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Presence of entomopathogenic nematode, Heterorhabditis megidis have been reported for the first time in the soil samples collected form Eastern Black Sea region of Turkey.  Nematodes were isolated using Galleria-baiting technique (Bedding and Akhurst, 1975) and identified using classical morphological (Poinar et al. 1987) and molecular techniques (Yilmaz et al., 2009).

Read following literature for more information

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

Poinar, G. O., Jr., T. Jackson, and M. Klein. 1987. Heterorhabditis megidis sp. n. (Heterorhabditidae: Rhabditida) parasitic in the Japanese beetle,Popillia japonica (Scarabaeidae: Coleoptera), in Ohio. Proceedings of the Helminthological Society of Washington 54:53-59.

Yilmaz, H., Waeyenberge, L., Demir, I., Moens, M., Demirbağ, Z. 2009. A new entomopathogenic nematode species for Turkey, Heterorhabditis megidis Poinar, Jackson & Klein 1987 (Rhabditida: Heterorhabditidae). Turkish Journal of Agriculture and Forestry. 33: 385-391.

• The leaf beetles, Altica quercetorum and Agelastica alni are serious pests of urban trees including Quercus sp and Alnus sp, respectively.
• The elm leaf beetle Xanthogaleruka luteola is a serious pest that causes defoliation of eml trees (Ulmus spp.) in North America.
• Adults of these beetles generally feed on leaves by chewing holes through the leaf tissue.
• Larvae skelotonize leaves by feeding on leaf tissues leaving veins and upper epidermis intact.
• Entomopathogenice nematodes including Heterorhabditis megidis, Steinernema carpocapsae and S. feltiae can be used as potential biocontrol agents against different species leaf beetles (read Grewal et al., 2005 for more information).
• It has been shown that both the pre-pupal and pupal stages of A. quercetorum and A. alni are very susceptible to H. megidis when applied in the soil.
• The last instar larvae of X. luteola are highle susceptible to S. carpocapsae when applied to the mulch.

How Entomopathogenic Nematodes kill leaf beetles

• When the infective juveniles are applied to the soil surface or mulch, they start searching for their hosts, in this case leaf beetles grubs.
• Once a beetle grub has been located, the nematode infective juveniles penetrate into the grub body cavity via natural openings such as mouth, anus and spiracles.
• Infective juveniles of Heterorhabditis also enter through the intersegmental members of the grub cuticle.
• Once in the body cavity, infective juveniles release symbiotic bacteria (Xenorhabdus spp. for Steinernematidae and Photorhabdus spp. for Heterorhabditidae) from their gut in grub blood.
• In the blood, multiplying nematode-bacterium complex causes septicemia and kills grubs usually within 48 h after infection.
• Nematodes feed on multiplying bacteria, mature into adults, reproduce and then emerge as infective juveniles from the cadaver to seek new larvae in the soil.

References: Refer following book to read more about efficacy of entomopathogenic nematodes against leaf beetles

1. Grewal, P.S. Ehlers, R.-U., Shapiro-Ilan, D. (eds.). Nematodes As Biocontrol Agents. CAB publishing, CAB International, Oxon

Infective juveniles of entomopathogenic nematodes use three different strategies to find their insect hosts.
1. Ambush foraging: Ambushers such as Steinernema carpocapsae and S. scapterisci have adapted “sit and wait” strategy to attack highly mobile insects (billbugs, sod webworms, cutworms, mole-crickets and armyworms) when they come in contact at the surface of the soil.  These nematodes do not respond to host released cues but infective juveniles of some Steinernema spp can stand on their tails (nictate) and easily infect passing insect hosts by jumping on them.  Since highly mobile insects live in the upper soil or thatch layer, ambushers are generally effective in infecting more insects on the surface than deep in the soil.
2. Cruise foraging: Cruiser nematodes such as Heterorhabditis bacteriophora, H. megidis, Steinernema glaseri and S. kraussei generally move actively in search of hosts and therefore, they are distributed throughout the soil profile and more effective against less mobile hosts such as white grubs and black vine weevils.  Cruisers never nictate but respond to carbon dioxide released by insects as cues.
3. Intermediate foraging: Some nematode species such as Steinernema feltiae and S.riobrave have adapted a strategy in between ambush and cruise strategies called an intermediate strategy to attack both the mobile and sedentary/less mobile insects at the surface or deep in the soil.  Steinernema feltiae is highly effective against fungus gnats and mushroom flies whereas S.riobrave is effective against corn earworms, citrus root weevils and mole crickets.

