No abstract

The ecology of Tribolium castaneum (Herbst) outside of grain storage facilities is poorly known. However, high densities of T. castaneum adults are known to infest stored cotton seeds (Gossypium hirsutum (L.

Tribolium castaneum, also known as the rust-red flour beetle, infests and consumes a variety of bulk stored food products and is a major pest of bulk stored grains globally.However, T. castaneum adults have been shown to infest stored cotton seeds heavily in Queensland, Australia, despite the absence of stored grain products nearby. Previous studies suggest that the beetles are attracted to the fungal colonies growing on the fibre that remains on the delinted seeds, but their relationship with these fungi has not been clarified. Moreover, little is known about the interactions of T. castaneum with particular species of fungi. That is, the associations between particular micro-fungi and T. castaneum may well be important factors in determining crucial aspects of the ecology of T. castaneum, both within and outside of stored grain systems. Further impetus for this study comes from the lack of clarity about the origins of T. castaneum before the advent of bulk stored grains, as their diet may have included particular fungal species (at least according to some authors).To investigate the associations between T. castaneum and micro-fungal species I conducted a number of laboratory and field experiments. These experiments included the identification of the fungal species I isolated from stored cotton seeds and wheat collected in South East Queensland. The feeding preferences of the adult beetles were determined using no-choice feeding tests for each of the fungal species. Further, the developmental success of the larvae was quantified on cotton seeds infested by one each of the fungal species identified. Gut analyses of T. castaneum adults, exposed to no-choice feeding tests, showed that the beetles will feed on all 14 fungal species when exposed to cotton seeds that had been inoculated with each of the fungal species, over 14 days. The developmental success of the larvae varied depending on the fungal species, with most fungal species supporting only low levels of successful developmental to adulthood (<30% relative to the standard culture diet of wheat flour and yeast). Volatile toxicity tests also revealed that neither adult or larval mortality was significantly affected by the presence of the identified fungal isolates. These results indicate that T. castaneum will feed on a variety of fungal species but that none of the tested fungal species on its own provides a good diet for T. castaneum. 3 Choice tests were conducted under laboratory conditions in a y-tube olfactometer and in wind tunnel assays to determine if any of the identified fungal species were attractive and/or repellent to the adult beetles. The olfactometer experiments revealed that the insects are attracted to the volatiles associated with Aspergillus tamarii and that they are repelled by those of Asp. ochraceus, Epicoccum nigrum and Penicillium citrinum. The wind tunnel assays returned significantly different results with the insects being repelled by Asp. tubingensis, and with no fungi attracting the beetles. Additional tests were also used to d...

The UK's -and the world's -'green industrial revolution' is intrinsically tied to the artisanal and small-scale mining (ASM) of cobalt in the Democratic Republic of Congo (DRC). This largely informal sector produces approximately 12-21% of the world's cobalt each year -a vital component in the manufacture of electric vehicle batteries powering the global transition to a low carbon economy and employing as many as 200,000 cobalt miners in DRC as well as supporting hundreds of thousands more people in related livelihood activities. Yet many artisanal cobalt miners suffer dangerous working conditions, human rights abuses, and include children.