Die Nanotechnologie umfasst die Synthese von im Nanobereich strukturierten Stoffen, das Verständnis und die Anwendung ihrer ungewöhnlichen physikochemischen und Schoemaker, Eur.

Fungi make piles of gold! A green‐chemistry route, based on the bioreduction of AuCl4− ions by the fungus Verticillium sp., for the formation of gold nanoparticles is demonstrated. The TEM micrograph shows a single Verticillium cell after reaction with gold ions and entrapment of gold nanoparticles on the cell wall and cytoplasmic membrane.

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Microbial interference plays an imperative role in plant development and response to various stresses. However, its involvement in mitigation of oxidative stress generated by plant parasitic nematode in plants remains elusive. In the present investigation, the efficacy of microbe's viz., Chitiniphilus sp. MTN22 and Streptomyces sp. MTN14 single and in combinations was examined to mitigate oxidative stress generated by M. incognita in medicinal plant, Bacopa monnieri. Microbial combination with and without pathogen also enhanced the growth parameters along with secondary metabolites (bacoside) of B. monnieri than the pathogen inoculated control. The study showed that initially the production of hydrogen peroxide (HO) was higher in dual microbes infected with pathogen which further declined over M. incognita inoculated control plants. Superoxide dismutase and free radical scavenging activity were also highest in the same treatment which was linearly related with least lipid peroxidation and root gall formation in B. monnieri under the biotic stress. Microscopic visualization of total reactive oxygen species (ROS), HO, superoxide radical and programmed cell death in host plant further extended our knowledge and corroborated well with the above findings. Furthermore, scanning electron microscopy confirmed good microbial colonization on the host root surface around nematode penetration sites in plants treated with dual microbes under pathogenic stress. The findings offer novel insight into the mechanism adopted by the synergistic microbial strains in mitigating oxidative stress and simultaneously stimulating bacoside production under pathogenic stress.

Mung bean is an important source of food for humans and animals in tropical and subtropical countries, and is also used for green manure. During spring 2008, mung bean plants in Faisalabad, Pakistan, showed severe symptoms of phyllody, virescence and a bushy appearance. Stem, leaf and stalk phloem sections from plants with and without symptoms were examined under a light microscope (CXRII, Labomed, CA, USA) using Dienes' stain. Regularly distributed dark blue areas were observed only in the phloem cells from plants with symptoms, and not in other plant tissues nor in the phloem of healthy plants, indicating the presence of a phytoplasma. Four week-old greenhouse-potted mung bean plants were grafted, and developed phyllody symptoms 25-30 days after grafting, similar to those observed in the field, whilst no symptoms developed in non-grafted control plants.To determine the 16Sr group of the phytoplasma associated with mung bean phyllody, total DNA was extracted from eight symptom-bearing plants, and amplified by nested PCR using universal 16S rDNA phytoplasma primers, P1 ⁄ P7 followed by R16F2n ⁄ R16R2. No symptomless plants were tested. All samples from plants with symptoms yielded a 1250bp PCR product, and identical RFLP profiles using the enzymes AluI and HpaII.