Francisco de Souza Ramalho

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The high cost of insecticides, the emergence of insecticide resistance in populations of a number of insect species and other problems arising from their continuous use, such as biological imbalance, cotton fiber waste, and environmental pollution, have prompted the development of new technologies aiming the control of Anthonomus grandis Boheman in cotton(More)
The relationship between the insect development rate and temperature was established very early and represents an important ecological variable for modeling the population dynamics of insects. The accurate determination of thermal constant values and the lower and upper developmental thresholds of Hyadaphis foeniculi (Passerini) (Hemiptera: Aphididae) on(More)
Aphids cause significant damage to crop plants. Studies regarding predator-prey relationships in fennel (Foeniculum vulgare Mill.) and cotton (Gossypium hirsutum L.) crops are important for understanding essential ecological interactions in the context of intercropping and for establishing pest management programs for aphids. This study evaluated the(More)
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(More)
This study sought to provide relevant information for developing effective programs to manage Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) resistance to insecticides by quantifying and describing the interactions between cotton Bt and Podisus nigrispinus (Dallas) (Heteroptera; Pentatomidae) in the management of lambda-cyhalothrin resistance(More)
The relationship between pests and natural enemies using multivariate analysis on cotton in different spacing has not been documented yet. Using multivariate approaches is possible to optimize strategies to control Aphis gossypii at different crop spacings because the possibility of a better use of the aphid sampling strategies as well as the conservation(More)
The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry) can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus(More)
This research investigated the effects of neem oil on mortality, survival and malformations of the non-target stink bug predator, Podisus nigrispinus. Neurotoxic and growth inhibitor insecticides were used to compare the lethal and sublethal effects from neem oil on this predator. Six concentrations of neem oil were topically applied onto nymphs and adults(More)
The growth of the Brazilian forest sector with monocultures favors the adaptation of Arthropoda pests. The Lepidoptera order includes major pests of Eucalyptus spp. (Myrtaceae). The aim of this work is to study the population constancy, distribution, and frequency of Lepidoptera primary pests of Eucalyptus spp. Lepidoptera pests in Eucalyptus spp.(More)
Bracon vulgaris is a larval ectoparasitoid of the boll weevil, Anthonomus grandis, a key cotton pest We investigated the influence of parasitoid age, photoperiod and host availability on B. vulgaris parasitism. Five- and 10-day-old parasitoids were exposed to A. grandis densities of three, six, 12 and 24 larvae per female. Five-day-old females showed higher(More)