A transplant can be defined as a seedling or sprouted vegetative propagation material grown in a substrate or in the field, for transfer to the final cropping site. Nurseries use a range of growing media in the production of transplants, and the quality of a substrate may be defined in terms of its feasibility for the intended use and also according to the climatic condition of the production site. Peat is the worldwide standard substrate, but because of its origin and the increasing environmental and ecological concerns, new alternatives have been proposed for organic production. Here, we reviewed these new alternatives, assuming that the proposed growing media will need to respond in a proper way to specific plant requirements while also taking them into consideration to be environmental friendly, at the same time. Appropriate composting management combined with suitable feedstock material can produce substrates with adequate properties to develop transplants. Potential added-value benefits of particularized compost have been highlighted, and these include suppressiveness or capacity for plant pathogen control, biofertilization, and biostimulation. This added value is an important point in relation to the framework of organic agriculture because the use of chemical fertilizers and pesticides is limited. Different permitted fertilizers are proposed by incorporating them by dress fertilization before planting or by foliar fertilization or fertigation during the seedling production phase. In this context, specific beneficial microorganism inoculation demonstrates better and quicker nutrient solubilization. Its inclusion during seedling production not only facilitates plant growth during the germination and seedling stages but also could bring efficient microorganisms or beneficial microorganisms to the field with the transplants. This review will help to bridge the gap between the producers of compost and the seedling plant producers by providing updated literature.

No abstract

No abstract

Pilot tests were performed with a process combination of electrodialysis and ozonation for the removal of micropollutants and the concentration of nutrients in urine. In continuous and batch experiments, maximum concentration factors up to 3.5 and 4.1 were obtained, respectively. The desalination capacity did not decrease significantly during continuous operation periods of several weeks. Membrane cleaning after 195 days resulted in approximately 35% increase in desalination rate. The Yeast Estrogen Screen (YES), a bioassay that selectively detects oestrogenic compounds, confirmed that about 90% of the oestrogenic activity was removed by electrodialysis. HPLC analysis showed that ibuprofen was removed to a high extent, while other micropollutants were below the detection limit. In view of the fact that ibuprofen is among the most rapidly transported micropollutants in electrodialysis processes, this result indicates that electrodialysis provides an effective barrier for micropollutants. Standardised plant growth tests were performed in the field with the salt solution resulting from the treatment by electrodialysis and subsequent ozonation. The results show that the plant height is comparable to synthetic fertilisers, but the crop yield is slightly lower. The latter is probably caused by volatilisation losses during field application, which can be prevented by improved application technologies.

The article reviews the current state of knowledge of the production of polyhydroxyalkanoate (PHA) biopolyesters under extreme environmental conditions.Although PHA production by extremophiles is not realized yet at industrial scale, significant PHA accumulation under high salinity or extreme pH-or temperature conditions was reported for diverse representatives of the microbial domains of both Archaea and Bacteria. Several mechanisms were proposed to explain the mechanistic role of PHA and their monomers as microbial cell-and enzyme protective chaperons and the factors boosting PHA biosynthesis under environmental stress conditions. The potential of selected extremophile strains, isolated from extreme environments like glaciers, hot springs, saline brines, or from habitats highly polluted with heavy metals or solvents, for efficient future PHA production on an industrially relevant scale is assessed based on the basic data available in the scientific literature. The article reveals that, beside the needed optimization of other cost-decisive factors like inexpensive raw materials or efficient downstream processing, the application of extremophile production strains can drastically safe energy costs, are easily accessible towards long-term cultivation in chemostat processes, and therefore might pave the way towards cost-efficient PHA production, even combined with safe disposal of industrial waste streams. However, further challenges have still to be overcome in terms of strain improvement and process engineering aspects.