• The shore fly, Scatella stagnalis (Fallén) (Diptera: Ephydridae) is an important insect pest of greenhouse plants.
• Larvae of these flies mainly feed on blue-green algae grown on the surface of plant growing media, walls, floors, benches, and pots.
• But larvae can also cause a serious damage to tender plant tissues thus reducing quality and productivity of plants.
• The adults are not considered as plant feeders but they are nuisance to people and disseminate pathogens such as Fusarium and Pythium from plant to plant as they disperse through the greenhouse.
• Currently, most growers rely on chemicals that kill host plants such as blue-green algae to reduce the incidence of shore flies. However, this method has not been proved effective in reducing shore fly incidence.
• Biological control agents including Bacillus thuringiensis var. thuringiensis (Bt) and entomopathogenic nematodes have been considered as alternatives to chemical pesticides.
• For successful control of shore flies, entomopathogenic nematodes can be easily applied in water suspension as spray application to the surface of plant growing medium.
• Entomopathogenice nematodes including Heterorhabditis megidis, Steinernema arenarium and Steinernema feltiae when applied at the rate of 50 nematodes/cm2 can cause 94- 100% mortality of shore flies.

How Entomopathogenic Nematodes kill Shore flies

• When the infective juveniles are applied to the surface of plant growing substrate, they start searching for their hosts, in this case shore fly larvae.
• Once a larva has been located, the nematode infective juveniles penetrate into the larval body cavity via natural openings such as mouth, anus and spiracles.
• Infective juveniles of Heterorhabditis spp also enter through the intersegmental members of the larval cuticle.
• Once in the body cavity, infective juveniles release symbiotic bacteria (Xenorhabdus spp. for Steinernematidae and Photorhabdus spp. for Heterorhabditidae) from their gut in the larval blood.
• In the blood, multiplying nematode-bacterium complex causes septicemia and kills shore fly larvae usually within 48 h after infection.
• Nematodes feed on multiplying bacteria, mature into adults, reproduce and then emerge as infective juveniles from the cadaver to seek new larvae in the potting medium/soil.

For more information on the interaction between entomopathogenic nematodes and leafminers, please read following research and extension publications.

• Foote, B.A. 1977.  Utilization of blue-breen algae by larvae of shore flies. Environmental Entomology 6, 812-814.
• Goldberg, N.P. and Stanghellini, M.E. 1990.  Ingestion-egestion and aerial transmission of Pythium aphanidermatum by shore flies (Ephydrinae: Scatella stagnalis). Phytopathology 80, 1244-1246.
• Lindquist, R., Buxton, J. and Piatkowski, J. 1994.  Biological control of sciarid flies and shore flies in glasshouses. Brighton Crop Protection Conference, Pests and Diseases, BCPC Publications 3, 1067-1072.
• Morton, A., Garcia del Pino, F., 2007.  Susceptibility of shore fly Scatella stagnalis to five entomopathogenic nematode strains in bioassays. Biocontrol 52: 533-545.
• Morton, A. and Garcia del Pino, F. 2003. Potential of entomopathogenic nematodes for the control of shore flies (Scatella stagnalis). Growing Biocontrol Markets Challenge Research and Development. 9th European Meeting IOBC/WPRS Working Group “Insect Pathogens and Entomopathogenic Nematodes”, Abstracts, 67.
• Vanninen, I., Koskula, H. 2000. Biological control of the shore fly (Scatella tenuicosta) with steinernematid nematodes and Bacillus thuringiensis var. thuringiensis in peat and rockwool. Biocontrol Sci. Technol.. 13: 47-63.
• Zack, R.S. and Foote, B.A. 1978.  Utilization of algal monoculture by larvae of Scatella stagnalis. Environmental Entomology 7, 509-511.