The Experts below are selected from a list of 22587 Experts worldwide ranked by ideXlab platform
Juan Ferre - One of the best experts on this subject based on the ideXlab platform.
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binding site alteration is responsible for field isolated resistance to bacillus thuringiensis cry2a insecticidal proteins in two Helicoverpa species
PLOS ONE, 2010Co-Authors: Silvia Caccia, Carmen Sara Hernandezrodriguez, R J Mahon, Sharon Downes, William James, Nadine Bautsoens, Jeroen Van Rie, Juan FerreAbstract:Background Evolution of resistance by target pests is the main threat to the long-term efficacy of crops expressing Bacillus thuringiensis (Bt) insecticidal proteins. Cry2 proteins play a pivotal role in current Bt spray formulations and transgenic crops and they complement Cry1A proteins because of their different mode of action. Their presence is critical in the control of those lepidopteran species, such as Helicoverpa spp., which are not highly susceptible to Cry1A proteins. In Australia, a transgenic variety of cotton expressing Cry1Ac and Cry2Ab (Bollgard II) comprises at least 80% of the total cotton area. Prior to the widespread adoption of Bollgard II, the frequency of alleles conferring resistance to Cry2Ab in field populations of Helicoverpa armigera and Helicoverpa punctigera was significantly higher than anticipated. Colonies established from survivors of F2 screens against Cry2Ab are highly resistant to this toxin, but susceptible to Cry1Ac.
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common receptor for bacillus thuringiensis toxins cry1ac cry1fa and cry1ja in Helicoverpa armigera Helicoverpa zea and spodoptera exigua
Applied and Environmental Microbiology, 2005Co-Authors: Carmen Sara Hernandez, Juan FerreAbstract:Binding studies using 125I-Cry1Ac and biotinylated Cry1Fa toxins indicate the occurrence of a common receptor for Cry1Ac, Cry1Fa, and Cry1Ja in Helicoverpa armigera, Helicoverpa zea, and Spodoptera exigua. Our results, along with previous binding data and the observed cases of cross-resistance, suggest that this pattern seems to be widespread among lepidopteran species.
Thomas E Hunt - One of the best experts on this subject based on the ideXlab platform.
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Intraguild interactions and behavior of Spodoptera frugiperda and Helicoverpa spp. on maize.
Pest Management Science, 2017Co-Authors: Jose P F Bentivenha, Thomas E Hunt, Edson Luiz Lopes Baldin, Débora G. Montezano, Julie A. Peterson, Vinicius S. Victor, Luiz Eduardo Da Rocha Pannuti, Ana María Vélez, Silvana Vieira De Paula-moraesAbstract:BACKGROUND Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hubner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. RESULTS In intraguild interactions, S. frugiperda had greater survival (55–100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. CONCLUSION Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry
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battle in the new world Helicoverpa armigera versus Helicoverpa zea lepidoptera noctuidae
PLOS ONE, 2016Co-Authors: Jose P F Bentivenha, Silvana Vieira De Paulamoraes, Ivana Fernandes Da Silva, Edson Luiz Lopes Baldin, Alexandre Specht, Thomas E HuntAbstract:The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape.
Jose P F Bentivenha - One of the best experts on this subject based on the ideXlab platform.
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Intraguild interactions and behavior of Spodoptera frugiperda and Helicoverpa spp. on maize.
Pest Management Science, 2017Co-Authors: Jose P F Bentivenha, Thomas E Hunt, Edson Luiz Lopes Baldin, Débora G. Montezano, Julie A. Peterson, Vinicius S. Victor, Luiz Eduardo Da Rocha Pannuti, Ana María Vélez, Silvana Vieira De Paula-moraesAbstract:BACKGROUND Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hubner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. RESULTS In intraguild interactions, S. frugiperda had greater survival (55–100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. CONCLUSION Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry
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battle in the new world Helicoverpa armigera versus Helicoverpa zea lepidoptera noctuidae
PLOS ONE, 2016Co-Authors: Jose P F Bentivenha, Silvana Vieira De Paulamoraes, Ivana Fernandes Da Silva, Edson Luiz Lopes Baldin, Alexandre Specht, Thomas E HuntAbstract:The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape.
Edson Luiz Lopes Baldin - One of the best experts on this subject based on the ideXlab platform.
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Intraguild interactions and behavior of Spodoptera frugiperda and Helicoverpa spp. on maize.
Pest Management Science, 2017Co-Authors: Jose P F Bentivenha, Thomas E Hunt, Edson Luiz Lopes Baldin, Débora G. Montezano, Julie A. Peterson, Vinicius S. Victor, Luiz Eduardo Da Rocha Pannuti, Ana María Vélez, Silvana Vieira De Paula-moraesAbstract:BACKGROUND Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is one of the major pests of maize and is in the same feeding guild as the noctuid pests Helicoverpa zea (Boddie) and Helicoverpa armigera (Hubner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interaction scenarios with non-Bt maize silks and ears. Moreover, a video tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food. RESULTS In intraguild interactions, S. frugiperda had greater survival (55–100%) when competing with Helicoverpa spp. in scenarios where larvae were the same instar or when they were larger (fourth versus second) than their competitor. Frequency and time in food of S. frugiperda larvae were negatively influenced by interactions. Larvae of S. frugiperda moved shorter distances (less than 183.03 cm) compared with H. zea. CONCLUSION Overall, S. frugiperda had a competitive advantage over Helicoverpa spp. This study provides significant information regarding noctuid behavior and larval survival during intraguild interactions, which may impact pest prevalence and population dynamics, thereby affecting integrated pest management and insect resistance management of these species in maize. © 2017 Society of Chemical Industry
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battle in the new world Helicoverpa armigera versus Helicoverpa zea lepidoptera noctuidae
PLOS ONE, 2016Co-Authors: Jose P F Bentivenha, Silvana Vieira De Paulamoraes, Ivana Fernandes Da Silva, Edson Luiz Lopes Baldin, Alexandre Specht, Thomas E HuntAbstract:The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape.
Silvana Vieira De Paulamoraes - One of the best experts on this subject based on the ideXlab platform.
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battle in the new world Helicoverpa armigera versus Helicoverpa zea lepidoptera noctuidae
PLOS ONE, 2016Co-Authors: Jose P F Bentivenha, Silvana Vieira De Paulamoraes, Ivana Fernandes Da Silva, Edson Luiz Lopes Baldin, Alexandre Specht, Thomas E HuntAbstract:The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape.