Pathogenicity of Rice Blast Fungus Magnaporthe oryzae on Brachypodium distachyon
WANG Xiao-yan1, 2; WANG Jiao-yu2,*; JIANG Hua2; WANG Yan-li2; ZHANG Zhen2; CHAI Rong-yao2; MAO Xue-qin2;QIU Hai-ping2; DU Xin-fa2; SUN Guo-chang2,*
1College of Chemistry and Life Sciences， Zhejiang Normal University， Jinhua 321000， China； 2Institute of Plant Protection and Microbiology， Zhejiang Academy of Agricultural Sciences, Hangzhou 310021， China； *Corresponding authors, E-mail: firstname.lastname@example.org； email@example.com
Abstract An inoculation method for rice blast fungus Magnaporthe oryzae to Brachypodium distachyon was developed to investigate the infection process and symptom development in comparison with those on rice (Oryza sativa) and barley (Hordeum Vulgare). M. oryzae could infect the leaves, sheathes, stems and panicles of B. distachyon and cause blast disease. Spraying conidium suspension on either whole seedlings or leaf segments led to typical symptoms on B. distachyon. During the whole seedling inoculation, the symptoms on B. distachyon leaves developed closely resemble with rice; but the lesions on B. distachyon had better uniformity in shapes and sizes than those on rice or barley. In the leaf segments inoculation, only initiate and lowdeveloped lesions could be found on rice, while normal symptoms on B. distachyon and barley. Inoculated with lowvirulent mutants of M. oryzae, B. distachyon produced lowlevel symptoms. And the symptom level of each mutant on B. distachyon corresponded well to that on rice. In addition, typical infection processes presented on B. distachyon leaves: forming melanized appressoria, penetrating into host epiderm and then forming hyphae in epidermal cells. According to these results, B. distachyon can be used as a candidate for studying fungusplant interactions and as a probable source of disease resistance.
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