Molecular identification for Helicoverpa spp. in Bt and non-Bt crops in central Argentina

O objetivo deste trabalho foi identificar, por análise molecular, as espécies do gênero Helicoverpa nas lavouras − Bt e não Bt − de milho, soja e alfafa, no centro da Argentina. Um total de 1.343 lagartas foram analisadas por PCR-RFLP. A espécie H. zea foi a única detectada no milho não Bt e na maioria do Bt. A espécie H. gelotopoeon predominou na soja não Bt e na alfafa, mas H. zea ocorreu em baixa proporção. A soja Bt não apresentou infestações por Helicoverpa spp. A exótica H. armigera não foi encontrada, porém, mariposas adultas dessa espécie foram capturadas com armadilha luminosa em uma amostragem complementar.The objective of this work was to identify, by molecular analysis, the species of the genus Helicoverpa in corn, soybean, and lucerne Bt and non‑Bt crops, in central Argentina. A total of 1,343 carterpillars were analyzed by PCR-RFLP. Helicoverpa zea was the only species detected on non-Bt and on most Bt corn hybrids. The species H. gelotopoeon predominated on non‑Bt soybean and on lucerne, and H. zea larvae occurred in low proportion. Bt soybean did not show Helicoverpa spp. infestations. The exotic H. armigera was not found, though adult moths of this species were light-trapped in a complementary sampling

Identificação molecular de Helicoverpa spp. em culturas Bt e não Bt no centro da Argentina

The objective of this work was to identify, by molecular analysis, the species of the genus Helicoverpa in corn, soybean, and lucerne Bt and non-Bt crops, in central Argentina. A total of 1,343 carterpillars were analyzed by PCR-RFLP. Helicoverpa zea was the only species detected on non-Bt and on most Bt corn hybrids. The species H. gelotopoeon predominated on non-Bt soybean and on lucerne, and H. zea larvae occurred in low proportion. Bt soybean did not show Helicoverpa spp. infestations. The exotic H. armigera was not found, though adult moths of this species were light-trapped in a complementary sampling.O objetivo deste trabalho foi identificar, por análise molecular, as espécies do gênero Helicoverpa nas lavouras – Bt e não Bt – de milho, soja e alfafa, no centro da Argentina. Um total de 1.343 lagartas foram analisadas por PCR-RFLP. A espécie H. zea foi a única detectada no milho não Bt e na maioria do Bt. A espécie H. gelotopoeon predominou na soja não Bt e na alfafa, mas H. zea ocorreu em baixa proporção. A soja Bt não apresentou infestações por Helicoverpa spp. A exótica H. armigera não foi encontrada, porém, mariposas adultas dessa espécie foram capturadas com armadilha luminosa em uma amostragem complementar.Instituto de Microbiología y Zoología Agrícola (IMYZA)Fil: Balbi, Emilia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Flores, Fernando Miguel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Tosto, Daniela Sandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arneodo Larochette, Joel Demian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Biologia e morfometria dos estágios imaturos de Epinotia aporema em dieta artificial

The objective of this work was to establish a life table for the immature stages of Epinotia aporema, as part of a wider investigation on its biological control. Insects were reared on an artificial diet at 25±1ºC and a 16:8 (light:dark) hour photoperiod. For the identification of larval instars for the study of pathogen-insect interactions under laboratory conditions, head capsule widths (HCWs) were also determined. The egg incubation period was 4.13±0.30 days, larval stage took 11.64±0.49 days, and the development time of the pupal phase was sex-dependent with 8.51±0.69 days for the females and 9.41±0.65 days for the males. Five larval instars were identified.O objetivo deste trabalho foi estabelecer uma tabela de vida para os estágios imaturos de Epinotia aporema, como parte de um estudo mais amplo para seu controle biológico. Os insetos foram criados em dieta artificial a 25±1ºC e 16:8 (luz:escuridão) horas de fotoperíodo. Para a identificação dos estágios larvais para estudos de interação inseto-patógeno em condições de laboratório, as larguras de cápsula cefálica também foram determinadas. O período de incubação dos ovos foi de 4,13±0,30 dias, o estágio larval foi de 11,64±0,49 dias, e o tempo de desenvolvimento das pupas dependeu do sexo, com 8,51±0,69 dias para as fêmeas e 9,41±0,65 dias para os machos. Foram identificados cinco estágios larvais

