Biological treatment with Heterorhabditis Bacteriophora (HB) nematodes against pests and/or harmful insects

Nematodes are microscopic worms that penetrate insect pest larvae and release symbiotic bacteria. These bacteria transform the host tissues into assimilable nutrients allowing the nematodes to feed, grow and reproduce inside the host. This kills the pest within a few hours or days of infection.

Scientific name: Heterorhabditis Bacteriophora
General species: Entomopathogenic nematodes
Product category: Cultivation aid

• For protection against weevil and other beetles in a wide variety of crops
• Can be applied with standard spray equipment
• Highly soluble biodegradable formulation with long shelf life

Use for

Scarabs (Coleoptera):

• Otiorhynchus (Curculionidae): Vine Otiorhynchus (Otiorhynchus sulcatus) and other Otiorhynchus spp.
• White grubs (Scarabaeidae): European beetle (Amphimallon majale); June beetle (Amphimallon solstitialis); Amphimallon aestivus; common cockchafer (Melolontha melolontha); European beetle (Phyllopertha horticola); Phyllophaga spp.; silver beetle (Hoplia philanthus) and other Hoplia spp.; Japanese beetle (Popilia japonica); oriental beetle (Anomala orientalis); Asian Garden Chafer (Autoserica castanea); bronze cockchafer (Anomala dubia); brown beetle (Serica brunnea); Anoxia villosa
• Dung beetles (Aphodius spp.)
• Leaf beetles (Chrysomelidae): Flea beetles (Phyllotreta spp.)

Caterpillars (Lepidoptera):

• Lesser hop beetle (or louvette) (Korscheltellus lupulina)

...

mode of action

The nematodes penetrate the larva of the insect pest and release symbiotic bacteria into the body cavity of the pest. These bacteria transform the host tissues into assimilable nutrients allowing the nematodes to feed, grow and reproduce inside the host. This kills the pest within a few hours or days of infection.

Activity indices

Infected pests are usually hard to find. Infected leaf pests simply fall to the ground. Infected insect pests in the root zone turn yellow to brown but may be difficult to see due to rapid breakdown.

Stage of development

Third-stage infective larvae (L3)

Concentration

86% Heterorhabditis Bacteriophora – 14% biodegradable inert carrier.

Preparation

Remove the sachets from the box and keep them at room temperature for 30 minutes
Empty the contents of the sachets into a bucket containing at least 2 liters of water per sachet (water temperature: 15-20°C (59-68°F))
Mix well and soak the solution for five minutes
Mix again and pour the contents of the bucket into the half-filled spray tank (unless mixing with a compatible product)
Continue to agitate the solution (using a recirculating pump, for example)
Fill the sprayer tank with the required amount of water
If mixing with a compatible product, add Steinernema feltiae last when the spray tank is completely filled.
Apply directly after preparing the spray solution.

Application

Nematodes can be applied with a watering can, Airblast sprayer, sprinkler, backpack sprayer or vehicle sprayer
To avoid blockage, remove filters, especially if the opening is less than 0.3 mm (50 mesh)
Use a maximum pressure of 20 bar / 290 psi (at the nozzle)
The aperture of the spray jet must be at least 0.5 mm (500 microns – 35 mesh); preferably use hollow cone jet type nozzles with high output
Mix continuously to prevent the nematodes from falling to the bottom of the tank
Avoid sprayers equipped with a centrifugal or piston pump
The water temperature in the sprayer tank should not exceed 25°C (77°F) and the pH should be between 4 and 8
Spray the solution evenly on the surface of the soil/growing medium

Dose

Heterorhabditis Bacteriophora is typically applied at 250,000 to 500,000 nematodes per m² for soil applications and 1 to 3 million nematodes per liter for foliar applications (application to runoff point).

Timing of application

The timing and frequency depends on the pest species and the crop environment (relative humidity, soil moisture and temperature).

Side effects and compatibility

Pesticides can have (in)direct effects on biological solutions. As a general rule, when mixing directly into the spray tank, always add the nematodes last to the fully filled tank containing the compatible product. The product is safe for most beneficial insects and mites, but may have some effect on a few when in direct contact with foliar applied nematodes.

IMPORTANT

• Store cool at 2-6°C (do not freeze) in the refrigerator after receipt until use and protected from light.
• Bring to room temperature for 30 minutes before use.
• To be used as soon as the temperatures are between 16 to 35° C.
• Use early morning or late evening to avoid UV, as nematodes are UV sensitive.
• Nematodes are not afraid of heat (<30°C), keeping them cold only aims to plunge them into cryptobiosis, thus keeping them in a state of lethargy.
• At room temperature, the nematodes continue their development. On the other hand, without "food", they will eventually die of "starvation" after about a week.
• Spraying: Remove the filters, use a nozzle diameter > 0.5 mm (35 mesh), prefer a high-flow hollow "conical jet" type nozzle.
• Do not keep the solution once diluted in water, the nematodes would eventually die of asphyxiation.