RESUMO: A drosófila-da-asa-manchada, Drosophila suzukii Matsumura, é considerada o principal inseto-praga de pequenos frutos no mundo. A identificação de hospedeiros suscetíveis é essencial para o desenvolvimento de estratégias de manejo. O objetivo deste estudo foi verificar o nível de infestação de D. suzukii em frutos de amoreira-preta, mirtileiro, morangueiro, araçazeiro e pitangueira cultivados na região no sul do Brasil e determinar os índices de infestação (II) por fruto. Os estudos foram realizados durante duas safras (2015/16 e 2016/17) em três áreas com cultivo orgânico de pequenas frutas. O maior nível de infestação natural de D. suzukii foi observado em amora-preta (40 a 65% de infestação) e morango (aproximadamente 30% de infestação). Em contraste, o mirtilo foi menos preferido (< 7% de infestação). Para as frutas nativas da região (araçá e pitanga), também ocorreu infestação da mosca, demonstrando serem hospedeiros potenciais para a multiplicação da praga nos períodos de entressafras. Em relação ao II, amoras e pitangas proporcionaram um maior número médio de insetos por grama de fruto (≈ 1,6 adultos de D. suzukii). Por outro lado, mirtilos e araçás apresentaram a menor relação de insetos emergidos por gramas de frutos (≈ 0,7 adultos por grama). O período entre final da primavera até meados do outono foi considerado ideal para a ocorrência da praga no campo. O conhecimento dos níveis de infestação natural é fundamental para o entendimento do comportamento da praga no campo, o que auxiliará no delineamento de estratégias de manejo.

ABSTRACT: The spotted-wing drosophila, Drosophila suzukii Matsumura, is considered the main insect pest of small fruit in the world. Identifying susceptible hosts is essential to develop management strategies. The aim of this study was to verify the level of D. suzukii infestation in blackberry, blueberry, strawberry, cattley guava and Surinam cherry fruits cultivated in the southern region in Brazil, and to determine the infestation index (II) per fruit. The studies were carried out during two harvests (2015/16 and 2016/17) in three areas with organic cultivation of small fruit. The highest level of D. suzukii natural infestation was observed in blackberry (40 to 65% infestation), and strawberry (approximately 30% infestation) fruits. In contrast, blueberries were less preferred (< 7% infestation). For native fruit of the region (cattley guava and Surinam cherry), it was also verified infestation of the fly, demonstrating they are hosts for multiplication in the off-season periods of the other crops. In relation to II, blackberry and Surinam cherry provided a higher average number of insects per gram of fruit (≈ 1.6 adults of D. suzukii). In contrast, blueberries and cattley guava had the lowest insect ratio per gram of fruit (≈ 0.7 adults per gram). The period between late spring to mid-autumn was considered ideal for the pest occurrence in the field. The knowledge of natural infestation levels is essential for understanding the behavior of the pest in the field, which will assist in the design of management strategies.

Abstract: Drosophila suzukii is one of the main pests of small fruits in the world. An effective monitoring is fundamental to detect the presence of the fly and to predict the infestation of fruits in new areas. We evaluated the food baits Ceratrap®, Torula®, Biofruit®, Suzukii Trap®, apple cider vinegar, and a homemade mixture comprising wine, vinegar and molasses (WVM) for D. suzukii attractiveness, and if reproductive stage affects females attraction and capture in the different baits. Bait selectivity of non-target insects was assessed. The preference of adults between ripe blackberry fruit and the food baits was also evaluated. Adults showed a higher attraction (61.97% of the captured insects) to the WVM mixture than to Ceratrap® (1.32%), Torula® (0.52%), Biofruit® (13.15%), Suzukii Trap® (17.6%), and apple vinegar (5.4%). Considering the attractiveness to D. suzukii, Suzukii Trap® and apple vinegar were the most selective to non-target insects. In general, reproductively immature females showed a preference for Biofruit®, apple vinegar, and WVM, whereas mature females did not show bait preferences. Adults preferred ripe blackberry fruit over the WVM mixture. Understanding the field behavior of D. suzukii is of foremost importance to estimate insect population density and outline pest management strategies.

Resumen Drosophila suzukii (Diptera, Drosophilidae) es una especie exótica, endémica del Asia y actualmente considerada plaga de pequeños frutos y frutas con hueso en varios países de Norteamérica y Europa. En 2013 fue detectada por primera vez en América del Sur, en el sur de Brasil. A diferencia de la mayoría de drosofílidos, esta especie merece mucha atención debido a que las hembras son capaces ovipositar dentro de frutos sanos, tornando imposible su comercialización y exportación. A pesar que la presencia de esta especie ya fue confirmada en diferentes estados de Brasil, aún no alcanza la condición de plaga. Sin embargo, la simple presencia de esta especie provoca preocupación a los productores de pequeños frutos y justifica la investigación de métodos de control, especialmente el control químico, el cual ayudaría a los fruticultores en caso que el insecto se torne una plaga. Con estos antecedentes, el objetivo de este trabajo fue evaluar, en laboratorio, el efecto ovicida y la mortalidad de adultos D. suzukii a diferentes insecticidas registrados para especies de la familia Tephritidae y Agromyzidae en varios cultivos. Los insecticidas deltametrina, dimetoato, spinosad, fenitrotion, fosmet, malatión, metidation y zeta-cipermetrina provocaron 100 % de mortalidad de adultos tres días después de la aplicación (DDA). Se constató que los insecticidas fenitrotion, malatión y metidation inviabilizaron 100 % de los huevos, seguidos por fosmet y diflubenzuron, que causaron una considerable reducción de eclosión de larvas dos DDA.

