Donato Mondelli

Evaluation of Atriplex Halimus, Medicago Lupulina and Portulaca Oleracea For Phytoremediation of Ni, Pb, and Zn

Suitable plant species are able to accumulate heavy metals and to produce biomass useful for non-food purposes. In this study, three endemic Mediterranean plant species, Atriplex halimus, Portulaca oleracea and Medicago lupulina were grown hydroponically to assess their potential use in phytoremediation and biomass production. The experiment was carried out in a growth chamber using half strength Hoaglands solutions separately spiked with 5 concentrations of Pb and Zn (5, 10, 25, 50, and 100 mg L−1), and 3 concentrations of Ni (1, 2 and 5 mg L−1). Shoot and root biomass were determined and analyzed for their metals contents. A. halimus and M. lupulina gave high shoot biomass with relatively low metal translocation to the above ground parts. Metals uptake was a function of both metals and plant species. It is worth noting that M. lupulina was the only tested plant able to grow in treatment Pb50 and to accumulate significant amount of metal in roots. Plant metal uptake efficiency ranked as follows: A. halimus > M. lupulina > P. oleracea . Due to its high biomass production and the relatively high roots metal contents, A. halimus and M. lupulina could be successfully used in phytoremediation, and in phytostabilization, in particular.

Chemical Composition and In Vitro Activity of Plant Extracts from Ferula communis and Dittrichia viscosa against Postharvest Fungi

F. communis and D. viscosa are perennial Mediterranean weeds that have been used for different therapeutic purposes in traditional pharmacopeia. Plant extracts were obtained from air dried D. viscosa young shoots (DvA) and F. communis aerial part (FcA) and roots (FcR) with n-hexane. The chemical compositions of the extracts were analyzed by HPLC-DAD, LC-MS (ESI) and LC-Q-TOF techniques. Two sesquiterpene lactones (inuviscolide, tomentosin) and three sesquiterpene acids (costic acid, hydroxycostic acid, ilicic acid) were identified from the D. viscosa extract, while in F. communis extracts three daucane sesquiterpenes (acetoxyferutinin, oxojaeskeanadioyl anisate, fertidin) and one coumarin (ferulenol) derivates were found. Biological activities of plant extracts were studied in in vitro experiments on the colonies and conidia of Botryotinia fuckeliana, Penicillium digitatum, P. expansum, Monilinia laxa, M. fructigena and Aspergillus spp. Extracts showed varying degree of antifungal activities on colony growth and conidia germination. The extract from FcA showed the least effect, while DvA extract had the strongest fungitoxic effects. FcRextract presented a fungitoxic effect on the colony growth, but it was not able to inhibit the conidia germination. These distinctions can be attributed to the differences in chemical composition of plant extracts.

Cocomposting of sludge from olive oil mill wastewater mixed with tree cuttings

The sludge residue from olive oil mill wastewater (OMW) evaporated in natural conditions in an open-air lagoon was cocomposted with tree cuttings (TC) in two mixtures, 48% of OMW sludge + 52% of TC (M1, C/N ratio, 30), and 58% of OMW sludge + 42% of TC (M2, C/N ratio, 26). The evolution and modification of properties occurring in the OMW sludge-TC mixtures at different stages of the composting process were evaluated by chemical analyses, including pH, electrical conductivity and contents of total organic C, total N, total extractable C and humified C fractions. Further, HAs were isolated from the mixtures by a conventional procedure based on alkaline extraction, acidic precipitation to pH 1, purification by repeated alkaline dissolutions and acidic precipitations, water washing, dialysis, and final freeze-drying. The HAs obtained were analyzed for elemental (C, H, N, S, O) and acidic functional group (carboxylic and phenolic) composition, and by ultraviolet/visible, Fourier transform infrared, fluorescence and electron spin resonance spectroscopies. Composting of the OMW sludge-TC mixtures resulted in an increase of pH and total N, ash and humified C contents, whereas electrical conductivity and total organic C, total extractable C and NH4 +−N contents and C/N ratio tended to diminish. At the initial stage of composting, HAs from the OMW sludge-TC mixtures were characterized by a marked aliphatic character, small O and acidic functional group contents, marked presence of proteinaceous materials and partially modified lignin moieties and polysaccharides-like structures, extended molecular heterogeneity, low organic free radical contents and small degrees of aromatic ring polycondensation, polymerization and humification. With increasing the composting time, a loss of aliphatic materials and carbohydrates, and an increase of oxygenation, acidic functional groups, S- and N-containing groups and aromaticity occurred in HA fractions. Chemical and physicochemical analyses of the two OMW sludge-TC mixtures and their HA components at the end of composting indicated that an adequate degree of maturity and stability was achieved by both end products, and especially for the one obtained from mixture M2.

