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In tropical countries such as Brazil, there is not enough information about microbial contaminants in indoor environments with air conditioning systems. Microbial monitoring of such environments is important for the quality of human life. The aim of this work was to assess the fungal genera and bacterial morphotypes occurring in such environments. Air samples were taken indoors and outdoors from a public auditorium, a hospital, a company and

Drosera villosa var. villosa A. St.-Hil is a carnivorous plant that grows in Brazilian flooded soils very poor on nutrients, including low levels of N. Under these conditions, the plant shows vigorous growth, low root number, low number of captured prey (less than 50%) and a great assemblage of bacteria associated with the roots and leaves that grow in N-free medium. These preliminary results have led us to investigate the number of colony forming units (log CFU) in the roots (rhizosphere and endorhizosphere) and leaves (phyllosphere and endophyllosphere) of D. villosa var. villosa by the tenfold serial dilution technique in two N-free culture media. The results showed that the phyllosphere had 6.65 log CFU g dry leaf -1 and the rhizosphere 6.47 log CFU g dry soil -1 , with the lowest value detected in the endophyllosphere (4.39 log CFU g dry leaf -1 ). Sixty-three different bacteria morphotypes were isolated from the surface and interior of the roots and leaves and the amplification of the DNA with specific primers detected the nifH gene in 34 of those strains. The DNAs of the 34 strains were compared by the BOX-PCR technique and a great diversity was observed, with the bacteria clustering at a final level of similarity of only 12%. The strains were also submitted to the partial sequencing of the 16S rRNA gene and several genera of N 2 -fixing bacteria were detected, including Bacillus, Burkholderia, Methylobacterium, Paenibacillus, Pseudomonas and Sphingomonas.

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