Sampling and isolation of P. oryzae
Rice blast samples were collected between 2009 and 2016 in eight
villages from YYT, including the two villages where rice landraces were
sampled (Supplementary Information SI2, Fig. SI2.1), just before
harvest. Diseased organs (leaves or collars) were kept in paper bags and
dried at room temperature. Genetically pure isolates of P. oryzaewere obtained after single spore isolation from colonies grown from
infected plant material placed in humid chamber at 21°C for 1–2 days.
Single-spored fungal isolates were then grown on rice flour medium, as
previously described
(Silué & Nottéghem,
1990), and stored on filter paper at -20°C, as described by Valentet al. (Valent,
Crawford, Weaver, & Chumley, 1986).