Potential of predatory neotropical ladybirds and minute pirate bug on strawberry aphid

Laboratory trials were performed to determine the impact of three Neotropical predatory coccinellids (Cycloneda sanguinea, Eriopis connexa and Coleomegilla quadrifasciata) and a minute pirate bug (Orius insidiosus) on Chaetosiphon fragaefolii, an important strawberry aphid pest. The predation on C. fragaefolii nymphs and adults, as well as the time to the first attack of all predators were compared with predation on Aphis gossypii. Predator preferences for prey and aphid defensive behavior were also evaluated. Moreover, the effect of coccinellids on C. fragaefolii population growth was assessed in experimental greenhouse conditions. The predation rate varied among predators, being significantly lower for O. insidiosus than for the coccinellids. Consumption was higher on A. gossypii than on C. fragaefolii, regardless of the aphids developmental stage. The time to the first attack of all predators was longer in the presence of C. fragaefolii. Walking away and cornicle secretion were the most common antipredator behaviors of aphid against coccinellids and O. insidiosus, respectively. Coccinellids preferred A. gossypii over C. fragaefolii, while O. insidiosus showed indifference. Cycloneda sanguinea and E. connexa exhibited the highest suppression effect on the growth rate of C. fragaefolii. Thus, the four predators evaluated could contribute to reduce strawberry aphid populations, especially C. sanguinea and E. connexa.Fil: Francesena, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Rocca, Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Rizzo, Maria Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Arneodo Larochette, Joel Demián. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Greco, Nancy Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires; Argentin

First report of chrysodeixis includens nucleopolyhedrovirus (ChinNPV) infecting chrysodeixis includens (Lepidoptera: Noctuidae) in Argentina

Summary Typical baculovirus infection symptoms were observed in Chrysodeixis includens Walker (Lepidoptera: Noctuidae) larvae from a laboratory rearing in Tucumán, Argentina. Scanning electron microscopy revealed the occurrence of polyhedral occlusion bodies displaying a heterogeneous morphology. Amplification, sequencing, and phylogenetic analysis of conserved polyhedrin, lef-8 and lef-9 genes identified the pathogen, for the first time in Argentina, as a variant of Chrysodeixis includens nucleopolyhedrovirus (ChinNPV). The biocontrol potential of this new isolate is worthy of future research.Fil: Arneodo Larochette, Joel Demián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Dami, Luciana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Tecnología Agroindustrial del Noroeste Argentino; ArgentinaFil: Jakubowicz, Violeta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Alzogaray, Raúl Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigaciones de Plagas E Insecticidas; ArgentinaFil: Taibo, Catalina Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentin

First identification of bacterial endosymbionts in three South-American spittlebug pests: Notozulia entreriana, Deois mourei and Deois knoblauchii

