Effects of overexpressing individual lignin biosynthetic enzymes on feeding and growth of corn earworms (Helicoverpa zea) and fall armyworms (Spodoptera frugiperda)

2016 ◽  
Author(s):  
Patrick Dowd
Keyword(s):  
Spodoptera Frugiperda ◽  
Helicoverpa Zea ◽  
Biosynthetic Enzymes

Behavioral Interactions Between the Hyperparasitoid Mesochorus discitergus (Hymenoptera: Ichneumonidae) and Four Species of Noctuid Caterpillars: Evasive Tactics and Capture Efficiency

1994 ◽  
Vol 29 (3) ◽  
pp. 420-427 ◽  
Author(s):  
M. E. Baur ◽  
K. V. Yeargan
Keyword(s):  
Spodoptera Frugiperda ◽  
Helicoverpa Zea ◽  
Fall Armyworm ◽  
Corn Earworm ◽  
Fourth Instar ◽  
Capture Efficiency ◽  
Behavioral Interactions ◽  
Lepidopteran Larvae ◽  
Noctuid Species ◽  
Soybean Looper

The hyperparasitoid, Mesochorus discitergus (Say), oviposits into larvae of primary parasitoids while the latter are developing inside various lepidopteran hosts. To accomplish hyperparasitism, M. discitergus must capture the lepidopteran larvae. We studied the evasive behaviors of 2nd-, 3rd-, and 4th instar Helicoverpa zea (Boddie) (corn earworm), Pseudoplusia includens (Walker) (soybean looper), Spodoptera frugiperda (J. E. Smith) (fall armyworm), and 2nd- and 4th-instar Plathypena scabra (Fabricius) (green cloverworm), as well as the effectiveness of these tactics in eluding capture by M. discitergus females. Most individuals of all instars of corn earworm and fall armyworm made minimal efforts to escape. Although not commonly used by corn earworm and fall armyworm, their occasional vigorous responses were effective in deterring M. discitergus females. Dropping from a leaf, either unattached or attached by a thread, was also effective for preventing capture of those two noctuid species. Soybean loopers and green cloverworms responded much more actively. Second-instars of both species dropped off the leaf on a thread, while 3rd- and 4th-instar soybean loopers commonly used vigorous responses. Fourth-instar green cloverworms used vigorous responses and dropping off the leaf. Overall, 68% of the caterpillars using the vigorous response were captured, while 39% of those dropping on a thread and about 26% of those dropping off a leaf, unattached by a thread, were captured. Green cloverworms and soybean loopers were more difficult to capture than corn earworms and fall armyworms.

INFESTAÇÃO DE MILHO CRIOULO, CONVENCIONAL E TRANSGÊNICO PELA LAGARTA-DO-CARTUCHO E PELA LAGARTA-DA-ESPIGA E PARASITISMO DE OVOS

2017 ◽  
Vol 16 (3) ◽  
pp. 351
Author(s):  
CAMILA CORRÊA VARGAS ◽  
ROSANA MATOS DE MORAIS ◽  
LUIZA RODRIGUES REDAELLI
Keyword(s):  
Zea Mays ◽  
Spodoptera Frugiperda ◽  
Helicoverpa Zea ◽  
Genetically Modified ◽  
Fall Armyworm ◽  
Corn Earworm ◽  
Trichogramma Pretiosum ◽  
Hybrid Corn ◽  
Egg Parasitism ◽  
Santa Maria

