* Crops with GM varieties have large infestations. The outcome has been to increase the number of pesticide applications

Maize farmers in Mato Grosso do Sul are concerned. They invested in GM seeds resistant to attack by caterpillars, only to see massive infestation in the crops. The solution was to increase the number of pesticide applications.

The farmer Edemilson Vincenzi cultivates 830 hectares of corn on a farm in the county of Maracaju. Seven years ago, he invested in a transgenic variety, which was supposed to be more resistant to pests. But in recent seasons, the efficiency has decreased and the farmer has had to increase the number of pesticide applications. The result was an increase in the cost of production.

The crop received three insecticide applications and you can still see damaged ears. After one, the worms ate the grains at will. The farmer explains that in [infestation] spikes like this, the production may fall by half.

The technology used in these transgenic varieties promises greater resistance to plant pests such as caterpillars and bugs, but for greater effectiveness we must always reserve an area for planting conventional corn, called the refuge area, which should be 5 to 10% of the total area.

The technique of refuge is not required, only a recommendation, and therefore is not always practiced by all producers, as Crébio Jose Avila, researcher at the Brazilian Agricultural Research Corporation (Embrapa), and expert in pest control, explains.

In other cases, also in Maracaju, 850 hectares were planted with corn with the same [GM] technology and another 260 hectares with the conventional type. Even following all the recommendations, insecticide applications were necessary, according to the farmer Renata Azambuja.

The researcher explains that the problem is not just seen in Mato Grosso do Sul. Producers from other states have also faced the same situation. "It is a widespread problem in Brazil because the non-adoption of the refuge area has been the main contributor to the development of resistance," says Crébio (Globo Rural, 2/7/14).

Source: BrasilAgro, July 3 2014
http://www.brasilagro.com.br/conteudo/ms-milho-que-deveria-resistir-as-pragas-traz-problemas-para-produtores.html#.U8UHzajgXn0
(English translation of Portuguese original by Google/GMWatch)