Plant pathogenic nematodes are a major pest in crop production in the European Community and cause considerable losses in yield every year. Since crop rotation cannot fully overcome the nematode problem, large amounts of nematicides are used to control the nematode populations. However, since the use of nematicides contributes significantly to the pollution of the environment, introduction of resistant crop species is highly desirable. This proposal concerns the isolation of a plant nematode resistance gene, a detailed analysis of the mode of action of such a gene, the introduction of the gene into selected crop species and a homology search for further nematode resistance genes with agricultural importance. The gene of choice to be isolated is the bcn gene from wild beet of the section Procumbentes, which confers resistance against the beet cyst nematode Heterodera schachtii. This gene is one of the best studied nematode resistance genes nowadays, making it very suitable for molecular cloning.
The project will be carried out in three distinct phases. the first two phases will concern the isolation of the bcn gene using a reversed genetics approach: In the first phase detailed restriction maps and genetic maps will be constructed of the bcn-loci in resitant B. vulgaris fragment addition lines. Also, existing YAC libraries of selected fragment addition lines will be completed. In the second phase the YAC libraries will be screened with available molecular markers for the bcn gene and a chromosomal walk towards the gene will be conducted. Candidate genes will be isolated and the bcn gene will be identified by a functional analysis after introduction of the candidates into sugar beet hairy roots and Arabidopsis. Finally in the third phase a thorough analysis of the bcn gene will be made and crop plants susceptible to H.schachlii, like sugar beet and rape seed, will be transformed with the gene to obtain resistant varieties. Also the gene will be used to search for additional plant encoded nematode resistance genes which can be introduced into several other important crop species like potatoes and tomatoes. The application of nematode: resistant crop plants will contribute significantly to the reduction in the use of pesticides in the EC. Also, the obtained expertise will be of great value for the isolation of further disease resistance genes from plants.
Funding SchemeCSC - Cost-sharing contracts