Citrus canker is a disease that affects the major types of commercial citrus crops. Xanthomonas citri subsp. citri, the etiological agent, reaches to mesophyll tissue through the stomata and afterward induces cell hyperplasia. Disease management has been based on both tree eradication and copper spray treatment. Overuse of copper for control of bacterial citrus canker has led to the development and prevalence of copper-resistant strains of Xcc. Several genera of both soil-and plant-associated bacteria became powerful tools in sustainable agriculture for control of Xcc and reduction of citrus canker disease severity. In this chapter we present bacteria able to interfere with quorum sensing as well to display antibacterial activity against Xcc by production of secondary metabolite. These bacteria may represent a highly valuable tool in the process of biological control and offer an alternative to the traditional copper treatment currently used for the treatment of citrus canker disease, with significant environmental, economic, and health implications worldwide.

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Daily composting has been identified as the best method for final disposal of carcasses, but the potential risk of pathogen transmission seriously limits its use. In this study we assessed the microbiological quality and biosafety of a compost produced in an experimental unit of daily mortality composting at Universidade Estadual Paulista (UNESP), Brazil. We know that mature compost presents a good composition of the most important agricultural chemical components and also the aqueous solutions do not inhibit the Solanum lycopersicum (tomato) and Lactuca sativa (lettuce) germination as well its development. To study the microbiological safety, samples were evaluated to determine the presence of coliforms, Salmonella sp, and several soil-borne phytopathogenic fungi (Rhizoctonia spp, Fusarium spp, Pythium spp, Phytophthora spp). These evaluations were carried out using selective and differential microbiological culture media. The composition of bacterial population in mature compost was also determined by the 16SrRNA gene sequencing in the Illumina System. The presence of STEC, EHEC, and EPEC pathogenic bacteria E. coli genes of virulence was not verified by molecular techniques. Salmonella and phytopathogenic fungi presence were negative. Coliform levels were 1160 UFC/kg, and the most common bacteria observed by 16S rRNA gene were from Firmicutes and Proteobacteria phylum. The results show that a daily mortality composting method is effective to reduce pathogenic microorganisms but it does not terminate all of them. Thus it can be used as fertilizer, except to crops intended for human or animal direct consumption. Additional tests must be performed to assure the absence of some pathogens such as viruses.

Introduction: Daily and outbursts mortality composting have been identified as one of the finest methods for final disposal of animal corpses, but the probable threat of pathogens transmission truly limits its use. Materials and Methods:  In this study we evaluated the quality and microbiological biosafety of a compost produced in daily mortality experimental unit composting at the Universidade Estadual Paulista in the state of Sao Paulo, Brazil. Settled compost sample was evaluated in order to determine the presence and counting of coliforms and Salmonella sp. and the pathotypes of E. coli STEC, EPEC and EHEC using culture and molecular techniques.  The occurrence of frequent soil borne phytopathogenic fungi was also estimated using selective and differential microbiological culture media. Results and Discussion: The occurrence of pathogenic E. coli, Salmonella sp and phytopathogenic fungi were negative. Coliforms level was 3.05 log10/g. Concussions: The results showed that daily mortality composting method is effective to reduce pathogenic microorganisms, however, in order to add the product on crops or plants such as vegetables that are for direct human consumption, additional tests must be performed to assess the presence of viral pathogens and endospores forming bacteria.