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First record of larvae of Allograpta exotica Wiedemann (Diptera, Syrphidae) preying on Aphis gossypii Glover (Hemiptera, Aphididae) in watermelon in Brazil
Sturza, Vinícius Soares;Dorfey, Cecília;Poncio, S?nia;Dequech, S?nia Thereza Bastos;Bolzan, Anderson;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011005000015
Abstract: first record of larvae of allograpta exotica wiedemann (diptera, syrphidae) preying on aphis gossypii glover (hemiptera, aphididae) in watermelon in brazil. brazil is one of the largest world producers of watermelon (citrullus lanatus thumb. mansf.) and aphis gossypii glover, 1877 (hemiptera, aphididae) is among the most important pest on this crop. larvae of allograpta exotica wiedemann, 1830 (diptera, syrphidae) were found preying on a. gossypii in watermelon crop, in santa maria, rio grande do sul state, what represents the first report of this tritrophic association in brazil.
Effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with Aphis gossypii Glover (Hemiptera, Aphididae)
Alcantra, Eliana;Moraes, Jair Campos;Antonio, Alex;Alvarenga, Roberta;Fran?oso, Jonas;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011005000011
Abstract: effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with aphis gossypii glover (hemiptera, aphididae). the aphid aphis gossypii is an insect pest that causes damage mainly at the beginning of the cotton plant development. the effect of resistance inductors silicon and acibenzolar-s-methyl (asm) on the development of colored cotton plants were researched in the presence and absence of a. gossypii. three colored cotton cultivars were sown in pots and individually infested with 25 apterous aphids, 13 days after the application of the inductors. fifteen days after plant emergence, the silicon was applied at a dosage equivalent to 3 t/ha and acibenzolar-s-methyl in 0.2% solution of the product bion 500?. after 21 days of infestation the following parameters were evaluated: plant height, stem diameter, dry matter of aerial part and root, and total number of aphids replaced. it was verified that the plant height was reduced in the presence of aphids and all variables were negatively affected by the application of asm. however, silicon did not affect plant development.
Factors affecting colonization and abundance of Aphis gossypii glover (hemiptera: aphididae) on okra plantations
Leite, Germano Le?o Demolin;Pican?o, Marcelo;Zanuncio, José Cola;Gusm?o, Marcos Rafael;
Ciência e Agrotecnologia , 2007, DOI: 10.1590/S1413-70542007000200011
Abstract: the control of aphis gossypii glover (hemiptera: aphididae) on okra abelmoschus esculentus (l.) (malvaceae) consist primarily in the use of insecticides, due to the lack of information on other mortality factors. the objective of this study was to determine the effects of predators and parasitoids, height of canopy, plant age, leaf areas, organic compounds leaves, levels of leaf nitrogen and potassium, density of leaf trichomes, total rainfall and median temperature on attack intensity of a. gossypii on two successive a. esculentus var. santa cruz plantations. monthly number estimates of a. gossypii and natural enemies (visual inspection) occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant). plants senescence, leaf areas and natural enemies, mainly adialytus spp., spiders and coccinellidae, were some of the factors that most contributed to aphid reduction. a higher number of aphids was found on the bottom part than medium and apical parts of okra plants. total rainfall can reduce the aphid population. trichomes non-glandular or low density, organic compounds leaves and levels of n and k were not important for reducing aphid population.
Efeito da densidade de ninfas de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) no consumo alimentar e aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae)
Mendes, Simone M.;Bueno, Vanda H.P.;Carvalho, Lívia M.;Silveira, Luís Cláudio P.;
Revista Brasileira de Entomologia , 2003, DOI: 10.1590/S0085-56262003000100004
Abstract: effect of ninfal density of aphis gossypii glover, 1877 (hemiptera, aphididae) on feed consumption and biological aspects of orius insidiosus (say, 1832) (hemiptera, anthocoridae). the influence of different densities of a. gossypii (10, 20, 30, 40, 50, 60 nymphs/day) on consumption rate, development time, survival, and reproduction of orius insidiosus (say, 1832) was investigated. the trials were carried out in climatic chamber at 25 ± 1 °c, 70±10% rh, and photoperiod 12:12h (l:d). consumption rates of nymphs and adults increased under a linear form as the densities of aphids increased. development time was longest when reared in 10 nymphs density (15.4 days). nymphal survival was different under the densities of a. gossypii and no significant difference for the periods of preoviposition (4.8 days) and oviposition (8.9 days) were found. the oviposition increased with the prey densities (2.00, 11.33, 10.67, 21.30, 17.89 and 53.38 eggs), as well as the viability: 0.00, 52.49, 57.86, 58.14, 50.11 and 72.89%, respectively. nymphs of a. gossypii as prey were suitable for the complete development of o. insidiosus.
