The increasing infection of Cryptococcus species and Tricosporon asahii emerged in clinical patients who were immunocompromised. They usually induce lung, skin, brain and systemic infection. Morbidity and mortality of immunocompromised patients are higher than normal healthy people. Cryptococcus neoformans var. grubii ¡]serotype A¡^ infections were reported in clinical cases predominantly and they were isolated from birds¡¦ droppings in large amount. Cryptococcus neoformans var. gattii ¡]serotype B, C¡^ had a natural life in plants, especially Eucalypticus trees. Isolations from other trees were reported increasingly in the tropical and subtropical areas. Comparing to Cryptococcus species, Tricosporon asahii is the normal mycoses of soil. In this study, we performed an environmental investigation concerning Cryptococcus species and Tricosporon asahii in Southern Taiwan. 120 droppings of racing pigeons and 114 samples from Eucalypticus trees were obtained. The results revealed that 30 Cryptococcus neoformans were isolated from racing pigeons¡¦ droppings ¡]25%¡^, as well as 4 Cryptococcus laurentii ¡]3.3%¡^ and 2 Cryptococcus albidus ¡]1.7%¡^. In addition, 25 Tricosporon asahii ( 20.8% ) were isolated from droppings of racing pigeons. But, none of Cryptococcus species or Tricosporon asahii is isolated from Eucalypticus trees ¡]0%¡^. All of Cryptococcus neoformans isolated from pigeons¡¦ droppings were var. grubii ¡]serotype A¡^ and their drug susceptibility tests showed sensitive to Amphotericin B ¡]minimal inhibitory concentration ¡Ø0.25£gg/ml¡^ and Fluconazole ¡]minimal inhibitory concentration 2£gg/ml¡^ and Flucytosine ¡]minimal inhibitory concentration ¡Ø1£gg/ml¡^. To sum up, both Cryptococcus species and Tricosporon asahii were isolated from droppings of racing pigeons in our study, especially Tricosporon asahii in large amount. Opportunistic infection caused by these species should be given more attention to racing pigeons which have close contact with human . Intensive investigation and surveillance should be carried out in the future to provide an information for the control and prevention of diseases.

Submitted by Aelson Maciera (aelsoncm@terra.com.br) on 2017-03-30T19:00:59Z No. of bitstreams: 1 DissTBO.pdf: 1573981 bytes, checksum: e4e97b3faf18cb39cb38dffdf87ccfc6 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-17T19:48:58Z (GMT) No. of bitstreams: 1 DissTBO.pdf: 1573981 bytes, checksum: e4e97b3faf18cb39cb38dffdf87ccfc6 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-17T19:49:10Z (GMT) No. of bitstreams: 1 DissTBO.pdf: 1573981 bytes, checksum: e4e97b3faf18cb39cb38dffdf87ccfc6 (MD5) / Made available in DSpace on 2017-04-17T20:04:48Z (GMT). No. of bitstreams: 1 DissTBO.pdf: 1573981 bytes, checksum: e4e97b3faf18cb39cb38dffdf87ccfc6 (MD5) Previous issue date: 2016-08-26 / Não recebi financiamento / Microorganisms Plant Growth Promoters (MPCV) have the ability to produce compounds which stimulate plant growth by different mechanisms, such as the production of plant hormones and solubilization of minerals. Considering these aspects, this study aimed to evaluate the potential of yeast strains as plant growth promoters by producing indole acetic acid (IAA) and phosphate solubilization, and its inoculation of tomato seedlings. Six yeast strains were evaluated belonging to bank microorganisms Agricultural Microbiology and Molecular Laboratory (LAMAM - CCA, UFSCar). For the evaluation of IAA production by isolates the colorimetric method was used, modified DiMenna (1957); for quantification of tricalcium phosphate solubilization was used to colorimetric method of molybdenum blue. The test with tomato seedlings was conducted in a greenhouse with different cell concentrations of T. globosa (5S55) and with or without addition of glucose and tryptophan. The results showed that isolates of T. globosa and Rh. mucilaginosa produced IAA in the presence of tryptophan; the isolates of T. globosa and M. guilliermondii solubilized inorganic phosphate in a liquid medium. The isolate T. globosa (5S55) promoted the growth of tomato seedlings, with significant increases in the length of shoot and root. In conclusion, the isolates of T. globosa, Rh. mucilaginosa and M. guilliermondii have the potential for improving plant production by IAA production and / or phosphate solubilization; the yeast T. globosa (5S55) was shown to promote growth of tomato plants. / Micro-organismos Promotores de Crescimento Vegetal (MPCV) apresentam a habilidade de produzir compostos que estimulam o desenvolvimento das plantas por meio de diferentes mecanismos, como a produção de hormônios vegetais e a solubilização de minerais. Considerando estes aspectos, este trabalho teve por objetivo avaliar o potencial de linhagens de leveduras como promotoras de crescimento vegetal, através da avaliação in vitro da produção de ácido indolacético e solubilização de fosfato, e da avaliação in vivo através da inoculação da linhagem com melhores resultados em mudas de tomate. Foram avaliadas seis linhagens de levedura pertencentes ao banco de micro-organismos do Laboratório de Microbiologia Agrícola e Molecular (LAMAM - CCA, UFSCar). Para a avaliação da produção de AIA pelos isolados foi utilizada a metodologia colorimétrica, modificada de diMenna (1957); para quantificação da solubilização de fosfato tricálcico foi utilizada o método colorimétrico do azul de molibdênio. O ensaio com mudas de tomate foi realizado em casa de vegetação com diferentes concentrações de células de T. globosa (5S55), e com adição ou não de glicose e triptofano. Os resultados mostraram que os isolados de T. globosa e o isolado de Rhodotorula mucilaginosa produziram AIA na presença de triptofano; os isolados de T. globosa e o isolado de Meyerozyma guilliermondii solubilizaram fosfato inorgânico em meio líquido. A levedura T. globosa (5S55) promoveu o crescimento das mudas de tomate, com aumentos significativos no comprimento da parte aérea e raiz. Conclui-se que os isolados de T. globosa, Rh. mucilaginosa e M. guilliermondii apresentam potencial para a melhoria da produção vegetal através da produção de AIA e/ou solubilização de fosfato; a levedura T. globosa, isolado 5S55, mostrou ser capaz de promover o crescimento de mudas de tomate.