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Aphelenchoides besseyi (a foliar nematode) infecting the foliar tissues of Lantana sp.
Photograph courtesy of Jason D. Stanley, DPI

Aphelenchoides besseyi (a foliar nematode) infecting Lantana sp.
Note the dark necrotic leaf spots induced by nematode feeding and migration. The adjacent healthy green leaf tissue escaped the nematode colonization.
Photograph courtesy of Jason D. Stanley, DPI

Cucurbita moschata ‘La Estrella’ (tropical pumpkin) with root system heavily galled due to the infection induced by Meloidogyne javanica and Meloidogyne mayaguesis.
Photograph courtesy of Mariana P. Beckman and Janete A. Brito, DPI

Nematology Section

Compiled by Jason D. Stanley, M.S., Renato N. Inserra, Ph.D., Maria de Lourdes Mendes, Ph.D., and Janete A. Brito, Ph.D.

This section analyzes soil and plant samples for nematodes, conducts pest detection surveys and provides diagnosis of plant problems, in addition to completing identification of plant parasitic nematodes involved in regulatory and certification programs. State of Florida statutes and rules mandate the principal part of the regulatory activity of the section. Analyses of plant and soil samples include those from in-state programs, plant shipments originating in Florida destined for other states and countries, as well as samples intercepted in Florida from outside the United States.

Nematodes of Special Interest

In Florida, foliar nematodes belonging to the genus Aphelenchoides can be found parasitizing both ornamental and horticultural crops. The most economically important species in this genus are A. besseyi, A. fragariae and A. ritzemabosi. Ornamentals infected by these nematodes are unmarketable due to leaf damage and eventual defoliation. Plant symptoms include necrosis, chlorosis, discoloration and distortion of leaf tissues. The likelihood of infection by these nematodes is increased by high humidity and water droplets on foliage. These conditions facilitate nematode movement from the soil to the leaves and subsequent penetration of leaf tissues. Cultural practices that reduce excess moisture on plant foliage may help prevent infection and movement of these foliar nematodes. These practices include providing sufficient ventilation, avoiding overhead irrigation, using clean plant stock and maintaining rigorous sanitation.

Aphelenchoides besseyi Christie, 1942, a foliar nematode, was found infecting the leaves of a Lantana sp., an ornamental plant. (Manatee County; N09-1314, James E. “Eddie” Anderson, 2 November 2009.)

Meloidogyne javanica (Treub, 1885) Chitwood, 1949, the Javanese root-knot nematode, was found infecting the roots of Cucurbita moschata ‘La Estrella,’ a tropical pumpkin. (Manatee County, N09-01388, Karen L. Etchells, 23 November 2009.)

Meloidogyne mayaguensis Rammah & Hirschmann, 1988, the guava root-knot nematode, a new County record, was also found infecting the root system of Cucurbita moschata ‘La Estrella.’ This nematode species induces severe root galling in many crops, including cucurbits. Several plant species have been found to be good hosts for this root-knot nematode species in Florida. (Manatee County, N09-01388, Karen L. Etchells, 23 November 2009.)

Collectors submitting five or more samples that were processed for nematological analysis in November - December 2009