1 Scientific RepoRts | 7: 2608 | DOI:10.1038/s41598-017-02566-7 www.nature.com/scientificreports Comparative de novo transcriptome profles in Asparagus ofcinalis and A. kiusianus during the early stage of Phomopsis asparagi infection Mostafa Abdelrahman 1,2 , Naoyuki suzumura 1 , Mai Mitoma 1 , Satoshi Matsuo 3 , Takao Ikeuchi 4 , Mitsutaka Mori 4 , Kyoko Murakami 4 , Yukio ozaki 5 , Masaru Matsumoto 6 , Atsuko Uragami 7 & Akira Kanno 1 Asparagus kiusianus, an important wild relative of cultivated asparagus (A. ofcinalis), exhibits resistance to stem blight disease caused by Phomopsis asparagi. However, the mechanisms underlying this resistance are not understood and no transcriptomic or genetic resources are available for this species. De novo transcriptome sequencing of A. ofcinalis and A. kiusianus stems was performed 24 h after inoculation with P. asparagi. In total, 35,259 and 36,321 transcripts were annotated in A. ofcinalis and A. kiusianus, respectively. 1,027 up-regulated and 752 down-regulated transcripts were diferentially expressed in the two Asparagus species. RNA sequencing data were validated using quantitative real-time reverse transcription PCR. Several defense-related genes including peroxidase 4, cationic peroxidase SPC4-like, pathogenesis-related protein-1-like, and jasmonic acid biosynthesis and signaling-related genes including phospholipase D alpha 1, 12-oxophytodienoate reductase and jasmonate-induced protein 23 KD were up-regulated in A. kiusianus relative to A. ofcinalis. In addition, infected A. kiusianuns exhibited a substantial increase in jasmonic acid and methyl jasmonate relative to A. ofcinalis. Peroxidase activity was signifcantly elevated in infected A. kiusianus compared with infected A. ofcinalis. Our transcriptomic database provides a resource for identifying novel genes and molecular markers-associated with Phomopsis disease resistance and will facilitate breeding and improvement of cultivated asparagus varieties. Asparagus ofcinalis L., a dioecious species of the family Asparagaceae, is an economically important horticul- tural crop worldwide because of its culinary and medicinal properties. Te total worldwide asparagus production in 2013 was approximately 7.95 million tonnes, of which 89.4% was produced in Asia, 7.2% in the Americas, 3.2% in Europe, and 0.2% in Oceania 1 . Stem blight disease caused by P. asparagi is the most serious disease for aspara- gus production in many parts of the world, including Japan, China, Australia, New Zealand, Italy, Greece, and the United States 2–4 . Disease symptoms are frst seen as small light brown lesions on the lower part of the stem. Te primary lesions subsequently become extended, forming larger dark brown oval-shaped lesions that eventually lead to complete stem desiccation and stem death 4, 5 . Stem blight disease is mainly controlled using expensive chemical fungicides. However, concerns have been raised regarding the human and environmental impacts of fungicides, as well as their impacts on the capacity of P. asparagi to survive in various environments. Terefore, production of new asparagus cultivars with strong resistance to stem blight disease has become an urgent need in the context of sustainable crop production. 1 Graduate School of Life Sciences, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan. 2 Botany Department, Faculty of Science, Aswan University, Aswan, 81528, Egypt. 3 Institute of Vegetable and Floriculture Science, National Agriculture and Food Research Organization (NARO), 360 Kusawa, Ano, Tsu, Mie, 514-2392, Japan. 4 Kagawa Prefectural Agricultural Experiment Station, 1534-1 Ayagawa, Ayauta, Kagawa, 761-2306, Japan. 5 Faculty of Agriculture, Kyushu University, Fukuoka, 811-2307, Japan. 6 Institute of Tropical Agriculture, Kyushu University, Fukuoka, 812-8581, Japan. 7 Institute of Vegetable and Floriculture Science, NARO, Tsukuba, Ibaraki, 305-8519, Japan. Correspondence and requests for materials should be addressed to M.A. (email: meettoo2000@ige.tohoku. ac.jp) or A.K. (email: kanno@ige.tohoku.ac.jp) Received: 8 November 2016 Accepted: 13 April 2017 Published: xx xx xxxx OPEN