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A B S T R A C TOlive anthracnose is an important fruit disease in olive crop worldwide. Because of the importance of microbial phyllosphere to plant health, this work evaluated the effect of cultivar on endophytic and epiphytic fungal communities by studying their diversity in olives of two cultivars with different susceptibilities to anthracnose. The biocontrol potency of native isolates against Colletotrichum acutatum, the main causal agent of this disease, was further evaluated using the dual-culture method. Fungal community of both cultivars encompassed a complex species consortium including phytopathogens and antagonists. Host genotype was important in shaping endophytic but not epiphytic fungal communities, although some host-specific fungal genera were found within epiphytic community. Epiphytic and endophytic fungal communities also differed in size and in composition in olives of both cultivars, probably due to differences in physical and chemical nature of the two habitats. Fungal tested were able to inhibited C. acutatum growth (inhibition coefficients up to 30.9), sporulation (from 46 to 86%) and germination (from 21 to 74%), and to caused abnormalities in pathogenic hyphae. This finding could open opportunities to select specific beneficial microbiome by selecting particular cultivar and highlighted the potential use of these fungi in the biocontrol of olive anthracnose.

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Oomycetes from the genus Phytophthora are fungus-like plant pathogens that are devastating for agriculture and natural ecosystems. They are able to secrete a glucanase inhibitor protein (GIP) that inhibits the activity of endoglucanases (EGases) involved in defense responses against infection. One of the most widely distributed and aggressive Phytophthora species, with more than 1,000 host plants is P. cinnamomi. In this work we report the sequencing and characterization of a class of GIPs secreted by Phytophthora cinnamomi. The gip gene from P. cinnamomi has a 937 bp ORF encoding a putative peptide of 312 deduced amino acids. The expression of this gene was studied during growth in different carbon sources (glucose, cellulose and sawdust), by RT-qPCR and its level of expression was evaluated at five time points. The highest expression of gip gene occurred in sawdust at 8 h of induction. In vivo infection of C. sativa revealed an increase in gip expression from 12 to 24 h. At 36 h its expression decreased suggesting that a compensatory mechanism must occur in plant.

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Tubercle bacilli may survive in unstained heat-fixed sputum smears and may be an infection risk to laboratory staff. We compared the effectiveness of 1% and 5% sodium hypochlorite, 5% phenol, 2% glutaraldehyde, and 3.7% formalin in killing Mycobacterium tuberculosis present in smears prepared from 51 sputum samples. The smears were decontaminated by the tube and slide techniques. Phenol at 5%, glutaraldehyde at 2%, and buffered formalin at 3.7% for 1 min (tube technique) or for 10 min (slide technique) were effective in decontaminating sputum smears and preserved cell morphology and quantitative acid-fast microscopy results.Direct microscopy for detection of acid-fast bacilli (AFB) in sputum specimens remains the main tool for presumptive diagnosis of pulmonary tuberculosis in many countries (3). In Brazil, 70% to 80% of all pulmonary tuberculosis cases are identified by this method (3,4,5,12,13). In health units with inadequate facilities, sputum specimens are normally collected and sent as heat-fixed smears to a reference laboratory for microscopic examination. Depending on the distance and available means of transport, analysis of the sputum smears may be delayed for days. Some studies have shown that tubercle bacilli may survive in unstained heat-fixed sputum smears for at least 7 days (1,2,6,11,14) and may therefore present a potential risk of transmission of laboratory-acquired infections (9,17,19).The use of decontamination agents such as phenol (7), formaldehyde (2, 9), sodium hypochlorite (17), and glutaraldehyde (10, 11) to kill the tubercle bacilli present in smears has been documented. Decontamination of slides with these agents has improved the biosafety in transport, storage, or manipulation of slides containing sputa from patients suspected of having pulmonary tuberculosis.The decontaminating agent should kill the tubercle bacilli present in sputum smears without impacting the quantitative acid-fast microscopic results, i.e., by altering the original characteristics of the specimen or by destroying the structure of the tubercle bacilli.We compared the effectiveness of (i) 5% phenol (Merck, Darmstadt, Germany), (ii) 3.7% buffered formalin (Miyako do Brazil Indústria e Comércio Ltda., São Paulo, Brazil), (iii) 2% glutaraldehyde (Johnson & Johnson, São Paulo, Brazil), and (iv) 1% and 5% sodium hypochlorite (Miyako) for decontaminating unstained heat-fixed smears of sputum from patients suspected of having pulmonary tuberculosis. The effects of these decontaminating agents on cell morphology and on quantitative acid-fast microscopy were also studied.Sputa. Fifty-one specimens containing high numbers (grade 3ϩ) (3) of viable Mycobacterium tuberculosis bacilli obtained from outpatients who attended a health care unit (Centro de Referência Professor Hélio Fraga, Rio de Janeiro, RJ, Brazil) were studied. The specimens were transported by air to Maringá City (Universidade Estadual de Maringá, PR, Brazil) and tested within 3 days after collection. One hundred twenty-four smears from each sample (total, 6,32...

This work evaluates for the first time the relationships between copper-tolerance, -solubilization and -bioaccumulation in the entomopathogen Beauveria bassiana exposed to Bordeaux mixture, copper oxychloride or copper hydroxide. Bordeaux mixture was highly detrimental to fungus, by inhibiting the growth totally at the recommended dose (RD) and 2×RD. Copper hydroxide and copper oxychloride were found to be less toxic, reducing fungus growth, sporulation and conidial germination in an average of 29  %, 30 % and 58 %, respectively. These two copper forms were the easiest to solubilize, to precipitate and the most accumulated by B. bassiana, suggesting the involvement of all these processes on fungus copper-tolerance.

The effect of Bordeaux mixture on B. bassiana development was probably due to the toxicity of the copper ion itself, and it also induced an oxidative state in fungal cells.