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Introduction: The use of treated municipal wastewater (TWW) represents a relevant opportunity for irrigation of agricultural crops in semi-arid regions to counter the increasing water scarcity. Pharmaceutically active compounds (PhACs) are often detected in treated wastewater, posing a risk to humans and the environment. PhACs can accumulate in soils and translocate into different plant tissues, reaching, in some cases, edible organs and entering the food chain. Methods: This study evaluated the uptake and translocation processes of 10 PhACs by olive trees irrigated with TWW, investigating their accumulation in different plant organs. The experiment was conducted in southern Italy, in 2-year-old plants irrigated with three different types of water: freshwater (FW), TWW spiked with 10 PhACs at a concentration of 200 µg L-1 (1× TWW), and at a triple dose (3× TWW), from July to October 2021. The concentration of PhACs in soil and plant organs was assessed, collecting samples of root, stem, shoot, leaf, fruit, and kernel at 0 (T0), 50 (T1), and 107 (T2) days of irrigation. PhACs extraction from soil and plant organs was carried out using the QuEChERS method, and their concentrations were determined by high-resolution mass spectrometry coupled with liquid chromatography. Results: Results of uptake factors (UF) showed a different behavior between compounds according to their physicochemical properties, highlighting PhACs accumulation and translocation in different plant organs (also edible part) in 1× TWW and 3× TWW compared to FW. Two PhACs, carbamazepine and fluconazole, showed interactions with the soil-plant system, translocating also in the aerial part of the plant, with a translocation factor (TF) greater than 1, which indicates high root-to-leaf translocation. Discussion: Findings highlight that only few PhACs among the selected compounds can be uptaken by woody plants and accumulated in edible parts at low concentration. No effects of PhACs exposure on plant growth have been detected. Despite the attention to be paid to the few compounds that translocate into edible organs, these results are promising for adapting wastewater irrigation in crops. Increasing knowledge about PhACs behavior in woody plants can be important for developing optimized wastewater irrigation and soil management strategies to reduce PhACs accumulation and translocation in plants. [ABSTRACT FROM AUTHOR]

Kiwifruit vine decline syndrome (KVDS) is an emerging challenge related to various factors, including water stagnation, soil compaction, root hypoxia, imbalanced soil redox potential, soil nutrient imbalance and fungal pathogens, yet its definitive causes remain unconfirmed. This study compared soils and roots of healthy plants (CTRL group) and plants affected by KVDS (KVDS group) at a kiwifruit orchard (Actinidia chinensis cv. 'Zesy002') in Sermoneta (Lazio region), Italy. Our findings indicate that soil redox potential, a parameter related to soil oxidation, and soil macroporosity were significantly lower in the KVDS soils. The water table was also found to be higher in the KVDS block of the orchard, demonstrating a higher soil water content. This suggests less aeration and more water content in KVDS‐affected soils compared to the control. Root analyses showed that KVDS led to browning and decomposition of rhizodermis, decay of the central stele, detachment of the cortex, reduced cell size and the presence of starch granules in the parenchyma, with significant variations in root morphometric parameters. To mitigate KVDS, sustainable agronomic practices, including precision irrigation, green manure, compost addition and water drainage root pruning, were carried out on some KVDS‐symptomatic vines (SUST group). Molecular analyses revealed the presence of 10 fungal species from treated root plants, with Paraphaeosphaeria michotii, Fusarium oxysporum and Ilyonectria vredenhoekensis being frequently isolated from symptomatic KVDS‐affected plants but less from SUST plants. Also, Beauveria bassiana and Bacillus amyloliquefaciens, showed an effect against I. vredenhoekensis and P. michotii, and may be suitable candidates as biocontrol agents. The adoption of sustainable agronomic practices resulted in significantly more healthy plants (46% increase) by the end of the trial, demonstrating that a sustainable soil use and water management at kiwifruit orchards can mitigate KVDS through restoration of natural growth conditions. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effects of 2 soil management systems, so called 'innovative' (INN) and 'conventional' (CON), on genetic and metabolic diversity of soil microbial communities of peach and kiwifruit orchards. INN system included minimum tillage, organic matter inputs from compost and cover crops, winter pruning, and adequate irrigation and fertilisation. CON system was characterised by conventional tillage, zero organic input, empirical pruning, strong chemical fertilisation, and excessive irrigation. After 4 years of treatments, soil samples were collected in different orchard sites. In peach and kiwifruit INN orchards, average fruit yields were significantly higher than in CON. INN orchards had a significantly higher total number of bacteria. The patterns of denaturing gradient gel electrophoresis of bacterial 16S rDNA/RNA from peach orchard showed differences between soils under drip emitters and along the inter-rows, whereas those from kiwifruit orchard clearly distinguished between INN and CON for both bacteria (16S rRNA) and fungi (I 8S rDNA/RNA). Shannon's substrate diversity index, evaluated by Biolog® metabolic assay, was affected by soil treatment in peach orchard and by soil depth in kiwifruit orchard. Principal component analysis of Biolog® values clearly discriminated INN and CON soils of both orchards. The results revealed qualitative and quantitative changes of soil microbial communities in response to an innovative and sustainable soil management. Additional keywords: Actinidia deliciosa, Biolog®, DGGE, Prunus persica, soil fertility, sustainable soil management., Introduction The loss of soil quality is a process that mostly affects areas where intensive agriculture and an indiscriminate use of external energetic inputs (fertilisers, pesticides, water) are adopted (Lal [...]