How to fight the Lobesia Botrana early?

13/12/2016

The 2016-2017 season has started a few days in advance compared to the previous season due mainly to the temperatures presented from autumn to spring, having a direct impact on the early appearance of the first flowers and the harvest of fruit trees. .

As a result, the pests were no exception, and as expected, again a new fight against the cluster moth begins, Lobesia botrana, in a slightly anticipated way.

During last season, the strategy of the Livestock Agricultural Service (SAG) considered increasing the use of sexual confusion, a technique a little more expensive but that has shown good results. Although its effects are more complex to observe due to its mechanism of action, the use of the sexual confusion strategy allows avoiding all the errors associated with pesticide applications.

edith_fuentes This control technique can be used in different pests and consists of establishing a specific pheromone cloud for each pest in the field. The pheromone, on the other hand, is a chemical compound emitted by the female that helps the male to locate it to achieve the reproduction of the species. However, although this technique does not allow the monitoring of the pest using the known delta traps, the decrease of the individuals found in the fruit show us that it is an effective mechanism, whose results are increasing with their time of use.

In addition to sexual confusion, there is a list of 25 products authorized by the SAG (available on its website) that can be used to control the cluster moth. These products were fully evaluated in the field by the controlled infestation of artificial breeding individuals, establishing the control periods of each of them, both in the control of eggs and larvae. This procedure was carried out with all the products of the list, composed of 19 active ingredients ranging from pyrethroid to Bacillus thuringiensis.

In relation to the above, during this season we must be attentive to the time of application of pesticides and optimize the use of those alternatives that have demonstrated control over the different stages of the pest. It is important to carry out a monitoring, since the moments of greatest susceptibility will be determined by the climatic conditions of each zone. The high temperatures could cause an advance in the appearance of the pest, being absolutely necessary that the product applications are coincident with the position of the eggs and appearance of the first larvae.

Along with the times of application and the tools used for control, we must take into account that pesticides maintain their control for a period of time that must be respected, since windows during periods of protection reduce the effectiveness of control programs . During the first applications, the use of active ingredients with greater residuality should be prioritized, in this way the following applications will deal with assets with lower residuals as the harvest approaches.

About biological controllers for Lobesia, only trials of efficacy with Trichogram are being carried out, which is not yet authorized for use and commercialization for control by the SAG. Another technique of control is the TIE (sterile insect technique) that is not executable by producers, since it consists in the release of LB males previously sterilized with the use of radiation, which is extremely expensive and is also in the process of validation.

Finally, the control alternatives are varied and the strategies have shown to be effective in decreasing the density of the pest, even when this problem is far from over we must bear in mind that with each season we are approaching a more auspicious situation of eradication. So far the forecasts of propagation of the moth have not materialized, as well as the establishment in other productive species present in our country. However, it is essential that, in order to continue on a good path, we choose the eradication techniques following the corresponding measures for each one, in order that their effects are positive and allow us to incorporate them as basic prevention measures.

Source: Portal Frutícola - Edith Fuentes, Entomologist at the Rosario Center for Agricultural Research and Development, CER.