Spatial and temporal dispersion of Doryctobracon areolatus (Szépligeti) (Hymenoptera: Braconidae) in orchards infested with Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae).

Doryctobracon areolatus (Szépligeti) is an endoparasitoid and promising fruit fly control agent. The objective of the study was to determine the spatial (horizontal and vertical) and temporal dispersion of D. areolatus in the field. To evaluate the horizontal and temporal dispersion, two peach orchards were selected. In each orchard, 50 points were marked at different distances from the central point, from where 4,100 couples of D. areolatus were released. Four hours after release, parasitism units (PU) (3 per point) were fixed to the trees at a height of 1.5 m from the ground. The PUs were composed of ripe apples artificially infested with second instar larvae of Anastrepha fraterculus (30 larvae/fruit). For the evaluation of vertical dispersion, in an olive orchard six points were selected (trees of ≈4 m in height). Each tree was divided into three heights in relation to the ground (1.17, 2.34, and 3.51 m). Doryctobracon areolatus was able to disperse horizontally at a distance >60 m from the release point. However, the highest parasitism rates [15-45% (area 1); 15-27% (area 2)] were observed up to 25 m. Higher percentages of parasitism and of recovered offspring occur in the first days after the release of the parasitoid (2 DAR). As for vertical dispersion, D. areolatus parasitized A. fraterculus larvae up to the highest attachment height of the evaluated PUs (3.51). The results showed the potential use of D. areolatus in the management of fruit flies in the field.

Lethal and sublethal effects of toxic bait formulations on Doryctobracon areolatus (Hymenoptera: Braconidae) and implications for integrated fruit fly management.

The use of toxic baits has become one of the main methods of management of fruit flies in Brazil. The application of toxic baits may cause side effects on the native parasitoid Doryctobracon areolatus (Hymenoptera: Braconidae). Based on the results, formulations made from the food attractants 3% Biofruit, 1.5% Ceratrap, 1.25% Flyral, 3% Isca Samaritá, 3% Isca Samaritá Tradicional, and 7% sugarcane molasses associated with the Malathion 1000 EC and the ready-to-use toxic bait Gelsura (containing the active ingredient alpha-cypermethrin) were classified as harmful (class 4) to D. areolatus (mortality > 85% at 96 HAE). In contrast, for toxic baits formulated with insecticide phosmet, the mortality ranged from 38% to 72%, classified as slightly harmful or moderately harmful. However, when phosmet was added to the 3% Samaritá Tradicional bait, the mortality was only 3.9% (class 1-harmless), similar to the toxicity observed for the Success 0.02 CB ready-to-use bait (0.24 g a.i. spinosad/l) (<5% mortality). Although toxic baits were formulated with spinosyn-based insecticides, all toxic bait formulations were classified as harmless or slightly harmful (<50% mortality) to D. areolatus, with the exception of 1.5% Ceratrap + spinetoram and 7% Sugarcane molasses + spinosad (≈ 60% mortality-moderately harmful). In addition, these formulations did not show sublethal effects in reducing the parasitism and emergence rate of the F1 generation of D. areolatus in A. fraterculus larvae. The results serve as a basis for the correct use of toxic food baits without affecting the biological control.

Biology and Fertility Life Tables for Palpita forficifera (Lepidoptera: Crambidae) Reared on Three Olive Cultivars and Privet.

Palpita forficifera Munroe, 1959 (Lepidoptera: Crambidae) is the main pest of the olive tree (Olea europaea L. Oleaceae) in Brazil. This study investigated the biology of P. forficifera reared on different hosts and elaborated the corresponding fertility life table for a better understanding of its development. Biology of P. forficifera was studied using olive cultivars Arbequina, Arbosana and Koroneiki and the alternative host privet (Ligustrum lucidum Ait., Oleaceae), under controlled conditions of temperature (25 ± 2°C), relative humidity (60 ± 10%), and photophase (14 h). We evaluated duration and viability of egg, larva, and pupa stages; number and duration of instars; sex ratio; pupa weight; duration of preoviposition, oviposition, and postoviposition periods; fecundity and longevity. The fertility life table was elaborated from these parameters. Larvae fed with privet had longer larval stage, and consequently, egg-pupa period. Larva viability was lower in cv. Arbosana, which reflected in lower viability in the egg-pupa period. Larvae fed with cv. Koroneiki originated females with higher fecundity. From the joint assessment of the biological parameters and the fertility life tables, cv. Koroneiki provided the greatest population increase, while cv. Arbosana impaired P. forficifera development. Thus, in areas of high occurrence of this species, cv. Arbosana should be considered as the more indicated cultivar for the establishment of new olive groves.

