Entomopathogenic nematodes used for insect control belong mainly to the genera:

Correct option is B

· Biological control nematodes include:
· Steinernema spp.
· Heterorhabditis spp.
· They release symbiotic bacteria to kill insect hosts.
· Extensively documented in ICAR Entomology & Nematology.
Why other options are wrong
· (a) Meloidogyne & Heterodera = plant-parasitic.
· (c) Saprophytic or fungal feeders.
· (d) Root-lesion & reniform nematodes → plant parasites.