An overview of the transcriptional responses of tolerant and susceptible sugarcane varieties to borer (Diatraea saccharalis) infestation

• Ano de defesa: 2019
• Autor(a) principal: Mello, Uilian Stefanello de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa
• Palavras-chave em Português: Cana-de-açúcar - Doenças e pragas; Cana-de-açúcar - Melhoramento genético; Cana-de-açúcar - Resistência a doenças e pragas; Diatraea saccharalis; Melhoramento Vegetal
• Link de acesso: https://locus.ufv.br//handle/123456789/28859

Diatraea saccharalis is a threat to the sugarcane productivity. Obtaining borer tolerant varieties is an alternative method of control. Although there are studies about the relationship between the interaction of D. saccharalis with sugarcane, little is known about the molecular mechanisms that confer tolerance to sugarcane varieties. The objective of this work was to characterize the transcriptional profile of sugarcane genotypes in response to borer attack and to identify differentially expressed transcripts and genes. For that, two sugarcane varieties were analysed, RB867515 and SP80-3280, considered tolerant and sensitive to the attack of the sugarcane borer, respectively. The experiment was conducted in DIC, with three replications, in a greenhouse. Individual 2-month-old plants were infested with 20 larvae (3 rd – 4 th instar). The plant material was collected after 12 hours of borer infestation to extract the total RNA, which was sent for sequencing using the Illumina HighSeq 2500 system. The differential expression was analyzed using the abundance of reads per transcript/gene between the infested plants and the control group using the software KALLISTO version 0.43.1 and STAR version 2.7.0a, utilizing the transcripts of the SUGIT (Sugarcane Iso-Seq Transcriptome) and genes from STP (Single Tiling Path) databases as mapping references. The data were submitted to differential expression analysis using the DESeq2 1.6.3 package, implemented in R version 3.5.1 software. The differentially expressed transcripts and genes were termed to as DETs and DEGs, respectively. A total of 927 DETs and 516 DEGs were identified (FDR≤0.01) and both were annotated using similarity search. The DETs and DEGs identified are mainly related to the biosynthetic pathways of jasmonic acid (JA), ethylene (ET), defense proteins, photosynthesis and sugar/carbon metabolism. In general, RB867515 demonstrated a higher regulation of JA, ET, and defense protein genes, as well as a more expressive down-regulation of pathways involved in photosynthesis and sugar/carbon metabolism. The results will allow the study of the resistance mechanisms of sugarcane against D. saccharalis and the selection of new targets for breeding to obtain resistant cultivars.