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Saxifraga stellaris var. alpigena grows as one of the very few higher plants in the copper rich area of the "blue creek" in Austria. Two endophytes were isolated from it: Mortierella sp. (fungus), and Stenotrophomonas maltophilia (bacterium). Both microbes were practically inseparable due to resistance of the bacteria to the antibiotics tested. On PDA media, the fungus showed higher tolerance to copper than the bacterium, which disappeared from both the media and the surface of the fungus in the presence of 150 μM of Cu. However, at this Cu concentration, the bacteria were still detectable inside the mycelium and reappeared on the outside when transferred to media of lower Cu concentration. Microscopic studies of in vitro cultivated plants showed that the fungus was present in both, the roots and shoots of the plant. The effects of endophytes on plant performance were assessed in rhizoboxes filled with Cu-rich substratum; plants inoculated with both microbes showed better growth, survival and photosynthesis performance than the non-inoculated controls. The results of this study prove the beneficial influence of the isolated endophytes on the Cu tolerance of S. stellaris, and indicate the ecological potential of applying microbial consortia to plants under extreme environmental conditions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The influence of acrylamide, a potentially toxic substance present in some types of food, on survival, postembryonic development and haemocytes, insect's blood cells, of the housefly was examined. Larvae were reared on media contaminated with acrylamide at concentrations of 82 microg/g, 164 microg/g or 246 microg/g. The length of larval and pupal stages as well as the survival of larvae and pupae was examined. To study the effects of acrylamide on haemocytes, the analysis of their index and morphology was performed in the third instar larva. The obtained data showed that the survival of larvae exposed to 82 microg/g and 164 microg/g concentrations of acrylamide decreased by 50% and 85%, respectively, whereas 246 microg/g concentration was lethal. In both groups of flies, larval and pupal stages were significantly lengthened by about 1.5 day in comparison with control. Moreover, acrylamide increased the number of prohaemocytes and intermediate cells while the number of plasmatocytes and granulocytes decreased. The size of plasmatocytes decreased in acrylamide-treated larvae when compared with these cells of control flies. The reduced survival of animals is probably due to affecting haemocytes involved in immune responses in insects. Moreover, the housefly's blood cells showed to be sensitive to toxin, which suggests their usefulness to test toxicity of substances present in food products.