Abstract Background Canker disease caused by Neoscytalidium dimidiatum is the most serious disease that attacks the pitaya industry.One pathogenic fungus, referred to as ND8, was isolated from the wild-type red-fleshed pitaya (Hylocereus polyrhizus) of Hainan Province.In the early stages of this disease, stems show little spots and a loss MLB Sets of green color.These spots then gradually spread until the stems became rotten due to infection by various strains.Canker disease caused by Neoscytalidium dimidiatum poses a significant threat to pitaya commercial plantations with the growth of stems and the yields, quality of pitaya fruits.
However, a lack of transcriptomic and genomic information hinders our understanding of the molecular mechanisms underlying the pitaya defense response.Results We investigated the host responses of red-fleshed pitaya (H.polyrhizus) cultivars against N.dimidiatum using Illumina RNA-Seq technology.Significant expression profiles of 23 defense-related genes were further analyzed by qRT-PCR.
The total read length based on RNA-Seq was 25,010,007; mean length was 744, the N50 was 1206, and the guanine-cytosine content was 44.48%.Our investigation evaluated 33,584 unigenes, of which 6209 (18.49%) and 27,375 (81.51%) were contigs and Other Batteries singlets, respectively.
These unigenes shared a similarity of 16.62% with Vitis vinifera, 7.48% with Theobroma cacao, 6.6% with Nelumbo nucifera and 5.35% with Jatropha curcas.
The assembled unigenes were annotated into non-redundant (NR, 25161 unigenes), Kyoto Encyclopedia of Genes and Genomes (KEGG, 17895 unigenes), Clusters of Orthologous Groups (COG, 10475 unigenes), InterPro (19,045 unigenes), and Swiss-Prot public protein databases (16,458 unigenes).In addition, 24 differentially expressed genes, which were mainly associated with plant pathology pathways, were analyzed in-depth.Conclusions This study provides a basis for further in-depth research on the protein function of the annotated unigene assembly with cDNA sequences.