Trifolium subterraneum cover cropping for improving the nutritional status of a Mediterranean apricot orchard.

Background: The utilization of Trifolium subterraneum L. cover crops may represent an innovative and efficient option in low-input and organic farming, especially in Mediterranean agroecosystems where low and irregular rainfall require frequent soil tillage and use of herbicides to reduce moisture losses and weed competitiveness. Since imbalances of soil macro- and micro-nutrients due to cover cropping establishment could be responsible for numerous problems in specialized orchards, such as disturbances in the normal tree growth and quality of fruits, the objective of this study was to investigate, the cumulative effects of a 3-years established T.

Long-Term Effect of Cover Crops on Species Abundance and Diversity of Weed Flora.

Cover crops are gaining in popularity as an eco-friendly tool for weed control in organic and low-input agricultural systems. A 5-year study was carried out in a Mediterranean environment (Sicily, south Italy) to (1) quantify cover crop biomass production and (2) evaluate the effects on weed soil seed bank, aboveground biomass, species richness, species composition and associations between communities. Cover crop treatments included subterranean clover ( L.

Metabolic and molecular methods to evaluate the organoclay effects on a bacterial community.

The aim of this work was to evaluate the influence exerted by two different commercial organoclays (DELLITE 43B and DELLITE 67G) on a model microbial consortium using microbial metabolic characterization with BIOLOG system and denaturing gradient gel electrophoresis (DGGE) molecular approach. The information obtained from the molecular analyses, in their complex, account for the differences in species composition induced on the reference consortium by the contact with the organoclays under study. DELLITE 43B resulted to produce a marked selective effect, stimulating the quantitative increase especially of Pseudomonas pseudoalcaligenes.

The adsorption and degradation of chlorpyriphos-methyl, pendimethalin and metalaxyl in solid urban waste compost.

To evaluate the feasibility of using compost to prepare substrates for the disposal of pesticide residues, adsorption and degradation studies were carried out on three widely used agricultural pesticides: chlorpyriphos-methyl, pendimethalin and metalaxyl. Obtained from solid urban waste, this compost has been shown to be able to adsorb high levels of chlorpyriphos-methyl and pendimethalin (85%, 100%) whereas metalaxyl was only adsorbed at a level of 37%. However, adding smectite to the compost increased the adsorption of metalaxyl by 117%.

Degradation of poly (lactic acid) and nanocomposites by Bacillus licheniformis.

Background, Aim, And Scope: The disposal problem due to non-degradable petroleum-based plastics has raised the demand for biodegradable polymers. The degradation of poly (lactic acid) (PLA) has been studied for several years, but the understanding of involved mechanisms is still incomplete. Based on our previous studies, and it is hypothesized an enzymatic involvement, the aim of this study was to continue investigations on the degradation of PLA and its nanocomposites by Bacillus licheniformis.

Effects of organoclays on soil eubacterial community assessed by molecular approaches.

The aim of this study was to evaluate the effects of the commercial organoclays, CLOISITE 30B, NANOFIL 804 and DELLITE 26C on soil eubacterial community. An enrichment test was carried out on Nutrient Broth containing the organoclay and the microorganisms previously isolated from soil. Four transfers were made, each after 7 days incubation.

Solubility and adsorption behaviors of chlorpyriphos-methyl in the presence of surfactants.

In the present work changes in the adsorption of the pesticide chlorpyrifos-methyl (CLP-m) on soil colloids induced by application of surfactants were determined using a batch equilibrium method. The surfactants used were sodium dodecyl sulphate (SDS), Tween 20, and dihexadecyldimethylammonium bromide (DHAB). The adsorption isotherms of CLP-m in aqueous medium and in surfactant solutions at concentration equal to the critical micelle concentration (CMC) fitted the Freunlich adsorption equation generally with R(2) values greater than 0.

Removal of fenhexamid and pyrimethanil from aqueous solutions by clays and organoclays.

The ability of a sodium montmorillonite (CLONa) and two commercial available organoclays having interlayer organic cations possessing different functional groups (CLO20A and CLO30B) was investigated for adsorbing two pesticides namely fenexamid (FEX) and pyrimethanyl (PMT). The two organoclays displayed a higher affinity with the pesticides than the unmodified clay, but the improvement in adsorption capacity varied according to the characteristics of the pesticide and the interlayer organic cation. FEX was adsorbed to a greater extent than PMT by both organoclays, which may be due to the higher hydrophobicity of FEX thereby indicating considerable hydrophobic interaction between the adsorbent/adsorbate systems.

Fate and degradation of triasulfuron in soil and water under laboratory conditions.

The behavior and fate of triasulfuron (TRS) in water and soil systems were examined in laboratory studies. The degradation of TRS in both buffer solution and soil was highly pH-sensitive. The rate of degradation could be described with a pseudo first-order kinetic and was much faster at pH 4 than at pH 7 and 9.

Use of model soil colloids to evaluate adsorption of phenanthrene and its mobilization by different solutions.

Inorganic (a montmorillonite; a complex of montmorillonite and aluminium hydroxide) and organo-mineral model soil colloids (a complex of montmorillonite, aluminium hydroxide and humic acid) were tested for their capacity to adsorb and desorb phenanthrene. The adsorption-desorption isotherms demonstrated that the inorganic surfaces were able to bind the pollutant, although to a lesser extent than the organo-mineral complex. The capacity of different aqueous solutions to desorb phenanthrene after 1, 7, and 30 days' contact with the model colloids was tested in order to assess their efficacy with respect to the aging effect.

Behavior of fenhexamid in soil and water.

A study was conducted to investigate fenhexamid (FEX) behavior in soil and in water. FEX proved to be rather stable at acid pH but showed slight degradation at neutral and alkaline pH. After 101 days of FEX spiking of a soil sample, 94% at pH 4, 12% at pH 7 and 23% at pH 9 of the active ingredient was still present.

Inexpensive isolation of beta-D-glucopyranosidase from alpha-L-arabinofuranosidase, alpha-L-rhamnopyranosidase, and o-acetylesterase.

Beta-D-Glucopyranosidase (betaG, EC 3.2.1.