Eficácia de Bacillus thuringiensis (Berliner) e spinosade no combate a Helicoverpa armigera (Hbn) (Lepidoptera: Noctuidae) em tomateiro

• Author(s): Pinóia, Sara Sofia Ferreira
• Date: 2012
• Persistent ID: http://hdl.handle.net/10400.5/5297
• Origin: Repositório da UTL
• Subject(s): tomato; Bacillus thuringiensis; Helocoverpa armigera; spinosad; tomato fruitworm; damages
• Document Type: Master thesis
• Language: Portuguese
• Advisor(s): Oliveira, Elisabete Lacerda de Figueiredo; Mexia, António Maria Marques
• Contributor(s): Repositório da Universidade de Lisboa

Description

Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia

In this study, assays were carried out to evaluate the efficacy and the persistence of products based on Bacillus thuringiensis and spinosad, in tomato protected crop and for Helicoverpa armigera control. These assays were performed at two different periods: July-August and October. Efficacy was evaluated 10 days after treatment and the residual activity (persistence) during 5 days (1st assay) and 7 days (2nd assay). In greenhouse, a reduction of 97.7% and 91.7% on H. armigera population (artificial infestation) and fruit damage rates of 15.8% and 13.7% were observed in the experimental plots treated with spinosad and B. thuringiensis, respectively. The mortality on H. armigera larvae caused by B. thuringiensis ranged between 41.7% and 58.3% (1st assay) and between 48.9% and 100.0% (2nd assay) along the days observation period, while for spinosad ranged between 85.7% and 100.0% in both persistence assays. There was also an abnormal evolution on the persistence of B. thuringiensis in the 2nd assay since the induced mortality in these repetitions increased along the observation period. It was concluded that spinosad presented higher efficiency and persistence, when compared to B. thuringiensis