Meloidodera floridensis

Meloidodera floridensis	Contents	Rev 09/23/2023
Pine Cystoid Nematode	Classification	Hosts
	Morphology and Anatomy	Life Cycle
Return to Meloidodera Menu	Economic Importance	Damage
	Distribution	Management
Return to Heteroderidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

      Tylenchida
       Tylenchina
        Tylenchoidea
         Heteroderidae
          Meloidoderinae

Meloidodera floridensis Chitwood, Hannon & Esser, 1956

Type species of the genus.

Synonyms:
None.

Morphology and Anatomy:

Females:

Female does not form a cyst..
Body globose, spherical to pear-shaped with short neck and no terminal cone.
Head with 3 to 4 annules; labial disc elongate
Excretoy pore at base of neck region,
Vulva equatorial, at mid-body, not terminal;
Anus and vulva more separated than in Meloidogyne
Eggs are retained in female body.

Ref: Chitwood et al., 1956; Baldwin, 1992, Hopper, 1960

Second-stage juveniles:

Phasmids lens-like

Males:

Not foundi in original material used for species description.
Usually rare
Lips and head annules fused togther

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Distribution:

Described by Chitwood et al. (1956) from roots of Pinus ellingtonii from Olustee, Florida, USA. Also reported throughout the southeaqstern USA on pine as the host.

The nurse cell system is a uninucleate giant cell, usually in the pericycle. The nucleus is irregularly hypertrophied nucleus and has a variable number of nucleoli. Hyperplasia occurs in cells adjacent to the giamt cell. The giant cell has direct contact with the vascular system. Plasmodesmata are concentrated in pit fields adjacent to the vascular parenchyma, facilitating access to nutrients (Palomares-Rius et al., 2017; Mundo-Ocampo and Baldwin, 1983). .

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Hosts:

For an extensive host range list for this species, click

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Life Cycle:

Triantaphyllou (1971) and Triantaphyllou and Hirschmann (1973) described M. floridebsis as a triploid, thelytokous parthenogenetic organism. Males are generally rare in natural populations infecting pine roots. The triploid condition is probably maintained byreproduction throuhj nitotic partyhenogeneis. At least 96% of the second-stage juveniles that entered and fed in pine roots developed into adult females. The remaining 4% apparently failed to establish feeding sites in the host and developed into very small males. However, when juveniles were subjected to prolonged periods of starvation in water, more than 50% became males after entering pine roots while the remainder did not reach maturity. They concluded that to a large extent, that sex determination in M. floridenisis is determined by environmental conditions. One might speculate that the starvation stress on the juveniles reduced their ability to induce giant cells of dufficient quality to support development into females.

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters

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Damage:

Pine cystoid nematode was ahown to cause considerable root damage to lonlolly pine (Pinus taeda) and slash pine (P. caribaea) but did not stunt the plants as much as lance nematode (Hoplolaimus coronatus) (Ruehle and Sasser, 1962).

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Management:

Host Plant Resistance, Non-hosts and Crop Rotation alternatives:

For plants reported to have some level of resistance to this species, click

Manipulated sex determination:

In the Heteroderidae, the possibility of manipulating sex ratios by environmental modification or chemical stresses is intriguing although it has not been vigorously pusued. Since males do not produce eggs, increase in the ratio of males to females should reduce the rate of population increase and consequently the damage to plant hosts.

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References:

Baldwin, J.G.1992. Evolution of cysta and noncyst-forming Heteroderinae. Annual Review of Phytopathology 30:271-290.

Chitwood, B.G., Hannon, C.I., Esser, R.P. 1956, A new nematode genus, Meloidodera, linking the genera Heterodera and Meloidogyne. Phytopathology 46:264-266.

Ghaderi, R. 2019. Systematics of cystoid nematodes. Riga, Latvia, Scholars Press.

Ghaderi, R. 2019. An outline on distribution and hosts of the cystoid nematodes of Ataloderinae Wouts, 1973 and Meloidoderinae Golden, 1971. Zootaxa 4664: 339-350 https://www.mapress.com/j/zt/

Mundo-Ocampo, M., Baldwin, J. G. 1983. Host response to Meloidodera spp. (Heteroderidae). J. Nematol. 15:544-554.

Palomares-Rius, J.E., Escobar, C., Cabrera, J., Vovlas, A., Castillo, P. 2017. Anatomical altertions in plant tissues induced by plant-parasitic nematodes. Frontiers in Plant Sciencew Sec. Plant Pathogen Interactions, 8:| https://doi.org/10.3389/fpls.2017.01987

Ruehle, J.L., Sasser, J.N. 1962. The role of plant-parsitic nematodes in stunting of pines in southern plantations. Plant Disease Reporter 52:56-68.

Subbotin, S.A., Akanwari, J., Nguyen, C.N., Cid del Prado Vera, I., Chitambar, J.J., Inserra, R.N. & Chizhov, V.N. 2017. Molecular characterization and phylogenetic relationships of cystoid nematodes of the family Heteroderidae (Nematoda: Tylenchida). Nematology 19: 1065-1081.

Triantaphyllou, A. C. 1971. Oogenesis and the chromosomes of the cystoid nematode, Meloidodera floridenis. J. Nematol. 3: 1 83-88.

Triantaphyllou, A.C. 1973. Environmental sex determination of nematodes in relation to pest management. Annual Reiew of Phytopathology 11:441-462

TriantaphylIou, A. C., Hirschmann, H. 1973. Environmentally controlled sex expression in Meloidodera floridensis. J. Nematol. 5:181-185.