Abstract

The use of root-knot (Meloidogyne spp.) nematode resistance in most crops remains the most preferred option, but there are no known genotypes with nematode resistance in wild and cultivated potato (Solanum tuberosum) plants. As part of concerted efforts to search for nematode resistance, the objective of this study was to determine the hoststatus of high yielding commercial potato cultivars in South Africa to M. incognita and M. javanica populations. Potato cultivars Sifra, Lanorma, Innovator, Uptodate and FL2108.2006.1 were each inoculated with 5000 eggs and second-stage juveniles (J2) in separate trials over two seasons. Fifty-six days after inoculation, the reproductive potential (RP = eggs and J2/g roots) of nematodes on each cultivar was assessed. In M. incognita, RP values ranged from 79.28 to 197.11 in Experiment 1 and from 47.31 to 1327 in Experiment 2 on potato cultivars. Similarly, in M. javanica trial, RP values ranged from 6.13 to 327.02 and from 16.88 to 237.42 in the respective experiments. In conclusion, all tested high yielding commercial potato cultivars in South Africa were excellent hosts to M. incognita and M. javanica population.