Paulo Cesar Rodrigues Cassino

Análise faunística de moscas-das-futas (Diptera: Tephritidae) da região noroeste do estado do Rio de Janeiro

This paper aimed to characterize the fruit fly populations in four municipalities of the Northwest region of Rio de Janeiro State (Bom Jesus do Itabapoana, Italva, Itaperuna and Natividade), performing a faunistic analysis of the specimens of fruit fly collected with plastic McPhail traps in commercial orchards of guava (Psidium guajava L.) and orange (Citrus sinensis Osbeck), and backyard gardens during a two year period. The total of 29,909 females of Ceratitis capitata (Wied.) and 27,621 females belong to 16 species of Anastrepha Schiner was collected. The highest value of the Shannon index was reported in Bom Jesus do Itabapoana (H = 0.96), as well as highest species richness (S = 14). Fruit fly populations had low diversity indexes (a = 1.1 - 1.5). The predominant species (more frequent, more abundant, constant and dominant) were C. capitata in Natividade and Bom Jesus do Itabapoana, and A. fraterculus (Wied.) in Italva and Itaperuna. Regarding fruit fly species composition, the population in Natividade and Bom Jesus do Itabapoana were more similar between each other, composing a distinct group of the fruit fly populations from Italva and Itaperuna, which composed another group.

NATIVE HYMENOPTERAN PARASITOIDS ASSOCIATED WITH ANASTREPHA SPP. (DIPTERA: TEPHRITIDAE) IN SEROPEDICA CITY, RIO DE JANEIRO, BRAZIL

Parasitoids associated with five species of Anastrepha were recovered from host fruits that belong to 12 species of plants growing in Seropedica city, Rio de Janeiro, Brazil. We recovered six native hymenopteran parasitoid species: Doryctobracon areolatus (Szepligeti), Utetes (Bracanastrephae) anastrephae (Viereck), Opius bellus Gahan (Braconidae, Opiinae), Aganaspis pelleranoi (Brethes) (Figitidae, Eucoilinae), Trichopria anastrephae Lima (Diapriidae, Diapriinae) and an unidentified species of Pteromalidae. The most abundant parasitoid species was D. areolatus, representing 61.8% of all parasitoids. The parasitoid species recovered were well established in a wide diversity of fruit and Anastrepha fly species, including economically important pests such as A. fraterculus, A. obliqua and A. sororcula. The analysis of the relative abundance of the recovered parasitoids in different fruit species suggests, at least for the three encountered opiine parasitoids, that the host-parasitoid relationship was influenced by certain physical characteristics such as size and weight of the host fruit. Our results support the original proposal of M. Aluja and J. Sivinski (pers. comm.) that some native host plant species for the Anastrepha flies facilitate parasitoid multiplication. They deserve attention as natural enemy reservoirs and may be important to biological control strategies within fruit fly integrated management programs.

Diversidade de moscas-das-frutas em pomares de citros no município de Araruama, RJ

This study was aimed at determining the species of Tephritidae and Lonchaeidae (Diptera: Tephritoidea) that occur on groves of sweet orange (Citrus sinensis Osbeck ) and tangerine (Citrus reticulata Blanco) in the municipality of Araruama, state of Rio de Janeiro, Brazil, from December, 2002 to November, 2003. The specimens were collected by McPhail traps with aqueous solution of hydrolyzed protein to 5% and in fruits samples of six varieties of citrus. In the traps the total of 2,543 adults of Tephritoidea (1,430 females and 1,023 males) was captured, being ten species of Tephritidae, four species and two morphotypes of Lonchaeidae. From the Tephritidae caught by the McPhail, four species (Anastrepha fraterculus, A. obliqua, A. sororcula and Ceratitis capitata) infested citric fruits while the Lonchaeidae, the morphotypes did not infest the citrus. The results showed that the population density of fruit flies may be overestimated when based on the number of flies per trap due to the capture of species that not infest the fruits of commercial interest.

Distribuição de insetos fitófagos (Hemiptera: Sternorrhyncha) em plantas cítricas no estado do Rio de Janeiro

The phytosanitary problems leading to lower citrus production in the state of Rio de Janeiro are due to the insufficient knowledge on insect species affecting citrus orchards. The objective of this research was to study the geographic distribution of phytophagous insect species, associated with citrus production, in 17 municipalities of Rio de Janeiro, from January 2000 to June 2001. The municipalities are located in four regions: Baixada Fluminense (the lowland region), Regiao Serrana (the mountain region), Regiao das Baixadas Litorâneas (the citrus producing marshland region) and Regiao Noroeste (the Northern region). Samples were collected from one orchard in each municipality by means of the presence or absence methodology. Eleven species were found in three municipalities and six species were found in three others. The species Aleurothrixus floccosus (Maskell) and Selenaspidus articulatus (Morgan) were found in 16 municipalities. Lepidosaphis beckii (Newman) and Toxoptera citricida (Kirkaldy) were found in only seven and 10 municipalities, respectively.

Novos registros de moscas-das-frutas (Diptera: Tephritidae) no estado do Rio de Janeiro

This paper reports the first record of the following Anastrepha species in the state of Rio de Janeiro: A. barbiellinii Lima, A. bistrigata Bezzi, A. manihoti Lima, A. minensis Lima and A. zenildae Zucchi. The number of Anastrepha species recorded in this state increased to 26.

