Robusta coffee rootstocks resistants to Meloidogyne paranaensis and M. incognita races 1 and 2

Abstract

The Meloidogyne paranaensis and M. incognita races 1 and 2 are the most pathogenic root knot nematodes of coffee crop in Paraná state, Brazil. The use of susceptible arabica cultivars on resistant rootstock robusta cultivars, especially cultivar Apoatã IAC-2258 of Coffea canephora var. robusta, has been successful, but there are segregations to susceptible ones. The aim of this research was to identify C. canephora var. robusta coffee trees with simultaneous resistance to M. paranaensis, M. incognita races 1 and 2. Twenty-four C. canephora genotypes were evaluated using Taylor´s evaluation method, conducted in randomized blocks design with three replications and 30 plants per plot. The cultivar Mundo Novo IAC 376-4 was used as susceptible standard. The variables evaluated were nematodes incidence and root volume. The resistance levels founded among plants were resistant, moderately resistant and susceptible. Six genotypes of C. canephora var. robusta with simultaneous resistance, probably in homozygous, to M. paranaensis, M. incognita race 1 and M. incognita race 2 were found, all with good root volume. The mother plants of these six better treatments will be vegetatively propagated and used to begin seed production of rootstock cultivars.