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•Nanocomposites reduced TSS by 95%.•Transportable aerated cells were constructed for the treatment of winery wastewaters.•Removal rate of COD reached 95%.•The maximum loading was 8.66kg COD m3d−1.•The integrated system is the key for successful treatment of winery wastewater.

Abstract: Twenty-nine plant extracts of local species were evaluated for their potential as a source of bioactive ingredients with significant acaricidal activity that could lead to the development of new and safe bio-acaricides. The crude extracts (70% ethanol) of these plants were tested for their acaricidal activity against the carmine spider miteTetranychus cinnabarinus in a bioassay under controlled conditions. Mortality, repellency, and the number of eggs laid were measured. Extracts fromEucalyptus camaldulensis andInula viscosa caused more than 25% mortality. Sixteen plant extracts showed significant repellency compared with the control. The six best extracts, resulting in more than 75% repellency, were fromAllium sativum, Capparis spinosa, Cupressus sempervirens, Lupinus pilosus, Rhus coriaria andTamarix aphylla. Extracts from 16 plants were found to cause a significant reduction in the number of eggs laid compared with the control. The greatest reduction was achieved by extracts fromC. spinosa, Cyperus rotundus, E. camaldulensis, L. pilosus, Punica granatum, R. coriaria andT. aphylla. A relatively negative fit was found between the mean number of repelled mites and the number of eggs laid (r=−0.65), which might indicate that most repelled mites were unable to lay eggs before leaving the leaf discs of the bioassay. Our results show that several plant extracts have good potential for acaricidal activity and are worth further investigation.

The potential of rhizosphere microbes isolated from common reed [Phragmites australis(Cav.) Trin. ex Steud] plants grown in a subsurface‐flow constructed wetland to biomethylate selenate or selenite was studied in liquid cultures under controlled conditions. Total mean percentages of volatilized Se from half‐strength Hoagland culture solutions (low C content) supplemented with selenate or selenite and inoculated with cultured rhizosphere microbes after 15 d of incubation were 7.9 and 49.1%, respectively. There was a relative best fit (r= 0.87) between total number of rhizosphere and cultured microbes and the percentage of volatilized Se in Hoagland solution after 15 d of incubation. However, when the same microbes were cultured in tryptic soybean broth (TSB) medium (high C content), the percentages of volatilized Se from selenate and selenite were 1.3 and 1.9%, respectively. The volatilization percentages of Se from selenate or selenite in culture solutions inoculated with rhizosphere suspension instead of cultured rhizosphere microbes were very low (1.2–3.0%) in both cultivation media. In all experiments, selenite was volatilized significantly (p< 0.05) in higher amounts by cultured rhizosphere microbes after 15 d of incubation compared with selenate. Dissolved biomethylated dimethylselenide (DMSe) in water samples taken from the subsurface‐flow bed was determined by purging with helium. The DMSe in water samples was indirectly detected up to 2.4 μg Se L−1, which indicates that part of the produced DMSe was dissolved in the matrix before being released into the atmosphere. Our results show that rhizosphere microbes isolated from common reed plants have a high potential of Se biomethylation and volatilization from selenate and selenite.

Biological control of the western flower thrips (WFT)Frankliniella occidentalis, using the entomopathogenicMetarhizium anisopliae-7(M. a-7) strain was studied in three consecutive seasons under greenhouse conditions. Cucumber plants infested with WFT were sprayed with spore suspension of the fungusM. a-7(0.5 g m-2), or the soil was treated with dry powder of the fungus (0.5 g m-2); the control was without fungus application. In the 1997 spring experiment, when the cucumber plants were initially infested with only three or four insects per leaf, the spore suspension spray caused a significant reduction in growth of the thrips population compared with the other treatments and the control. However, in the 1997 summer experiment, when the plants were initially heavily infested with WFT (10–15 insects per leaf), the spray treatment caused only a modest reduction in WFT population growth, and only after 4 weeks of treatment was the reduction significant. In the 1999 experiment, with a low initial WFT population of three or four insects per leaf, the spray treatment was effective in reducing the population growth to a lower level than in the other treatments or control. TheM. a-7strain was found to be effective in reducing the population growth of WFT under greenhouse conditions, particularly when the initial thrips population was low to moderate.

The potential of rhizosphere and bulk soil microbes to volatilize selenate, selenite, and selenomethionine was studied in liquid cultures under controlled conditions. Microbes cultured from the rhizosphere of bulrush (Scirpus robustus) plants showed higher Se volatilization than those from bulk soil of a flow‐through, constructed wetland area contaminated with selenite. The data show that bacteria are the dominant microbes involved in Se volatilization; fungi contribute relatively little to this process. Bactericides significantly decreased both Se volatilization and the number of culturable bacteria in rhizosphere cultures compared to an untreated control. In the absence of added C, Se volatilization was greatest from selenomethionine, then selenite, then selenate. Aeration substantially increased the percentages of Se volatilized from rhizosphere soil cultures to which no C was added. Up to 95, 21, and 3% of the Se was volatilized from selenomethionine, selenite, and selenate, respectively. When both C and aeration treatments were applied to the rhizosphere cultures, the corresponding percentages changed to 20, 57, and 4%, that is, selenomethionine volatilization by rhizosphere microbes decreased when C was added while selenite volatilization substantially increased. Since selenite volatilization was the greatest when rhizosphere microbes were supplied with C and aeration, we suggest that microbes in this selenite‐contaminated wetland are adapted to volatilize Se by using C released from roots, and that Se volatilization may be enhanced by oxygen and environmental conditions provided by the plants.

Maize (Zea mays L. cv. Alize) plants were grown in a calcareous soil in pots divided by 30-µm nylon nets into three compartments, the central one for root growth and the outer ones for hyphal growth. Sterle soil was inoculated with either (1) rhizosphere microorganisms other than vesicular-arbuscular mycorrhizal (VAM) fungi, (2) rhizosphere microorganisms together with a VAM fungus [Glomus mosseae (Nicol. and Gerd.) Gerdemann and Trappel], or (3) with a gamma-irradiated inoculum as control. Plants were grown under controlled-climate conditions and harvested after 3 or 6 weeks. VAM plants had higher shoot:root ratios than non-VAM plants. After 6 weeks, the concentrations of P, Zn and Cu in roots and shoots had significantly increased with VAM colonization, whereas Mn concentrations had significantly decreased. Root exudates were collected on agar sheets placed on the interface between root and hyphal compartments. Six-week-old VAM and non-VAM plants had similar root exudate compositions of 72–73% reducing sugars, 17–18% phenolics, 7% organic acids and 3% amino acids. In another experiment in which root exudates were collected on agar sheets with or without antibiotics, the amounts of amino acids and carbohydrates recovered were similar in VAM and non-VAM plants. However, threeto sixfold higher amounts of carbohydrates, amino acids and phenolics were recovered when antibiotics were added to the agar sheets. Thus, the high microbial activity in the rhizosphere and on the rhizoplane limits the exudates recovered from roots.