Grouping Rhizoctonia solani Kuehn with non-specific esterase zymogram.

A collection of 48 isolates selected from various anastomosis groups of Rhizoctonia solani showed at least nine distinct zymograms. Isolates from rice (sasakii type), or its relatives showed zymogram Zym-1. However, other isolates in the same anastomosis group (AG-1), from other host plants (web-blight type) showed several other different zymograms. Isolates from mat rush (Igusa), rice (quasi-sheath blight) and sugar beet in AG-2-2 gave Zym-2-2A which resembled Zym-1. Other members of AG-2-2 from sugar beet gave a different zymogram Zym-2-2B. Isolates of AG-2-1 gave the pattern Zym-2-1 which was quite different from all others. Isolates from potato (AG-3), showed a characteristic zymogram Zym-3. Similar zymograms were given by some isolates of anastomosis group AG-5 which also came from potato. The zymograms roughly agreed with anastomosis groups, but sometimes were more closely correlated with ecological types. The significance of these results and their usefulness are discussed.