Mechanisms of nematode resistance in catch crops (AALTJESRESMECH)

The root-knot nematode Meloidogyne chitwoodi, a quarantine organism in Belgium, can cause severe yield reductions in various crops, including maize, potato, tomato, sugar beet carrot and scorzonera. Controlling this disease is difficult because of the lack of usable pesticides. By including a nematode resistant green manure crop such as fodder radish in the crop rotation, the nematode population in the soil can be lowered to diminish the disease pressure. Yet breeding fodder radish for resistance against M. chitwoodi is hampered by the lack of knowledge on the resistance mechanism. Therefore, this project investigates the resistance mechanism of fodder radish to M. chitwoodi in detail.

 

Seedlings from various populations of fodder radish are inoculated with J2 larvae, free-living infectious larvae from larval stage 2, from M. chitwoodi in controlled conditions. Tomato plants are used as positive control. After inoculation, the infection process is studied: do the J2 larvae enter the roots, do we observe a feeding site being formded, do the larvae develop into adult females and do these females produce egg masses? The differences between the fodder radish populations are studied. Afterwards, the lab results are confirmed in a field trial.

 

The results are published in scientific journals and are used to optimize the screening method for resistant plants. This may lead to a more rapid, worldwide development of fodder radish cultivars with a better and more durable resistance against the root-knot nematode.