PlWRKY65影响芍药叶片响应细极链格孢菌侵染的防御通路分析OA

Leaf spot disease caused by Alternaria tenuissima is one of the main leaf diseases in the field production of herbaceous peony.Previous study has shown that PlWRKY65 could enhance the resistance to A.tenuissima infection in peony.With Paeonia lactiflora'Dafugui',virus-induced gene silencing(VIGS)technology was used to silence PlWRKY65 and then peony leaves were inoculated with the pathogen A.tenuissima in this study.Next the infection phenotype and hypersensitive response(HR)were observed.The leaves at 0,12,48 and 96 h after inoculation were sampled for transcriptome sequencing analysis,with the PlWRKY65-non-silenced plants as control.The results exhibited that the disease symptoms in the PlWRKY65-silenced group appeared at 48 h,earlier than those in the control;meanwhile the evident HR symptom appeared at 12 h in the control,ahead of the PlWRKY65-silenced group.RNA-seq results showed that at 0,12,48 and 96 h after pathogen infection,a total of 3 487,2 792,2 712 and 2 388 differentially expressed genes(DEGs)were respectively produced between the PlWRKY65-silenced group and the control.These DEGs mainly reflected the differences in the expression level of the cell wall-related genes,plant hormone signal transduction and anthocyanin biosynthesis metabolism.Compared with the control,the content of lignin,pectin,cellulose and hemicellulose-the four main components of cell wall-in the PlWRKY65-silenced group decreased significantly after pathogen infection,whereas the content of anthocyanin displayed irregular pattern.In conclusion,PlWRKY65 could enhance the resistance to A.tenuissima via mediating cell wall metabolism.