Fatemeh Khelghatibana - Plant Pathology department, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
Mohammad Javan-Nikhah - Department of Plant Protection, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran
Naser Safaie - Department of Plant Pathology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran
Ahmad Sobhani - Agricultural Biotechnology Research Institute of Iran - Isfahan Branch, Agricultural Research, Educationand Extension Organization (AREEO), Isfahan, Iran
Ehsan Sari - Wheat Genomics and Pathology, Durum Wheat Breeding and Genetic Team, Crop Development Centre, University of Saskatchewan, Saskatoon, Canada

Anthracnose disease caused by Ophiognomonia leptostyla, is one of the most important and widespreadfungal disease on walnut species including Persian walnut. Knowledge of molecular defense responses, couldhelp to develop pathogen-tolerant walnut varieties. In this study RNA-seq was used to profile thetranscriptome of O. leptostylia -inoculated and mock-inoculated leaf samples of Persian walnut (cv.Chandler) at three time points: ۴۸(T۱), ۹۶(T۲) and ۱۴۴(T۳) hours post inoculation. Short reads weregenerated as ۱۰۰ PE on Illumina Novaseq ۶۰۰۰ platform. HISAT۲ and StringTie were used for mapping andtranscript assembly respectively [۲;۳]. Transcripts were annotated by sequence alignment similarity searchBLASTX to protein database UniProt, TAIR۱۰ and NCBI nr (e-value<۱e-۵). Geneontology enrichment wascarried out based on annotation results using Wego software. In sum ۳۰۹۶۱, ۴۱۲۸۳ and ۴۱۲۸۳ genes werecharacterized in T۱, T۲ and T۳ samples respectively. In contrast to T۲ and T۳ samples, GO terms in T۱ wererather of biological process than molecular function or cellular components. That means the plant hostresponses to infection increased over ۹۶hpi and ۱۴۴hpi. Differential gene expression identified ۸۹۲ and ۱۲۵۵and ۳۱۷۴ DEGs in T۱, T۲ and T۳ samples respectively (FDR < ۰.۰۰۱ LogFC=۲) compared with healthycontrol. Overall in T۱ sample the number of DEGs with decrease in expression were more than DEGs withincrease, in contrast to T۲ and T۳ samples. Further analysis revealed a long list of diverse plant defenserelated genes identified among DEGs including different transcription factors like WRKY, ERFs, NAK, PRproteins, Zinc finger and proteins and NBS-LRR proteins, serine threonine kinases, ABC transporter and aproteins involve in hormone signal transduction. These are involved in hormone signal transduction, MAPKssignaling and phenylpropanoid biosynthesis pathways and constitute a complex defense network in theresponse of walnut cv. Chandler against to O. leptostyla infection.

Juglans regia; Ophiognomonia leptostyla; plant pathogen interaction, RNA-seq; DEGs; plant defense responses; cv Chandler