Concept

A complaint often heard from growers and from scientists in agricultural research and extension services is that lures from different suppliers and years of manufacture produce different results. This is not surprising since it is known that chemical purity strongly affects the attractiveness of a lure. Trace components at levels as low as 0.1% can act as synergists or antagonists, depending on the chemical structure. This means that every batch of lure, even prepared with the best quality control, may differ from others in attractiveness to target and non-target species. Another difficulty arises from the fact that strains of insects living on different host plants or in different parts of the world may use different pheromone blends.

Batch testing

Following these considerations, there is one logical way to obtain comparable results with pheromone lures: to prepare a batch of attractant sufficient to last for several seasons, give it an identification code, make sure it works, and use it as a standard. This procedure has been outlined in the "Budapest manifesto" adopted by a meeting of the IOBC Pheromone Group in 1997.

The PheroNet Idea

In the discussions following the Budapest meeting, the idea emerged that instead of working out recommendations and waiting for commerce to follow, it would probably be more efficient to create an organization capable of both producing and testing pheromone lures. This is how Phero.Net came into being.

Batch Certification

Batch certification of pheromone lures is a two-step process.

1) In a first step, a relatively large quantity of a pheromone blend is prepared and set aside under conditions which will guarantee that it will keep for a long period of time.

2) In a second step, lures are formulated on dispensers and tested in the field to determine if they are suitable for detection and monitoring. Only if this is the case the lures are put on the market.

The above procedure defaults to step one on two occasions:
a) if the results of the field tests are not satisfactory
b) as soon as the stock is close to depletion.
The same batch process is applied for the dispenser material. Step two should be repeated on occasion to assure continuing quality.

Our experience is that the typical monoenic acetate and alcohol pheromone compounds found in Lepidoptera can be stored at -18°C for many years without any noticeable deterioration. Under these conditions, some isomerisation can be observed with conjugated dienes; in Lobesia botrana this is of no importance as geometric isomers do not appear to be antagonists of the EZ isomer.

These tests should answer the questions: Is the lure attractive to the target species and what non-target species are caught. Based on previous experience and perhaps on experience with other products, can the Phero.Net lure be recommended for use in monitoring or detection.