Nematode pests of potato and other vegetable crops

Abstract

The major nematode pests of potato and tomato, their biology, economic damage and control options are outlined along with brief descriptions of those recorded from onion, cabbage, carrot, sweet potato, green pea, beetroot and green pepper. Root-knot nematodes, especially Meloidogyne incognita and Meloidogyne javanica, are the most damaging on all these crops, though other genera and species are also listed. In South Africa, potato is the major vegetable crop that experiences nematode problems, with Meloidogyne spp., Globodera rostochiensis and Pratylenchus brachyurus being the most economically important pests. In 1996, six Meloidogyne spp. were reported as infecting potato, to which Meloidogyne enterolobii was added in 2013. Pratylenchus brachyurus has been identified from all local potato-growing areas. Globodera rostochiensis was first identified around Pretoria and Johannesburg in Gauteng Province in 1971. The introduction and implementation of strict quarantine restrictions led to the eradication of G. rostochiensis at these sites. Regrettably in 1999, a second outbreak was identified in Ceres (Western Cape Province), and quarantine measures are still in place to attempt to contain this outbreak. Tomato is also severely damaged by root-knot nematodes, and the results of several micro-plot experiments testing the population dynamics, the impact of susceptible and resistant cultivars and yield interactions of Meloidogyne spp. on the crop are reported. Other nematode problems reported on various other vegetable crops are Heterodera schachtii on cabbage and beetroot, Nanidorus minor on onion and Paratrichodorus lobatus on sweet potato