Marcílio José Thomazini

Diversidade de abelhas (Hymenoptera: Apoidea) em inflorescências de Piper hispidinervum (C.DC.)

Este trabalho teve como objetivos determinar as principais especies de abelhas visitantes de inflorescencias de pimenta longa, Piper hispidinervum (C.DC.), sua abundância e frequencia relativas. Alem disso, verificaram-se tambem os seus horarios de visitacao e a influencia de fatores climaticos na variacao da abundância dessas especies. As coletas foram realizadas na area experimental da Embrapa Acre, com as amostragens efetuadas com auxilio de um aspirador de boca durante o periodo de julho de 1999 a junho de 2000, em um plantio experimental de pimenta longa, com aproximadamente 0,5 ha. As inflorescencias de pimenta longa foram visitadas por abelhas durante todo ano, sendo coletados 2555 individuos pertencentes a 20 especies de abelhas, das quais Augochlorini sp. (taxon proximo ao genero Pereirapis), Pereirapis sp., Scaptotrigona sp.1, Dialictus sp., Scaptotrigona tricolorata Camargo e Augochloropsis sp. foram dominantes. Augochlorini sp. e Pereirapis sp. foram mais abundantes nos meses menos chuvosos, ja as especies de Scaptotrigona nos mais chuvosos, enquanto as especies de Dialictus e Augochloropsis nao tiveram uma epoca de ocorrencia definida. A subfamilia Meliponinae predominou em numero de especies, enquanto que a familia Halictidae predominou em numero de individuos. De modo geral, as correlacoes significativas entre as variaveis climaticas e as abundâncias das especies dominantes foram baixas ou medias. Houve clara preferencia das abelhas por visitarem as inflorescencias de pimenta longa entre 8h e 9h da manha, o que pode estar relacionado a disponibilidade de recursos e ao aumento da temperatura durante o transcorrer do dia.

Insetos associados à cultura da soja no estado do Acre, Brasil

The soybean crop is increasing in the northern region of Brazil and it is in adaptation to local conditions of the State of Acre, which raises the possibility of occurrence of insect pests. For this reason soybean pests and their natural enemies were studied in eleven soybean cultivars planted in strips of 40 χ 8m (320m2) in 3520m2. An area of 80m2 in each strip received no insecticide. Four samplings were made each week in each strip (two samplings were made on each controlled and non controlled areas) with a beating cloth method. Stink bug eggs were collected aiming to evaluate parasitoidism level of soybean pests. The most abundant insect was Cerotoma tingomarianus Bechyne (Coleoptera: Chrysomelidae), with higher defoliation in the non controled area, while main predators were Lebia concinna Germar (Coleoptera: Carabidae), Callida sp. (Coleoptera: Carabidae) and Tropiconabis sp. (Hemiptera: Nabidae). Main seed sucking bugs were Piezodorus guildinii Westwood (Hemiptera: Pentatomidae) and Euschistus heros Fabr. (Hemiptera: Pentatomidae), with parasitoidism of 39.9 and 53.3% of eggs of those bugs, respectively. Telenomus podisi Ashmead (Hymenoptera: Scelionidae) was the most frequent parasitoid with 94.5 and 100.0% of eggs of P. guildinii and E. heros parasitized by this natural enemy respectively.

Parasitóides (Hymenoptera: Braconidae) de Anastrepha Schiner (Diptera: Tephritidae) no estado do Acre

This paper records the first parasitoids occurrence on Anastrepha Schiner fruit flies in the state of Acre, Brazil. In the Bujari County there occurred the braconids Opius bellus Gahan (72.5%), Doryctobracon areolatus (Szepligeti) (26.8%) e Utetes anastrephae (Viereck) (0.7%) associated with A. obliqua (Macquart) in tapereba fruits (Spondias mombin L.), with parasitism of 29.5%. In guajava fruits (Psidium guajava L.) at Rio Branco County, only D. areolatus on A. obliqua occurred, with parasitism of 2.7%.

Primeiro registro de espécies de Anastrepha (Diptera: Tephritidae) no estado do Acre

A fruit fly trapping survey was conducted on two orchards at Embrapa Acre, state of Acre, Brazil, from August/2001 to January/2002. The fruit flies were collected in traps with 10% sugarcane molasses as attractive. A total of 2,265 specimens, belonging to genus Anastrepha, were captured and 1,179 females were identified. The most common species was A. obliqua (Macquart) (98.8%). The other species occurred rarely: A. striata Schiner (0.9%), A. distincta Greene (0.2%), one specimen of A. leptozona Hendel, one specimen of A. tumida Stone and a not identified specimen. A. tumida was recorded for the first time in the Brazilian Amazon.

