José Maria Guzman Ferraz

Evaluation of a wettable powder formulation for the nuclear polyhedrosis virus of Anticarsia gemmatalis (Lep.: Noctuidae)

The influence of different carriers on the physical and biological stability of Baculovirus anticarsia wettable powder formulations was studied. The formulations were obtained by mixing the purified polyhedra of B. anticarsia with a carrier and drying the suspension in a bench spray dryer. Bioassays with Anticarsia gemmatalis Hubner showed that activity was maintained with the amorphous silica, attapulgite and kaolinite after a year of storage. In the presence of bentonite, activity declined 50% in the same period. All formulations, except kaolinite, maintained the physical parameters required of a good wettable powder. Kaolinite formulation showed reduction in wettability and particle agglomeration in storage.

Acción de inhibidores de la síntesis de la quitina en la reproducción de Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

The effect of benzoilfenylureas on the reproduction of Spodoptera littoralis (Boisd.) was studied. Third instar larvae were treated with either lufenuron or flufenoxuron by ingestion and contact (DL60 rate). The surviving larvae were observed until the adult stage. Adult males and females were mated in different combinations between treated and untreated individuals. The following variables were studied: average number of spermatophore, female fecundity and percentage of ecloded larvae (egg viability). A small change in spermatophore number (ca. 1 to 1.5) was noted specially in the combinations where males were obtained from treated larvae. The percentage of fecundity of females and hatched larvae decreased (ca. 45% and 30%) when both sexes were obtained from larvae treated with lufenuron and flufenoxuron.

Efecto del flufenoxuron sobre la actividad copuladora del macho de spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

The effect of benzoilphenylureas was studied on the copulating capacity of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) males. Two groups of third instar larvae were treated with flufenoxuron, one by ingestion and another by contact with an DL60 rate. After emergence of the adults, ten males of the each treatment were put individualy in a filter paper cylinder, from the first night until death, in the presence of a virgin female that shift daily. After the female death they were desiccated in order to see the presence or not of the spermatophore in the bursa copulatrix. It was observed that the S. littoralis males that proceeded from the flufenoxuron treated larvae did not change their copulating capacity. The metodology was considerate efficient to evaluate the copulate capacity of this specie males.