Effect of the Insecticide Chlorpyrifos on Behavioral and Metabolic Aspects of the Spider Polybetes pythagoricus.

The toxicity of pesticides to organisms depends on the total amount of chemical exposure. Toxicity can be minimized if the organism recognizes the pesticide and alters its behavior. Furthermore, the physical barrier of cuticular hydrocarbons can prevent the entrance of the pesticide into the organism.

Embryonic and post-embryonic development of the spider Polybetes pythagoricus (Sparassidae): A biochemical point of view.

Analysis of energy expense during development has achieved special interest through time on account of the crucial role of the consumption of resources required for offspring survival. Spider eggs have a fixed composition as well as some initial energy that is supplied by mothers. These resources are necessary to support the metabolic expense not only through the embryonic period but also during the post-embryonic period, as well as for post emerging activities before spiderlings become self-sustaining.

Behavioral, Histological, and Physiological Evaluation of the Effect of Imidacloprid on the Spider Misumenops maculissparsus.

The aim of the present study was to evaluate the effects of the neonicotinoid insecticide imidacloprid (commercial formulation) on juveniles of the spider Misumenops maculissparsus (Keyserling, 1891). We first analyzed whether spiders recognized the presence of the insecticide on surfaces and in drinking water (in the form of droplets). Next, we investigated if the insecticide generated histologic, physiologic, and/or biochemical alterations.

Neighbour signals perceived by phytochrome B increase thermotolerance in Arabidopsis.

Due to the preeminence of reductionist approaches, understanding of plant responses to combined stresses is limited. We speculated that light-quality signals of neighbouring vegetation might increase susceptibility to heat shocks because shade reduces tissue temperature and hence the likeness of heat shocks. In contrast, plants of Arabidopsis thaliana grown under low-red/far-red ratios typical of shade were less damaged by heat stress than plants grown under simulated sunlight.

Biochemical and structural characterization of a novel arginine kinase from the spider .

Energy buffering systems are key for homeostasis during variations in energy supply. Spiders are the most important predators for insects and therefore key in terrestrial ecosystems. From biomedical interest, spiders are important for their venoms and as a source of potent allergens, such as arginine kinase (AK, EC 2.