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| Author(s): |
Fernanda Piccolo Pieruzzi
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) |
| Defense date: | 2009-11-24 |
| Examining board members: |
Eny Iochevet Segal Floh;
Claudio José Barbedo;
André Luis Wendt dos Santos
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| Advisor: | Eny Iochevet Segal Floh |
| Abstract | |
Ocotea odorifera is a native tree from the Atlantic Forest with recalcitrant features that is in risk of extinction because its economical exploration. Techniques based on biotecnology can be used for the conservation and reintroduction process of species in risk of extinction in their natural environment. Between these biotecnologycal techniques, the somatic embryogenesis (SE) have been used sucessfully in programs of genetic breeding and tree germoplasm conservation. However, basic studies of physiology and biochymical of the seed development and germination are necessary for the establishment of efficient protocols of SE. Thus, these condictions in vivo can be recriated in vitro. The aim of this work was to evaluate the variations in the endogenous content of amino acids, polyamines, IAA, ABA and protein markers throughout the seed germination of O. odorifera seeds. The seeds were germinated on vermiculite substrate at 27°C and 16h of photoperiod and collected after 0, 15, 30 e 45 days of sowing. It was observed that: a) the amino acids content increased troughout the germination process. Asparagine was the highest content sighted and prevailed during the period studied. Methionine and ornithine, polyamines precursors, and tryptophan, IAA precursor, increased troughout germination process; b) the total PAs content decreased in the last 15 days of evaluation. At the same period, conjugated PAs showed an increase, indicating a relation between conjugation and avalability of polyamines inside the cells; c) the Put/(Spm+Spd) relation decreased while the Spm was the most abundant free PA observed at the end of the period analyzed indicating a relation between Spm and celular elongation; d) IAA increased during all the process while a decrease of ABA was sigthed; e) protein content decreased troughout the period observed. The proteic profile didnt change a lot between the stages. Os perfis protéicos diferiram pouco entre os estádios analisados. Entretanto, foi observada variação significativa na abundância (% de volume) em 39 spots, que foram definidos como marcadores do processo germinativo. Among them, could be include 26 that decreased and 2 that decreased its abundances troughout the germinative process, 10 that both increased and decreased throughout the period analyzed and just 1 exclusive from mature seed. These results open perspectives to avaliation of fundamentals parameters to optmization of ES protocols and allow a better comprehension about the edogenous variation of the differents compounds citeds in the process of O. odorifera seeds germination. (AU) | |