Last year a new species of entomopathogenic nematode was isolated by Nguyen and Buss (2011) from a white grub (Phyllophaga sp.) and based on morphological and molecular characteristics, it was named as Steinernema phyllophagae.
Nguyen, K.B., and Buss, E.A. 2011. Steinernema phyllophagae n. sp (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Florida, USA. Nematology 13: 425-442.
Strawberry crown moth and entomopathogenic nematodes- Nematode information In a laboratory assay, when entomopathogenic nematodes including Steinernema carpocapsae and Heterorhabditis bacteriophora are in direct contact, the can cause over 94% mortality of strawberry crown moth (Synanthedon bibionipennis) larvae but when applied in the field, these nematodes are not in direct contact with insects therefore, they can cause up to 51% insect mortality (Bruck et al., 2008).
Bruck, D.J., Edwards, D.L. and Donahue, K.M. 2008. Susceptibility of the strawberry crown moth (Lepidoptera : Sesiidae) to entomopathogenic nematodes. Journal of Economic Entomology 101: 251-255.
Efficacy of entomopathogenic nematodes against white grub, Holotrichia longipennis Today, I read a paper published in Journal of Pest Science by Khatri-Chhetri et al. (2011), who tested the efficacy of two newly isolated entomopathogenic nematode species from Nepal against white grub, Holotrichia longipennis. This white grub is a very serious pest of many crops including black gram, cabbage, chilies, maize, millet, paddy soybean and tomato.
Read MoreAn 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 Nematode Virulence- Nematode information It is well known fact that the infective juveniles of both Steinernema spp. and Heterorhabditis spp. enter their insect host through natural openings such as mouth, anus and spiracles and eventually reach in the insect body cavity. As insects do not have a closed circulatory system like animals, their body cavity acts as an open circulatory system, which is filled with the blood that is technically called as hemolymph.
Read MoreEntomopathogenic nematodes and Wireworms, Agriotes lineatus- Nematode Information Wireworm, Agriotes lineatus cause a tremendous loss to potato yields throughout the world. As biological control agent, entomopathogenic nematodes can serve as a safe alternative to chemical pesticides in managing wireworms and helping to increase potato yields. It has been shown that the entomopathogenic nematode, Heterorhabditis bacteriophora can cause over 67% mortality of wireworm, Agriotes lineatus within three weeks of application (Ansari et al., 2009).
Literature
Ansari, M.A., Evans, M. and Butt, T.M. 2009. Identification of pathogenic strains of entomopathogenic nematodes and fungi for wireworm control. Crop Protection 28: 269-272.
Entomopathogenic nematodes and the sugarcane billbug, Sphenophorus levis- Nematode Information Sugarcane is grown as an important cash crop in many countries but insect pests like the sugarcane billbug, Sphenophorus levis can cause a tremendous yield loss to this crop. Entomopathogenic nematodes have a great potential to use as a biological control agent against the sugarcane bill bugs. Recently, Giometti et al. (2011) reported that entomopathogenic nematodes including Steinernema brazilense strain IBCB n6 and three strains of Heterorhabditis sp. (IBCB n10, IBCB n24 and IBCB n44) were highly virulent causing over 60% mortality of adults of the sugarcane billbug. Sphenophorus levis.
Publications:
Giometti, FHC, Leite, LG., Tavares, FM., Schmit, F.S., Batista, A. and Dell'Acqua, R. 2011. Virulence of entomopathogenic nematodes (Nematoda: Rhabditida) against Sphenophorus levis (Coleoptera: Curculionidae). Bragantia 70: 81-86.
Entomopathogenic nematodes- Mode of Infection In the soil environment, infective juveniles of entomopathogenic nematodes (Figure 1.) are always searching for the insect hosts to infect, kill, feed and reproduce. Once the infective juveniles of both Steinernematid (Steinernema spp.) and Heterorhabditid (Heterorhabditis spp.) nematodes locate any larval, pupal or adult stages of their insect host, they will rush to find any easy entry routes/points to enter into the insect host body.
Read MoreEntomopathogenic Nematodes- Nematode Information Insect-parasitic nematodes that belong to both Steinernematidae and Heterorhabditidae families are also called as entomopathogenic nematodes because they cause disease to their insect hosts with the help of mutualistically associated symbiotic bacterial pathogens.
Read MoreStored grain/ product pests: Nematode Information Several stored grain/product insect pests like Indian meal moth (Plodia interpunctella), Mediterranean flour moth (Ephestia kuehniella), Sawtoothed grain beetle (Oryzaephilus surinamensis), Mealworms (Tenebrio molitor), Red flour beetle (Tribolium castaneum) and Warehouse beetle (Trogoderma variabile) attack and destroy large quantities of stored grains and products during long-term storage in farm bins, grain processing facilities, warehouses, retail stores, and eventually also on the consumer shelves.
Read MoreEntomopathogenic nematodes and their symbiotic bacteria- Nematode Information
Molecular studies demonstrated that the closely related Photorhabdus, symbiotic bacteria of Heterorhabditis nematodes and Xenorhabdus, symbiotic bacteria of Steinernematid nematodes have developed totally different molecular strategies for the same objective of virulence to insects and symbiosis with the nematode.
These findings were presented by An, R. and Grewal, P.S. at the 50th annual meeting of the Society of Nematologists held in Corvallis, Oregon from July 17-20, 2011.
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 warm-adapted entomopathogenic nematode Steinernema siamkayai Tiruchirappalli strain can cause 45-100% larval mortality of various insect species including Galleria mellonella, Spodoptera exigua, Ceratitis capitata, Cydia splendana and Tenebrio molitor when tested under laboratory conditions at temperatures between 15- 37C (Raja et al., 2011).
Read MoreAn entomopathogenic nematode from Thailand:Nematode Information Based on the morphological and molecular studies, entomopathogenic nematode, Steinernema siamkayai was reported as a new species from Thailand in 1998.
Publication:
Entomopathogenic nematodes and Colorado potato beetle
Publications:
Entomopathogenic nematodes and False codling moth
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.
It has been demonstrated that the curative applications of the entomopathogenic nematode Steinernema carpocapsae in a chitosan formulation can reduce the population of red palm weevil, Rhynchophorus ferrugineus infesting Cretan Date Palm, Phoenix theophrasti (Dembilio et al., 2011). Read following papers for more information.
Dembilio, O., Karamaouna, F., Kontodimas, D. C., Nomikou, M. and Jacas, J. A. 2011. Short communication. Susceptibility of Phoenix theophrasti (Palmae: Coryphoideae) to Rhynchophorus ferrugineus (Coleoptera: Curculionidae) and its control using Steinernema carpocapsae in a chitosan formulation. Spanish Journal of Agricultural Research 9: 623-626.
Dembilio, O., Llacer, E., de Altube, M.D.M. and Jacas, J.A. 2010. Field efficacy of imidacloprid and Steinernema carpocapsae in a chitosan formulation against the red palm weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Phoenix. Pest Management Science 66: 365-370.