1,543 research outputs found

    Immature stages of Spodoptera eridania (Lepidoptera: noctuidae): developmental parameters and host plants.

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    This study aimed to detail the temporal and morphological parameters of the immature stages of southern armyworm Spodoptera eridania (Stoll, 1782) with larvae feed on artificial diet, under controlled conditions (25?±?1°C, 70?±?10% relative humidity and 14-h photophase) and gather information about their larval host plants. The viability of the egg, larval, pupal, and prepupal stages was 97.82, 93.62, 96.42, and 97.03%, respectively. The average duration of the egg, larval, pupal, and pre-pupal stages was 4.00, 16.18, 1.58, and 9.17 d, respectively. During the larval stage, 43.44% of females passed through seven instars, observing that the female's development was significant slower than males. The female larvae that developed through six and seven instars exhibited a mean growth rate of 1.52 and 1.44, respectively. Female pupae were significantly larger, exhibiting faster development than males. The rearing method proved to be adequate, providing more detailed observations of the biological cycle, especially at the larval stage, and resulting in an overall survival of almost 85%. Two hundred two plant species belonging to 58 families are listed as natural hosts for S. eridania, mainly including Asteraceae, Fabaceae, Solanaceae, Poaceae, Amaranthaceae, and Malvaceae

    Rationality of quotients by linear actions of affine groups

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    Let G be the (special) affine group, semidirect product of SL_n and C^n. In this paper we study the representation theory of G and in particular the question of rationality for V/G where V is a generically free G-representation. We show that the answer to this question is positive if the dimension of V is sufficiently large and V is indecomposable. We have a more precise theorem if V is a two-step extension 0 -> S -> V -> Q -> 0 with S, Q completely reducible.Comment: 18 pages; dedicated to Fabrizio Catanese on the occasion of his 60th birthda

    Immature development of Spodoptera dolichos (Fabricius) (Lepidoptera: noctuidae).

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    We provide detailed temporal and morphological parameters of the immature stages of Spodoptera dolichos (Fabricius) larvae fed on artificial diet under controlled conditions (25?±?1°C, 70?±?10% RH, and 14 h photophase). The viability of the egg, larval, pupal, and prepupal stages was 97.5%, 97.0%, 93.1%, and 98.9%, respectively. The average duration of the egg, larval, prepupal, and pupal stages was 5.0, 23.4, 3.2, and 21.5 days, respectively. Females took longer at the larval stage than males, with 10.5% of them having seven instars. The growth rate of female larvae that developed through six and seven instars was 1.72 and 1.54, respectively. Female pupae were significantly larger, exhibiting slower development than males

    Efeito do tamanho e de mĂșltiplos casais sobre o potencial reprodutivo de Spodoptera eridania (Stoll, 1782) (Lepidoptera: Noctuidae).

