2-Azahypoxanthine and imidazole-4-carboxamide produced by the fairy-ring-forming fungus increase wheat yield

•2-Azahypoxanthine (AHX) or imidazole-4-carboxamide (ICA) increased yield of wheat.•AHX treatment of wheat seeds significantly increased yield.•Yield increase was due to the increase in number of ears.•AHX or ICA mitigated to decrease tillers under high temperature.

Two-year field examinations to see effects of the principle components of a fungus causing “fairy rings” phenomena on lawns, 2-azahypoxanthine (AHX) and imidazole-4-carboxamide (ICA), on wheat were performed. The treatment of AHX or ICA was performed, in the early (seedling treatment, seed soaking treatment) and late (field treatment) developmental stages, and the resulting number of ears and grain weight per plant increased. AHX treatment increased the number of ears before tillering and ICA treatment increased the number after tillering. The high temperature during tillering stage in 2011 was a stress condition for wheat production in fields. The results indicated that AHX and ICA increased number of tillers and then number of ears, resulting in the increase of the grain yield even though under high-temperature stress.