5,378 research outputs found
Efeito da emissão de CO2 em ovos de Spodoptera frugiperda (J. E. Smith) parasitados por Telenomus remus Nixon.
Efeito do aumento da temperatura noturna na eficiência de Telenomus remus Nixon em ovos de Spodoptera frugiperda (J.E. Smith).
Preferência de Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) por lagartas de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) de diferentes idades.
Impacto de inseticidas sobre ovos de Spodoptera frugiperda, parasitados ou não por Telenomums sp.
Effect of Telenomus remus Nixon (Hymenoptera: scelionidae) density on control of Spodoptera frugiperda (Smith) (Lepidoptera: noctuidae) egg masses upon release in a maize field.
The impact of releasing different densities (0, 6, 9 and 12 adult females m-2) of the egg parasitoid Telenomus remus Nixon on maize plants artificially infested with Spodoptera frugiperda (Smith) egg masses (one m-2) was evaluated. Egg masses were pinned in the mid-rib of the plant 36 days after planting. One egg mass contained approximately 65 eggs. The experimental design was in a randomized complete block design with five replications (16 m2 plots). There was a significant effect on percentage of parasitism egg masses. The highest parasitism values were verified in plots where 9 or 12 females of T. remus m-2 were released, respectively, 74 and 88.3 %. The relationship between percentage of parasitized egg masses and parasitoid densities was quadratic (Y = 16.8 + 9.98 X - 0.35 X2, r2 = 0.99). The natural occurrence of Trichogramma spp. was relatively constant over the egg masses fixed on maize plants (52.5%). However, the average T. remus parasitism on the eggs of a mass was much higher, representing 80.4% while the parasitism was only 21.3% in the case of Trichogramma. The presence of both parasitoids was responsible for up to 97.5% of parasitism, obtained from plots with a released density of 12 T. remus female m-2
Effect of a nuclear polyhedrosis virus on Spodoptera frugiperda (Smith) (Lepidoptera:noctuidae) larvae, its damage and yield of maize crop.
The efficiency of Baculovirus in a wettable powder formulation to control the fall armyworm Spodoptera frugiperda (Smith) was evaluated using variations of the recommended dose of 50 grams per hectare (2.5 x 1011 polyhedron inclusion bodies - PIB ha-1): 50 or 100 g ha-1 applied once, and variations of two applications at seven-day intervals, of 25+25, 25 + 50, 50+25 and 50+50 g ha-1, compared to untreated plots. The treatments were arranged in a randomized complete block design with six replications. Each plant at 6-8 or 8-10-leaf growth stages, was artificially infested with 10 newly hatched larvae. The virus suspension (300 L ha-1) was applied 24 hours after larvae infestation using a back-pack-manual sprayer at 40 PSI (2.8 kg cm-2) and a regular flat fan nozzle. Larval mortality rate obtained from plots with the application of 50 g of Baculovirus wettable formulation ha-1, at once (96.2%), was significantly higher than that obtained with the application of 25+25 g ha-1 (85.3%) or 25 + 50 g ha-1 (87.8%). However, it was lower than that obtained from the other virus treatments, which had no significant difference among them (mean of 99.2%). The damage caused by S. frugiperda on the leaves of plants of untreated plots (average of 4.5 in an visual scale from 1 to 5) was significantly different from that observed in plots sprayed with virus (1.75 to 2.33). Plants protected with the virus produced significantly higher yield (mean of 7,577 kg ha-1) than plants unprotected (6,140 kg ha-1), that is, 23.4% higher
Levantamento de inimigos naturais de Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Pyralidae) em colmos de milho (Zea mays L.) cultivados em dois sistemas de produção.
Efeito do inseticida Fury e sua interação com os inimigos naturais no controle de Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) na cultura do milho.
Efeito do inseticida Lorsban na supressão de Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) na cultura do milho.
Efeito do inseticida Fury no controle de Spodoptera frugiperda (Smith, 1797) (Lepidoptera: noctuidae) na cultura do milho.
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