Spittlebugs cause major pasture damage in the Neotropics. As most xylem-feeders, they depend on microbial symbionts to supply essential amino acids to their diet. Here, the obligate nutritional endosymbiont ‘Candidatus Sulcia muelleri’ (Bacteroidetes) was detected in three main cercopid pests of South America: Notozulia entreriana (Berg), Deois (Deois) mourei Cavichioli et Sakakibara and Deois (Deois) knoblauchii (Berg) (Cercopidae Ishnorhininae). In all insect species, bacteriomes were located laterally in the abdomen, and ultrathin sections of N. entreriana bacteriocytes showed typical sulcia-like bacteria. PCR and sequencing of a 914-bp fragment of the bacterial 16S rRNA gene revealed 100% nucleotide identity among sulcia strains obtained from the three host species. These sequences were also identical to those previously obtained from two other New World spittlebugs of the same subfamily, providing evidence for host/symbiont coevolution. Microscopic and molecular analyses suggested that N. entreriana lacked additional symbionts (i. e. ‘Candidatus Zinderia insecticola’ or sodalis-like bacteria [Proteobacteria]) that often co-occur with sulcia within members of the superfamily Cercopoidea. Though amplicons were occasionally generated from D. (D.) mourei and D. (D.) knoblauchii with primers intended for zinderia, they failed to sequence. Further research is needed to elucidate the identity of bacteria other than sulcia in Deois spp.Instituto de Microbiología y Zoología Agrícola (IMYZA)Fil: Foieri, Alvaro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Microbiología y Zoología Agrícola; ArgentinaFil: Foieri, Alvaro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Decker Franco, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Microbiología y Zoología Agrícola; ArgentinaFil: Decker Franco, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Marino de Remes Lenicov, Ana Maria. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Arneodo Larochette, Joel Demian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Microbiología y Zoología Agrícola; ArgentinaFil: Arneodo Larochette, Joel Demian. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentin

Comparative Pathogenesis of Generalist AcMNPV and Specific RanuNPV in Larvae of Rachiplusia nu (Lepidoptera: Noctuidae) Following Single and Mixed Inoculations

The South American soybean pest, Rachiplusia nu (Guenée), is naturally infected by Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and Rachiplusia nu nucleopolyhedrovirus (RanuNPV). We compared their pathogenicity to fourth-instar R. nu larvae, by evaluating time to death and virus spread throughout the tissues in single and mixed infections. Bioassays showed that generalist AcMNPV had a faster speed of kill than specific RanuNPV, while the mixed-virus treatment did not statistically differ from AcMNPV alone. Histopathology evidenced similar tissue tropism for both viruses, but co-inoculation resulted in mostly AcMNPV-infected cells. In sequential inoculations, however, the first virus administered predominated over the second one. Implications on baculovirus interactions and biocontrol potential are discussed.Instituto de Microbiología y Zoología Agrícola (IMYZA)Fil: Decker Franco, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Decker Franco, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Taibo, Catalina Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigación en Ciencias Veterinarias y Agronómicas. Laboratorio Integral de Microscopía; ArgentinaFil: Di Rienzo, Julio A. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Estadística y Biometría; ArgentinaFil: Alfonso, Victoria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Alfonso, Victoria. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Arneodo, Joel D. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Arneodo, Joel D. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; Argentin

Characterization of a new <i>Helicoverpa armigera nucleopolyhedrovirus</i> variant causing epizootic on a previously unreported host, <i>Helicoverpa gelotopoeon</i> (Lepidoptera: Noctuidae)

This paper reports the first biological and molecular characterization of a nucleopolyhedrovirus isolated from the soybean and cotton pest Helicoverpa gelotopoeon. Studies were performed following a virus outbreak in a rearing facility and in wild H. gelotopoeon populations in Córdoba, Argentina. Host identity was corroborated by partial sequencing of the COI gene. Scanning electron microscope observations of purified OBs revealed their polyhedral morphology and an average diameter of 0.89 ± 0.14 μm. Ultrathin sections of infected larvae examined by transmission electron microscopy showed the intranuclear occurrence of polyhedra and virus particles in fat body cells. Nucleocapsids were singly enveloped. Phylogenetic analysis of lef-8, lef-9, polh, orf5/5b and hr3-orf62 viral sequences identified this new NPV isolate (hereafter HegeSNPV) as a variant of Helicoverpa armigera nucleopolyhedrovirus (HearNPV). Furthermore, HegeSNPV was closely related to the so-called “HzSNPV Group” within HearNPV, although having particular characteristics.Instituto de Biotecnologia y Biologia Molecula