Introduction Flashcards
Beneficial insects
- Insects that perform a valuable service in the environment such as
pollination and pest control. - Honeybees, butterflies, moths and many more…
Damage to crops by insects
Usually syntheticchemicals are used to stop insects but these are damaging to people and the environment
Phylum Nematoda
Phylum Nematoda consist of approximately 29 500 species and
approximately 16 000 are recognised as parasitic.
Nematode
- Nematode are microscopic species parasite to certain organisms.
- Nematodes are free living species in the soil, fresh water, marine
environment, etc.
Citrus EPN
nematode eating type
There are nematodes that feeds on fungi, plants, bacteria, insects, and
other nematodes.
Beneficial nematodes
Nematodes that feed on fungi or insects are called beneficial nematodes
(i.e. Entomopathogenic nematodes, etc).
* Beneficial nematodes help in bacteria population control and biological
control agent against crop pests.
nematode habitat
■ Reside in water films and in water filled pore spaces in the soil
■ lethal obligate parasites to insects
EPN genera
EPNs from the genera Steinernema, Heterorhabditis and Oscheius have
mutualistic associations with bacteria from the genus Xenorhabdus,
Photorhabdus and Serratia, respectively
ENT symbiosis
■ form symbiotic relationships with specific species of pathogenic bacteria
■ Work together with their symbiotic bacteria to infect and kill various types of
commercial crop insects
EPNs life cycle
IJs use external openings (anus, mouth, etc) to invade their host.
* Bacteria symbionts is released by the IJs into the Host gut to infect
and cause infections results into host death.
* This process take place parallel to EPNs feeding and reproduction.
* Depletion of food within the host result into emergence of the IJs into the environment and reset the life cycle.
The ITs eat the bacteria in order to
growandreproduce
EPN diagram