Abstract Drosophila suzukii (Diptera, Drosophilidae) is an exotic species, endemic to Asia and currently a pest to small and stone fruits in several countries of North America and Europe. It was detected in 2013 for the first time in South America, in the south of Brazil. Unlike most drosophilids, this species deserves special attention, because the females are capable of oviposit inside healthy fruits, rendering their sale and export prohibited. Despite the confirmed existence of this species in different states of Brazil, this insect is yet been to be given the pest status. Nevertheless, the mere presence of this species is enough to cause concern to producers of small fruits and to justify further investigation for it’s control, especially chemical control for a possible change in status. Therefore, the goal of this work was to evaluate, in laboratory, mortality of D. suzukii adults and ovicidal effect when exposed to different insecticides registered for species of the Tephritidae and Agromyzidae families in different cultures. The insecticides deltamethrin, dimethoate, spinosad, fenitrothion, phosmet, malathion, methidathion, and zeta-cypermethrin resulted in mortality to 100 % of the subjects three days after the treatment (DAT). Regarding the effects over eggs, it was established that the insecticides fenitrothion, malathion, and methidathion deemed 100 % of the eggs not viable, followed by phosmet and diflubenzuron, which also caused elevated reduction in the eclosion of larvae two DAT.

RESUMO O objetivo deste trabalho foi contribuir para o conhecimento da assembleia de besouros Scolytinae associada a plantios de eucalipto no sul do Estado do Rio Grande do Sul, Brasil e determinar espécies de importância à cultura. Amostras quinzenais foram retiradas de cinco fazendas da Fibria Celulose S/A, florestadas com Eucalyptus spp., no período de fevereiro de 2006 a dezembro de 2010, com armadilhas de interceptação de voo iscadas com etanol a 95%. Foram coletados 7.365 exemplares em 76 espécies, 18 gêneros e sete tribos. Corthylini, representada pelos gêneros Corthylus, Monarthum, Amphicranus, Metacorthylus, Microcorthylus e Tricolus e Xyleborini, por Ambrosiodmus, Dryocoetoides, Xyleborinus, Xyleborus e Xylosandrus foram as tribos mais representativas, com 42,1% e 31,6% espécies, respectivamente. Xylosandrus retusus e Xyleborinus saxeseni foram as espécies mais abundantes com 52,64% e 27,98% do total de espécimes amostradas, seguida por Corthylus antennarius, com 4,15% besouros coletados. Quinze espécies foram comuns a todos os locais, incluindo Xyleborus ferrugineus, considerada praga desta cultura, enquanto 25 espécies foram encontradas exclusivamente em apenas um local. A fazenda Cerro Alegre apresentou a maior riqueza de espécies e maior quantidade de espécies exclusivas; São Manoel demonstrou o maior índice de diversidade e equitabilidade; Aroeira teve a maior frequência de Scolytinae e São Francisco evidenciou a maior abundância e dominância. O estudo das assembleias de Scolytinae evidenciou o predomínio das espécies Xylosandrus retusus e Xyleborinus saxeseni em todos os ambientes estudados.

ABSTRACT The aim of this study was to contribute to the knowledge of the assembly of Scolytinae beetles associated with Eucalyptus plantations in southern Rio Grande do Sul state, Brazil, and determine species of importance to the culture. Biweekly samples were taken from five Fibria Celulose S/A farms forested with Eucalyptus spp., from February 2006 to December 2010, with flight intercept traps baited with 95% ethanol. We collected 7,365 specimens within 76 species, 18 genera, and seven tribes. Corthylini, represented by the genera Corthylus, Monarthum, Amphicranus, Metacorthylus, Microcorthylusand Tricolus, and Xyleborini, by Ambrosiodmus, Dryocoetoides, Xyleborinus, Xyleborus and Xylosandrus, were the most representative tribes, with 42.1% and 31.6% species, respectively. Xylosandrus retusus (Eichhoff) and Xyleborinus saxeseni (Ratzeburg) were the most abundant species, with 52.64% and 27.98% of all specimens sampled, followed by Corthylus antennarius Schedl with 4.15% beetles collected. Fifteen species were common to all sites, including Xyleborus ferrugineus (Fabricius), considered a potential pest to the culture, while 25 species were found exclusively in only one site. The farm Cerro Alegre had the highest species richness and larger number of exclusive species; São Manoel farm presented the highest diversity index and equitability; Aroeira farm had the highest frequency of Scolytinae and São Francisco farm showed the greatest abundance and dominance. The study of Scolytinae assemblages showed the predominance of Xylosandrus retusus and Xyleborinus saxeseni in all studied environmentals.