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Xenocriconemella (De Grisse and Loof, 1965)
Criconemella (De Grisse and Loof, 1965)
Madinema (Khan, Chawla and Saha, 1976)
Seshadriella (Darekar and Khan, 1981)
Neobakernema (Ebsary, 1981)
Crossonemoides (Eroshenko, 1981)
Macroposthonia (de Man, 1921)
Criconemoides is an agriculturally-important genus that has undergone several name changes over the years. Fortunately, the species names have remained stable. A considerable amount of the earlier literature on nematodes in the genus Criconemoides (Family: Criconematidae) refers to them by generic names that have since been synonymized, particularly Criconemoides, Macroposthonia and Criconemella. Maggenti (personal communication) argued to suppress the generic name Criconemella and to resurrect Criconemoides. That resurrection was accepted by some authors (Al Banna and Gardner, 1993), but more recently Luc proposed the name Criconemoides, which has gained fairly wide acceptance (e.g. Pinkerton et al., 1999; Carneiro et al., 1998).
A very large number of species has been described within the genus Criconemoides sensu lato. The genus was erected by Taylor (1936) to accommodate Criconematidae without cuticular extensions of the annules. When new genera were erected, the original name, Criconemoides, remained in question due to incomplete original description and lack of availability of type material. Subsequently, Criconemella was used but because there was no formal diagnosis of that genus, Brzeski et al. (2002a) resurrected the genus name Criconemoides. The name Criconemoides was proposed by Andrássy (1965) for species within Criconemoides with crenated margins of the annules. Through some convoluted history of generic name changes, well documented by Brzeski et al. (2002b), Criconemoides was resurrected as a genus name by Loof and de Grisse, 1989).
Ring nematodes derive their name from their cuticle which is deeply
striated. The thickness of the cuticle may make it difficult to observe
Female: Body of variable length (0.20 to 1.00 mm); heavy annulation of cuticle - 200 or fewer, no spines, no extra cuticle; posterior edge smooth. Submedian lobes generally well-developed, but may be poorly developed and even absent in some species; separated or connected in different ways; first annules may be reduced or even divided into plates.
Vulval lips closely appressed (vulva "closed")
Females have long stylet and anchor-shaped knobs.
have no stylet or bursa; have straight spicule.
Head end rounded to conoid; generally four lateral lines, rarely three, caudal alae distinct, exceptionally absent (C. goodeyi).
Juveniles: Annuli smooth.
[Ref: Raski & Luc, Rev. Nematol. 10(4):409-444 (1987), and H. Ferris.]
Ring Nematode movement. Video Source: J.D. Eisenback, Nemapix.
Specimens of this interesting group of nematodes were rarely detected in soil samples, and were usually in low numbers, until the development of sugar flotation and centrifugation extraction techniques (Jenkins, 1964). Those techniques maximize recovery of "wide-bodied", slow-moving nematodes. They revealed that ring nematodes are very common, particularly in permanent crop, landscape and ornamental plantings. They can also be very abundant. Population levels of 50,000/l of soil have been recovered from around roots of peach trees (Jaffee and McInnis, 1991). Usually, diagnostic assessments of ring nematodes in soil samples are made only to the genus level. There may be several species associated with cultivated grapevines.
D-rated pests in California.
Ring nematodes feed ectoparasitically on root tips or along more mature roots. The nematodes are migratory unless soil pore space limits their movement. Adult stages of the larger ring nematode adults appear sedentary or stuck within their pore space as they develop to adult size.
Woody plants and turf are hosts for many species.
For an extensive list of host plant species and their susceptibility to this genus, copy the genus name
select Nemabase Genus Search and paste the name in the Genus box
Nematodes exhibit characteristic slow, sluggish movement.
This group of nematodes is relatively unstudied on grape, however, among Prunus spp. it is known to seriously alter host physiology (Nyczespir and Wood, 1988).
Extraction poor except with sugar/centrifuge - then found frequently.
Pinkerton, J. N.; Forge, T. A.; Ivors, K. L.; Ingham, R. E.. 1999. Plant-parasitic nematodes associated with grapevines, Vitis vinifera, in Oregon vineyards. Journal of Nematology, 31:624-634.
Carneiro, Regina M.D.G.; Carvalho, Flavio L.C.; Kulczynski, Stela Maris. 1998. Plant selection to control Criconemoides xenoplax and Meloidogyne spp. with crop rotation. Nematologia Brasileira, 22:41-48.
Raski & Luc, Rev. Nematol. 10:409-444 (1987)
Brzeski, M., Y.E. Choi and P.A.A. Loof. 2002a. Compendium of the genus Criconemoides Taylor, 1936 (Nematoda: Criconematidae). Nematology 4:325-339.
Brzeski, M., P.A.A. Loof and Y.E. Choi . 2002b. Compendium of the genus Criconemoides Andrássy, 1965 (Nematoda: Criconematidae). Nematology 4:341-360.
Loof, P.A.A and A. De Grisse. 1989. Taxonomic and nomenclatorial observations on the genus Criconemella De Grisse and Loof, 1965 sensu Luc and Raski, 1981. Med. Fac. Landn. Rijksuniv. Gent. 54:53-74.