ABSTRACT During the 2021/2022 soybean production season in Itapúa, Paraguay, the presence of Etiella zinckenella (Treitschke) caterpillars affecting soybean pods in the country was documented. The observations were made amidst a widespread drought that adversely affected soybean production. Caterpillars were collected from pods that exhibited signs of pest entry. Morphological characterization of the collected specimens matched the descriptions provided in taxonomic keys for E. zinckenella larvae. Molecular identification through DNA extraction and sequencing confirmed the identity of the pest as E. zinckenella, exhibiting a 96% similarity with known accessions of the species in the GenBank database. As a challenging pest to control, efforts should be directed towards evaluating the economic and damage thresholds caused by E. zinckenella, assessing resistance in soybean varieties used in Paraguay, and investigating the efficacy of biological and chemical insecticides. These findings can contribute to the development of integrated management strategies for effectively mitigating the impact of this pest on soybean production in Paraguay.

RESUMEN Durante la temporada de producción de soja 2021/2022 en la región de Itapúa, Paraguay, se documentó la presencia de orugas Etiella zinckenella (Treitschke) afectando las vainas de soja en el país. Las observaciones se realizaron en medio de una sequía generalizada que afectó negativamente a la producción de soja. Las orugas se recolectaron de las vainas que mostraban signos de entrada de plagas. La caracterización morfológica de los especímenes recolectados coincidió con las descripciones proporcionadas en claves taxonómicas para las larvas de E. zinckenella. La identificación molecular a través de la extracción y secuenciación de ADN confirmó la identidad de la plaga como E. zinckenella, exhibiendo un 96% de similitud con las accesiones conocidas de la especie en la base de datos GenBank. Como plaga difícil de controlar, los siguientes esfuerzos deben dirigirse a evaluar los umbrales económicos y de daño causados por E. zinckenella, evaluar la resistencia en las variedades de soja utilizadas en Paraguay e investigar la eficacia de los insecticidas biológicos y químicos. Estos hallazgos pueden contribuir al desarrollo de estrategias de manejo integrado para mitigar de manera efectiva el impacto de esta plaga en la producción de soja en Paraguay.

ABSTRACT Etiella zinckenella is a cosmopolitan pest of worldwide distribution that mainly attacks species of the Fabaceae family, particularly soybean as it is considered the main host for the insect. The larvae enter the pods and feed on the seeds, producing feces that accumulate and cause seed loss. In Chile, E. zinckenella has been reported in the Metropolitan Region, but there is no information about the host in which it was detected. During the period February-March 2019, populations of native Alstroemeria spp. (A. angustifolia, A. cummingiana and A. marticorenae) were surveyed in the sector of Rodelillo Alto, Viña del Mar, and fruits were collected in order to identify the causal agent of perforations detected in them. In the capsules collected, the presence of E. zinckenella larvae feeding on the seeds was recorded. The determination of the insect at the species level was carried out with a morphological analysis of the larvae, confirmed through observation of the genitalia of adult females and males during rearing. This study is the first report on detection and identification of E. zinckenella in native Alstroemerias populations in Chile.

RESUMEN Etiella zinckenella es una plaga cosmopolita de distribución mundial que ataca principalmente a especies de la familia Fabaceae, considerándose la soya como su principal hospedero. La larva del insecto ingresa a las vainas y se alimenta de las semillas, produciendo fecas que se acumulan y generan la pérdida de las semillas. En Chile, se ha reportado la presencia de E. zinckenella en la Región Metropolitana, sin especificar el hospedero en el cual se detectó. Durante el período febrero-marzo de 2019, se prospectaron poblaciones de Alstroemeria spp. nativas (A. angustifolia, A. cummingiana y A. marticorenae) en el sector de Rodelillo Alto, Viña del Mar, para la colecta de frutos con la finalidad de identificar el agente causal de perforaciones detectadas en éstos. En las cápsulas recolectadas se registró la presencia de larvas de E. zinckenella alimentándose de las semillas. La determinación del insecto a nivel de especie se realizó con un análisis morfológico de las larvas, ratificado a través de la observación de genitalias de hembras y machos adultos obtenidos en crianza. En este estudio se documenta la primera detección e identificación de E. zinckenella en poblaciones de Alstroemerias nativas en Chile.

This work was carried out to quantify the damage caused by Etiella zinckenella (Treitschke) (Lepidoptera: Pyralidae) to common bean (Phaseolus vulgaris L.) cv. Pyatã, Guapo Brilhante, Iraí and Feijão-Verde in Pelotas, Canguçu and Arroio do Padre in the state of Rio Grande do Sul, in 1996/97 season. Samples of mature bean plants were harvested and thrashed in the laboratory and healthy grains were separated from damaged ones. Damaged grain percentage ranged from 15.5 (cv. Pyatã, in Arroio do Padre) to 44.0% (cv. Pyatã, in Canguçu).

Este trabalho objetivou o estudo dos componentes de produção na cultura do feijoeiro (Phaseolus vulgaris L.), quando se utilizaram os inseticidas sistêmicos Aldicarb 150 G (6 kg/ha) e Fosthiazate 100 G (10, 20, 30 e 40 kg/ha), além da testemunha. A pesquisa foi desenvolvida na Universidade Federal de Viçosa, Viçosa (MG), em abril-julho de 1994. O delineamento experimental foi em blocos casualizados com quatro repetições, sendo a unidade experimental constituída de 500 plantas. Avaliaram-se altura das plantas, número de nós, mortalidade de plantas, número de flores, vagens, óvulos e grãos danificados (identificando-se os causadores dos danos). Foi estimada a produtividade média de cada tratamento, as perdas ocorridas e suas causas. A partir desses dados, confeccionou-se tabela de vida para a cultura. Não se verificou efeito dos inseticidas Aldicarb e Fosthiazate quanto à altura e ao número de nós das plantas de feijoeiro. O componente de produção que mais sofreu perdas foi a vagem devido ao ataque de Etiella zinckenella (Treitschke) (Lepidoptera: Pyralidae)] seguido da mortalidade de plantas na fase vegetativa e grãos (pelo ataque do fungo Colletotrichum lindemuthianum). A flutuação de perdas totais foi mais influenciada pela mortalidade de plantas seguida pelo abortamento de flores. Ocorreu menor mortalidade de plantas na fase vegetativa com o aumento na dosagem de Fosthiazate.

The main purpose of this research work carried out in 1994 at the Federal University of Viçosa, State of Minas Gerais, Brazil, was to determine the effects of systemic insecticides on several common bean (Phaseolus vulgaris L.) yielding components. Life tables have been developed based on mortality rates as well as the effects of soil application of systemic insecticides on several traits (plant height and plant mortality; nodule, flower and bean average numbers; percentage of damaged grains). Aldicarb 150 G and Phostiazate revealed no significant effects on plant height and average nodule number. The highest damage levels were recorded in beans - infestation by Etiella zinckenella (Treitschke) (Lepidoptera: Pyralidae); due to high plant mortality rates during the vegetative period and to grain losses (caused by Colletotrichum lindemuthianum). Total damage was primarily due to flower abortion.