Citros genetic transformation with the transcription factor WRKY17

• Grant number: 11/22452-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2012
• End date: December 31, 2012
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Raquel Luciana Boscariol Camargo
• Grantee: Luiz Guilherme Bononi Fachini
• Host Institution: Instituto Agronômico (IAC). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Campinas , SP, Brazil

Abstract

Brazil stands out as a major producer of citrus, and in the region known as Brazilian Citrus Belt fruit produces 53% of all orange juice in the world. This region presents water deficit and the planting without irrigation predominant is only possible due to the use of the rootstock Rangpur lime, which presents an excellent response to such abiotic stress. However, with the emergence of citrus sudden death, it became necessary to obtain alternative rootstocks. Transcription factors are involved in various biological processes and can control the response of plants to varied stresses. After the identification and characterization of a transcription factor of the WRKY family (crWRKY17) in the citrus genome, more specifically in Citrus reshni, it was found that this is potentially involved in response to abiotic stresses. This work aims to obtain genetically modified plants of two varieties of citrus overexpressing the crWRKY17 gene. The overexpression of this gene can increase the tolerance to drought in these plants. The genetic transformation will be mediated by Agrobacterium tumefaciens EHA 105, containing the binary vector with the crWRKY17 gene, in addition to the reporter uiad-A (Gus) and selecting nptII genes. Epicotyls' segments of in vitro germinated seedlings of varieties: Hamlin [Citrus sinensis (L). Osb.] and Swingle [Citrus paradisi Macfad. cv. Duncan X Poncirus trifoliata (L.) Raf.] will be inoculated with the agrobacterium. The transformed explants will be selected in vitro and the new shoots will be assessed through the histochemical GUS test and by PCR technique, to confirm the insertion of the gene of interest. The transgenic plants obtained will be subsequently acclimatized in greenhouse for future studies of gene expression and interaction between transgenic scion and rootstocks.(AU)