RESUMO - O objetivo foi avaliar a infestação, o parasitismo de ovos e danos da lagarta-do-cartucho, Spodoptera frugiperda (J. E. Smith), e da lagarta-da-espiga, Helicoverpa zea (Boddie), em cultivares de milho: variedade crioulo (Lombo Baio), híbrido convencional (Semilha S395) e híbrido geneticamente modificado (Bt) (TC1507 Herculex I ®, Cry1F). O experimento foi conduzido em Santa Maria-RS, no período de segunda safra de 2014. O delineamento foi de blocos ao acaso, com três tratamentos e quatro repetições. Foram registrados os danos, o número de lagartas, de posturas e o parasitismo em ovos da lagarta-do-cartucho, dos 9 aos 72 dias após a emergência das plantas (DAE). A infestação da lagarta-da-espiga e o parasitismo de ovos foram registrados dos 67 aos 101 DAE. Os danos causados pela lagarta-do-cartucho foram semelhantes entre milho crioulo e convencional, os quais foram mais elevados do que no milho geneticamente modificado Bt. O número médio de lagartas-do-cartucho foi maior em milho crioulo. A média do número total de lagartas-da-espiga foi semelhante entre milho crioulo e convencional e superior à do Bt. Foi registrado o parasitismo de ovos para a lagarta-da-espiga por Trichogramma pretiosum Riley, nas três cultivares avaliadas, com porcentagens semelhantes entre milho crioulo e convencional e superior em milho Bt. Palavras-chave: Spodoptera frugiperda, Helicoverpa zea, Trichogramma pretiosum, Zea mays, manejo de pragas. INFESTATION IN INLANDRACE, CONVENTIONAL AND TRANSGENIC CORN BY FALL ARMYWORM AND CORN EARWORM, AND EGG PARASITISM  ABSTRACT - The objective of the work was to estimate the infestation and eggs parasitism of fall armyworm (J. E. Smith) and corn earworm (Boddie), in three corn varieties: landrace (LomboBaio), conventional hybrid (Semilha S395) and genetically modified hybrid (Bt) (TC1507 Herculex I ®, Cry1F). The experiment was carried out in Santa Maria-RS, during the second-season corn crop, in 2014. The experimental design was a completely randomized block with three treatments, and four replicates. We evaluated the damages, number of larvae, number of eggs and fall armyworm egg parasitism from 9 to 72 days after emergence (DAE). The infestation of corn earworm and the eggs parasitism were measured from 67 to 101 DAE. Fall armyworm damage was similar between landrace and conventional hybrid, and both higher than those of genetically modified hybrid Bt. Average number of fall armyworm larvae was higher in landrace cultivar. The average of total number of corn earworm larvae was similar on landrace and conventional hybrid, both higher than Bt hybrid. Corn earworm eggs parasitism by Trichogramma pretiosum Riley was recorded in the three evaluated cultivars and similar parasitism percentage was observed between landrace and conventional hybrid, which was higher in Bt maize. Keywords: Spodoptera frugiperda, Helicoverpa zea, Trichogramma pretiosum, Zea mays, pest management.

scholarly journals Uso de enemigos naturales y biorracionales para el control de plagas de maíz

Ra Ximhai ◽  
2012 ◽  
pp. 57-70 ◽  
Author(s):  
Cipriano García-Gutiérrez ◽  
María Berenice González-Maldonado ◽  
Edgardo Cortez-Mondaca
Keyword(s):  
Bacillus Thuringiensis ◽  
Spodoptera Frugiperda ◽  
Helicoverpa Zea ◽  
Frankliniella Occidentalis ◽  
Heterorhabditis Bacteriophora ◽  
Agrotis Ipsilon ◽  
Nomuraea Rileyi ◽  
Isaria Fumosorosea

Se presenta un análisis general del uso potencial de los enemigos naturales e insecticidas biorracionales para el control de las principales plagas del maíz en el Estado de Sinaloa. Se discute también sobre su composición, dosis, toxicidad y su efecto colateral en organismos benéficos (enemigos naturales y polinizadores). El trabajo revelo que es posible implementar el uso de los siguientes enemigos naturales y productos: Para en el control de larvas neonatas del gusano cogollero Spodoptera frugiperda (J. E Smith) con Nomuraea rileyi (Farlow) Samson; contra trips Frankliniella occidentalis (Pergande) con los nematodos Steinernema riobravis (Cabanillas y Poinar), S. feltiae (Filipjev) y Heterorhabditis bacteriophora (Poinar) a dosis de 10,000 IJ (4x10~IJ/m2 ); contra la mosca de los estigmas Euxesta stigmatias (Loew), fomentando el parasitismo natural de Spalangia sp., mientras que para el gusano trozador Agrotis ipsilon (Hufnagel) utilizando spinosad (concentrado soluble) a dosis de 0.123 kg de i. a; y para el gusano elotero Helicoverpa zea (Boddie) usando el análogo de la hormona de la muda metoxifenocida (24%) o 144 mg de i. a/L. Los agentes de control y biorracionales que no afectan de manera importante a los enemigos naturales son: El virus de la nucleopoliedrosis SfMNPV y SeMNPV; N. rileyi e Isaria fumosorosea (Wize); Bacillus thuringiensis (Berlinier); parasitoides y la azaridactina (nim). En el caso de los productos de síntesis química: El spinosad, oxymatrine y bifentrina, a pesar de presentar altos porcentajes de mortalidad en el control de plagas en maíz, se consideran de alto y moderado riesgo por ser tóxicos a abejas Aphis mellifera (L.), la metoxifenocida es relativamente poco tóxica para enemigos naturales. En general, los productos biorracionales tienen efecto de repelencia en larvas y adultos de estos insectos, inhiben la alimentación e inducen la muda, causan malformaciones e impiden el desarrollo y crecimiento, interfieren en la comunicación sexual reduciendo la cópula y oviposición, y provocan esterilidad en adultos, por lo que también podrían constituir un riesgo para los organismos benéficos. No obstante, se concluye que estos productos son menos tóxicos que los insecticidas químicos para los organismos no blanco, por lo que eventualmente también pueden ser usados con menor riesgo de contaminación ambiental en el control de plagas de maíz en la región agrícola del Norte de Sinaloa.

