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An entomopathogenic nematode, Steinernema citrae- Nematode Information

Galleria-baiting technique (Bedding and Akhurst, 1975), was used to isolate an entomopathogenic nematode from the soil collected from a citrus orchard in South Africa. Based on molecular characteristics, this new nematode was named as Steinernema citrae that  found to be closely related Stienernema feltiae group.

For detail information read following original paper

Bedding, R.A. and R.J. Akhurst. 1975. A simple technique for detection of insect parasitic rhabditid nematodes in soil. Nematologica. 21: 109-110.

Stokwe, N.F., Malan, A.P., Nguyen, K.B., Knoetze, R. and Tiedt, L. 2011. Steinernema citrae n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from South Africa. Nematology 13: 569-587.

An entomopathogenic nematode, Heterorhabditis atacamensis- Nematode Information

New entomopathogenic nematode species was found in the soil collected from Atacama Desert in Chile and was named after Atacama Desert as Heterorhabditis atacamensis. I like the way nematode taxonomists (Edgington et al., 2011) used individual morphological characteristics to differentiate this new species from other morphologically similar species of entomopathogenic nematodes. For example, these researchers showed that the H. atacamensis differed from H. marelatus, H. downesi and H. amazonensis based on position of hemizonid (a nematode sensory organ), position of excretory pore and female tail terminus shape, and number and position of genital papillae, respectively.  Using molecular techniques, Edgington et al. (2011) were also able to distinguish H. atacamensis from closely related entomopathogenic nematode species, H. safricana.

 Research Paper

Edgington, S., Buddie, A. G., Moore, D., France, A., Merino, L. and Hunt, D. J. 2011. Heterorhabditis atacamensis n. sp (Nematoda: Heterorhabditidae), a new entomopathogenic nematode from the Atacama Desert, Chile. Journal of Helminthology 85: 381-394.

New entomopathogenic nematode, Oscheius carolinensis- Nematode Information

Based on morphological and molecular characteristics, the nematode isolated from vermicompost using Galleria bait method (Bedding and Akhurst, 1975) has been described as a new entomopathogenic nematode species, Oscheius carolinensis (Ye et al., 2010).  This nematode is also pathogenic to cabbage butterfly (Pieris rapae) and mealworms (Tenebrio molitor).

 Literature

Bedding, R.A. and R.J. Akhurst. 1975. A simple technique for detection of insect parasitic rhabditid nematodes in soil. Nematologica. 21: 109-110.

Ye, W., Torres-Barragan, A. and Cardoza, Y.J. 2010. Oscheius carolinensis n. sp. (Nematoda: Rhabditidae), a potential entomopathogenic nematode from vermicompost. Nematology 12: 121-135.

Entomopathogenic nematodes from Egypt

The occurrence and distribution of entomopathogenic nematodes including Heterorhabditis indica, Steinernema abbasi and Steinernema carpocapsae have been reported from four geographical regions (Northern, Middle, Southern and Sinai Peninsula) of Egypt.

These findings were presented by Abu-Shady, N.M., Shamseldean, M.M., Abd-Elbary, N.A. and Stock, S.P. at the 50th annual meeting of the Society of Nematologists held in Corvallis, Oregon from July 17-20, 2011.

• A presence of entomopathogenic nematode species including Steinernema khoisanae, Steinernema yirgalemense, Steinernema citrae, Heterorhabditis bacteriophora and Heterorhabditis zealandica have been reported in citrus orchards in the Western Cape, Eastern Cape and Mpumalanga provinces of South Africa (Malan et al., 2011).
• All the above nematode species have showed a very high virulence against false codling moth, Thaumatotibia leucotreta an economically important pest of citrus in South Africa.  For example, S. yirgalemense can cause over 74% mortality of both larval and pupal mortality of false codling moth when applied at the rate of 50-200 infective juveniles/ larval or pupal stages of false codling moth.
• Two entomopathogenic nematode species including S. yirgalemense and S. citrae were reported for the first time from South Africa (Malan et al., 2011).

Read following papers on entomopathogenic nematodes from South Africa

de Waal, J.Y., Malan, A.P. and Addison, M.F. 2011.  Evaluating mulches together with Heterorhabditis zealandica (Rhabditida: Heterorhabditidae) for the control of diapausing codling moth larvae, Cydia pomonella (L.) (Lepidoptera: Tortricidae).  Biocontrol Science and Technology 21: 255-270.

de Waal, J.Y., Malan, A.P., Levings, J. and Addison, M.F. 2010.  Key elements in the successful control of diapausing codling moth, Cydia pomonella (Lepidoptera: Tortricidae) in wooden fruit bins with a South African isolate of Heterorhabditis zealandica (Rhabditida: Heterorhabditidae). Biocontrol Science and Technology. 20: 489-502.

Hatting, J., Stock, S.P. and Hazir, S.  2009. Diversity and distribution of entomopathogenic nematodes (Steinernematidae, Heterorhabditidae) in South Africa.  Journal of Invertebrate Pathology 102: 120-128.

Malan, A.P., Knoetze, R. and Moore, S.D.  2011.  Isolation and identification of entomopathogenic nematodes from citrus orchards in South Africa and their biocontrol potential against false codling moth. Journal of Invertebrate Pathology 108: 115-125.

Malan, A.P., Nguyen, K. B. and Addison, M. F. 2006.  Entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) from the southwestern parts of South Africa. African Plant Protection 12: 65-69.

Malan, A.P., Nguyen, K.B., de Waal, J.Y. and Tiedt, L. 2008. Heterorhabditis safricana n. sp (Rhabditida : Heterorhabditidae), a new entomopathogenic nematode from South Africa. Nematology 10: 381-396.

Entomopathogenic nematodes and qPCR

Quantitative real-time PCR (qPCR) technique can be used for the identification of entomopathogenic nematodes in the both Heterorhabditidae and Steinernematodae families directly from soil samples.

Species specific primers and TaqMan (R) probes from the ITS rDNA region for the EPNs were used for the identification of four species of entomopathogenic nematodes including Heterorhabditis bacteriophora, Steinernema carpocapsae, Steinernema feltiae and Steinernema scapterisci (Campos-Herrera et al., 2011).

A publication on indentification of entomopathogenic nematodes using quantitative real-time PCR (qPCR) technique.

Campos-Herrera, R., El-Borai, F.E., Stuart, R.J., Graham, J.H. and Duncan, L.W. 2011.   Entomopathogenic nematodes, phoretic Paenibacillus spp., and the use of real time quantitative PCR to explore soil food webs in Florida citrus groves. Journal of Invertebrate Pathology 108: 30-39.