Research onOrobanche crenata management in sicily from the 19 th to the early 20 th century

In order to offer hints for new research, the agronomic techniques used to manageOrobanche crenata in Sicily in the late 19 ^th and early 20 ^th Century are examined; the publications in which they were originally described can be obtained only with difficulty. Hand pulling, resistant cultivars and late sowing are the techniques used nowadays. Screening for resistance to broomrape of the traditional cultivars of broad bean, and for the influence of sowing density on broomrape infestations, is still to be done.     

A combined analysis based on microbial communities and volatile organic compounds as a tool to study soil quality in an urban environment

<正>Dear Editor,Soil quality is defined as“the capacity of a soil to function,within ecosystem and land use boundaries,to sustain productivity,maintain environmental quality,and promote plant and animal health”(Doran and Parkin 1994).In this context,soil functionality is fundamental to the biosphere and is highly dependent on the associated microbiota.Soil microorganisms are relevant for terrestrial ecosystem functioning,and understanding the functional changes of the biological community i...     

The influence of phosphate fertilizers on Cd solubility in soil

We investigated the influence of monoammonium phosphate (MAP) and diammonium phosphate (DAP) on the adsorption process of Cd by two typic soils. The phosphate induced variations in the pH values of soil-Cd suspensions, drastically influenced the solubility of the heavy metal in the two soils. MAP decreased the amount adsorbed while DAP increased the quantity fixed by the soil. The effect was particularly remarkable in the soil with low content of organic matter (Lamporecchio soil) where the addition of DAP caused the precipitation of the heavy metal. In the organic soil (Orentano soil) the effect of phosphate was less evident because of the high buffering capacity of this soil, rich in colloidal fractions.     

Phytoremediation of a multi contaminated soil: mercury and arsenic phytoextraction assisted by mobilizing agent and plant growth promoting bacteria

Purpose

The possibility of using chemical and microbial additives to enhance the phytoextraction of mercury (Hg) and arsenic (As) from a multi-contaminated soil could be very effective, leading to a significant saving in terms of time and costs of the reclamation. The aim of this study was to evaluate the efficacy of the addition of (i) thiosulfate and (ii) metal-tolerant bacteria isolated from the polluted soil having plant growth promotion (PGP) potential to perform As and Hg phytoextraction by Brassica juncea and Lupinus albus.

Materials and methods

A collection of 13 bacterial isolates able to tolerate As and Hg was obtained from the contaminated soil, identified by partial 16S rRNA gene sequencing and tested in vitro for PGP activities. The most promising strains were further tested in vivo for the evaluation of plant growth ability and rhizocompetence on model plants. Pot experiments were conducted in microcosms, with polluted soil vegetated with B. juncea and L. albus. Ammonium thiosulfate and potassium dihydrogen phosphate were used as mobilizing agents, together with a bacterial consortium composed by the most promising PGP isolates.

Results and discussion

Thirteen indigenous metal-tolerant bacterial strains were isolated, and their in vitro characterization highlighted their great potential in assisting the phytoremediation process; most of them tolerated both trace elements and showed, at the same time, multiple PGP traits. The results were confirmed in vivo on model plants and lead to the selection of the most promising PGP strains to be applied in microcosm-scale phytoextraction experiments. Thiosulfate addition significantly increased the mobilization of both elements, promoting bioavailability and phytoextraction. When a selected bacterial consortium was supplemented in addition to thiosulfate, the efficacy of the phytoaccumulation was increased up to 85 % for As and up to 45 % for Hg.

Conclusions

The use of the common fertilizer thiosulfate appeared to have great potential in phytoextraction practices since it was able to facilitate the uptake by plants of both Hg and As. Moreover, the application of a consortium of indigenous PGP bacteria (PGPB) produced a further positive effect on the plant biomass, supporting and enhancing the phytoextraction strategy, thus demonstrating their potential in a microbe-assisted phytoremediation intervention.

     

A two-year experience on 15N-urea fertilization of a corn field amended with fly ash

Soybean seedlings (Glycine max) were exposed to simulated acid rain containing sulfate ion only or a mixture of sulfate, nitrate and chloride anions, using a continuous rain generating system in a side opened glasshouse. Plants were subjected to acid rain treatment twice a week, for a 1 or 3 hr period at a rate of 2.2 or 5.0 mm hr^?1, respectively. Dry seed yield in plants treated with simulated acid rain at pH 2.0, in the three of 4 experiments conducted over a 3 yr period, was significantly less than that at pH 3.0 or higher. Simulated acid rain treatment at pH 3.0 or higher did not significantly affect yield compared to pH 5.6; however, plants exposed to simulated acid rain at pH 4.0 tended to yield more than those treated with pH 5.6 rain. Based on the current 3 years of research in which results from 4 experiments were combined, rain acidity at current levels in Japan would not directly affect seed production of selected cultivars of soybean.     

Polycyclic Aromatic Hydrocarbons (PAHs) Slurry Phase Bioremediation of a Manufacturing Gas Plant (MGP) Site Aged Soil

Bench scale tests have been carried out in order to investigatebioremediation feasibility of a Manufacturing Gas Plant site(Bovisa Gasometri – MI – I) aged soil, highly contaminated bypolyaromatic hydrocarbons (PAHs) and mineral oils. Biodegradationstudies were carried out at 22 °C in a slurry system reactor, with a solid to liquid ratio of 10% w/w. Three testswere performed, over a period of 23, 24 and 91 days respectively.In the first test, only soil and water were put into the system.In the second test, microbial activity was inhibited to evaluatethe amount of abiotic losses. In the third test, macronutrientswere added to the reactor; bioaugmentation was also carried outby an inoculum of autochthonous PAH-degrading microorganisms. Saturated hydrocarbons, PAHs, transformation products, heterotropic and PAH-degrading bacteria and fungi were monitored.Tests showed that high removal efficiency could be obtained following 23 days of treatment for all PAHs, including high molecular weight compounds. Abiotic losses were an importantprocess contributing to concentration abatement in soil, especially in the first phase of the treatment. Lag time lackfor all polyaromatic hydrocarbons revealed that autochthonousmicroorganisms were well adapted to these contaminants; bioaugmentation did not seem to speed up the process. The higherremoval rate and efficiency for high molecular weight PAHs obtained in the third test suggested that nutrient addition could play an important role in the biodegradation process ofthese compounds, whereas it did not significantly modify total(abiotic + biotic) removal of light compounds.     

A prioritised inventory of crop wild relatives and wild harvested plants of Tunisia

Genetic Resources and Crop Evolution - An inventory of crop wild relatives (CWR) and wild harvested plants (WHP) occurring in Tunisia, based on the integration of the last available floristic...     

Correction to: A prioritised inventory of crop wild relatives and wild harvested plants of Tunisia

Genetic Resources and Crop Evolution -