scholarly journals ACTION SPECTRUM OF Baculovirus spodoptera ON LEPIDOPTERA PESTS

2017 ◽  
Vol 16 (1) ◽  
pp. 52
Author(s):  
CAMILA DA SILVA FERNANDES SOUZA ◽  
FERNANDO HERCOS VALICENTE ◽  
MARCOS ANTÔNIO MATIELLO FADINI ◽  
RICARDO ANTÔNIO POLANCZYK
Keyword(s):  
Spodoptera Frugiperda ◽  
Sugar Cane ◽  
Helicoverpa Zea ◽  
First Generation ◽  
Action Spectrum ◽  
Fall Armyworm ◽  
Corn Earworm ◽  
Corn Borer ◽  
Egg Masses ◽  
Diatraea Saccharalis

ABSTRACT - This work evaluated the spectrum of action of Baculovirus spodoptera (SfMNVP) - 6NR on the fall armyworm Spodoptera frugiperda, corn earworm Helicoverpa zea and the sugar cane borer Diatraea saccharalis, species of economic importance in maize. For the bioassays, corn leaves immersed in a baculovirus suspension were used for baculovirus inoculation in fall armyworm and earworm and pieces of sugar cane for the corn borer. The foods were immersed in viral solutions of different baculovirus concentrations determined in a Neubauer chamber. The control only distilled water was used instead of the baculovirus suspension. The larvae fed for 48 hours and were then transferred to an artificial diet, without the baculovirus. After evaluating mortality, the development of the offspring (F1) was accompanied, evaluating the parameters: mortality, pupation and the number of egg masses in the first generation. The baculovirus was specific to fall armyworm and innocuous to earworm and the corn borer in the first generation. In the second generation, baculovirus was innocuous for all three species. The percentage of pupation showed an inverse relation with mortality for the three species in two generations. The number of egg masses in F1 was lower in S. frugiperda, did not change for D. saccharalis and higher in H. zea.Keywords: Helicoverpa zea, Spodoptera frugiperda, Diatraea saccharalis, entomopathogenie virus.ESPECTRO DE AÇÃO DE Baculovirus spodoptera A LEPIDÓPTEROS PRAGARESUMO - Neste trabalho foi avaliado o espectro de ação do Baculovirus spodoptera (SfMNVP) - 6NR à lagarta-do-cartucho Spodoptera frugiperda, à lagarta-da-espiga Helicoverpa zea e à broca-da-milho Diatraea saccharalis, espécies de importância econômica na cultura do milho. Para a realização dos bioensaios foram utilizadas folhas de milho imersas em suspensão com o baculovírus em concentrações determinadas em câmara de Neubauer, para lagarta-do-cartucho e para lagarta-da-espiga. Para broca-do-milho o substrato utilizado foi colmo de cana-de-açúcar. Na testemunha foi utilizada somente água destilada ao invés da suspensão com o baculovírus. As lagartas se alimentaram por 48 horas, após este período, foram transferidas para dieta artificial sem o bacilovírus. Após a avaliação da mortalidade,odesenvolvimento da prole (F1) foi acompanhado sendo avaliados os parâmetros: mortalidade, pupação e o número de massas de ovos na primeira geração. O baculovírus foi especifico para lagarta-do-cartucho e inócuo tanto para lagarta-da-espiga quanto para broca-do-milho na primeira geração. Na segunda geração, o baculovírus foi inócuo para as três espécies. A porcentagem de pupação apresentou relação inversa com a mortalidade para as três espécies nas duas gerações. O número de massas de ovos na F1 foi menor em S. frugiperda, não alterado para D. saccharalis e maior em H. zea.Palavras-chave: Helicoverpa zea, Spodoptera frugiperda, Diatraea saccharalis, vírus entomopatogênico.

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