INCREASED FUNGAL RESISTANCE OF TRANSGENIC PLANTS BY HETEROLOGOUS EXPRESSION OF BACTERIOPHAGE T4 LYSOZYME GENE
DJ STAHL1, A MASER1, J DETTENDORFER1/sup>, B HOLTSCHULTE2, JE THOMZIK3, R HAIN3 and R NEHLS1
1PLANTA GmbH, Grimsehistrasse 31, D-37574 Einbeck, Germany; 2KWS AG, Grimsehistrasse 31, D-37574 Einbeck, Germany; 3Bayer AG, PF-E/Fu, Institut fur Biotechnologie, D-51368 Leverkusen, Germany
Background and objectives
Results and conclusions
Resistance assays were performed under greenhouse conditions to evaluate the resistance level of the T4 lysozyme plants. Transgenic plants derived from different cultivars of summer- and winter-type oilseed rape exhibited an increased tolerance to Phoma lingam, the causal agent of blackleg disease. Resistance was evaluated by scoring the severity of stem cankers 2, 4, 6 and 8 weeks after inoculation. The resistance mechanism conferred by the T4 lysozyme gene seemed to be active all the time as shown by the temporal development of disease symptoms. Transgenic tomato plants showed an enhanced tolerance to Phytophthora infestans. The number of lesions and the spread of the fungus were reduced significantly on inoculated tomato leaves under high infection pressure.
These results indicate that the introduction of the T4 lysozyme gene into plants is a promising approach to improve fungal disease resistance. However, the molecular mechanism of resistance is still unknown. Experiments are in progress to describe the kind of resistance at the cellular and molecular level.