22 research outputs found
Does co-inoculation of Lactuca serriola with endophytic and arbuscular mycorrhizal fungi improve plant growth in a polluted environment?
Metal uptake by xerothermic plants introduced into Zn-Pb industrial wastes
The dusty surfaces of post-flotation wastes
contain high concentrations of toxic compounds and
spread widely if appropriate vegetation is not
introduced. It has been previously established that
effective restoration of such waste areas are best met
by xerothermic, mycorrhiza-assisted plants (Turnau
et al. Plant and Soil 305:267-280, 2008). The aim of
the current study was to improve phytostabilisation
practices by gaining insight into the elements uptake
in plants after their change of habitat. Total Reflection X-ray Fluorescence (TXRF) was employed to
evaluate element concentration in the leaves of 23
plant species growing in the wild and on Zn-Pb
waste. Higher levels of heavy metals (Zn, Y, As, Pb,
Cu) in plants from tailings were usually accompanied by increased Ca concentration, suggesting a
possible role of this element in detoxification
mechanisms. Also, when compared to grassland
specimens, plants from the tailings, exhibited
potassium-deficiency. Thus, K-supplementation of
the waste substrata should be considered to improve
plant growth. Among all the introduced plants, three
grass species (Melica transsilvanica, Bromus inermis, Elymus hispidus) and one legume (Anthylis
vulneraria) were the most suitable for phytostabilisation. Heavy metal-accumulating properties of
Verbascum thapsus need further investigation
Effects of genetic modifications to flax (Linum usitatissimum) on arbuscular mycorrhiza and plant performance
Although arbuscular mycorrhizal fungi (AMF) are known for their positive effect on flax growth, the impact of genetic manipulation in this crop on arbuscular mycorrhiza and plant performance was assessed for the first time. Five types of transgenic flax that were generated to improve fiber quality and resistance to pathogens, through increased levels of either phenylpropanoids (W92.40), glycosyltransferase (GT4, GT5), or PR2 beta-1,3-glucanase (B14) or produce polyhydroxybutyrate (M50), were used. Introduced genetic modifications did not change the degree of mycorrhizal colonization as compared to parent cultivars Linola and Nike. Arbuscules were well developed in each tested transgenic type (except M50). In two lines (W92.40 and B14), a higher abundance of arbuscules was observed when compared to control, untransformed flax plants. However, in some cases (W92.40, GT4, GT5, and B14 Md), the mycorrhizal dependency for biomass production of transgenic plants was slightly lower when compared to the original cultivars. No significant influence of mycorrhiza on the photosynthetic activity of transformed lines was found, but in most cases P concentration in mycorrhizal plants remained higher than in nonmycorrhizal ones. The transformed flax lines meet the demands for better quality of fiber and higher resistance to pathogens, without significantly influencing the interaction with AMF
Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats
Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research