ABSTRACT Parasitoids of the genus Trichogramma are promising for the biological control of insect pests in several crops, including cassava, which is severely attacked by Erinnyis ello L., 1758 (Lepidoptera: Sphingidae). Evaluating the biological aspects of these parasitoids to understand their dynamics is an important step towards the implementation of this control strategy in the field. Thus, our objective was to evaluate the biology of Trichogramma manicobai Brun, Moraes & Soares, 1984, and T. marandobai Brun, Moraes & Soares, 1986 in E. ello eggs. The parasitoids were obtained by collecting E. ello eggs from a commercial production of cassava, and the host’s eggs were obtained from laboratory and greenhouse rearings. The average duration of a generation (T), net reproduction rate (R0), intrinsic rate of increase (rm), and the finite rate of increase (λ) were estimated, and from these, the fertility life table was calculated. The results indicated that T. marandobai has both higher net reproduction rate and a higher intrinsic rate of increase as well as requires less time to double its population than T. manicobai. Thus, T. marandobai has potential for natural and conservative biological control of E. ello. In addition, its potential in applied biological control should be evaluated through studies on the viability of its mass rearing in alternative hosts and its dispersion behavior in the field.

ABSTRACT Vatiga manihotae (Drake 1922) (Hemiptera: Tingidae) is an important cassava pest due to the great potential damage and the increasing population in recent years. However, few studies about bioecology and control of the cassava lace bug have been conducted and their results don't provide adequate control strategies. An alternative to maintain the population below economic injury levels is through the adoption of host plant resistance. To improve the understanding about the bioecology and find new sources of resistance in cassava, the biological parameters and demographics of V. manihotae on five cassava genotypes (Santa Helena, MEcu 72, Col 22, Clone 02 and Clone 03) under controlled conditions (25±2°C, 14L/10D) were evaluated. Duration and viability of the stages, the period egg-adult, sex ratio, the pre-oviposition period, fecundity and longevity of male and female was determined, and a fertility life table was prepared. Insects fed on MEcu 72 showed increased nymphal, egg-adult, and pre-oviposition periods and reduced female fecundity and longevity in comparison to the other genotypes. Demographic parameters (Ro, rm, T, DT) showed a significant impact on the growth potential of V. manihotae fed on MEcu 72 indicating that the populations would diminish over time. The combined effect of these parameters indicated that MEcu 72 has resistance on V. manihotae specimens hindering their development.

Resumen El objetivo de este estudio fue desarrollar un método de cría de Bemisia tuberculata en plantas de yuca para la producción y el mantenimiento continuo de una colonia. La población inicial de B. tuberculata se obtuvo a partir de hojas recogidas de la planta con alta infestación de ninfas. Los adultos obtenidos fueron transferidos de la taza de plástico a jaulas de tul, en diferentes densidades. La densidad de 125 adultos de B. tuberculata por hojas fue el más adecuado para la cría. El método que se propone en este estudio ha demostrado ser eficaz y se recomienda, ya que el nivel de la población se mantuvo estable durante los experimentos.

Abstract The aim of this study was to develop a rearing method for Bemisia tuberculata on cassava plants that enables the production and ongoing maintenance of a colony. The initial population of B. tuberculata was obtained from leaves collected from plants with high nymph infestations. Emerging adults were transferred from plastic cups to voile cages in different densities. The density of 125 adults of the B. tuberculata per leaf was the most suitable for rearing. The rearing method proposed in this study has proven to be effective and is recommended since it allows for population levels to remain stable during experiments.

Este trabalho registra a ocorrência de Aleurothrixus aepimGoeldi em plantas de mandioca na região Oeste do Paraná, Brasil. A espécie foi primeiramente encontrada em fevereiro de 2009, em área experimental da Universidade Estadual do Oeste do Paraná (UNIOESTE), em folhas de mandioca da variedade fécula branca. Os exemplares foram coletados recolhendo-se folhas infestadas com ninfas de mosca-branca, caracterizadas por apresentar corpo recoberto por filamentos cerosos de coloração branca. O material foi preservado em etanol a 70%, em frascos de vidro, e foram enviados para identificação. Novos surtos foram registrados no início de 2010 e 2011 em diferentes propriedades rurais localizadas no município de Marechal Cândido Rondon. Entretanto, a causa precisa da ocorrência de A. aepimnessa região não está totalmente clara. Nas demais regiões produtoras do Estado, esta espécie ainda não foi detectada.

This paper work recorded the occurrence of Aleurothixus aepim Goeldi in cassava plants in the West of Parana, Brazil. The species was first found in February, 2009, in an experimental area at Universidade Estadual do Oeste do Paraná (UNIOESTE), in cassava leaves of the white starch variety. The samples were collected by gathering leaves infested with whitefly nymphs, which are characterized for presenting body coated by white waxy filaments. The material was preserved in 70% ethanol, in glass bottles, and sent for identification. New outbreaks have been recorded in the beginning of 2010 and 2011 in different rural properties located in the city of Marechal Candido Rondon. However, the precise cause of the occurence of A. aepim in this region is not completely clear. In the other production regions of the State, this species has not yet been detected.