ABSTRACT

The present study was conducted at the Unidade de Pesquisa e Desenvolvimento de Gália, Pólo Regional de Desenvolvimento Tecnológico dos Agronegócios do Centro Oeste, in 2004 with the aim to evaluate the biology and production of silkworms when exposed to Mirabilis jalapa extracts (Family: Nyctaginaceae). This work was based on previous studies in laboratory conditions that showed that the aqueous extract of Mirabilis jalapa at 10% of concentration provided a 100% of protection for the insect against infection by polyhedrose virus (BmNPV). In commercial rearing conditions, the extract was used in different larval stages. Both in laboratory conditions as well as in commercial rearing the extract did not cause decrease effects in the biology and production of silkworms when compared with nontreated groups. Although the insects were infected by BmNPV, there were not observed symptoms of the infection, suggesting that the viral population, although present, was maintained at reduced levels, not causing a decrease of productivity performance. There was not observed an anticontaminant action of the extract against other opportunist pathogens since the rearing sanitary conditions were good, there occurring a few deaths probably related more with natural factors than to the occurrence of diseases.

KEY WORDS
Anticontaminant; vegetal extracts; natural inhibitors; biomolecules; silkworm; Bombyx mori L.