29 May 1998

Nematode control hit by leaching

REDUCED nematicide efficacy due to leaching could hit growers who planted their potatoes early this year, warns Pat Haydock of the Crop and Environmental Research Centre at Harper Adams Agricultural College.

In areas with light textured soils, many growers took advantage of dry weather in March to plant their second earlies. Land with a history of PCN was typically treated with a granular nematicide immediately before planting.

"But with the wettest April on record and soils at field capacity for most of the month, there is a strong chance that water-soluble, active ingredients in nematicides have been leached below the region of early root growth," says Dr Haydock.

"It is vital growers monitor nematode populations carefully to assess the severity of the problem. Future rotations, variety selection and crop husbandry could all be affected." &#42