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Previous issue date: 2013-01-29 / Ag?ncia Brasileira da Inova??o / Sugarcane (Saccharum spp.) is a plant from Poaceae family that has an
impressive ability to accumulate sucrose in the stalk, making it a significant
component of the economy of many countries. About 100 countries produce
sugarcane in an area of 22 million hectares worldwide. For this reason, many studies
have been done using sugarcane as a plant model in order to improve production. A
change in gravity may be one kind of abiotic stress, since it generates rapid
responses after stimulation. In this work we decided to investigate the possible
morphophysiological, biochemical and molecular changes resulting from
microgravity. Here, we present the contributions of an experiment where sugarcane
plants were submitted to microgravity flight using a vehicle VSB-30, a sounding
rocket developed by Aeronautics and Space Institute teams, in cooperation with the
German Space Agency. Sugarcane plants with 10 days older were submitted to a
period of six minutes of microgravity using the VSB-30 rocket. The
morphophysiological analyses of roots and leaves showed that plants submitted to
the flight showed changes in the conduction tissues, irregular pattern of arrangement
of vascular bundles and thickening of the cell walls, among other anatomical changes
that indicate that the morphology of the plants was substantially influenced by
gravitational stimulation, besides the accumulation of hydrogen peroxide, an
important signaling molecule in stress conditions. We carried out RNA extraction and
sequencing using Illumina platform. Plants subjected to microgravity also showed
changes in enzyme activity. It was observed an increased in superoxide dismutase
activity in leaves and a decreased in its activity in roots as well as for ascorbate
peroxidase activity. Thus, it was concluded that the changes in gravity were
perceived by plants, and that microgravity environment triggered changes associated
with a reactive oxygen specie signaling process. This work has helped the
understanding of how the gravity affects the structural organization of the plants, by
comparing the anatomy of plants subjected to microgravity and plants grown in 1g
gravity / A cana-de-a??car (Saccharum spp.) ? um planta da fam?lia Poaceae que
possui uma impressionante capacidade de armazenar sacarose no colmo, o que a
torna um significante componente da economia de muitos pa?ses. Aproximadamente
100 pa?ses produzem cana-de-a??car em uma ?rea de 22 milh?es de hectares no
mundo. Por essas raz?es, diversos estudos sobre a resposta de culturas a estresse
ambiental contemplam a cana-de-a??car. Uma mudan?a na gravidade pode ser um
tipo de estresse abi?tico, uma vez que ? capaz de gerar respostas r?pidas ap?s a
estimula??o gravitacional. No presente trabalho procurou-se investigar as poss?veis
altera??es morfofisiol?gicas, bioqu?micas e moleculares decorrentes da
microgravidade. Aqui s?o apresentadas as contribui??es do experimento de
submiss?o de plantas de cana-de-a??car ? microgravidade atrav?s de voo em um
ve?culo VSB-30, Plantas de cana-de-a??car cultivadas em condi??es controladas,
com 10 dias de desenvolvimento, foram assim submetidas a um per?odo de seis
minutos de microgravidade real. As an?lises morfofisiol?gicas de ra?zes e folhas
mostraram que as plantas sofreram altera??o nos tecidos de condu??o da seiva e
?gua, padr?o de disposi??o irregular de feixes vasculares, espessamento de
paredes celulares, entre outras modifica??es anat?micas que indicam que a
morfologia das plantas foi substancialmente influenciada pela aus?ncia de est?mulo
gravitacional, al?m do ac?mulo de per?xido de hidrog?nio, importante mol?cula de
sinaliza??o em condi??es de estresse. Foi realizada a extra??o do RNA e o
sequenciamento do RNA atrav?s da plataforma Illumina, e estas sequencias est?o
sendo analisadas. Foram tamb?m observadas altera??es nas atividades
enzim?ticas, com aumento na atividade de super?xido dismutase em folhas e
redu??o da atividade de super?xido dismutase e ascorbato peroxidase em ra?zes.
Assim, estes resultados permitem concluir que a altera??o da gravidade foi
percebida pelas plantas de cana-de-a??car e o ambiente de microgravidade
desencadeou altera??es associadas a um processo de sinaliza??o por meio de
esp?cies reativas de oxig?nio em condi??es de estresse. O presente trabalho
auxiliou, portanto, a compreender como a gravidade interfere na organiza??o
estrutural das plantas, atrav?s da compara??o da anatomia de plantas submetidas ?
microgravidade e plantas crescidas em gravidade 1g
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12603 |
| Date | 29 January 2013 |
| Creators | Silva, Helaine Cristiane |
| Contributors | CPF:13451112825, http://lattes.cnpq.br/4808910380593455, Lima, Jo?o Paulo Matos Santos, CPF:79332021368, http://lattes.cnpq.br/3289758851760692, Calsa Junior, Tercilio, CPF:17417313809, http://lattes.cnpq.br/2775650529232362, Scortecci, K?tia Castanho |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Bioqu?mica, UFRN, BR, Bioqu?mica; Biologia Molecular |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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