Oxidation of 4-chloro-3-methylphenol using zeolite Y-encapsulated iron(Ⅲ)-,nickel(Ⅱ)-,and copper(Ⅱ)-N,N'-disalicylidene-1,2-phenylenediamine complexes

The degradation of 4-chloro-3-methylphenol（PCMC）using zeolite-encapsulated iron（III）,nickel（II）,and copper（II）complexes of N,N’-disalicylidene-1,2-phenylenediamine as catalysts,in a heterogeneous Fenton-like advanced oxidation process,was studied.The physicochemical properties of the catalysts were determined using powder X-ray diffraction,thermogravimetric analysis,Brunauer–Emmett–Teller surface area analysis,Fourier-transform infrared spectroscopy,elemental analysis,and scanning electron microscopy.The effects of four factors,namely initial H2O2 concentration,catalyst dosage,temperature,and pH,on the degradation of a model organic pollutant were determined.The results show that at low acidic pH,almost complete removal of PCMC was achieved with the iron（III）,nickel（II）,and copper（II）catalysts after 120 min under the optimum reaction conditions：catalyst dosage 0.1 g,H2O2 concentration 75 mmol/L,initial PCMC concentration 0.35mmol/L,and 50 °C.The reusability of the prepared catalysts in PCMC degradation was also studied and a possible catalyst deactivation mechanism is proposed.The possible intermediate products,degradation pathway,and kinetics of PCMC oxidation were also studied.

Comparative transcriptomics reveals hidden issues in the plant response to arthropod herbivores

Plants experience different abiotic/biotic stresses,which trigger their molecular machinery to cope with them. Besides general mechanisms prompted by many stresses, specific mechanisms have been introduced to optimize the response to individual threats. However, these key mechanisms are difficult to identify. Here, we introduce an in-depth species-specific transcriptomic analysis and conduct an extensive meta-analysis of the responses to related species to gain more knowledge about plant responses. The spider mite Tetranychus urticae was used as the individual species, several arthropod herbivores as the related species for meta-analysis, and Arabidopsis thaliana plants as the common host. The analysis of the transcriptomic data showed typical common responses to herbivory, such as jasmonate signaling or glucosinolate biosynthesis. Also, a specific set of genes likely involved in the particularities of the Arabidopsis-spider mite interaction was discovered. The new findings have determined a prominent role in this interaction of the jasmonateinduced pathways leading to the biosynthesis of anthocyanins and tocopherols. Therefore, tandem individual/general transcriptomic profiling has been revealed as an effective method to identify novel relevant processes and specificities in the plant response to environmental stresses.

Changes in Olsen P in Relation to P Balance in Contrasting Agricultural Soils

Maintaining soil phosphorus （P） at adequate levels for plant growth requires assessing how the long-term P balance （viz., the difference between P inputs and outputs） results in changes in soil test P. The hypothesis that routinely measured soil properties can help predict the conversion factor of P balance into Olsen P was tested at 39 sites in agricultural areas of the Mediterranean region in Spair~. A set of soil samples from each site was analyzed for Olsen P, inorganic P （P extracted using 0.5 mol L-1 H2SO4）, pseudototal P （P extracted using 0.5 mol L-1 H2SO4 following ignition at 550 ~C）, and organic P （the difference between pseudototal P and inorganic P）. Organic and Olsen P were uncorrelated in most of the 39 soil sets, which suggests that organic P content changed little with P inputs and outputs. The slopes of the regression lines of Olsen P against pseudototal and inorganic P, which were used as two different measures of the conversion factor, ranged widely （from 0.03 to 0.25 approximately）, with their average values （about 0.10） being similar to those found in long-term experiments conducted in temperate areas. Neither conversion factor was significantly correlated with any routinely measured soil property; however, the conversion factor for inorganic P was significantly lower for calcareous soils than for noncalcareous soils. Our negative results suggest the need to isolate the influence of soil properties from that of management systems and environmental factors relating to P dynamics in future studies.