In situ evaluation of the fruit and oil characteristics of the main Lebanese olive germplasm

BACKGROUND Very little information is available on the characteristics of the Lebanese olive germplasm. Therefore, the aim of this work was to evaluate the fruit and oil characteristics of the main Lebanese olive varieties (Aayrouni, Abou chawkeh, Baladi, Del and Soury) from two successive crop seasons (2010-2011). RESULTS All of the genotypes had medium-high oil content in the fruit, indicating their suitability for oil production; Aayrouni had particularly high values. The variety Abou chawkeh also had a high pulp/pit ratio, which is a very desirable trait in table olives. For all the varieties the values of free fatty acids, peroxide values, absorbances in ultraviolet, fatty acid composition, sterol content and composition and erythrodiol + uvaol content of the oils were within the requirements of the International Olive Councils Trade Standard for extra virgin olive oil. The only exception was for the values of Δ-7-stigmastenol in 2011 in Soury and, especially, in Baladi, which were higher than 0.5%. In some cases, stearic and arachidic acids fluctuated around the maximum values allowed. CONCLUSION The findings of this study provide a first picture of the main characteristics of olives and oils currently produced in Lebanon.

Solutions for soil fertility management to overcome the challenges of the Mediterranean organic agriculture: tomato plant case study

Regulation of organic farming allows the use of a limited range of fertilisers and soil amendments to meet nutritional needs of the plants. Before advocating alternative strategies for fertility management, performance should be evaluated. An open field experiment was conducted to study the effects of different fertilisation scenarios on tomato (Solanum lycopersicum Mill, cv. San Marzano) production and soil chemical properties. Fertilisation scenarios were based on combinations of amendments (composts and biochar) with organic and/or mineral fertilisers to balance plant nutrient requirements. Amendments were produced from agricultural and food-industry wastes available in the region. Most of the soil parameters did not vary by the end of experiment; only available phosphorus slightly increased in the treatments where organic fertilisers were applied. All treatments significantly increased yields over control and biochar alone. Different compost types showed promising results for tomato production and quality, whereas biochar did not. The study demonstrated that recycling of nutrients from on-farm or food-industry wastes might be a good strategy to increase productivity and sustainability of Mediterranean organic agriculture when integrated fertility management is adapted. However, more studies are needed to evaluate their effect in long-term experiments.

Soil Management Systems: Effects on Soil Properties and Weed Flora

A three-year experiment was conducted in order to evaluate the effects of three different soil management systems in a vineyard (organic mulch with exhausted olive pomace at 6 cm thick, weed mowing and herbicide application) on soil physicochemical characteristics and weed flora. A variety of data was collected throughout the trial, such as soil analyses, weed surveys and phytotoxicity tests. The results show that the exhausted olive pomace was able to increase the K and Mg content and exerted good control over weeds, and also had an effect on the weed flora composition. Although further research is needed, it is possible to conclude that the mode of action of the exhausted olive pomace was both mechanical (thickness of the layer) and phytochemical for the release of phytotoxic compounds (allelochemicals).