Novel chitosan/alginate microcapsules simultaneously loaded with copper cations and Trichoderma viride have been prepared and characterized. Information about the intermolecular interactions between biopolymers and bioactive agents was obtained by Fourier transform infrared spectroscopy. Encapsulation of T. viride spores and the presence of copper cations in the same compartment does not inhibit their activity. Microcapsule loading capacity and efficiency as well as swelling behavior and release depend on both the size of the microcapsule and bioactive agents. The in vitro copper cation release profile was fitted to a Korsmeyer-Peppas empirical model. Fickian diffusion was found to be a rate-controlling mechanism of release from smaller microcapsules, whereas anomalous transport kinetics controlled release from larger microcapsules. The T. viride spore release profile exhibited exponential release over the initial lag time. The results obtained opened perspectives for the future use of chitosan/alginate microcapsules simultaneously loaded with biological and chemical agents in plant nutrition and protection.

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encapsulated bioactive agents applied to the Lactuca sativa L. present an innovative approach to stimulate the production of plant secondary metabolites increasing its nutritive value. calcium and copper ions were encapsulated in biopolymeric microparticles (microspheres and microcapsules) either as single agents or in combination with biocontrol agents, Trichoderma viride spores, a fungal plant growth mediator. Both, calcium and copper ions are directly involved in the synthesis of plant secondary metabolites and alongside, Trichoderma viride can provide indirect stimulation and higher uptake of nutrients. All treatments with microparticles had a positive effect on the enhancement of plant secondary metabolites content in Lactuca sativa L. the highest increase of chlorophylls, antioxidant activity and phenolic was obtained by calcium-based microparticles in both, conventionally and hydroponically grown lettuces. non-encapsulated fungus Trichoderma viride enhanced the synthesis of plant secondary metabolites only in hydroponics cultivation signifying the importance of its encapsulation. encapsulation proved to be simple, sustainable and environmentally favorable for the production of lettuce with increased nutritional quality, which is lettuce fortified with important bioactive compounds.Plant secondary metabolites (PSM) are natural sources of biologically active compounds used for a healthy diet, in traditional medicine and in a wide range of industrial applications 1 . The interest in enhancing PSM production is focused to obtain high yields suitable for commercial exploitation. Plant content of secondary plant metabolites is affected by genetic, environmental, and agronomic factors 2 . A variety of strategies (screening and selection of high-yielding cell lines, the culture of cells from various plant parts, suspension culture, induction by elicitors, metabolic engineering, optimizing media, plant growth regulators, etc.) 3 as well as treatments with microspheres loaded with chemical and biological agents 4 were used for enhancing PSM production in plant cell culture.PSM such as polyphenols encompasses several classes of structurally diverse natural products biogenetically arising from the shikimate-phenylpropanoids-flavonoids pathways. Plants require these compounds for pigmentation, growth, reproduction, resistance to pathogens and for many other functions and they represent the adaptive characteristics that were subjected to the natural selection during evolution. In comparison to the animals, plants synthesize a broader spectrum of PSM because of the immobility and impossibility to escape predators, thus they evolved such a chemically based defense against predators 5 . The number of plant secondary metabolites in fresh lettuce can be improved with the addition of desirable compounds during the growth which is readily available for the plant root uptake. Higher PSM share would also have an important impact on human health by improving the antioxidant and nutrient intake through the human diet 6,7 .With the...

Kinetics and mechanisms of copper cations and Trichoderma viride spores release from uncoated and chitosan coated alginate microcapsules were investigated. The gelation of a fixed amount of sodium alginate at different concentrations of copper ion solutions resulted in distinct kinetics and release mechanisms. The increase in copper cation concentration promoted, but the presence of the chitosan layer on the microcapsule surface and the increase in microcapsule size reduced the rate of active agent release. Fitting to simple Korsmeyer-Peppas empirical model revealed that the underlying release mechanism (Fickian diffusion or a combination of the diffusion and erosion mechanisms) depends on the copper cation concentration and presence of T. viride spores. The investigation pointed out that the proper selection of formulation variables helps in designing microcapsules with the desirable release of copper ions and T. viride for plant protection and nutrition.

Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.