Crop losses by insects and the problem of control.

Food losses in field and store 5 cause outstanding losses in many crops. Because there are few trained nematologists, many other important nematode problems on key food crops such as rice and paddy remain uninvestigated. Because nematodes are soil organisms, control is especially difficult. Few satisfactory nematicides are known and these are too expensive for most agricultural crops in Europe. For these reasons, control is largely based on knowledge of host ranges, crop rotation, use of resistant varieties and eradication of weed hosts. Hotwater treatment of bulbs, stools or runners is also practised. These methods are valuable but are not always convenient or sufficiently effective. Chemical control at economic prices is the ultimate goal.