TABLE CONTENTS

Meloidogyne mayaguensis and M. ethiopica, the Major Root-knot
Nematodes Parasitizing Guava and Grapevine in Central and South
America
Carneiro, R.M.D.G. (1), , C.B.G. Gomes (2) & R.G. Carneiro
(1) Embrapa - Recursos Genéticos e Biotecnologia, C.P. 02372, 70849-979 Brasilia, DF, Brazil; (2) Embrapa
Clima Temperado, C.P.403, 96001-970 - Pelotas-RS; (3) Instituto Agronômico do Paraná-IAPAR,
C.P. 481, 860001-970 Londrina, PR.
The worst nematode problem affecting guava is that created by Meloidogyne spp., which
recognized AS A limiting factor in commercial guava production in Central and South
America. Considering the difficulty of identifying Meloidogyne mayaguensis only by the
perineal pattern, this species has been misidentified in different regions around the world.
Severely infected trees are associated with general chlorosis, nutrient deficiency symptoms
increase rapidly, reduced flowering and fruiting, culminating in the death of the plants. This
nematode is making cultivation of guava in the infested areas unfeasible, causing serious
economic problems to growers and the economy of the region. Recently, a survey made in
Chile using esterase isozyme indicated the wide distribution of M. ethiopica in about 80 % of
samples on grapevine, kiwi and tomato. The nematode occurred over a range of 1,000 Km,
including all nurseries sampled. Contaminated nurseries have resulted in serious infestation
by M. ethiopica in vineyards in various places in Chile and the introduction of this nematode
in Rio Grande do Sul State, Brazil on kiwi seedlings. M. ethiopica is a highly aggressive
species in these more sensitive grape varieties (Chardonnay, Sauvignon Blanc and Pinot)
causing significant mortality rates, or in the best of cases, rendering its host plant virtually
non-productive. In this presentation we will focus on distribution, hosts, damage, source of
resistance and antagonistic plants to be used in management strategies to control these two
nematodes.
5 th International Congress of Nematology, 2008 157