scholarly journals Biological parameters of three Trichogramma pretiosum strains (Riley, 1879) (Hymenoptera: Trichogrammatidae) on eggs Helicoverpa armigera (Hübner, 1805) (Lepidoptera: Noctuidae)

2017 ◽  
Vol 39 (3) ◽  
pp. 349 ◽  
Author(s):  
Gabriel dos Santos Carvalho ◽  
Luciana Barbosa Silva ◽  
Maisa Sousa Veras ◽  
Eliane Carneiro Bueno dos Santos ◽  
Mayra Layra dos Santos Almeida ◽  
...  
Keyword(s):  
Helicoverpa Armigera ◽  
Biological Parameters ◽  
Trichogramma Pretiosum ◽  
Helicoverpa Armígera ◽  
Lepidoptera Noctuidae

scholarly journals Performance of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) on eggs of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Valéria Lucas Laurentis ◽  
Dagmara Gomes Ramalho ◽  
Nathália Alves Santos ◽  
Vanessa Fabíola Pereira Carvalho ◽  
Alessandra Marieli Vacari ◽  
...  
Keyword(s):  
Helicoverpa Armigera ◽  
Trichogramma Pretiosum ◽  
Helicoverpa Armígera ◽  
Lepidoptera Noctuidae ◽  
Helicoverpa Armigera Hubner

scholarly journals Sublethal effects of different fungal isolates on Helicoverpa armigera (Lepidoptera: Noctuidae)

2020 ◽  
Vol 30 (1) ◽  
Author(s):  
Tamires Doroteo de Souza ◽  
Fabricio Oliveira Fernandes ◽  
Ariadne Costa Sanches ◽  
Ricardo Antônio Polanczyk
Keyword(s):  
Helicoverpa Armigera ◽  
Sublethal Effects ◽  
Mortality Rates ◽  
Probit Analysis ◽  
Control Measures ◽  
Pupal Weight ◽  
Main Body ◽  
Biological Parameters ◽  
Helicoverpa Armígera ◽  
Lepidoptera Noctuidae

Abstract Background Broad-spectrum pesticides and Bt crops have been used against the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), but their effect on the environment and the development of resistance are the main limitations for these control measures. The use of mycobiopesticides is an ecofriendly and efficient alternative. Fungicides have a wide distribution and a high genetic variability, which allows their screening for more virulent isolates. Therefore, the objective of this work was to evaluate the interactions of H. armigera larvae with Metarhizium anisopliae and Beauveria bassiana, on mortality, virulence, sublethal effects, and life table aspects. Main body The isolates that caused mortality rates of H. armigera above 80% were selected for further assays. Virulence was measured by LC50 estimates, using Probit analysis to sublethal effects, and the bootstrap procedure to estimate the biological parameters: time for development, fertility, longevity, pre-ovipositional period, egg viability, and sex ratio. The H. armigera mortality rates caused by B. bassiana and M. anisopliae ranged from 45 to 100% and from 40 to 90%, respectively. Longevity, fertility, and survival rates are affected in all treatments. The pupal weight of individuals treated with fungi was lower than in the control. Deformations were observed in H. armigera pupae developed from larvae treated with B. bassiana. Conclusion The use of sublethal concentrations of isolates of M. anisopliae and B. bassiana resulted in an adverse effect on the biological parameters of H. armigera.

scholarly journals Toxicity of Andira paniculata (Fabaceae) Extracts to Helicoverpa armigera (Lepidoptera: Noctuidae)

2018 ◽  
Vol 10 (6) ◽  
pp. 264
Author(s):  
Maurilio de Sousa Neto ◽  
Franciele Cristina da Silva ◽  
André Cirilo De Sousa Almeida ◽  
Antônio Carlos Severo Menezes ◽  
Márcio Da Silva Araujo ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Helicoverpa Armigera ◽  
Larval Stage ◽  
Dry Matter ◽  
Larval Period ◽  
Pupal Weight ◽  
Biological Parameters ◽  
Helicoverpa Armígera ◽  
Soybean Plants ◽  
Lepidoptera Noctuidae

