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Campina Grande, Brazil

Plata-Rueda A.,Federal University of Vicosa | Martinez L.C.,Federal University of Vicosa | Fernandes F.L.,Federal University of Vicosa | De Sousa Ramalho F.,Unidade de Controle Biologico | And 2 more authors.
Journal of Economic Entomology | Year: 2016

Rhynchophorus palmarum (L.) causes great losses to the oil palm plantations, and therefore, the spatial and temporal distribution of this insect should be studied, to manage its populations. Insect sampling was done for 2 yr in an oil palm plantation from Colombia. In total, 60 pheromone traps were used in healthy palm trees and infected ones with the Bud Rot disease. On the other hand, developmental stages of this insect were quantified on healthy and diseased palms for two consecutive years. Number of adult R. palmarum per sampling was higher in the plantation with diseased palm trees, 3.85 and 74.7 insects per trap, than in those with healthy ones, 1.91 and 9.48 insects per trap, in the first and second years, respectively. After the integration of pheromone traps, there was a significant increase in the infestation level at all stages of development of the insect. For the first time, the presence of R. palmarum attracted to diseased palms is reported. The association between R. palmarum and the Bud Rot disease is a cause of death and great loss to the oil palm plantations. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.

Ribeiro R.C.,Federal University of Vicosa | Zanuncio T.V.,Federal University of Vicosa | Ramalho F.D.S.,Unidade de Controle Biologico | da Silva C.A.D.,Unidade de Controle Biologico | And 2 more authors.
Industrial Crops and Products | Year: 2015

The resistance, negative impacts on non-target organisms, and residues in food of synthetic pesticides necessitates the development of environmentally safe products for use in pest control. The objective of this research was to evaluate feeding and oviposition of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae) with sublethal concentrations of essential oils of condiments from ten plants, neem oil emulsion (Azamax®), and pyrethroid (Keshet® 25 EC). Bioassays were conducted in the laboratory and in a greenhouse setting using leaf disks (10.25cm2 diameter) and soybean plants in the vegetative stage V3 with and without choice. The rate of feeding deterrence (IDF) and oviposition (IDO) of A. gemmatalis were calculated after 24 and 48h of exposure to treatments, respectively. The cinnamon essential oils showed moderate antifeeding effect with IDF >50% of cinnamon mint thyme and garlic essential oils and high repellence of oviposition activity with IDO >80%. The velvetbean moth were attracted to synthetic mustard oil. The essential oils of garlic were most effective in reducing the feeding of velvetbean moth and oviposition of A. gemmatalis females and are therefore of interest in integrated pest management. © 2015.

Ramalho F.S.,Unidade de Controle Biologico | Malaquias J.B.,Unidade de Controle Biologico | Lira A.C.S.,Unidade de Controle Biologico | Oliveira F.Q.,Sao Paulo State University | And 2 more authors.
PLoS ONE | Year: 2015

