The invasion of an established community by new species can trigger changes in community structure. Invasions often occur in phytophagous insect communities, the dynamics of which are driven by the structure of the host assemblage and the presence of competitors. In this study, we investigated how a community established through successive invasions changed over time, taking the last invasion a...

We studied the diversity of beetle families in watermelon fields palm grove Zaatote at Ouargla (34º 54′ N, 5º 20′ E). The sampling method used was Barber pots as they allowed largest number captures insects, regarding both individuals and species. Over three years study (2016, 2017 2018), we identified 787 from 12 taxonomic families. Throughout period, Coccinellidae family clearly dominant, wit...

Whether or not chemical changes in plants in response to pests (insects and pathogens) are general or specific remains unclear. Some evidence indicates that an induced response (IR) to arthropods via the octadecanoid pathway represents a distinct mechanism from the salicylic acid-based pathway of systemic acquired resistance (SAR) to pathogens. To further test this hypothesis, young cotton seed...

Many insects deposit marking pheromones following egg-laying that signal an occupied and thus sub-optimal resource. Herbivorous insects mark host fruit or other vegetative plant parts after depositing eggs, while insect parasitoids deposit such pheromones directly on the cuticle of a particular life stage of their prey. These oviposition marking pheromones (OMPs) are then recognized by conspeci...

Some specialist insects feed on plants rich in secondary compounds, which pose a major selective pressure on both the phytophagous and the gut microbiota. However, microbial communities of toxic plant feeders are still poorly characterized. Here, we show the bacterial communities of the gut of two specialized Lepidoptera, Hyles euphorbiae and Brithys crini, which exclusively feed on latex-rich ...

Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops...

While many insects cannot survive the formation of ice within their bodies, a few species can. On the evolutionary continuum from freeze-intolerant (i.e., freeze-avoidant) to freeze-tolerant insects, intermediates likely exist that can withstand some ice formation, but not enough to be considered fully freeze tolerant. Theory suggests that freeze tolerance should be favored over freeze avoidanc...

Experimental evidence is accumulating that endosymbionts of phytophagous insects may transmit horizontally via plants. Intracellular symbionts known for manipulating insect reproduction and altering fitness (Rickettsia, Cardinium, Wolbachia, and bacterial parasite of the leafhopper Euscelidius variegatus) have been found to travel from infected insects into plants. Other insects, either of the ...

1. The effect of the removal of Timarcha lugens (Chrysomelidae), one of the main herbivores of Hormathophylla spinosa (Cruciferae), on the abundance of co-occurring phytophagous insects, the abundance of non-phytophagous arthropods (detritivores, predators, and parasitoids), and the structure and diversity of the entire arthropod community, was studied for 3 years (1999–2001). 2. There was comp...

Interspecific interactions between insect herbivores can be either negative (competitive) or positive (facilitative) (Damman 1993, Denno et al. 1995). In the context of traditional community ecology, however, negative interactions have received the most attention (e.g., Lawton and Strong 1981, Schoener 1982, Strong et al. 1984, Denno et al. 1995) until quite recently (e.g., Lill and Marquis 200...