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Abstract: Light and stereomicroscopy examinations of Anticarsia gemmatalis multicapsid nucleopolyhedrovirus (AgMNPV)-infected insects were performed in order to follow infection in its host, A. gemmatalis. Fourth-instar A. gemmatalis larvae were infected by administration of occluded virus (polyhedra) from two recombinant AgMNPV viruses (vAgEGTΔ-lacZ or vAgGalA2) directly into the larvae foregut. The recombinant virus vAgEGTΔ-lacZ has the β-galactosidase gene (lac-Z) of Escherichia coli under the control of a constitutive promoter (hsp70 from Drosophila melanogaster). The vAgGalA2 virus has the reporter gene lac-Z under the control of the AgMNPV very late polyhedrin gene promoter. At different times post-infection (p.i.) the infected larvae were dissected, fixed, and the product of the expression of the lac-Z gene detected by incubating the insects in a buffer containing X-gal. This allowed us to follow the infection through the blue cells (due to the degradation of X-gal by the enzyme Lac-Z). Insect larvae inoculated with polyhedra from the recombinant viruses showed midgut cells to be infected first, followed by tracheal cells, hemolymph, fat body, Malpighian tubules and brain cells. The infection was similar for the two recombinant viruses, with blue cells appearing earlier in insects infected with the vAgEGTΔ-lacZ virus when compared to the vAgGalA2 virus. [Copyright &y& Elsevier]

• Cassava starch could adequately microencapsulate Siparuna guianensis essential oil. • Microencapsulation increased the stability of S. guianensis essential oil. • Microparticles of S. guianensis essential oil showed prolonged larvicidal activities. • Essential oil microencapsulated particles had low toxicity on zebrafish embryos. Due to the production facilities and great functionalities, the starch extracted from Cassava plants' (Manihot esculenta Crantz) roots is one of the most abundant and inexpensive raw materials used in food- and non-food industries. The utilization of starches to encapsulate plant essential oils is a relevant advance in the control of insect pests, including mosquitoes that transmit human diseases. The starch-based microencapsulation of essential oils reduces the degradation and volatilization of active components, providing more sustainable and environmentally friendly activities. Here, we investigated the potential of cassava-based starch microparticle preparations containing the essential oil of a Neotropical plant (Siparuna guianensis Aublet) to control larvae of Aedes aegypti and Culex quinquefasciatus. Moreover, the selectivity of the most efficient microparticles preparation was evaluated on zebrafish embryos (Danio rerio), an aquatic non-target organism. The characterization of encapsulated microparticles was achieved by using scanning electron microscopy (SEM), infrared spectroscopy with Fourier transform (FTIR), and thermogravimetric analysis (TGA). Our results revealed an encapsulation efficiency of 82.8 % to 95.3 %, with an average particle diameter of 8.56 μm. Cassava starch microencapsulation reduced the essential oil degradation and enhanced (up to 8 days) the persistent lethal activities (over 50 %) against both species' mosquito larvae compared to the pure essential oil. Furthermore, the exposure of aquatic non-target organisms (embryos of D. rerio) revealed these microparticles' adequate selectivity. Collectively, our findings demonstrate that cassava starch-based microparticles exhibit promising functionality as carriers for essential oils with mosquitocidal activities. [ABSTRACT FROM AUTHOR]