RESUMO
Sugarcane is a hybrid of Saccharum officinarum and Saccharum spontaneum, with minor contributions from other species in Saccharum and other genera. Understanding the molecular basis of cell wall metabolism in sugarcane may allow for rational changes in fiber quality and content when designing new energy crops. This work describes a comparative expression profiling of sugarcane ancestral genotypes: S. officinarum, S. spontaneum and S. robustum and a commercial hybrid: RB867515, linking gene expression to phenotypes to identify genes for sugarcane improvement. Oligoarray experiments of leaves, immature and intermediate internodes, detected 12,621 sense and 995 antisense transcripts. Amino acid metabolism was particularly evident among pathways showing natural antisense transcripts expression. For all tissues sampled, expression analysis revealed 831, 674 and 648 differentially expressed genes in S. officinarum, S. robustum and S. spontaneum, respectively, using RB867515 as reference. Expression of sugar transporters might explain sucrose differences among genotypes, but an unexpected differential expression of histones were also identified between high and low Brix° genotypes. Lignin biosynthetic genes and bioenergetics-related genes were up-regulated in the high lignin genotype, suggesting that these genes are important for S. spontaneum to allocate carbon to lignin, while S. officinarum allocates it to sucrose storage. Co-expression network analysis identified 18 transcription factors possibly related to cell wall biosynthesis while in silico analysis detected cis-elements involved in cell wall biosynthesis in their promoters. Our results provide information to elucidate regulatory networks underlying traits of interest that will allow the improvement of sugarcane for biofuel and chemicals production.
Assuntos
Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Plantas/metabolismo , Saccharum/metabolismo , Fatores de Transcrição/metabolismo , Aminoácidos/metabolismo , Carbono/metabolismo , Genótipo , Lignanas/metabolismo , Nitrogênio/metabolismo , Fenótipo , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Análise Serial de Proteínas , Saccharum/citologia , Saccharum/genética , Fatores de Transcrição/genética , TranscriptomaRESUMO
The aim of this study was to perform an ethnobotanical survey in some regions of Recôncavo da Bahia, Brazil, to investigate the profile of farmers and the local knowledge about Arachis hypogaea L. (peanut). We sampled 60 local peanut farmers from rural areas in the municipalities Conceição do Almeida, Cruz das Almas, Maragogipe, São Felipe, São Félix, Sapeaçú and Lage. One producer per residence was interviewed and a semi-structured interview model was used. During the interviews, seeds stored by the producers were collected for future analysis. The frequency of the answers was calculated using SAS (Statistical analysis system) software. Using an ethnobotanical approach, we were able to show that peanut cultivation is part of the Recôncavo da Bahia culture and that farmers in the area have their own knowledge about the use and management of this crop. This knowledge arose from information passed down over the years from previous generations. Similar farming techniques were used in all of the studied municipalities.
Objetivou-se realizar um levantamento etnobotânico em alguns municípios do Recôncavo da Bahia visando uma investigação sobre o perfil dos agricultores, além da caracterização do conhecimento local sobre a espécie. Foram feitas visitas a 60 produtores residentes em comunidades da zona rural dos municípios de Conceição do Almeida, Cruz das Almas, Maragogipe, São Felipe, São Félix, Sapeaçú e Lage, que têm contato direto com a cultura do amendoim, sendo entrevistada uma pessoa por domicílio, e que cultiva o amendoim. Utilizou-se um modelo de entrevista semiestruturada. No momento das entrevistas, foram realizadas as coletas de sementes armazenadas pelos produtores para serem testadas em trabalhos futuros. Foi calculada a frequência percentual de acordo com as respostas dos agricultores com auxílio do programa estatístico SAS - Statistical Analysis System. Por meio do levantamento etnobotânico, fica claro que o amendoim faz parte da cultura do Recôncavo da Bahia e que os agricultores detêm conhecimentos próprios sobre as formas de uso e manejo da cultura, oriundos de informações repassadas ao longo dos anos, vindas de gerações anteriores, levando-os a utilizarem técnicas de cultivo parecidas em todos os municípios que contribuíram com a pesquisa.