Helicoverpa armigera is one of the most important pests of soybean crop in Brazil. The purpose of this work was to evaluate the effect of organic Andira paniculata extracts on its biology, feeding and the attractiveness of soybean plants to H. armigera. Hexane, dichloromethane, ethyl acetate and hydroalcoholic fractions at concentrations of 0.01, 0.1, 0.5 and 1% were evaluated. For the biological parameters the period and viability of larval stage, caterpillar weight at ten days, period, viability and pupal weight at 24 hours, total longevity, LC50 and deterrence were evaluated. The non-preference for feeding and attractiveness, the number of caterpillars and the dry matter consumed in each fraction of the extracts were evaluated. The extract of A. paniculata in hexane (0.01%) resulted up to 85% mortality of H. armigera. The A. paniculata extract did not affect the larval period, weight, pupal period and mortality or the consumption of H. armigera. The hydroalcoholic extracts obtained the better results for deterrence. The A. paniculata extract in dichloromethane fraction had the lowest LC50. The A. paniculata extracts in the hexane fractions (0.1%), ethyl acetate (0.01 and 0.5%) and hydroalcoholic (0.01 and 0.5%) were fagodeterrents for H. armigera. Thus, A. paniculata extract in hexane fraction is the most promising for use in the control of H. armigera in soybean.

scholarly journals Biological parameters and thermal requirements of Trichogramma pretiosum reared on Helicoverpa armigera eggs

2017 ◽  
Vol 52 (11) ◽  
pp. 961-968
Author(s):  
Gabriel dos Santos Carvalho ◽  
Luciana Barboza Silva ◽  
Soislan Sousa Reis ◽  
Maisa Sousa Veras ◽  
Eliane Carneiro ◽  
...  
Keyword(s):  
Helicoverpa Armigera ◽  
Life Stages ◽  
Biological Parameters ◽  
Trichogramma Pretiosum ◽  
Degree Days ◽  
Thermal Threshold ◽  
Thermal Requirements ◽  
Preimaginal Development ◽  
Helicoverpa Armígera ◽  
The Given

Abstract: The objective of this work was to determine the biological parameters and thermal requirements of Trichogramma pretiosum TM strain reared on Helicoverpa armigera eggs. A card containing 20 eggs of H. armigera was offered for each T. pretiosum female, at temperatures of 18, 20, 22, 25, 28, 30 and 32°C. All life stages of T. pretiosum were observed under the given temperature conditions. The optimum temperature for the parasitism of T. pretiosum was 25°C, and the highest longevity was found at the same temperature. The highest parasitoid emergence rates occurred at temperatures of 22, 25 and 28°C. The highest proportion of T. pretiosum individuals emerged per egg was observed at 18°C. Concerning the sex ratio, the highest proportion of females occurred at 28°C, and the highest percentage of parasitism viability was observed at this same temperature. The lowest thermal threshold for total preimaginal development and thermal requirements of T. pretiosum were 10.82°C and 134.55 degree-days, respectively. The estimated number of generations of T. pretiosum in the average temperatures of municipality of Bom Jesus, state of Piauí, Brazil is four per month.

Incidence of Helicoverpa armigera (Lepidoptera: Noctuidae) and its natural enemies on smallholder crops in Kenya

1993 ◽  
Vol 83 (3) ◽  
pp. 321-328 ◽  
Author(s):  
H. van den Berg ◽  
M. J. W. Cock ◽  
G. I. Oduor ◽  
E. K. Onsongo
Keyword(s):  
Helicoverpa Armigera ◽  
Heliothis Armigera ◽  
Population Densities ◽  
Parasitoid Species ◽  
Larval Parasitoid ◽  
Total Percentage ◽  
Four Seasons ◽  
Helicoverpa Armígera ◽  
Lepidoptera Noctuidae ◽  
Experimental Plots

AbstractSmallholder crops (sunflower, maize, sorghum and cotton) were grown in experimental plots at seven sites, representing different agricultural zones of Kenya, over four seasons. Helicoverpa armigera (Hübner) (formerly Heliothis armigera) only occasionally achieved population densities sufficient to cause obvious damage to the crops, and was virtually absent from the coastal sites. At the inland sites, infestation and mortality levels varied greatly. Information is presented on the incidence of H. armigera, and the identity, distribution and frequency of its common parasitoids and (potential) predators, sampled in the experimental plots. Trichogrammatoidea spp., egg parasitoids, and Linnaemya longirostris (Macquart), a tachinid late-larval parasitoid, were the most common parasitoid species, but total percentage parasitism was rather low. Of the large complex of predators, only anthocorids and ants (predominantly Pheidole spp., Myrmicaria spp. and Camponotus spp.) were sufficiently common and widespread to be of importance in suppressing H. armigera. The abundance of predators fluctuated widely between sites, but anthocorids were most abundant at the western sites.

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