Efeito da densidade de ninfas de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) no consumo alimentar e aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae)
Mendes Simone M.,Bueno Vanda H.P.,Carvalho Lívia M.,Silveira Luís Cláudio P.
Revista Brasileira de Entomologia , 2003,
Abstract: Effect of ninfal density of Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) on feed consumption and biological aspects of Orius insidiosus (Say, 1832) (Hemiptera, Anthocoridae). The influence of different densities of A. gossypii (10, 20, 30, 40, 50, 60 nymphs/day) on consumption rate, development time, survival, and reproduction of Orius insidiosus (Say, 1832) was investigated. The trials were carried out in climatic chamber at 25 ± 1 °C, 70±10% RH, and photoperiod 12:12h (L:D). Consumption rates of nymphs and adults increased under a linear form as the densities of aphids increased. Development time was longest when reared in 10 nymphs density (15.4 days). Nymphal survival was different under the densities of A. gossypii and no significant difference for the periods of preoviposition (4.8 days) and oviposition (8.9 days) were found. The oviposition increased with the prey densities (2.00, 11.33, 10.67, 21.30, 17.89 and 53.38 eggs), as well as the viability: 0.00, 52.49, 57.86, 58.14, 50.11 and 72.89%, respectively. Nymphs of A. gossypii as prey were suitable for the complete development of O. insidiosus.
Desenvolvimento do Pulg?o Aphis gossypii Glover (Hemiptera: Aphididae) em Três Cultivares do Algod?o Herbáceo Gossypium hirsutum L. r. latifolium Hutch.
FERNANDES, ADRIANA M.V.;FARIAS, ?NGELA M.I.;SOARES, M?NICA M.M.;VASCONCELOS, SIM?O D.;
Neotropical Entomology , 2001, DOI: 10.1590/S1519-566X2001000300021
Abstract: we studied the development of aphis gossypii glover (hemiptera: aphididae) in three cultivars of the herbaceous cotton plant: cnpa precoce 1, cnpa precoce 2 and cnpa 7 h. cotton plants 20-cm high, maintained individually in caged pots, were infested with 20 adult aphids. we recorded the number of aphids in each plant of the three cultivars 15, 30 and 45 days after the infestation. significant differences were found in the mean number of aphid between the cultivar cnpa precoce 2 and the other cultivars. no significant difference was registered between the cultivars concerning to the vertical distribution of aphids on the plant, except at 45 days after infestation, when the cultivar cnpa precoce 2 presented higher density of aphids in the medium region in the comparison with the basal region.
The Population Abundance of Aphis gossypii Glover (Hemiptera: Aphididae) in Different Chilli (Capsicum annum) Planting Densities
H. T. Lee,A. B. Idris,M. N. Mohamad Roff
Journal of Biological Sciences , 2002,
Abstract: The population abundance of aphid, Aphis gossypii Glover in different chilli, Capsicum annuum, planting densities (plant spacing) was assessed. Results indicated that aphid population (alate and apterous) was significantly higher (P < 0.05) in the dense planting than in the sparse chilli planting density. The mean total number of aphids per plant was significantly higher (P<0.05) in the lower portion of plant canopy than in the middle and upper portion of plant canopies of the 40 x 40 cm2 plant spacing only. Plant spacing of 60 x 60cm2 seemed to be the optimum plant density that could reduce aphid population.
Custo adaptativo associado à resistência de Aphis gossypii Glover (Hemiptera: Aphididae) ao inseticida carbosulfam
Konno, Roberto H.;Omoto, Celso;
Neotropical Entomology , 2006, DOI: 10.1590/S1519-566X2006000200014
Abstract: in order to collect basic information for a resistance management program of aphis gossypii glover to carbosulfan, studies to evaluate fitness costs associated to this resistance were conducted under laboratory conditions. for this purpose, we studied the stability of carbosulfan resistance in a. gossypii populations with differing initial frequencies of resistance and compared life-history traits of carbosulfan-susceptible and resistant strains. the stability of resistance was followed in three populations with initial frequencies of 20, 50 and 80% of resistant individuals. the susceptibility to carbosulfan was monthly estimated by using the diagnostic concentration of 32 ppm. the biology of carbosulfan-susceptible and resistant strains was evaluated in cotton plants kept under controlled climatic conditions. the resistance to carbosulfan was unstable, that is, there was a significant increase in the susceptibility of different populations of a. gossypii to this insecticide in the absence of selection pressure. comparison of biological traits between carbosulfan-susceptible and resistant strains showed that there is a fitness cost associated with resistance. the resistant strain showed lower fecundity, shorter reproductive period and lower longevity than the susceptible strain. the net reproductive rate (ro) was 14.04 and 43.18 and the finite rate of increase (l) was 1.25 and 1.30 females/female/day for the resistant and susceptible strains respectively. therefore, the instability of carbosulfan resistance in a. gossypii can be exploited in resistance management programs.
