Aspectos biológicos e técnica de criação do gorgulho-da-goiaba, Conotrachelus psidii marshall (Coleoptera: Curculionidae)

Abstract

1 FABRICIO IGLESIAS VALENTE2 , VERA LÚCIA RODRIGUES MACHADO BENASSI 3 RESUMO-Considerada praga-chave da cultura da goiaba, Conotrachelus psidii Marshall (Coleoptera: Curculionidae) tem causado grandes prejuízos em vários países produtores desta fruta. A pesquisa objetivou avaliar os parâmetros biológicos da praga, sob condições controladas, através do desenvolvimento de uma técnica de criação que permitiu efetuar observações diárias de pré-pupas e pupas. Constatou-se que o substrato adequado para manutenção dessas fases foi o solo argiloso umedecido com viabilidade de 78%, sendo este o tipo de solo utilizado na técnica de criação, que foi desenvolvida para trabalhos em câmara climatizada, à temperatura constante de 25 ± 1º C, fotoperíodo de 12 horas e UR de 70% ± 10%. Quanto aos aspectos biológicos, a duração média do período de ovo, larva, pré-pupa, pupa e ovo-pupa foi de: 4,25; 12,2; 106,6; 14,88 e 138,4 dias, respectivamente. A duração média do período da fase adulta, no solo, início da alimentação, pré-oviposição, longevidade e pós-oviposição foi de, 22; 11; 51,9; 149,32 e 7,18 dias, respectivamente. O período médio de oviposição foi de 120,27 dias, com um número médio de 343,63 ovos por fêmea. A técnica de criação desenvolvida permitiu acompanhar diariamente o desenvolvimento de pré-pupas, pupas e adultos do gorgulho-da-goiaba, sem que eles necessitassem reconstruir nova câmara, mostrando ser menos estressante e onerosa do ponto de vista energético. Termos para indexação: Goiabeira, biologia, comportamento. BIOLOGICAL ASPECTS AND TECHNICAL REARING OF GUAVA wEEVIL, Conotrachelus psidii MARSHALL (COLEOPTERA: CURCULIONIDAE)ABSTRACT-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 ± 1ºC, 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.

Mapping the Spatial Distribution of Conotrachelus psidii (Coleoptera: Curculionidae): Factors Associated with the Aggregation of Damage

“…Adults emerge between 20 and 30 days in the rainy season, and females can survive 6 months and males can survive 9 months, on average. These results differ, in some aspects, from those reported by Bailez et al (2003) and Valente & Rodrigues (2014), who examined the biology of C. psidii under laboratory conditions, where the larval periods were reported as 8-27 days and 9-19 days, respectively, and the prepupal period was reported to extend from 84 to 229 days and 63 to 224 days, respectively, while the pupa stage was reportedly only 14-18 days. It is evident that these differences in the lengths of these three life cycles can be influenced by abiotic factors, especially in the prepupal state, which is the longest stage of the life cycle and where there is a great degree of variation.…”

Occurrence of Conotrachelus psidii (Marshall, 1922) in Psidium cattleianum (Sabine)

“…Conotrachelus psidii has a negative impact on the production and commercialization of fruit in several countries, including Brazil, due to early ripening and rotting, giving them an unpleasant appearance (Valente & Benassi, 2014). In addition to larvae damaging the fruit, adults may damage other plant organs, such as flower buds, petioles and stems (Silva-Filho et al, 2007).…”