Comparative analysis of the effects of the biopesticide Azadirachtin and the synthetic insecticide Piriproxifem on the testes of Ceraeochrysa claveri (Navas, 1911) (Neuroptera: Chrysopidae). A morphological, ultrastructural and molecular approach

Author(s)

Ana Silvia Gimenes Garcia

• Document type: Doctoral Thesis
• Press: Botucatu. 2021-08-25.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências. Botucatu
• Defense date: 2021-06-29
• Advisor: Daniela Carvalho dos Santos

Abstract

Insects of the Chrysopidae family are natural enemies used in biological control, being an important tool in organic agriculture and in integrated pest management. In addition to the biological control using these insects, the use of natural insecticides has gained great prominence, as they are less harmful to man and the environment. However, the use of synthetic insecticides is still very high and ends up interfering in the life cycle of natural enemies, and consequently, in the biological control of pests. In order to evaluate the effect of azadirachtin and pyriproxyfen on the testes of the chrysopid Ceraeochrysa claveri, insects were exposed to these compounds in concentrations 12 and 36mg ia / L for azadirachtin (commercial formulation Azamax®), and 50 and 100mg ia / L for pyriproxyfen (commercial formulation Tiger 100 EC®). Adult testes were evaluated using morphological techniques and transcriptome analysis, in addition to assessing the life cycle of insects, fecundity and fertility. The results showed that the two insecticides caused few morphological changes in the testes, such as spacing between the cysts, and changes in the tunic that covers it. The treated groups showed no changes in the markings of the actin filaments and microtubules, as well as in the statistical analyzes, where there was only a reduction in fecundity, but maintaining the viability of the generated individuals. The analysis of the transcriptome pointed out a difference in the expression of the genes of nucleoporins, ribosomal proteins and zinc finger, which may be related to the process of spermatogenesis and fecundity of insects. These results show us that the two insecticides may be suitable for use in management programs that aim to conserve and increase the population of natural enemies, however the compatibility in the field of these insecticides with C. claveri must be evaluated. (AU)

• FAPESP's process: 17/09901-1 - Comparative analysis of the effects of the biopesticide Azadirachtin and the synthetic insecticide Piriproxifem on the testes of Ceraeochrysa claveri (Navas, 1911) (Neuroptera: Chrysopidae). A morphological, ultrastructural and molecular approach.
• Grantee: Ana Silvia Gimenes Garcia
• Support Opportunities: Scholarships in Brazil - Doctorate