The Co-occurrence Matrix and the Correlation Network of Phytophagous Insects Are Driven by Abiotic and Biotic Variables: the Case of Canola.

Co-occurrence a correlation profiles are driven by different factors (exogenous and endogenous) and drawing a profile of association between species based on co-occurrence, without assessing how these species vary in terms of ecological niche can lead to wrong conclusions. The objective was to determine the co-occurrence and correlation patterns of phytophagous insects in canola crop and to evaluate how these patterns varied according to the crop stage (phenology-biotic) and sowing times (agricultural practice-abiotic). We found that the patterns of co-occurrence and correlation between species were reflections of population variations due to the phenology and sowing times of canola.

Electrical signalling and plant response to herbivory: A short review.

For a long time, electrical signaling was neglected at the expense of signaling studies in plants being concentrated with chemical and hydraulic signals. Studies conducted in recent years have revealed that plants are capable of emitting, processing, and transmitting bioelectrical signals to regulate a wide variety of physiological functions. Many important biological and physiological phenomena are accompanied by these cellular electrical manifestations, which supports the hypothesis about the importance of bioelectricity as a fundamental 'model' for response the stresses environmental and for activities regeneration of these organisms.

Effects of co-occurrence and intra- and interspecific interactions between Drosophila suzukii and Zaprionus indianus.

In drosophilids, competition and coexistence can impact survivorship, growth, and reproductive output. Here, we evaluated direct competition between two co-occurring fruit flies, the spotted-wing drosophila Drosophila suzukii and the African fig fly Zaprionus indianus, comparing results from field collections with laboratory experiments. Field collections were conducted to evaluate co-occurrence between species.

Release strategies of Telenomus podisi for control of Euschistus heros: a computational modeling approach.

Background: The egg-parasitoid wasp Telenomus podisi has received attention as a biological-control agent for one of the most important soybean pests in Brazil, the stink bug Euschistus heros. As yet, no studies have conclusively established strategies for the release of T. podisi.

Refuge distributions and landscape connectivity affect host-parasitoid dynamics: Motivations for biological control in agroecosystems.

Species distributions are affected by landscape structure at different spatial scales. Here we study how the interplay between dispersal at different spatial scales and landscape connectivity and composition affect local species dynamics. Using a host-parasitoid model, we assessed host density and host occupancy on the landscape, under different parasitoid dispersal ranges and three local distributions of non-crop habitats, areas where hosts are unable to grow but parasitoids are provided with alternative hosts and food resources.

Oscillation, synchrony, and multi-factor patterns between cereal aphids and parasitoid populations in southern Brazil.

In different parts of the world, aphid populations and their natural enemies are influenced by landscapes and climate. In the Neotropical region, few long-term studies have been conducted, maintaining a gap for comprehension of the effect of meteorological variables on aphid population patterns and their parasitoids in field conditions. This study describes the general patterns of oscillation in cereal winged aphids and their parasitoids, selecting meteorological variables and evaluating their effects on these insects.

Ecological Modelling of Insect Movement in Cropping Systems.

The spatio-temporal dynamics of insect pests in agricultural landscapes involves the potential of species to move, invade, colonise, and establish in different areas. This study revised the dispersal of the important crop pests Diabrotica speciosa Germar and Spodoptera frugiperda (J.E.

Electrical signalling on Bt and non-Bt cotton plants under stress by Aphis gossypii.

Plants have developed various mechanisms to respond specifically to each biotrophic attack. It has been shown that the electrical signals emitted by plants are associated with herbivory stress responses and can lead to the activation of multiple defences. Bt cotton is a genetically modified pest-resistant plant that produces an insecticide from Bacillus thuringiensis (Bt) to control Lepidopteran species.

Shifts in Ecological Dominance between Two Lepidopteran Species in Refuge Areas of Bt Cotton.

Competition behavior involving agricultural pest species has long been viewed as a powerful selective force that drives ecological and phenotypic diversity. In this context, a Game Theory-based approach may be useful to describe the decision-making dilemma of a competitor with impacts to guarantee its superiority in terms of ecological dominance or sharing of the food resource with its competitor. In an attempt to elucidate the consequences of competitive dynamics for the ecological dominance of these species in refuge areas of Bt cotton, we conducted a study that was divided into two parts.

Imidacloprid-mediated stress on non-Bt and Bt cotton, aphid and ladybug interaction: Approaches based on insect behaviour, fluorescence, dark respiration and plant electrophysiology.

Plants and insects are parts of a complex system that involves interactions among many trophic levels, and it is important to understand the nature of such interactions. In the complex of interactions involving aphids and transgenic cotton expressing Bacillus thuringiensis, both the spraying of neonicotinoids and the occurrence of predatory coccinellids are common. However, there are gaps regarding the knowledge about possible impacts of neonicotinoids on physiological variables of the host plant and behavioural traits of the aphid (Aphis gossypii) and predator (Cycloneda sanguinea).

Modelling movement and stage-specific habitat preferences of a polyphagous insect pest.

Background: The feeding preferences of (Coleoptera: Chrysomelidae) cause a parent-offspring conflict, as providing the best host for the offspring development is detrimental to adult survival and fecundity. Understanding the implications of this conflict could help entomologists to implement pest-management programs. With this in mind, the foraging behaviour of was investigated using an individual-based model in two distinct scenarios.

Microclimatic Conditions for Dung Beetle (Coleoptera: Scarabaeidae) Occurrence: Land Use System as a Determining Factor.

Tropical forests account for 7% of the earth's surface harboring more than 50% of the biodiversity on Earth. Unfortunately, deforestation continues at high rates with negative consequences for biodiversity. With the decrease of natural habitats, biodiversity maintenance in areas degraded by human activity is a challenge.

