Some species of plant-parasitic nematodes are a significant constraint to carrot production.
Root knot nematode (RKN) (Meloidogyne spp.) is the most damaging to many carrot crops in Australia. RKN can cause seedling death, stunting of young plants, branching of tap roots and galling in older plants, which reduces quality and yield.
Lesion nematode (Pratylenchus spp.), and other nematodes such as Hemicyliophora saueri and Neodolichodorus australis, can also cause crop losses when present in high numbers.
Nematode control in Australia is heavily reliant on general soil fumigants. Nematicides should be used judiciously as they tend to be costly, highly toxic and potentially environmentally harmful. Additionaly, continual use of the same chemical can lead to microorganism build-up that can rapidly render them ineffective – a process known as ‘enhanced microbial degradation’.
- Know your enemy and conduct a soil test
- Sample intensively to get a representative count
- Use nematicides in conjunction with a soil test
- Plan rotations with crops that are poor nematode hosts or with biofumigant crops.