Tabela de vida de fertilidade de Muscidifurax uniraptor Kogan & Legner (Hymenoptera: Pteromalidae) em pupas de Musca domestica L. (Diptera: Muscidae)

The potential population growth of the parasitoid Muscidifurax uniraptor Kogan & Legner was determined in laboratory conditions (25±1oC, 70±10% R.H. and 14h of photophase). Thirty 0 to 24h old females of the parasitoid were individualized with 15 house fly pupae, 24 to 72h old. The survival of immatures of M. uniraptor was 97.2%. Female longevity was estimate in 13.17 days (mean), with intrinsic rate of natural increase of 0.22; liquid rate of reproduction of 119.01; finite rate of increase of 1.24; mean generation time of 21.93 days and duplication time of 3.18 days. These values demonstrated that M. uniraptor has a high potential of population growth.

Flutuação populacional e intensidade de infestação da broca-dos-frutos em cupuaçu

The most important pest of the cupuacu crop is the fruit borer, Conotrachelus humeropictus Fiedler (Coleoptera: Curculionidae), wich severely damages fruits and is disseminated all over North Brazil. The objectives of this study were evaluating the population fluctuations of C. humeropictus adults, infestation levels and to characterize the pest larval attack in cupuacu fruits of agroforestry systems of the Rondonia State, Brazil. Population fluctuations from C. humeropictus adults were evaluated weekly from March/98 to July/00 in twenty cupuacu plants, by shaking the tree branches, of two producer areas. During two harvest periods, fruits attacked by the borer were collected and examined for evaluation of larvae population. Pest infestation was determined by the percentage of damaged fruits. C. humeropictus adults occur year around on cupuacu plants, but predominate at the stages of flowering, fruit formation and during the harvest period. It was observed that mature and non-mature fruits are attacked by the pest; larvae of different ages can occur in a same fruit; the insect may cause losses greater than 50% of fruit yield.

Occurrence and damages of Danothrips trifasciatus (Thysanoptera, Thripidae) on Calophyllum brasiliense (Clusiaceae) in Brazil

Occurrence and damages of Danothrips trifasciatus (Thysanoptera: Thripidae) on Calophyllum brasiliense (Clusiaceae) in Brazil. Danothrips trifasciatus Sakimura, 1975 (Thysanoptera, Thripidae) is recorded for the first time in Brazil, in the municipality of Garca, Sao Paulo state. Individuals were collected in April 2011 damaging young leaves of guanandi, Calophyllum brasiliense Cambess. (Clusiaceae), forest species of increasing importance in Brazil. Future studies involving aspects on biology and population dynamics of the thrips in this plant species need to be carried out, in order to establish its potential economic importance to guanandi.

Ocorrência de Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) em citros no estado do Acre, Brasil

This paper records the occurrence of citrus leafminer, Phyllocnistis citrella Stainton, in citrus plants in the state of Acre, at Rio Branco County. The parasitoid Horismenus sp. (Hymenoptera: Eulophidae) is also registered emerging from pupae of the leafminer.

Ocorrência de Herminodes sp. (Lepidoptera: Noctuidae) em pupunheira nos estados do Acre e Rondônia, Brasil

Related herein is the occurrence of Herminodes sp. in peach palm plants at experimental area of Embrapa Acre, Rio Branco, AC and at Projeto Reca, Vila Nova California, RO, Brazil. The main characteristics of this insect and the damage it causes are described. This is the first record of Herminodes caterpillars damaging peach palm in the states of Acre and Rondonia.

Ocorrência da mosca-do-sorgo Stenodiplosis sorghicola (Coquillett) (Diptera: Cecidomyiidae) em genótipos de sorgo em Rio Branco, AC, Brasil

The first occurrence of Stenodiplosis sorghicola (Coq.) and the incidence of this pest on different sorghum genotypes were related in the State of Acre, Brazil. Panicles were collected ten days after the beginning of the blooming stage, and placed in emergence boxes. S. sorghicola ocurred on sorghum for forage and grain, with greater incidence on the first one. The genotype 698005 was the most atacked. The presence of S. sorghicola on sorghum in Acre revealed that this insect occurs in the region surviving, probably, on other Sorghum species.