A 10-fold-diluted suspension of a fertilizer paste (product name: TP, Taki Chemical, Hyogo) was tested for suppression of violet root rot of apple caused by Helicobasidium mompa in infested kuroboku soil (soil texture: L), gray lowland soil (SL, LiC) and brown forest soil (HC, SL). In pot experiments with infested soils, disease severity on apple rootstocks (Malus prunifolia var. ringo) in all soils treated with TP was lower than on those treated with tap water. These results suggested that a fertilizer paste applied to the soil surface around the trunk bases of apple trees will suppress disease in most apple orchards.
Incidence or severity of seedling rot was examined for rice seedlings grown from iron-coated seeds under various conditions or stages in pots infested with Pythium arrhenomanes to determine the best management practices. Disease incidence was significantly higher in flooded conditions than in drained. Rice seedlings were susceptible from just after germination, i.e., pigeon-breasted stage to the first-leaf stage, and became resistant to infection after the second-leaf stage. Disease severity was similar at 10-25°C when soils were flooded at different temperatures during the susceptible early stage. These results suggest that keeping the water drained from soils from germination until the first-leaf stage will control the disease on rice germinated from iron-coated seeds directly sown into flooded paddy fields.