Impacto dos nutrientes N e K e de açúcares solúveis sobre populações de Diabrotica speciosa (Germar) (Coleoptera, Chrysomelidae) e Agrotis ipsilon (Hüfnagel) (Lepidoptera, Noctuidae) na cultura da batata, Solanum tuberosum L. (Solanaceae)

The occurrence of Diabrotica speciosa (Germar, 1824) and Agrotis ipsilon (Hufnagel, 1767) on the potato cultivars Achat and Monalisa, influenced by nitrogen and potassium dosage, and minimum theor of soluble sugars, was studied. The following parameters were evaluated: concentration of mineral nutrient and sugar in green leaf, senescent leaf, leaf in abscission, stem, tubercle and total plant using extracts of infusion in ethanol 80%. The largest infestation of D. speciosa larvae was on Monalisa cultivar at 150 kg.ha-1 of N + K with 27.03% at P< 0,05. It was observed that the effect of the dosage of N + K in the increment of the concentration of soluble sugars increased the damages in the tubercles and stems by A. ipsilon. The infestation by these species increased to 58.82% on the Monalisa cultivar, when the nitrogen dosage increased from zero to 150 kg.ha-1, in the absence of potassium. On the other hand, high dosage of K reduced the damages by A. ipsilon on Monalisa cultivar. However, it did not influence the storage of soluble sugar. The results indicated that in Achat cultivar the accumulated soluble sugar was reduced, probably sensibilized by elevation of potassic fertilization dosing, differing from Monalisa cultivar, in which the influence was by nitrogen dosing.

Plano de amostragem presença-ausência para Selenaspidus articulatus (Morg.) (Homoptera: Diaspididae) na cultura da laranja

The efficiency of a binomial sampling (presence-absence) technique for Selenaspidus articulatus (Morg.) in citrus orchards was evaluated. The spatial distribution of scales was aggregated, according to Taylors law power coefficients (b = 1,636; a = 5,772). Regression analysis between the estimated proportion of infected leaves, resulted in a high determination coefficient, explaining 85,4% of the model. The number of sample unities (leaves) required to estimate infestation density was low, allowing practical application of this metodology to monitor S. articulatus populations.

Ocorrência de Selenaspidus articulatus (Morgan) (Hemiptera, Diaspididae) e do predador Pentilia egena (Mulsant) (Coleoptera, Coccinelidae) em Myrtus communis L. (Myrtaceae), em Pinheiral, RJ

Occurrence of Selenaspidus articulatus (Morgan) (Hemiptera, Diaspididae) and of the predator Pentilia egena (Mulsant) (Coleoptera, Coccinelidae) on Myrtus communis L. (Myrtaceae), in Pinheiral County, Rio de Janeiro, Brazil. The evaluations were conducted weekly in the vegetative and blooming/fructification phases in four quadrants (N, S, E, W) of the plant. It was collected 2,230 specimens of S. articulatus, 1,224 in the vegetative phase and 1,006 in the blooming/fructification, being 59,8% adults. From the total of 965 of P. egena, 416 were immatures and 549 adults. The main conclusions are: (1) M. communis may be indicated as plant bait; (2) this plant, may be cultivated or not around the crops of economic importance, because it may function as a reservoir of the pest or of its natural enemies; (3) the relation predator/prey/plant quadrant/phenology phases was, respectivelly, 1.14:1.0 and 1.0:1,08 in north and east quadrant; while in south and west quadrant was 1.0:2.26 and 1.0:2.80; and, (4) the predaction of S. articulatus by P. egena was, in average, 1.0-2.8 nymphs and 1.66-4.44 adults (in vegetative phases) and 1.0-3.76 and 1.0-3.98 (in blooming/ fructification), with significant differences at P< 0.01.

Avaliação da infestação de insetos-praga associados à batata (Solanum tuberosum L.) sob efeito de nutrientes nitrogenados e potássicos e teores acumulados de aminoácidos livres nas cultivares Achat e Monalisa

Evaluation of insect-pest infestation associated to potato (Solanum tuberosum L.) under effect of nitrogen and potassium fertilizers and the accumulated amount of free aminoacids in Achat and Monalisa cultivars. The objective of this work was to evaluate the occurence of insect-pests on potato plants influenced by dosages of nitrogen and potassium accumulated in plant organs. A total of 169 plants of the Achat and Monalisa cultivars were evaluated to determine the presence-absence of Diabrotica speciosa Germar, 1824 and Agrotis ipsilon Hufnagel, 1767. The experiment was carried out and executed at the Universidade Federal Fluminense, and the delineation was complete randomized block design, with four replication and nine treatments, using three fertilization level (0; 75 and 150 Kg/ha) with N-urea + KCl. The aminoacid levels were adjusted by the Leucine standard-curve (µg/l), using the Ninhydrin method, at 570 nm. The results showed that the tubercles of Monalisa accumulated high free aminoacid levels with 7,95% in the treatment N1K2 and 7,75% in the N2K1.These treatments, induced the infestation by D. speciosa larvae in 27,03%, when the aminoacid level was 2,01 ± 0,58% (X ± EP), with probability of 0,0196<P<0,05. The studied cultivars showed a diferential behavior, especially, in relationship to the N and K metabolism, resulting in the accumulation of free aminoacids, and consequently in the pest infestation increment. The results indicated that the aminoacid level increasing affects the tubercles production, mainly in the Monalisa cultivar, in winter cropping with long dry periods.