Biological aspects and technical rearing of guava weevil, Conotrachelus psidii marshall

The species Conotrachelus psidii Marshall (Coleoptera: Curculionidae), considered a key pest of guava cultivation, is causing major damage in several producing countries of the fruit. The purpose of this study was to evaluate the biological parameters of the pest under controlled conditions, through the development of a rearing technique of pre-pupae and pupae that would allow daily observations. It was found that the substrate for an appropriate development of these phases was moistened clay soil (with survival rate of 78%). This soil type was used in the rearing method, which was developed to work in a climatic chamber at a constant temperature of 25 ± 1°C, 12 h photoperiod and 70% RH ± 10%. The biological stages of the egg, larva, pre-pupa, pupa and egg-pupa lasted, on average, 4.25, 12.2, 106.6, 14.88, and 138.4 days, respectively. The adult stages in the soil, beginning of feeding, pre-oviposition, longevity, and post-oviposition lasted on average 22, 11, 51.9, 149.32, and 7.18 days, respectively. The average oviposition period lasted 120.27 days, with an average of 343.63 eggs per female. By the proposed rearing method, the development of pre-pupae, pupae and adults of the guava weevil could be daily monitored, without requiring the construction of a new chamber by the insects, thus reducing stress and input in terms of energy. Index terms: Guava, biology, behavior. Considerada praga-chave da cultura da goiaba, Conotrachelus psidii Marshall (Coleoptera: Curculionidae) tem causado grandes prejuizos em varios paises produtores desta fruta. A pesquisa objetivou avaliar os parametros biologicos da praga, sob condicoes controladas, atraves do desenvolvimento de uma tecnica de criacao que permitiu efetuar observacoes diarias de pre-pupas e pupas. Constatou-se que o substrato adequado para manutencao dessas fases foi o solo argiloso umedecido com viabilidade de 78%, sendo este o tipo de solo utilizado na tecnica de criacao, que foi desenvolvida para trabalhos em camara climatizada, a temperatura constante de 25 ± 1° C, fotoperiodo de 12 horas e UR de 70% ± 10%. Quanto aos aspectos biologicos, a duracao media do periodo de ovo, larva, pre-pupa, pupa e ovo-pupa foi de: 4,25; 12,2; 106,6; 14,88 e 138,4 dias, respectivamente. A duracao media do periodo da fase adulta, no solo, inicio da alimentacao, pre-oviposicao, longevidade e pos-oviposicao foi de, 22; 11; 51,9; 149,32 e 7,18 dias, respectivamente. O periodo medio de oviposicao foi de 120,27 dias, com um num