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Considering the importance of sage and the affirmative effects of organic sourced fertilizers on plant health and agronomic attributes, we designed to compare the effects of chemical and organic fertilizers on some quantitative and qualitative traits of sage grown under field conditions and climate chamber. This study was conducted to determine the effect of organic manures on sage quality to find the better sustainable fertilization practice for sage cultivation under pot-based experiment and field conditions. In this context, three different organic manures as sheep (SM) (5, 7.5, 10, 12.5 t ha−1), chicken (CM) (5, 7.5, 10, 12.5 t ha−1), and vermicompost (VM) (0.5, 1, 1.5, 2 t ha−1) with a control (no manure) and conventional fertilizer (0.15 t ha−1 ammonium sulfate (AS) and 0.12 t ha−1 diammonium phosphate (DAP)) were used in both experiments. Regarding the parameters considered for analysis based on the two-cuttings, we have estimated some agronomic attributes including plant height, branch number, fresh weight, and dry weight, as well as essential oil yield and compounds in sage seedlings. Accordingly, we have observed that the 1st cutting was superior in essential oil (EO) amount (0.90–2.08%), and also the 1st cutting had a high fresh and dry herb weight (61.62–226.44 and 29.78–99.67 g plant−1) under field condition. However, the 1st cutting was superior in EO amount (0.41–1.87%), and the 2nd cutting had also a high fresh and dry herb weight (4.94–16.78 and 1.23–3.58 g plant−1) in pot experiments. In addition, manool (ranging from 5.24 to 40.61%) was identified as the predominant compound whereas α-thujone and camphor were the other main compounds in both experimental conditions. Highest total fresh and dry weight were obtained from plants grown with IOF, VM3 (1.5 t ha−1), and VM4 (2 t ha−1) in pot experiments, while CM4 (12.5 t ha−1) application yielded the highest total fresh and dry weight under field conditions. In addition, sage plants treated with SM at a rate of 7.5 t ha−1and 12.5 t ha−1 accumulated the higher content of essential oil under field condition. On the other hand, CM2 (7.5 t ha−1) and CM3 (10 t ha−1) treatments increased essential oil content in pot experiments. Also, the highest content of manool, a major compound, was observed at SM and VM applications in pot and under field conditions. Correlation and PCA analysis showed that field experiment conditions had higher correlation compared to pot experiment. The present study clearly indicated that chemical fertilizer could be replaced by organic fertilizers due to the higher positive impacts on herb and essential oil yield. [ABSTRACT FROM AUTHOR]

Purpose: This field study was performed to assess the variation in chemical and agronomic properties and total and extractable concentrations of heavy metals in soils fertilized with regulated doses of urban sewage sludge (USS) for 6 consecutive years in the framework of an agronomic treatment program. Materials and methods: Chemical and agronomical properties, total contents and extractable concentrations of Cd, Cr, Cu, Hg, Ni, Pb and Zn were determined in agricultural soils treated with USS for 6 consecutive years, agricultural soils cultivated using mineral fertilizers and uncultivated soils representative of the local geochemical background. Results and discussion: USS application caused a decrease in pH and an increase in extractable concentrations of Cr, Cu, Pb and Zn. No organic carbon, total nitrogen and total phosphorus enrichment trend was observed in the treated soils due to biodegradation of the organic compounds supplied by USS. The decomposition of USS organic matter was presumably the main process responsible for the pH decrease in the USS-fertilized soils. There was no heavy metal accumulation in treated soils, and total heavy metal contents were below the corresponding maximum threshold concentrations set by European and Italian legislation. Increased availability of Cr, Cu, Pb and Zn was found in treated soils due to an increase in their extractable concentrations in the treatment period. Conclusions: The results of this study suggest that the environmental risks related to the accumulation and availability of heavy metals in agricultural soils fertilized with USS are limited when treatment observes recommended doses in agronomic treatment programs. [ABSTRACT FROM AUTHOR]