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Significant benefit of soil organic matter (SOM) to crop productivity is scientifically well documented. The main constituents and active fractions of SOM are humic substances (HS) and phenolic compounds. Since both these two components strongly impact plant-soil relationship, it is importantly from an ecological point of view to discriminate their biological effects and relating them to their composition. In this study we compared the biological effects of HS, and the soil water soluble phenols (SWSP) on growth, antioxidant activities, carbohydrates, proteins, phenols, and vitamins of Pinus laricio callus. Each extract was assessed for the content of low molecular weight organic acids, soluble carbohydrates, fatty acids, and phenolic acids. Moreover, Fourier transform infrared (FT-IR) and surface-enhanced Raman scattering (SERS) spectroscopies were applied to study their molecular structure. The results showed that HS produced better callus growth compared to the control and SWSP. Carbohydrates decreased in presence of HS while proteins, vitamin C and E increased. In contrast, in callus treated with SWSP the amount of glucose and fructose increased as well as all the antioxidant activities. The data evidenced that HS rich in tartaric and fatty acids had beneficial effects on callus growth contrary to soil water-soluble phenols rich in aldehydes, and syringic, ferulic, and benzoic acids.

Two biostimulants, one derived from alfalfa plants (AH) and the other obtained from red grape (RG), were chemically characterized using enzyme linked immuno-sorbent assays, Fourier transform infrared (FT-IR) and Raman spectroscopies. Two doses (50 and 100 mL L-1 for RG, and 25 and 50mL L-1 for AH) of biostimulants were applied to Capsicum chinensis L. plants cultivated in pots inside a tunnel. The experimental design consisted of the factorial combination of treatment (no biostimulant, plus AH, plus RG) at three doses (zero, low, and high) and two time-course applications (at the second and fourth week after transplantation) and the effects were recorded at flowering and maturity. Both biostimulants contained different amounts of indoleacetic acid and isopentenyladenosine; the AH spectra exhibited amino acid functional groups in the peptidic structure, while the RG spectra showed the presence of polyphenols, such as resveratrol. These results revealed that at flowering, RG and AH increased the weights of fresh leaves and fruits and the number of green fruits, whereas at maturity, the biostimulants most affected the fresh weight and number of red fruits. At flowering, the leaves of the treated plants contained high amounts of epicatechin, ascorbic acid, quercetin, and dihydrocapsaicin. At maturity, the leaves of the treated plants exhibited elevated amounts of fructose, glucose, chlorogenic, and ferulic acids. Moreover, green fruits exhibited a high content of chlorogenic acid, p-hydroxybenzoic acid, p-coumaric acid and antioxidant activity, while both AH- and RG-treated red fruits were highly endowed in capsaicin. The 1H high-resolution magic-angle spinning (HRMAS)-nuclear magnetic resonance (NMR) spectra of red fruits revealed that both products induced a high amount of NADP+, whereas RG also increased glucose, fumarate, ascorbate, thymidine and high molecular weight species. Our results suggested that AH and RG promoted plant growth and the production of secondary

Since 2000 a multidisciplinary team of archaeologists, geologists and paleobotanists has been carrying out joint investigations at Ca’ Tron, a 11 km2 estate located at the northern lagoon of Venice and included in the east countryside of the ancient Venetian-Roman Altinum. During the systematic survey conducted in Ca’ Tron estate nine Roman sites were identified, three of which were excavated in extension. Two rural settlements are analyzed in this paper, both attended since Ist to IV-V th century AD, having different planimetric features and economic role: the first one was a farm with several outbuildings, the second one was specialized in breeding sheep, with a large rectangular building, interpretable as a sheepfold on the basis of comparison with the Roman “bergeries” investigated in the Crau of Arles (Provence). Particularly relevant to the understanding of economic activities were the micromorphological analysis of soil types, chemical and biological, especially to clarify the functions of spaces and rooms, and the study of the archaeozoological finds. The results of chemical analyses support the archaeological interpretation of the remains of the two Roman rural sites, and suggest that some buildings were stables for bred cattle, showing that the site is particularly rich with P and organic matter of not-vegetable origin. Analyses of the Phosphorus, Carbon and Nitrogen content of the soil, together with Elemental Ratios, were applied. Two different methods (ignition and hydrolysis with perchloric acid) were used to determine the phosphorus content: their reliability is discussed. The faunal remains studied, though not very large in number, allow nevertheless to understand the management of farm animals and the economic system within the two rural complexes. Samples from both the two sites, A and M, share the almost exclusive presence of only the main domestic stock-raising species: bovines, caprovines and swine. Animals appears to have been exploited not onl

Humic acids (HAs) extracted from soils developed under two Norwegian spruce (Picea abies, (L.) Karst) subalpine forests of northern Italy were characterized using chemical, thermal (TG-DTA) and spectroscopic (DRIFT) analyses. The samples were taken from five sites which differed in orientation (northern and southern exposure) and vegetal cover at different old age: grassland, regeneration, immature and mature stands. In general, the thermal patterns of HAs were similar (three exothermic reactions appeared around at 300, 400 and 500 degrees C) in both sites in grasslands and regeneration while a considerable modification appeared in HA from stands of different age at northern and southern exposure site. DRIFT spectroscopy confirmed the differences observed through TG-DTA analysis. In particular the main structural changes were ascribed to modification of carbonyl group and of CH stretching in aliphatic components in each HAs from different sites.