Identification of target molecules for use in RNAi as a control of the agricultural pest Diabrotica speciosa (Coleoptera:Chrysomelidae)

Abstract

Agribusiness occupies a highly significant position in the political-economic-social interests in Brazil. One of the great challenges of agriculture is the constant threat of production losses due to biotic (pests, diseases, and weeds) and abiotic stresses (drought, frost, nutrition, among others), which cause damage to various crops, such as corn, soybeans, beans, potatoes, among others. An important pest of the corn crop is the Yellow-Green Cow (Diabrotica speciosa), whose damage extends to other crops, due to the polyphagous behavior of this species, which currently has its management limited to the use of chemical pesticides. The RNAi technology, a cellular mechanism for regulation of gene expression, is a sustainable alternative to the use of agrochemicals, because they are biodegradable molecules, non-toxic, and with a highly specific mechanism of action, allowing its combination with other sustainable technologies. Its operation occurs in insect cells through the identification of dsRNA sequences homologous to a gene with vital function for the insect, allowing silencing that results in its death. Several target molecules have already been identified and characterized in the species Diabrotica virgifera, revealing their potential for the control of Diabrotica by RNAi. This project proposes an evolutionary, experimental, and comparative approach, which consists in, based on molecular data available from the species D. virgifera, isolate, sequence, align and analyze orthologous genes in D. speciosa, thus defining the targets for RNAi mechanism, enabling the validation of studies committed to the development of a national product for the control of the pest.