Whitefly breed most resistant to insecticides is found in Mato Grosso

For the first time, researchers detected the presence of whiteflies (Bemisia tabaci) of the Q biotype in Mato Grosso. Considered invasive in Brazil, this breed is characterized by being naturally more resistant to a range of insecticides used in agriculture. The individuals were located in a flower shop in Sinop (MT). It is not yet known whether this breed is already present in crops in the region.

The identification was made in a work coordinated by Embrapa Agrossilvopastoril researcher Rafael Pitta, with the help of undergraduate students from the Agronomy course at UFMT, and with the help of researchers from Unesp (Botucatu-SP), where the identification was made through of molecular biology. DNA analysis is the only way to differentiate breeds, as they are visually identical.

The Q biotype whitefly originates from the Mediterranean region. It was collected and identified for the first time in Brazil at the end of 2013 by a group of researchers on crops in Rio Grande do Sul. Since then it has been spreading throughout the country, already being present in the southern states, in São Paulo and also in Goiás Transmitting viruses, the whitefly causes damage to several crops, with the greatest economic impact on peppers, soybeans and cotton.

According to Rafael Pitta, the initiative to search for the pest in Mato Grosso began after attending a presentation at a scientific event in which he saw that this breed of whitefly is present in flower plantations in the state of São Paulo. As plants from that region are sent throughout the country, there would possibly already be individuals in other regions.

Students of a subject taught by Rafael in the UFMT Agronomy course collected whiteflies from tomato plants, hibiscus, cat's tail, angel's trumpet and lantana in a flower shop and in the gardens of their own homes. Of all the individuals analyzed, two of the five present in the lantana were biotype Q. The rest were biotype B, more common in the region.

The researcher explains that the discovery opens up the need for new research to verify whether this breed of whitefly is already present in the state's crops. The greatest risk is for soybean and cotton crops.

“As this breed is resistant to a range of insecticides, spraying crops could select individuals of this breed, making whitefly control more difficult and more expensive”, explains Rafael Pitta.

According to the researcher, until further investigation is undertaken, the best prevention tool is integrated pest management (IPM).

“The exaggeration in the applications increases the selection pressure of this breed, favoring its establishment in the crops. The best thing to do is to monitor the crop and only apply the insecticide when the infestation reaches the level of damage”, guides the researcher from Embrapa.