The behavior of Aphis gossypii and Aphis craccivora (Hemiptera: Aphididae) and of their predator Cycloneda sanguinea (Coleoptera: Coccinellidae) in cotton-cowpea intercropping systems.

The intercropping is an important cultural practice commonly used in pest management. It is based on the principle that increased plant diversity in the agro-ecosystem can lead to reductions of pest populations in the crop. The current study aimed to assess the impact the colored fiber cotton-cowpea intercropped systems on Aphis gossypii and Aphis craccivora and on their predator Cycloneda sanguinea and the losses and the dispersion behavior of these aphids and their predator in these cropping systems.

Population dynamics of Aphis gossypii Glover and in sole and intercropping systems of cotton and cowpea.

Population dynamics of aphids have been studied in sole and intercropping systems. These studies have required the use of more precise analytical tools in order to better understand patterns in quantitative data. Mathematical models are among the most important tools to explain the dynamics of insect populations.

Larval Dispersal of Spodoptera frugiperda Strains on Bt Cotton: A Model for Understanding Resistance Evolution and Consequences for its Management.

High dispersal of Lepidoptera larvae between non-Bt and Bt cotton plants can favour the evolution of insect resistance; however, information on host acceptance of neonates in tropical transgenic crops is scarce. Therefore, the purposes of this study were as follows: (i) to investigate the feeding behaviour of susceptible and Cry1F-resistant strains of Spodoptera frugiperda (J.E.

Intraguild predation influences oviposition behavior of blow flies (Diptera: Calliphoridae).

The objective of the present study was to determine whether blow flies (Diptera: Calliphoridae) are able to identify larvae of an intraguild predator species in the substrate and avoid laying eggs there. Blow flies oviposited in traps with different treatments: substrate only and substrate with larvae of Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), or Chrysomya putoria (Wiedemann, 1830). Ch.

Better to Be in Bad Company than to Be Alone? Aedes Vectors Respond Differently to Breeding Site Quality in the Presence of Others.

This study focuses on two competing species, Aedes aegypti and Aedes albopictus (Diptera: Culicidae), both invasive mosquitoes of the New World. Context-specific competition between immature forms inside containers seems to be an important determinant of the coexistence or displacement of each species in different regions of the world. Here, competition experiments developed at low density (one, two or three larvae) and receiving four different resource food concentration, were designed to test whether Ae.

Interspecific Associations between Cycloneda sanguinea and Two Aphid Species (Aphis gossypii and Hyadaphis foeniculi) in Sole-Crop and Fennel-Cotton Intercropping Systems.

Aphids cause significant damage to crop plants. Studies regarding predator-prey relationships in fennel (Foeniculum vulgare Mill.) and cotton (Gossypium hirsutum L.

Temporal Overlap and Co-Occurrence in a Guild of Sub-Tropical Tephritid Fruit Flies.

Studies of community assembly have emphasized snapshot comparisons of spatially replicated samples from "natural" assemblages. Agro-ecosystems are characterized by relatively little habitat heterogeneity and no dispersal barriers for actively flying insects. Therefore, dynamic patterns of species segregation and aggregation are more likely to reflect the direct or indirect effects of species interactions.

The biology and thermal requirements of the fennel aphid Hyadaphis foeniculi (Passerini) (Hemiptera: Aphididae).

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 fennel (Foeniculum vulgare Miller (Apiales: Apiaceae)) crops would obviously benefit the effective application of control measures. This paper is a study of the biology and thermal requirements of H.

Estimating the development of the fennel aphid, Hyadaphis foeniculi (Passerini) (Hemiptera: Aphiididae), using non-linear models.

Background: Non-linear models making it possible to predict agricultural pest outbreaks and optimise control tactics are of primary importance for integrated pest management. The development period for immature stages of the fennel aphid Hyadaphis foeniculi (Passerini) (Hemiptera: Aphididae) at constant temperatures was modelled in order to determine mathematical functions for simulating the aphid's development. Non-linear models were used to describe the relationship between temperature and development rates of H.

Landscape diversity influences dispersal and establishment of pest with complex nutritional ecology.

We studied the effects of landscape structure on species with resource nutritional partition between the immature and adult stages by investigating how food quality and spatial structure of a landscape may affect the invasion and colonization of the insect pest, Diabrotica speciosa. To this end, we formulated two bidimensional stochastic cellular automata, one for the insect immature stage and the other for the adult stage. The automata are coupled by adult oviposition and emergence.

Spatio-temporal dynamics and preference for type of bait in necrophagous insects, particularly native and introduced blow flies (Diptera: Calliphoridae).

We carried out a year-long survey of insects, using carrion-baited traps in the municipality of Campinas and five surrounding municipalities with different urbanization profiles, in southeastern Brazil. We studied the spatio-temporal variability and preferences for type of bait of three blow fly species that are forensically important in Brazil: Chrysomya albiceps (Wiedemann), Chrysomya megacephala (F.), and Lucilia eximia (Wiedemann).

Bait and habitat preferences, and temporal variability of social wasps (Hymenoptera: Vespidae) attracted to vertebrate carrion.

In addition to feeding on carrion tissues and fluids, social wasps can also prey on immature and adult carrion flies, thereby reducing their populations and retarding the decomposition process of carcasses. In this study, we report on the occurrence and behavior of social wasps attracted to vertebrate carrion. The collections were made monthly from September 2006 to October 2007 in three environments (rural, urban, and forest) in six municipalities of southeast Brazil, using baited bottle traps.