Nematodes are primitive unsegmented roundworms.
Nematodes are a Phylum of their own thus represent, a very large and diverse group of living organisms on this planet.
Most nematodes are completely harmless however a few families such as round worms (heartworm), which effect domestic pets and eelworms which cause billions of dollars worth of damage to crops, are major pests.
A number of significant human diseases are caused by Nematodes such as elephantiasis and African River blindness.
The CSIRO in Australia were the first organization to use Nematodes to control insect pests.
The Nematodes they discovered and used are now known as Entomopathogenic or (insect killing) Nematodes or EN’s for short.
EN’s come from two general Steinernematids and Heterorhabditids.
These are as different from the nematode species mentioned above as we humans are from goldfish.
What makes them unique is that they are predators of Larval insects and roam the soil following CO2 Gradients or increased levels of CO2 which indicate insect activity. Once they find an insect they enter it either through body cavities mouth anus etc or in some cases through thin membranes. What the CSIRO discovered was that by breeding these in vast numbers one could control insect pests that cause billions of dollars damage to crops, plants and trees and indeed turf. It is not until recently that this has become a commercial proposition, now that we have begun to realize the collateral damage caused by using Chemical pesticides.
Once inside they release a bacterium, that kills the insect host and then breaks down the tissue matter into food. The EN's use this food to mature and breed inside the insect cadaver.
In fact they breed very quickly, to as many as 100,000 or until the insect cadaver can no longer sustain the expansion in population and disintegrate releasing the EN's into the soil in search of new hosts.
To understand what happens we have graphed this interaction between predator and host.
In any given area lets say 1 Sq meter we can have from one to many hundreds of insect eggs which hatch into larvae which quickly start feeding of plant matter primarily juicy small
young roots thus depriving the plant of essential water and mineral absorption. (the pic to the left is of eggs larva in various stages)
For the purposes of our model we will assume 10 hosts per Sq meter and that each grub will host a colony of Ens which will quickly breed up to as many as 100,000 per host.
We apply the Ens by spraying them in at a rate of say 200,000 per Sq meter and in the application process we will loose a % (UV damage or Shearing in the process of being sprayed.)
Through infestation they quickly breed up inside the host resulting in the population expanding rapidly at the rate of 100,000 per host to 1 Million per Sq meter. (the graph below is of predator population against time)
The host population declines as infestation occurs until such time as all hosts are dead (the graph below is of host population against time)
Looking at the two together we see how this host predator relationship works graphically.
Season long control is possible where eggs hatch or different species of larva hatch over a number of weeks.
(the graph below is of host and predator population against time)
The product is supplied in a cellulose powder, which one simply dissolves in water which reactivates the ENs which we ship in a dormant state to preserve energy for when they are applied to the soil.
Depending on the application ie turf, Arbory or Horticulture the product is applied by an appropriate spray system, see photos
This is appling En's using boom spray.
Injecting shade trees in Northern China to control carpenter worms.
Spraying S.Carpacapesae beneath apple trees to control fruit borer larvae (Carposina) in China
Disinfecting blackcurrant cuttings with S.feltiae