Hyadaphis foeniculi (Passerini) (Hemiptera: Aphididae) is a cosmopolitan species and the main pest of fennel in northeastern Brazil. Understanding the relationship between temperature variations and the population growth rates of H. foeniculi is essential to predict the population dynamics of this aphid in the fennel crop. The aim of this study was to measure the effect of constant temperature on the adult prereproductive period and the life table fertility parameters (infinitesimal increase ratio (rm), gross reproduction rate (GRR), net reproduction rate (R0), finite increase ratio (λ), generation time (GT), the time required for the population to double in the number of individuals (DT), and the reproduction value (RVx)) of the fennel pest H. foeniculi. The values of lx (survival of nymphs at age x) increased as the temperature rose from 15 to 28°C and fell at 30°C, whereas mx (number of nymphs produced by each nymph of age x) increased from 15 to 25°C and fell at 28 and 30°C. The net reproduction rates (R0) of populations of H. foeniculi increased with temperature and ranged from 1.9 at 15°C to 12.23 at 28°C for each generation. The highest population increase occurred with the apterous aphids at 28°C. The rate of population increase per unit time (rm) (day) ranged from 0.0033 (15°C) to 0.1995 (28°C). The highest values of rm were recorded at temperatures of 28°C and 30°C. The rm values were a good fit to the models tested, with R2>0.91 and R2adj> 0.88. The models tested (Davidson, Sharpe and DeMichele modified by Schoolfield et al., Logan et al., Lamb, and Briere et al.) were very good fits for the rm values observed, with R2 > 0.91 and R2adj > 0.88. The only exception was the Davidson model. Of the parameters studied, the reproductive capacity was higher in the apterous aphids, with the unique exception of daily fecundity at 28°C, which was higher in the alate aphids of H. foeniculi. Parameters relating to the age-specific fertility table for H. foeniculi were heavily influenced by temperature, with the highest biotic potential and population growth capacity found at 34°C. Therefore, the results obtained in this study could be of practical significance for predicting outbreaks of fennel aphids and improving the management of this aphid in fennel crops. © 2015 Ramalho et al.

Fernandes F.S.,Unidade de Controle Biologico | Ramalho F.S.,Unidade de Controle Biologico | Malaquias J.B.,Unidade de Controle Biologico | Nascimento Jr. J.L.,Unidade de Controle Biologico | And 2 more authors.
Anais da Academia Brasileira de Ciencias | Year: 2012

We describe the vertical and horizontal distribution of the cotton aphid Aphis gossypii Glover within a cotton plant in two cotton (Gossypium hirsutum Linnaeus) cultivars (BRS Safira and BRS Rubí) with colored fiber over the time. Measurements of aphid population dynamics and distribution in the cotton plants were recorded in intervals of seven days. The number of apterous or alate aphids and their specific locations were recorded, using as a reference point the location of nodes on the mainstem of the plant and also those on the leaves present on branches and fruit structures. The number of apterous aphids found on the cultivar BRS Safira (56,515 aphids) was greater than that found on BRS Rubí (50,537 aphids). There was no significant difference between the number of alate aphids found on the cultivars BRS Safira (365 aphids/plant) and BRS Rubí (477 aphids/ plant). There were interactions between cotton cultivar and plant age, between plant region and plant age, and between cultivar and plant region for apterous aphids. The results of this study are of great importance in improving control strategies for A. gossypii in the naturally-colored cotton cultivars BRS Safira and BRS Rubí.

dos Santos B.D.B.,Unidade de Controle Biologico | Ramalho F.S.,Unidade de Controle Biologico | Malaquias J.B.,Unidade de Controle Biologico | Lira A.C.S.,Unidade de Controle Biologico | And 3 more authors.
Entomologia Experimentalis et Applicata | Year: 2016

The functional response of a predator to the density of its prey is affected by several factors, including the prey's developmental stage. This study evaluated the functional response of Podisus nigrispinus (Dallas) (Hemiptera: Heteroptera: Pentatomidae) females to fourth instars and pupae of Alabama argillacea (Hübner) (Lepidoptera: Noctuidae), an important pest of cotton (Gossypium hirsutum L., Malvaceae) in Brazil. The prey were exposed to the predator for 12 and 24 h, and in densities of 1, 6, 12, 18, 24, and 30 items per predator female. The predation data were subjected to polynomial regression logistic analysis to determine the type of functional response. Holling and Rogers' equations were used to estimate parameters such as attack rate and handling time. Podisus nigrispinus females showed functional response types II and III by preying on larvae and pupae, respectively. The attack rate and handling time did not differ between the 12 and 24 h exposure times. Predation rate was higher at higher larval and pupal densities; predation was highest at a density of 30 prey items per female, and it was similar at 18 and 24 prey per predator. Understanding the interaction of predators and their food resources helps to optimize biological control strategies. It also helps the decision-making and the improvement of release techniques of P. nigrispinus in the field. © 2016 The Netherlands Entomological Society.

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