The use of mammals for studying microbial pathogens or for assessing the efficacy of a variety of pharmaceutical agents has contributed enormously to our knowledge of microbial virulence and in the development of novel therapeutic strategies. However, despite these advances, there is a recognition that the number of mammals used in such tests must be reduced to the minimum and that alternative,...

Phytophagous pentatomid insects can negatively impact agricultural productivity and the brown marmorated stink bug (Halyomorpha halys) is an emerging invasive pest responsible for damage to many fruit crops and ornamental plants in North America. Many phytophagous stink bugs, including H. halys, harbor gammaproteobacterial symbionts that likely contribute to host development, and characterizati...

Since 1996, the primary objective of the New Crop Pathology Program at the University of the Free State has been to conduct a systematic survey of diseases occurring in cactus-pear [Opuntia ficus-indica (L.) Miller] orchards throughout the country and to investigate possible relationships between disease-causing microorganisms and various insects, specifically Drosophila sp. Numerous fungal gen...

In the case of the pests inhabiting metal polluted or fields where the use of pesticides is common, a natural selection of resistant individuals can occur. This may pose serious problems for humans, agriculture, as well as the economies of many countries. In this study, the hypothesis that multigenerational (120 generations) exposure to cadmium of a beet armyworm population could be a selecting...

Behavior of extinct organisms can be inferred only indirectly, but occasionally rare fossils document particular behaviors directly. Brood care, a remarkable behavior promoting the survival of the next generation, has evolved independently numerous times among animals including insects. However, fossil evidence of such a complex behavior is exceptionally scarce. Here, we report an ensign scale ...

Plant-herbivore interactions provide well studied examples of coevolution, but little is known about how such interactions are influenced by the third trophic level. Here we show that larvae of the specialized lepidopteran herbivore Heliothis subflexa reduce their vulnerability to natural enemies through adaptation to a remarkable and previously unknown feature of their host plant, Physalis ang...

The occurrence of various catabolic pathways of glucose in plant materials has attracted considerable interest in recent years (1, 3, 6). In an earlier report (2), studies on the catabolism of glucose in fruit by a radiorespirometric method were described. The radiorespirometric method previously has been successfully applied to other intact biological systems such as microorganisms and insects...

Mycopathogens of economically important exotic invasive insects in forests of northeastern USA have been the subject of research at the Entomology Research Laboratory, University of Vermont, for the last 20 years. Elongate hemlock scale, European fruit lecanium, hemlock woolly adelgid and pear thrips were analyzed for the presence of mycopathogens, in order to consider the potential for managin...

The adaptive value of autumn colours is still a puzzle for evolutionary biology. It has been suggested that autumn colours are a warning signal to insects that use the trees as a host. I show that aphids (Dysaphis plantaginea) avoid apple trees (Malus pumila) with red leaves in autumn and that their fitness in spring is lower on these trees, which suggests that red leaves are an honest signal o...