Moscas frugívoras e seus parasitoides nos municípios de Pelotas e Capão do Leão, Rio Grande do Sul, Brasil / Frugivorous flies and their parasitoids in the cities of Pelotas and Capão do Leão, Rio Grande do Sul, Brazil

As moscas frugívoras (Tephritoidea) são as principais pragas da fruticultura de clima temperado no Brasil. O objetivo do presente trabalho foi avaliar a infestação desses dípteros e a ocorrência de seus parasitoides em frutíferas nos municípios de Pelotas e Capão do Leão, localizados na região Sul, nas safras agrícolas de 2007/08 e 2008/09. Foram coletados frutos de araçazeiro-amarelo e vermelho (Psidium cattleianum Sabine, 1821), butiazeiro [Butia capitata (Mart.) Becc., 1916], caquizeiro (Diospyros kaki Linnaeus, 1753), cerejeira-do-mato (Eugenia involucrata DC., 1828), goiabeira [Psidium guajava (Linnaeus, 1753)], goiabeira-serrana [Acca sellowiana (Berg.) Burret, 1941], nespereira [Eriobotrya japonica (Thunb.) Lindley, 1822], pessegueiro [Prunus persicae (L.) Batsch, 1801], pitangueira (Eugenia uniflora Linnaeus,1753) e uvalheira (Eugenia pyriformis Cambessèdes, 1832). Os frutos foram coletados e transportados para o laboratório, onde foram individualizados e determinados os seguintes parâmetros: índice de infestação das moscas, índice de parasitismo e frequência de indivíduos por espécie de parasitoide. Foram constatadas duas espécies de Tephritidae, Anastrepha fraterculus (Wiedemann, 1830) (90,5 por cento) e Ceratitis capitata (Wiedemann, 1824) (9,5 por cento) e duas de Lonchaeidae, Neosilba zadolicha McAlpine & Steyskal, 1982 (87,8 por cento) e uma espécie ainda não descrita, referida como Neosilba n. sp. 3 (12,2 por cento). Anastrepha fraterculus é a espécie mais abundante nos dois municípios, sendo constatada na maioria das frutíferas coletadas. Caquizeiro e goiabeira foram os hospedeiros que apresentaram o maior índice de infestação por C. capitata. Quanto às espécies de Neosilba, a maior infestação ocorreu em frutos de goiabeira-serrana. Dos parasitoides emergidos, foram identificadas três espécies, sendo duas de Braconidae, Doryctobracon areolatus (Szépligeti, 1911) (52,6 por cento) e Opius bellus (Gahan, 1930) (27,5 por cento) e uma espécie de Figitidae, Aganaspis pelleranoi (Brèthes, 1924) (20,0 por cento). Doryctobracon areolatus foi o parasitoide mais frequente na maioria das frutíferas amostradas, com exceção da pitangueira e cerejeira-do-mato em que predominou O. bellus, e em pessegueiro com predomínio de A. pelleranoi.

