, was his goal to establish biological control using beneficial organisms as an environmentally friendly alternative to insecticides. To this end, he was always interested in developing cost-effective and efficient methods that are attractive to the farmers that apply them on a daily basis. He sought - and found - allies worldwide that helped him work towards this goal.

Aside from his own scientific achievements, Dr. Hassan made major contributions to the field by coordinating and taking responsibility for important research tasks as head of various national and international working groups. It was extremely important to him to bring people together to advance research in biological control. In Germany, he was a founding member and long-standing chairman of the working group "Beneficial arthropods and entomopathogenic nematodes" under the umbrella of the German Society of general and applied Entomology (DGaaE) and the German Society for Plant Protection and Plant Health (DPG). Internationally, under the auspices of the IOBC-Global (International Organisation for Biological Control), he founded the working group "Trichogramma and other egg parasites," which brought together scientists through regularly organised conferences as well as the already mentioned "Egg Parasitoid News," connecting their activities in the best possible way. The working group "Pesticides and Beneficial Organisms" of the IOBC-West Palaearctic Regional Section, which he headed for many years, very successfully promoted the development of standard testing procedures and methods to evaluate possible side effects of plant protection products on beneficial organisms. This group coordinated international joint ring-testing programmes, validated test methods, and later used these methods to classify numerous plant protection products with regard to their possible side effects. These results were of exceptional importance for the advancement of selective plant protection products in integrated pest management and for reducing their impact on non-target organisms. With further development and validation at the international level, these guidelines have become indispensable in the registration process of plant protection products, both nationally and in the European Union.

In addition to his extraordinary scientific talent, Dr. Sherif Hassan distinguished himself above all by his ability to bring people together and work with them towards a common goal. This was also due to his openness to the world and his great humanitarianism. Sherif Hassan was a networker and multiplier par excellence. He travelled the world to meet colleagues in numerous countries in Europe, Asia, Africa, and South America to successfully promote biological control based on beneficial arthropods - especially Trichogramma. And the world came to Darmstadt - his laboratory was always brimming with students, visitors, and guest scientists from around the world studying current questions in biocontrol. Sherif Hassan was always a modest, polite and an inspiring mentor - the involvement and success of young scientists was particularly important to him. Many of his doctoral students successfully found their way into science and are now active in science, research, and running beneficial insect producers around the globe. He opened up opportunities for dialogue at conferences and by working to obtain scholarships from the German Academic Exchange Service, the Alexander von Humboldt Foundation, and other funding organisations. His passionate commitment and his outstanding achievements in biological control have led to his name being held in the highest esteem worldwide - and will remain so forever.

In 2004, Dr. Sherif Hassan took his well-deserved retirement. But even in retirement he always remained respectfully and warmly attached to the Institute for Biological Control, the Federal Biological Research Centre for Agriculture and Forestry and, of course, the Julius Kühn-Institut and all its staff. He remained active in research - for example in 2010 and 2011, when he travelled to Uzbekistan on behalf of the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) and advised research institutions and authorities on how biological control using Trichogramma can work. He has received numerous awards for his life's work - most recently, the German Society for Plant Protection and Plant Health awarded him the Anton de Bary Medal, which was presented to him during the German Plant Protection Conference in 2014.

Born and raised in Alexandria, Dr. Sherif Hassan was a child of the sea and naturally very fond of water sports, especially sailing and swimming. After his retirement he continued to practice these sports enthusiastically and even competed in them. For decades, he and his wife Johanna have also been privately involved in intercultural exchange, especially in the "Circle of German-Egyptian Friends" in Darmstadt. As a happy family man and father of two sons, he also took on the duties of a grandfather with pleasure. Even these duties, however, have not prevented him from continuing to play a part in the fate of the Trichogramma - advising on the biological control of the European Corn Borer and also studying the impact of extreme hot summer temperatures on the effectiveness of these beneficials in the field. His sudden and unexpected death tore Dr. Sherif Hassan out of a much fulfilled, very active life still dedicated to science. We will sorely miss his valuable advice and his warm and life-affirming personality. We will always honour his memory. Our deepest sympathy goes to his family.

Annette Herz, Heidrun Vogt and Johannes Jehle
Julius Kühn-Institut