A multidisciplinary team from the National University of Córdoba (UNC) developed a biopesticide based on natural compounds to control the weevil (Sitophilus zeamais) in corn. Made up of biologists, chemists and microbiologists, the initiative is directed by Julio Zygadlo and took four years of work to reach the result presented now.
The experiments began with the extraction of essential oils from aromatic plants, some native to Argentina such as peperina mint (Minthostachys verticillata) and thyme (Thymus vulgaris). The objective was to identify the components of the oils and their level of toxicity against pests, especially insects.
“The weevil that attacks corn is very harmful, because its entire life cycle develops inside the grain, eating the entire endosperm – which is the basis of nutrients”, points out one of the initiative's researchers, Jimena Herrera. She emphasizes that the formulation obtained based on natural compounds from these essential oils produces a synergistic interaction capable of combating weevils without toxic effects on corn.
According to the UNC, biopesticides should gain more and more space in Argentine agriculture as they are not harmful to human health and the environment. The synthetic insecticides most used to control weevils in that country - such as Phosphine (Phosphorus Hydride - PH3) and Bromomethane (Methyl Bromide) are banned and restricted (respectively) by the Argentine Ministry of Health.
According to the researcher, the indiscriminate use of some pesticides has made some pests resistant to these substances, which has led to applications of increasingly higher doses: “Facing this scenario, we could say that there are biopesticides that are more effective than synthetic ones. , in addition to acting faster, without affecting the raw material”.
Until now, UNC trials and tests have been carried out 'in vitro', under controlled conditions. The researchers' goal now is to move to larger scales to prove that the product does not deteriorate in external environments. “In the laboratory we obtained very good results, but it is necessary to expand field tests. But for this we need State policies and financial support, but above all a change in the conception of agricultural practices”, argues Jimena.
Source: Agrolink