Control of snow mold damage of winter wheat by snow compaction (Yuki-fumi)

Snow mold, a disease of grasses and winter cereals under snow in cold temperate regions incited by cold-adapted fungi, is characterized by the ability to grow at sub-zero temperatures but differ in eco-physiological features. We hypothesized that snow compaction (yuki-fumi) might affect the thermal conditions under snow coverage, ultimately alleviating snow mold severity. Yuki-fumi was conducted using machinery attached to a tractor in winter wheat fields for five years; yuki-fumi in midwinter or both in early winter and midwinter reduced the damage due to Typhula ishikariensis and Microdochium nivale in snowy winters. The damage by Sclerotinia borealis was minimized in the winter when snow cover occurred late in the season. Yuki-fumi reduced the number of days with continuous soil temperatures at 0 ± 0.5 °C to less than 30 days and mitigated snow mold damage, consequently improving wheat growth regardless of snow mold species. These results indicate that conditions critical for snow mold development may be manipulated through yuki-fumi, making it a cost-effective and environmentally friendly control measure against snow mold. [Display omitted] •Days with continuous soil temperatures at 0 ± 0.5 °C is an index for snow mold.•Yuki-fumi reduced the days with continuous soil temperatures to less than 30 days.•Yuki-fumi also minimized cold-loving S. borealis in the late snow cover year.•Snow compaction (Yuki-fumi) is an environmentally friendly disease control.