PRJNA415122
RNA-seq analysis of sugarcane cultivar inoculated with S. scitamineum
Smut caused by a fungus Sporisorium scitamineum is a major disease of sugarcane that can cause considerable yield losses. Sugarcane resistance to smut has been demonstrated to be heritable although the genetic determinants of this resistance are unknown. The literature suggests that there are at least two types of resistance mechanisms in sugarcane plants. An external resistance, due to a chemical or physical barriers in the sugarcane bud, and an internal resistance governed by interaction of plant and fungus within the plant tissue. Detailed molecular studies interrogating these two different resistance mechanisms that operate in sugarcane plants infected with S. scitamineum are scarce. Here, we use light microscopy and global expression profiling with RNA-seq technology to show that S. scitamineum is recognized early and triggers a defence response in cultivar CP74-2005 that possesses internal and external defence mechanisms. Identification of genes underlying resistance in the host or pathogenicity and virulence factors in the pathogen will increase our knowledge of the sugarcane-S. scitamineum interaction and facilitate the introgression of new resistance genes into commercial sugarcane varieties. We generated 27.74 Gb Illumina HiSeq sequence from RNA extracted from replicated infected and non-infected buds from a smut resistant cultivar. A total of 860 genes were identified as differentially expressed between infected and non-infected buds using DESeq2 software. Data was analysed against non-redundant proteins using BLAST2GO annotation software. Genes involved in the phenylpropanoid pathway, cell wall biosynthesis, plant hormone signal transduction and including classical disease resistance genes were identified and shown to be involved in the response of sugarcane to infection with teliospores of S. scitamineum. In silico expression analysis of six selected genes of flavonoid biosynthetic pathway were validated by qRT-PCR.