Carrot cavity spot: the effects of non-carrot crops on levels of relevant Pythium spp in the soil

Phythium violae has a broad host range amongst both wild (weed) and cultivated species which means that long rotations out of carrots will not ensure freedom from cavity spot.

Pre-carrot rotations can affect levels of cavity spot disease (potatoes reduced cavity spots by 65 - 70% in two out of three trials).

"Companion" planting can affect the levels of cavity spot disease, barley was one of the two most effective "companions" - this crop is already used as a nurse crop by some growers without unacceptable losses and further studies on relative planting times may produce a commercially acceptable system.