Major tolerance in fringed looseleaf cultivars was also observed by GOMES (1996) and MENDES (1998).
Other studies (MALUF et al., 2003; WILCKEN et al., 2005) reported that 'Salinas 88', a USDA crisphead cultivar,presents resistance to M. incognita as well as to M. javanica. Nematode resistance in smooth leaved (butterleaf) types has not yet been reported.