Nematology

Courtesy professor Dr. Johannes Hallmann is head of the Institute of Epidemiology and Pathogen Diagnostics, Julius Kühn-Institut, Federal Research Center for Cultivated Plants, Braunschweig. In research and teaching, the field of nematology focuses on plant parasitic nematodes, in particular their biology, distribution and damage to crops as well as possible control measures. In addition, the importance of free-living nematodes for the agroecosystem receives increasing attention. Free-living nematodes are of pivot importance for the soil food web and nutrient mineralization and are relevant indicators for soil health and sustainable soil management. Other research fields include the interactions of plant parasitic nematodes with nodule bacteria and soil-borne pests, as well as the development of sustainable strategies to reduce the damage caused by plant parasitic nematodes.

Nematodes are the most numerous multicelluar animals on earth. Within 100 ml fertile soil more than 10,000 nematodes can occur. Most nematodes feed on bacteria and fungi thus playing a significant role in nutrient mineralization and within the soil food web. Other nematodes parasitize insects and are successfully used for biological control (e. g. Heterorhabditis, Steinernema). Nonetheless, some nematodes also feed on plant roots. Nematode infested roots will get damaged and water and nutrient uptake is disturbed. Plant organs stay small or are deformed, yields are reduced. Overall qualitative or quantitative losses can be high and even lead to complete loss of the crop. In order to efficiently control plant-parasitic nematodes, accurate identification is required as well as a good understanding of their biology, host plant spectrum and natural antagonists within the soil ecosystem. Accordingly, research interest focuses on method development, taxonomy, biology and management of plant-parasitic nematodes. Main activities are in horticultural crops, but arable crops as well as sports greens are also covered. The group Nematology is international oriented working in temperate as well as tropical/subtropical environments.

Examples of on-going research activities are:

• Occurrence and damage potential of plant-parasitic nematodes in organic farming
• Interaction between root-knot nematodes (Meloidogyne) und root-lesion nematodes (Pratylenchus) with rhizobia on legumes
• Biology and damage potential of ectoparasitic nematodes (e. g. Paratylenchus, Trichodorus)
• Sustainable nematode management using subsidiary crops
• Mode-of-action of biocontrol organisms

The teaching is aiming at the importance of nematodes in the soil ecosystem. Besides covering free-living and entomopathogenic nematodes, main emphasis will be given to plant-parasitic nematodes as a major threat to crops worldwide. All relevant aspects from soil sampling and nematode extraction to nematode identification and their control will be treated in lectures and practical. Based on the biology of the nematode sustainable management strategies will be developed for major crops in temperate as well as tropical/subtropical crops and in conventional as well as organic farming. Examples from praxis will be presented and discussed under various factors such as climate change and globalization.

Plant Nematology (M.SIA.P20, 6 C, 4 SWS, block course in September, 50% lectures, 50% practicals): of fered within the MSc programme Sustainable International Agriculture (SIA), also open for other students