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    Entre os lepidĂłpteros de importĂąncia agrĂ­cola, Spodoptera eridania (Stoll, 1782) tem despertado atenção por atingir nĂ­veis de dano econĂŽmico em culturas de importĂąncia como algodĂŁo e soja. Entretanto, existem poucos estudos detalhados de biologia, especialmente relacionados a aspectos reprodutivos. Visando determinar a capacidade mĂĄxima reprodutiva desta espĂ©cie avaliou-se o efeito do tamanho, empregando como parĂąmetro o peso pupal, e o nĂșmero de casais por gaiola (um e trĂȘs) sobre o nĂșmero de cĂłpulas, fecundidade e fertilidade. Os experimentos foram conduzidos em sala climatizada (25 ± 1ÂșC, 70 ± 10% UR e fotofase de 14 horas) com observaçÔes diĂĄrias. Adultos, emergidos no mesmo dia, classificados de acordo com a massa pupal, como pequenos, mĂ©dios e grandes foram dispostos em gaiolas plĂĄsticas, (10 x 15cm), alimentados com dieta artificial e ĂĄgua estĂ©ril. Foram formadas 15 gaiolas com um casal cada, todos de tamanho mĂ©dio, cinco gaiolas com 3 casais de tamanho pequeno e mĂ©dio e 4 com trĂȘs casais de tamanho grande. O nĂșmero mĂ©dio de cĂłpulas dos casais de tamanho mĂ©dio mantidos individualmente (1,13) foi significativamente menor do que o dos insetos pequenos (2,58), mĂ©dios (2,47) e grandes (2,33),mantidos a trĂȘs por gaiola. A fecundidade mĂ©dia dos casais individuais (1.398,00) tambĂ©m foi significativamente menor que a dos mantidos a trĂȘs por gaiola, tanto de tamanho pequeno (1.709,07), mĂ©dio (2.044,27) e grande (2.469,92). Entre estes Ășltimos observou-se efeito positivo entre o tamanho da pupa e a fecundidade, com diferenças significativas entre todos os tamanhos. A fertilidade mĂ©dia dos casais individuais (67,45) foi muito inferior a observada para os casais pequenos (97,32%), mĂ©dios (96,43%) e grandes (98,91%), mantidos a trĂȘs por gaiola. Estes resultados indicam que em estudos que estimam o potencial reprodutivo devem ser utilizados pelo menos trĂȘs casais por gaiola e que sejam descritos os pesos das pupas que originaram os adultos

    Parùmetros biológicos dos estågios imaturos de Spodoptera eridania (Stoll, 1782) (Lepidoptera: Noctuidae), em condiçÔes controladas.

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    O gĂȘnero Spodoptera (GuenĂ©e, 1852) Ă© cosmopolita e abriga grande parte das lagartas de importĂąncia agrĂ­cola. Spodoptera eridania (Stoll, 1782) Ă© uma espĂ©cie polĂ­faga que se alimenta de plantas de 57 famĂ­lias, incluindo muitas de importĂąncia econĂŽmica. Este estudo objetivou detalhar parĂąmetros biolĂłgicos de desenvolvimento dos estĂĄgios imaturos de S. eridania, em condiçÔes controladas (25 ± 1ÂșC, 70 ± 10% UR e fotofase de 14 horas). Foram avaliados 4.454 ovos provenientes de 16 posturas e 298 larvas neonatas, individualmente, alimentadas com dieta artificial modificada de Grenee et al. A viabilidade dos ovos, larvas, prĂ©-pupas e pupas foi de 97,82; 93,62; 96,42; 97,03%, com duração de 4,00; 16,18; 1,58 e 9,17 dias, respectivamente. Observou-se que 93% das fĂȘmeas e 100% dos machos passaram por seis e 7% das fĂȘmeas passaram por sete instares larvais. A partir do quinto Ă­nstar observou-se diferenciação no tamanho das cĂĄpsulas entre machos e fĂȘmeas de seis instares e, entre fĂȘmeas com as de sete instares, a diferenciação iniciou no quarto Ă­nstar, com razĂŁo de crescimento menor que as demais, no entanto o tamanho final foi maior que nas larvas de seis instares, compensado pelo Ă­nstar adicional. O tamanho final das cĂĄpsulas foi significativamente diferente entre fĂȘmeas (2,64mm) e machos (2,50mm), bem como entre as fĂȘmeas que passaram por seis (2,64mm) e sete Ă­nstares (2,72mm). Nas larvas femininas e masculinas de seis instares a razĂŁo mĂ©dia de crescimento foi de 1,52 e 1,51, respectivamente; nas de sete Ă­nstares foi de 1,44. As pupas femininas das larvas que passaram por seis instares foram significativamente maiores (377,53mg) do que os machos (329,45mg), porĂ©m, menores que as provenientes de larvas que passaram por sete Ă­nstares (435,11mg). Tanto a metodologia de criação quanto a dieta larval foram adequadas, pois permitiram 85,87% de sobrevivĂȘncia e um detalhamento muito maior das observaçÔes, especialmente, quando larvas

    Spodoptera frugiperda (Lepidoptera: Noctuidae) updated host plants and new records.

