Cornelius Oosthuizen
Marketing & Technical Manager

The demand for biological products, such as beneficial predatory insects and mites, is growing rapidly. Export markets are imposing more restrictions, steering the industry to turn to Nature to find solutions to problems previously controlled with chemicals. Innovative solutions help protect, improve, and strengthen crops both above and below ground. Koppert’s biological portfolio has the unique ability to complement agrochemicals and offers a different mode of action within an IPM programme.

Looking at the changing industry landscape, drivers for using biological control, and specifically beneficial insects, are:

• Increased pressure by markets to reduce MRLs (maximum residue levels).
• An increase in costs associated with agrochemical
• Pest resistance to
• Improved efficiency of the beneficials used against selective pests.
• Enhanced control of persistent
• The negative impact of agrochemicals on biodiversity.
• A comprehensive beneficial portfolio is sufficient to offer full crop protection.

Whatever the reason for increasing your focus on biological control, some foundational steps need to be followed to ensure the successful integration in an IPM strategy.

1)  Planning of the IPM season

Good planning is the key to any successful crop protection strategy. Every crop and region has a unique set of conditions that determine the typical diversity and pressure of pests. Projecting for the season and what needs to be done will depend on the crop and location.

Currently, most crop seasons start with pre-scheduled pesticide applications. This is mainly based on experience and supported by scouting. The later part of the season is covered by releasing beneficial predators or parasitic wasps. It remains important to make sure the order of the season is clearly defined, since once beneficials have been released, the use of pesticides is limited, but not excluded.

If you are uncertain about the effect of a specific pesticide on beneficials, the Koppert Side Effects Database will provide all the assistance you need. The database can be accessed via the Koppert website, www.koppert.co.za, or the app can be downloaded from Google Play or the Apple App Store.

 2)  Selection of pesticides

Insecticides have a range of pests they can impact. Unfortunately, not all the different pests or types of insects or mites are indicated on the pesticide label. This is due to the pesticide registration regulations.

As an example, Movento is not registered against mites on table grapes, but the use of spirotetramat will impact the presence of beneficial predatory mites such as Spidex or Swirskii. Thus, if spirotetramat is scheduled to be used in a table grape programme against mealybug crawlers, then the use and release of predatory mites need to be scheduled accordingly.

Some pesticides are extremely harsh against certain beneficials. The application will have a long-lasting residual effect. This will imply that any release of beneficial insects within a limited time after pesticide application will lead to poor establishment and poor efficacy. Synthetic pyrethroids have a harsh immediate impact with a long-lasting toxic effect on beneficials.

3) Selection of the beneficial insect

The adaptability of beneficial species plays a very important role in the survivability in the area and in the crop of release.

The predatory mite Spical has a very wide host range compared to Spidex, which is limited to red spider mite species. Spical can feed off pollen, various mites and even crawlers of scale and mealybug. Thus, Spical will have a much better chance of surviving once the pest is under control.

4) Know the pest species

When using biological control and especially beneficial insects, it is vital that the pest species are correctly identified. This is especially true if parasitic wasps are used. Parasites are more selective than predators.

Citripar is a parasitic wasp that mainly targets citrus and vine mealybug. In the Letaba citrus production area the mealybug species Delottococcus iberiae occur.

This species is not parasitised by Citripar. So, predators of mealybug, Cryptobug or Nephubug, need to be introduced to control Delottococcus iberiae. It is thus very important to work with a Koppert Technical Advisor that specialises in your region.

5) Release technology

The method of release for a beneficial also plays a major part in the rate of establishment and survivability. Koppert has some unique methods to ensure accurate and effective releases of beneficials.

Natutec is the application technology arm of Koppert and manual release of beneficials can be done with the Mini Airbug. This small lightweight battery-powered applicator can distribute mites (Spidex, Spical, Swirskii, Thripex) across 6 meters.

This allows for the accurate distribution in crops like berries, vegetables and even fruit trees. We are also excited for the introduction of Natutec Drone.

Natutec Drone is a highly innovative way to do large-scale releases of beneficial mites and parasitic wasps like Pretiobug, with more products regularly being included in the portfolio to apply in this way.