Johannes Köhnlein

Johannes Köhnlein (born October 18, 1902 in Attabey , Turkey ; † September 15, 1989 in Kiel ) was a German arable and crop scientist .

Life

Johannes Köhnlein, son of a farmer, studied agriculture at the University of Jena and received his doctorate there in 1925 with a thesis on poultry mites . In 1926 he passed the test to become a seed breeding manager and then worked for several years as an agriculture teacher and economic consultant in Gotha. From 1931 to 1938 he worked as a consultant for seed breeding, fodder cultivation, state culture and fertilization at the main chamber of agriculture and state farming community in Thuringia in Weimar. From 1939 to 1942 he was head of the arable farming department of the Sudetenland rural farming community.

In 1943, Köhnlein took over as professor and director of the Institute for Forage Production at the Prussian Experimental and Research Institute for Dairy Farming in Kiel. This institute was founded in 1935 as the successor to the Institute for Plant Cultivation and Plant Breeding, which was part of the Philosophical Faculty of the University of Kiel. With the establishment of an agricultural faculty at the University of Kiel in May 1946, Köhnlein was additionally entrusted with the management of a newly founded institute for plant cultivation and plant breeding. Here he worked as a full professor until his retirement in 1969.

Research services

Köhnlein's research focus was the nutrient and humus cycle in agricultural businesses in connection with forage production . He carried out long-term fertilization trials at several test sites in Schleswig-Holstein. With the help of lysimeters, he quantified the nutrient dynamics in agriculturally used soils and gained new insights into the leaching of nutrients from the topsoil with different uses and fertilization. Almost all of his scientific work has a strong practical relevance. He has published numerous articles on the humus balance of arable soils and its importance for soil fertility in the "Series of publications by the Faculty of Agriculture at the University of Kiel".

In connection with his attempts to promote soil fertility, Köhnlein paid particular attention to the root growth of agricultural crops. His book “Harvest residues and root pattern” , published together with Heinz Vetter in 1953 , has been one of the standard works of specialist plant cultivation literature for several decades. His research on the role of plant roots and earthworms in poring through the subsoil deserves special attention .

Köhnlein's most important contribution to the field of fodder construction is his textbook "Grundriß der fodderbaulehre" published in 1971 . This work also contains the most important results of his own research on forage crops. Köhnlein had been a member of the committee for grassland and forage production of the German Agricultural Society since 1947 and since 1954 co-editor of the magazine “Das Wirtschaftseigene Futter”.

Fonts (selection)

• The bird mite (Dermanyssus avium) and how to combat it . Diss. Phil. Jena 1925. Zugl. in: Archive for Scientific and Practical Veterinary Medicine, Vol. 53, 1925, pp. 144–180.
• Ways to improve the humus supply of our mineral soils . Series of publications by the Faculty of Agriculture at Kiel University, issue 9, 1953.
• Crop residues and root appearance. Amount and nutritional content of the remains of the most important cultivated plants on the field (with Heinz Vetter). Publisher Paul Parey Hamburg and Berlin 1953.
• The pores and roots of the subsoil . In: Series of publications by the Faculty of Agriculture at the University of Kiel H. 14, 1955, pp. 3–41.
• Results of the Kiel permanent fertilization tests with phosphate and potash (with Norbert Knauer). Series of publications by the Faculty of Agriculture at the University of Kiel H. 39, 1965.
• Floor plan of the lining theory . Publisher Eugen Ulmer Stuttgart 1971.
• The Institute for Forage Production and the Institute for Plant Production and Plant Breeding in Kiel from 1943 to 1970 . (Typewriter) Kiel 1973. - Noteworthy documentation on the history of crop science with a chronological compilation of the most important publications by Köhnlein and a list of the dissertations he wrote.

literature

• Adolf Stählin: Johannes Köhnlein on his 65th birthday . In: Das Wirtschaftseigene Futter vol. 13, 1967, pp. 269-270.
• Norbert Knauer: On the 80th birthday of Professor Dr. Johannes Köhnlein . In: Zeitschrift für Acker- und Pflanzenbau Vol. 151, 1982, pp. 322-324 (with picture).
• Norbert Knauer: In memoriam Johannes Köhnlein . In: Christina Albertina, New Series H. 30, 1990, pp. 451–452.

Web links

• Literature by and about Johannes Köhnlein in the catalog of the German National Library