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    ConteĂșdo do volume 2: Ácaros; Biologia, fisiologia, morfologia; Controle biolĂłgico com bactĂ©rias entomopatogĂȘnicas; Controle biolĂłgico com fungos entomopatolĂłgicos; Controle biolĂłgico com nematoides; Controle biolĂłgico com parasitoides; Controle biolĂłgico com predadores; Ecologia e biodiversidade; Educação e etnoentomologia; Entomologia florestal; Entomologia Forense; Entomologia mĂ©dica e veterinĂĄria; Entomologia molecular; Manejo integrado de pragas; Organismos geneticamente modificados; Plantas inseticidas; Polinização; Pragas quarentenĂĄrias e invasivas; ResistĂȘncia de insetos a tĂĄticas de controle; ResistĂȘncia de plantas a insetos; SemioquĂ­micos e comportamento; SistemĂĄtica e taxonomia; Tecnologia de aplicação; Controle biolĂłgico com vĂ­rus entomopatogĂȘnicos; Controle quĂ­mico

    Revisiting the Zingiberales: Using Multiplexed Exon Capture to Resolve Ancient and Recent Phylogenetic Splits in a Charismatic Plant Lineage

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    The Zingiberales are an iconic order of monocotyledonous plants comprising eight families with distinctive and diverse floral morphologies and representing an important ecological element of tropical and subtropical forests. While the eight families are demonstrated to be monophyletic, phylogenetic relationships among these families remain unresolved. Neither combined morphological and molecular studies nor recent attempts to resolve family relationships using sequence data from whole plastomes has resulted in a well-supported, family-level phylogenetic hypothesis of relationships. Here we approach this challenge by leveraging the complete genome of one member of the order, Musa acuminata, together with transcriptome information from each of the other seven families to design a set of nuclear loci that can be enriched from highly divergent taxa with a single array-based capture of indexed genomic DNA. A total of 494 exons from 418 nuclear genes were captured for 53 ingroup taxa. The entire plastid genome was also captured for the same 53 taxa. Of the total genes captured, 308 nuclear and 68 plastid genes were used for phylogenetic estimation. The concatenated plastid and nuclear dataset supports the position of Musaceae as sister to the remaining seven families. Moreover, the combined dataset recovers known intra- and inter-family phylogenetic relationships with generally high bootstrap support. This is a flexible and cost effective method that gives the broader plant biology community a tool for generating phylogenomic scale sequence data in non-model systems at varying evolutionary depths

    Generalized Involution Models for Wreath Products

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    We prove that if a finite group HH has a generalized involution model, as defined by Bump and Ginzburg, then the wreath product H≀SnH \wr S_n also has a generalized involution model. This extends the work of Baddeley concerning involution models for wreath products. As an application, we construct a Gelfand model for wreath products of the form A≀SnA \wr S_n with AA abelian, and give an alternate proof of a recent result due to Adin, Postnikov, and Roichman describing a particularly elegant Gelfand model for the wreath product \ZZ_r \wr S_n. We conclude by discussing some notable properties of this representation and its decomposition into irreducible constituents, proving a conjecture of Adin, Roichman, and Postnikov's.Comment: 29 page

    Coulomb Blockade in low mobility nanometer size Si:MOSFETs

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    We investigate coherent transport in Si:MOSFETs with nominal gate lengths 50 to 100nm and various widths at very low temperature. Independent of the geometry, localized states appear when G=e^{2}/h and transport is dominated by resonant tunnelling through a single quantum dot formed by an impurity potential. We find that the typical size of the relevant impurity quantum dot is comparable to the channel length and that the periodicity of the observed Coulomb blockade oscillations is roughly inversely proportional to the channel length. The spectrum of resonances and the nonlinear I-V curves allow to measure the charging energy and the mean level energy spacing for electrons in the localized state. Furthermore, we find that in the dielectric regime, the variance var(lng) of the logarithmic conductance lng is proportional to its average value consistent with one-electron scaling models.Comment: 4 pages, 4 figure
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