Full text
| |
| Author(s): |
Felipe Ibañez de Santi Ferrara
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) |
| Defense date: | 2010-10-13 |
| Examining board members: |
Heloiza Ramos Barbosa;
Marcos Pereira Marinho Aidar;
Welington Luiz de Araujo;
Marcia Pinto Alves Mayer;
Vanildo Silveira
|
| Advisor: | Heloiza Ramos Barbosa; Eny Iochevet Segal Floh |
| Abstract | |
Aiming to evaluate the influence of the organic fertilization, applied to sugarcane, on the physiology of endophytic nitrogen-fixing bacteria, 36 isolates of plants submitted to organic and conventional fertilization or not fertilized (control) were identified and studied. Results showed that the major part of the strains belong to the Enterobacteriaceae family (75%). The excretions of amino acids, polyamines, IAA and ethylene substances chosen as indicators of the action of the treatment were evaluated in the 36 strains. The release of amino acids was significantly higher in cultures of bacteria isolated from organic treated plants and the production of ethylene was produced in greater amounts by strains isolated from control plants. Seven isolates, different from the 36 tested for the release of plant growth promoters, were identified as Rhizobium strains through 16S rRNA, recA and gapA sequences. Three strains were identified as Rhizobium trifolii, Rhizobium etli and Rhizobium hainanense. This genus was not described as endophytic of sugarcane previously. (AU) | |