Frugivorous flies (Tephritoidea) are the main pests in temperate-zone fruit crop in Brazil. The objective of this research is to evaluate the infestation of these flies and the incidence of their parasitoids in fruit trees from 2007/08 and 2008/9 crops in Pelotas and in Capão do Leão, located in the south of Rio Grande do Sul. Fruits were collected from yellow guava and red guava (Psidium cattleianum Sabine, 1821), pindo palm [Butia capitata (Mart.) Becc., 1916], persimmon (Diospyros kaki Linnaeus, 1753), wild cherry (Eugenia involucrata DC., 1828), guava [Psidium guajava (Linnaeus, 1753)], feijoa tree [Acca sellowiana (Berg.) Burret, 1941], medlar [Eriobotrya japonica (Thunb.) Lindley, 1822], peach [Prunus persicae (L.) Batsch, 1801], surinam cherry (Eugenia uniflora Linnaeus,1753) and (Eugenia pyriformis Cambessèdes, 1832). The fruit was collected and transported to the laboratory, where the following parameters were individually determined: fly infestation rate, parasitism rate, and its frequency per parasitoid specie. It was found two species of Tephritidae, Anastrepha fraterculus (Wiedemann, 1830) (90.5 percent) and Ceratitis capitata (Wiedemann, 1824) (9.5 percent) and two of Lonchaeidae, Neosilba zadolicha McAlpine & Steyskal, 1982 (87.8 percent) and a species not yet described, called Neosilba n. sp. 3 (12.2 percent). Anastrepha fraterculus is the most abundant species in the two cities and it was detected in most fruit crops collected. The persimmon and the guava were the hosts that showed the highest index of C. capitata infestation. Regarding to the species of Neosilba, the highest infestation occurred in fruits of feijoa tree. From the emerged parasitoids, it was identified three species two of Braconidae, Doryctobracon areolatus (Szépligeti, 1911) (52.6 percent) and Opius bellus (Gahan, 1930) (27.5 percent) and a species of Figitidae, Aganaspis pelleranoi (Brèthes, 1924) (20.0 percent). Doryctobracon areolatus was the most frequent parasitoid in most sampled fruit trees, except for surinam cherry and wild cherry, where O. bellus was predominant and for peach, A. pelleranoi.

Enraizamento de estacas herbáceas de mirtilo: influência da lesão na base e do ácido indolbutírico / Rooting of herbaceous blueberry cuttings: influence of the base incision and indolbutiric acid

O mirtilo (Vaccinium sp.) é uma espécie de clima temperado que, por ocasião do período vegetativo, produz abundante quantidade de material vegetal que pode ser utilizado na propagação. Objetivou-se verificar o potencial de enraizamento de estacas herbáceas de diferentes cultivares de mirtilo, tratadas ou não com ácido indolbutírico e com e sem lesão na base. O trabalho foi realizado em dois experimentos, testando a capacidade de enraizamento das cultivares Florida, Woodard, Bluegem, Bluebele, Clímax e Briteblue. No primeiro experimento, as estacas das cultivares foram tratadas com AIB (0, 2500, 5000 e 7500mgL-1). No segundo experimento utilizou-se 2000mgL-1 de AIB, em estacas com e sem lesão na base. O delineamento utilizado foi completamente casualizado com repetições e unidades experimentais adequadas para cada experimento. O uso do ácido indolbutírico e a lesão nas estacas, não proporcionaram estímulo na emissão de raízes adventícias; as cultivares apresentam potencial genético de enraizamento diferenciado, sendo que, a Bluebelle apresentou maiores porcentuais de estacas enraizadas, e a Clímax, os menores porcentuais.

Blueberries (Vaccinium sp.) are species of temperate climate that, for occasion of the vegetative period, produce large amount of vegetal material that can be used in the propagation. This way, with the aim of verifying the rooting potential of different herbaceous cuttings of blueberry cultivars, with the use or not of indolbutíric acid and base injury. The work was carried out in two experiments, having tested the capacity of rooting of the following cultivars Florida, Woodard, Bluegem, Bluebele, Clímax and Briteblue. In the first experiment, cuttings of cultivars were treated with IBA (0, 2500, 5000 and 7500mg.L-1). On the second experiment one used 2000mg.L-1 of AIB, in cuttings with and without injury in the base. The experimental design was the completely randomized with adjusted repetitions and experimental units for each experiment. After 90 days, it was evaluated rooting percentage for each cultivar submitted to IBA treatment with different doses. The use of the indolbutíric acid and the cutting injury, did not stimulated the emission of adventitious root; the cultivars present genetic potential of differentiated rooting, so that, the Bluebelle presented higher percentage rooting cutting, and the Climax, the lowest percentage.