Fecundidade e longevidade de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) em diferentes temperaturas e cultivares comerciais de crisantemo (Dendranthema grandiflora Tzvelev)
Soglia, Maria C. de M.;Bueno, Vanda H. Paes.;Rodrigues, Sandra M. M.;Sampaio, Marcus V.;
Revista Brasileira de Entomologia , 2003, DOI: 10.1590/S0085-56262003000100007
Abstract: fecundity and longevity of aphis gossypii glover, 1877 (hemiptera, aphididae) at different temperatures and commercial chrysanthemum cultivars (dendranthema grandiflora tzvelev). the aphid a. gossypii is one of the main pests in a number of crops both under field and protected conditions. the objective of the present study was to evaluate the fecundity and longevity of a. gossypii under different temperatures and commercial chrysanthemum cultivars (yellow snowdon, white reagan and dark splendid reagan) with different trichomes densities (11.3; 16.6 and 21.6 trichome/mm2 of the leaf, respectively) the trials were carried out in climatic chambers, at four temperatures (15, 20, 25 and 30 ±1 °c), 70 ± 10% rh and photophase 10h. the reproductive period significantly decreased with increase of temperature in the three cultivars. in yellow snowdon cultivar average duration of the reproductive period was 14.3 days at 25 °c. the maximum fecundity was obtained at the temperature of 25 oc with 3,1; 2,8 and 3,6 nymphs/female/day in the yellow snowdon, white reagan and dark s. reagan cultivars, respectively. the total fecundity was reduced by extreme temperatures (15 and 30 °c), and was obtained at 25 °c with 35,9 nymphs/female. females maintained in yellow snowdon cultivar significantly showed superiority (30,7 nymphs/female) in total fecundity in relation to white reagan (22,1 nymphs/female) and dark s. reagan (22,9 nymphs/female). the yellow snowdon cultivar (with a lower trichome density) had a significant influence in daily and total capacity of nymphs production, showing a higher fecundity of a. gossypii females. the aphid's longevity was affected by cultivars and temperature, and this longevity decreased whit increase of temperature. the results showed that there was an interaction between the temperature and host plant on reproductive parameters of a. gossypii.
Fecundidade e longevidade de Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) em diferentes temperaturas e cultivares comerciais de crisantemo (Dendranthema grandiflora Tzvelev)
Soglia Maria C. de M.,Bueno Vanda H. Paes.,Rodrigues Sandra M. M.,Sampaio Marcus V.
Revista Brasileira de Entomologia , 2003,
Abstract: Fecundity and longevity of Aphis gossypii Glover, 1877 (Hemiptera, Aphididae) at different temperatures and commercial chrysanthemum cultivars (Dendranthema grandiflora Tzvelev). The aphid A. gossypii is one of the main pests in a number of crops both under field and protected conditions. The objective of the present study was to evaluate the fecundity and longevity of A. gossypii under different temperatures and commercial chrysanthemum cultivars (Yellow Snowdon, White Reagan and Dark Splendid Reagan) with different trichomes densities (11.3; 16.6 and 21.6 trichome/mm2 of the leaf, respectively) The trials were carried out in climatic chambers, at four temperatures (15, 20, 25 and 30 ±1 °C), 70 ± 10% RH and photophase 10h. The reproductive period significantly decreased with increase of temperature in the three cultivars. In Yellow Snowdon cultivar average duration of the reproductive period was 14.3 days at 25 °C. The maximum fecundity was obtained at the temperature of 25 oC with 3,1; 2,8 and 3,6 nymphs/female/day in the Yellow Snowdon, White Reagan and Dark S. Reagan cultivars, respectively. The total fecundity was reduced by extreme temperatures (15 and 30 °C), and was obtained at 25 °C with 35,9 nymphs/female. Females maintained in Yellow Snowdon cultivar significantly showed superiority (30,7 nymphs/female) in total fecundity in relation to White Reagan (22,1 nymphs/female) and Dark S. Reagan (22,9 nymphs/female). The Yellow Snowdon cultivar (with a lower trichome density) had a significant influence in daily and total capacity of nymphs production, showing a higher fecundity of A. gossypii females. The aphid's longevity was affected by cultivars and temperature, and this longevity decreased whit increase of temperature. The results showed that there was an interaction between the temperature and host plant on reproductive parameters of A. gossypii.
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