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To date, the effect of Olive-Mill-Wastewater-Compost (OMWW-Compost) application combined with rhizospheric soil micro-organisms on tomato fruits biochemistry and quality under drought conditions has not been evaluated. The objective of this study is to highlight the effect of arbuscular-mycorrhizal-fungi (pure strain (M) and consortium (M')), and/or plant growth-promoting-rhizobacteria (Actinomycetes (A) and consortium of two bacterial strains (B)), and/or OMWW-compost (C), on production, quality, fruits biochemistry and antioxidant richness under drought stress. The application of CM'A and CM'B increased the carotenoid content to 94 and 79%, as well as increased the phenol content to 66 and 51% respectively, compared to the control under stress conditions. The CM'A improved total tocopherols and ascorbic acid contents in fruits to 57 and 85% respectively, compared to the control under water stress. Dual inoculation of bacteria and mycorrhizal fungi combined with OMWW-compost appears to be a suitable alternative for drought stress management. The application of OMWW-compost in combination with rhizosphere microorganisms seems to offer the hope of a relatively cheap, easy to apply and effective way to alleviate drought stress and improve tomato fruits quality. [ABSTRACT FROM AUTHOR]

Drought seriously affects the agro-physiological and biochemical functioning of plants by influencing the interactions between plants and symbiotic microorganisms. Therefore, the objective of the present study was to implement a management approach to improve tomato growth, and drought tolerance using arbuscular mycorrhizal fungi (AMF) (pure strain (M) and consortium (M′)), and/or plant growth-promoting-rhizobacteria (Actinomycetes (A) and consortium with two bacteria Z2 and Z4 (B), and/or Olive-Mill-Wastewater-compost (OMWW-compost (C)). The potential for changes in physiological (stomatal conductance, chlorophyll fluorescence, photosynthetic pigments) and biochemical (sugar, protein, hydrogen peroxide (H2O2), malondialdehyde (MDA), phenols, and antioxidant enzymes) functioning in response to water stress was analyzed. Therefore, under 35% field capacity (FC), the application of AMF (M or M′)/PGPR (A and B) amended with compost stimulated biomass and improved stomatal conductance, chlorophyll and carotenoid contents and photosynthetic efficiency to a greater extent than in uninoculated and/or unamended plants. The compost application with double inoculation including M′A (CM′A) significantly improved sugar concentrations in leaves and roots by 34% and 30% as well as enhanced antioxidant activities notably catalase (CAT), polyphenoloxidase (PPO) peroxidase (POX) and superoxide dismutase activities of about 92%, 177%, 84% and 79%, respectively. The dual inoculation together with compost (CM′A) and (CM′B) resulted in a significant reduction of H2O2 contents by 14% and 13% and MDA by 93% and 92%, respectively. The application of locally produced compost with dual combinations of bacteria can overcome the challenges of water stress by improving the physiological, biochemical and tolerance of tomato. [ABSTRACT FROM AUTHOR]

One of agriculture's most important goals is finding the proper equilibrium between sustainability and intensification of production. The exponential growth of the world population, climate variability, and soil degradation are essential factors that require the development of novel agricultural practices to achieve food security. In this context, organo-mineral fertilization has been proposed as a promising approach. Such a concept is based on novel fertilizers formulations combining organic and mineral resources features, which could simultaneously address soil fertility and health issues. The manufacturing processes of organo-mineral fertilizers (OMF) are highly versatile and revolve around the co-processing of organic and mineral matrices. OMF's peculiarity resides in using systemic methodologies for waste valorization to generate cost-effective and eco-friendly products in alignment with the bio-circular economy. Despite their advantages, OMF adoption by farmers is still not satisfactory, which could be attributed to the difficulty of accessibility and a stagnant market. This work critically reviews recent advances in the organo-mineral fertilization concept. Our review provides an in-depth understanding of the chemical, biological, and thermal methodologies used for OMF generation through mineral and organic matrices co-processing. We also discuss the positive effect of such products on the plant-soil system by focusing on the mechanism of action. Furthermore, this review scrutinizes the innovation profile of OMF based on trends of patent submission during the last 20 years. It also provides future research and development pathways based on current drawbacks and limitations of the industry. [ABSTRACT FROM AUTHOR]

The efficiency of the treatment of hospital wastewater by actinobacteria was investigated using two chemometric data analysis methods. Six strains of multi-resistant bacteria isolated from Marrakesh hospital wastewater and four strains of antagonistic actinobacteria isolated from Moroccan marine environment were characterized by fatty acids released as methyl esters by thermochemolysis-GC/MS. The hierarchical cluster analysis (HCA) and the principal component analysis (PCA) were used to correlate fatty acids (FA) distributions within strains. HCA allowed to discriminate between bacteria and actinobacteria. A lower Euclidean distance is noted for bacteria. With PCA, linear and branched-chained FAs correlated with bacteria whereas mono unsaturated FAs correlated more specifically with Gram (−) bacteria. Terminally branched-chained FAs correlated most likely with actinobacteria. A co-culture of actinobacteria and bacteria monitored during 15 days demonstrated the efficiency of the biological treatment for 2 of the 4 studied actinobacteria. The effect is more important on Gram-negative bacteria. Antagonistic actinobacteria seem to be poorly efficient against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

In Mediterranean countries, the olive oil industry generates the most important agro-industrial wastewater, which results in the production of a highly toxic sludge following effluent decantation, thus endangering the environment. In this investigation, an optimized composting process via microbial inoculation is suggested as to alleviate the toxicity of olive mill solid sludge (OMS-Sludge) through addressing its high polyphenol and lipid content. The composting assay was carried out in a bioreactor using mixtures of sludge and green wastes, with or without microbial inoculation, namely: E1 (49% sludge + 49% green waste + 2% thermophilic Inoculum), and E2 (50% sludge + 50% green waste). After 4 months of composting the inoculation had affected at significantly (p < 0.05)pH, EC and total organic carbon degradation compared to control. Furthermore, HPLC analysis revealed that OMS-Sludge composting significantly diminished the polyphenol content (95% and 85% for E1 and E2, respectively), and the lipid content (90% and 81% for E1 and E2, respectively). More importantly, microbial inoculation resulted in a significant composting efficiency, which was corroborated by a decomposition rate 65% for E1 compared to 62% for E2. In-planta assays showed that both the lipid and polyphenol contents werestrongly correlated with the sludge phytotoxicity with respect to seed germination, which was demonstrated by a substantial improvement of the germination index of Cabbage (64.44%), Turnip (86.58%) and Cress seeds (120.85%). Overall, enhancing the composting process through microbial inoculation resulted in a significant alleviation of the initial mixture phytotoxicity, and proved to be an efficient strategy for OMS-Sludge valorization. [ABSTRACT FROM AUTHOR]

One hundred twenty-two different actinomycete strains were isolated from sample collected from several depths of the Marrakech wastewater infiltration-percolation system. To evaluate the antimicrobial effect of the different actinomycetes recovered, eleven wastewater-associated micro-organisms known as human potential pathogens were used. Results showed that 44 isolates had an in vitro inhibitory effect toward at least seven of the indicator microorganisms while only five active strains inhibited all these pathogens. All five selected active isolates belonged to the genus Streptomyces. Three were identified as Streptomyces violaceorubidus. These isolates showed the broad activity spectrum against a wastewater-associated pathogenic yeast (Candida albicans), Gram-negative (Salmonella sp. CCMM B17) and Gram-positive (Staphylococcus aureus CCMM B3). These findings indicate the potential involvement of antagonistic actinomycetes in the removal of wastewater-associated pathogens. [ABSTRACT FROM AUTHOR]