The control of potato pale cyst-nematode (Globodera pallida) by chemical and cultural methods in different soils

Abstract

SummaryIn 12 field experiments in England (1985, 1991 and 1992), on soils infested with potato pale cystnematode (Globodera pallida), oxamyl increased yields of susceptible and partially-resistant potatoes and lessened nematode multiplication at some sites but not others. Attempts to explain these site differences were unsuccessful. In a heavily infested peaty loam, large amounts of aldicarb or oxamyl, smaller amounts of both conjointly or 6·8 kg oxamyl/ha incorporated in the top 10 cm of the soil were needed to prevent G. pallida multiplication on susceptible Wilja potatoes. In three experiments, 1,3-dichloropropene at 250 or 225 1/ha increased tuber yields more than oxamyl did but had little or no effect on G. pallida multiplication. Ethoprophos at 11 kg/ha or fosthiezate at 4 kg/ha lessened G. pallida multiplication on Désirée potatoes in a silt loam soil but not in a peaty loam soil.The multiplication of G. pallida was reliably controlled in ten experiments by partially-resistant Morag or Santé potatoes. Soil population densities of G. pallida were greatly decreased by one or two crops of Cara potatoes uprooted when the first female nematodes were visible on the roots.It is concluded that granular nematicides and 1,3-dichloropropene are best employed to lessen injury to susceptible and partially-resistant potatoes and that G. pallida increase is best controlled by partially-resistant potatoes protected by a nematicide. Soil infestation levels can be decreased rapidly by soil fumigation or trap cropping with Cara potatoes.