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Cactodera torreyanae Cid del PradoVera & Subbotin, 2014
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:
Dsecribed from saline soil on the campus of the Colegio de Postgraduados,
Nurse cell system: A multinucleate syncytium.
A. Female body on outside of roots, with eggs retined.
C. Dissolution of cell walls during mycalium formation
E. Syncytium (S) obstructing phloem tissue (P). C = root
cortex, E= root epidermis
Photomicrographs from Evans et al (2015)
Suaeda edulis. The type host was originally lited as S.
torreyana but then described as a new species, S. edulis.
The female body remains on the outside of the root and forms a cyst in which
the eggs are retained. During the life cycle, none of the post-embryonic stages
completely penetrate the host roots, so Evans et al. (2015) considered C.
torreyanae to be a sedentary ectoparasite. Alternatively, it could be
described as a sedentary semiendoparasite.
Males emerge from the fourt stage cuticle and return to the soil.
Although the female exudes a gelatioous matrix, no eggs were obeserved in it.
However, males were observed trapped in the matrix which led to the hypothesis
that the matrix may contain pheromones and that reproduction is sexual (Evans et
Photomicrographs of semiendoparasitic (ectoparasitic)
location of all life stages (A: J2; B: J3; C::J4 female; D: J4 male; E and F:
(from Evans et al., 2015).
Although females produce a gelatinous mass, all eggs
seem to be retained in the cyst. It is possible that the gelatinous
mass contains a slow-release pheromone which acts as a sex attractant (Cid
del Prado, pers. comm.).
Cactodera torreyanae female on root surface
with associated gelatinous mass (Photograph by I. Cid del Prado).
Disruption of phloem tissues.
Host Plant Resistance, Non-hosts and Crop Rotation alternatives:
Cid del Prado Vera, I., and S. A. Subbotin 2014. new cyst
nematode, Cactodera torreyanae sp. n. (Tylenchida: Heteroderidae), parasitising
romerito, Suaeda torreyana, in Texcoco, Mexico. Nematology 16:163-174.
Evans, G., I Cid del Prado Vera, P Yanez-Jimenez, R
Noguez-Hernandez. 2015. LIFE CYCLE OF THE CYST FORMING NEMATODE CACTODERA
TORREYA CID DEL PRADO AND SUBBOTIN, 2014 AND ITS RELATIONSHIP WITH ITS HOST
SUAEDA EDULIS FLORES OLV. & NOGUEZ. Nematropica 45:189-197.