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The main objective of this study was to investigate Artemisia annua plant property variations in terms of plant biomass, glandular trichome numbers, artemisinin production and Guaiacol peroxidase (GPOX) activity when plants are in mutualism with AMF. According to the results, A. annua mutualism with AMF significantly increased the most important and pharmaceutically relevant factors of fresh and dry plant biomass. This increase, especially in the biomass of plant herba (leaves), was 30% higher during the vegetation period and remained high (29% higher than for control) when plants were harvested at the end of the vegetation period. Similar differences in dry biomass were also detected. Glandular trichomas numbers increased by 40%, and the artemisinin content by 17% under AMF colonization. No effects due to AMF on chlorophyll variations were detected, while GPOX enzyme concentrations increased significantly under AMF colonization. Altogether the Artemisia plant properties with high pharmaceutically importance (fresh and dry biomass of leaves and artemisinin, number of trichomes and the artemisinin content) were significantly improved by AMF, the application in Artemisia cultivation can be an effective and cheap method. The high GPOX activity under AMF colonization indicate an enhanced oxidative stress alleviation, therefore a higher resistance to water deficiency, mechanisms important under climate conditions with low water supply where Artemisia is usually cultivated.

Abstract. We analysed the spatial and temporal variation of breeding habitat availability and use by a yellow-bellied toad population in a mixed deciduous forest between 20032005. During this period, the number of temporary ponds was highly variable. Toads tended to exploit newly created breeding habitats or those of which hydroperiod increased due to precipitation. Ponds with intermediate and long duration were preferred for reproduction. We found no evidence of predator avoidance behaviour (aquatic invertebrates and newts) or reproductive failure in ponds containing aquatic predators. Ponds located in sunny patches of the forest were preferred for reproduction. We suggest that ponds that act as sinks in years with low precipitation could contribute to the demography of toad populations in rainy years, when their hydroperiod increases.

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Aims We tested whether chemical content of individual Tansy plants influences aboveground arthropod and belowground soil microbial community composition. Methods We use Tansy chemical defence composition as focus for our analysis, given that changes in chemical defence are a dominant mechanism expected to modify aboveground and belowground community composition and nutrient cycling. Detailed assessment of arthropod food webs were made on tansy chemotypes. Next generation soil DNA analyses were used to assess soil bacterial community. Results Tansy plants defended by Camphor and Borneol had higher total soil bacterial diversity than control plants (soils under non-Tansy plants) and Tansy chemotypes containing high concentrations of Thujon. Furthermore, the frequency of bacterial genera with a significant role in litter mineralization processes decreased with time in soil associated with Camphor and Borneol chemotypes, indicative of complete microbial decomposition and mineralization of plant material. No such changes occurred in soils associated with Thujon chemotypes. Thujon plants had fewer aphids, ladybirds, spiders, and Orius sp. than other chemotypes. Conclusions Our experiments revealed that Thujon chemotypes had different associated aboveground arthropod and belowground soil microbial communities than Camphor or Borneol chemotypes. The common qualitative response between aboveground and belowground communities to Tansy plant defense is consistent with our hypothesis and extensive literature on plant defense and aboveground and belowground feedbacks.