The Role of Crop Rotation Systems on Non-Cyst Nematodes Affecting Potatoes in the Temperate Zones

Abstract

Plant-parasitic nematodes have a significant economic impact on potato production in the temperate zones. The most damaging nematodes on potatoes are the potato cyst nematodes, Globodera pallida and G. rostochiensis. Of the non-cyst nematodes (NCN), the potato rot (Ditylenchus destructor), root-lesion (Pratylenahus penetrans), root-knot (Meloidogyne spp.) and stubby-root (Paratriehodorus and Trichodorus spp.) nematodes are most important. Literature on NCN problems in potato production, of which the occurrence or effect depends on crop rotation systems or cropping frequency, is limited. This is due to the wide host range of NCN, which makes crop rotation impractical. Thus, the most common means to control NCN on potatoes is by the use of nematicides. However, in the USSR crop rotation with adequate weed control, use of clean seed, and planting potatoes every 3 or 4 years had been reported to satisfactorily control D. destructor. In the northwestern United States, a three-year crop rotation along with nematicides is used to control M. chitwoodi and M. hapla on potatoes. Monoculture with potatoes has been shown to reduce the efficacy of soil fumigants in controlling M. chitwoodi. Crops commonly grown in rotation with potatoes in the northwestern United States are alfalfa and cereals. The cereals are used to suppress M. hapla populations but are good hosts for M. chitwoodi. Alfalfa is a good host for M. hapla and M. chitwoodi race 2 but unsuitable for race 1. Thus, a major part of the problems encountered with M. chitwoodi on potatoes is due to an inadequate crop rotation system.