PROBLEM TO BE SOLVED: To provide a material for suppressing the occurrence of soilborne disease having high occurrence-suppressing effect on Chinese cabbage rootgalls which is brassicaceous plant disease injury and Brassicaceae rootgallses such as cabbages root galls and free from environmental pollution and to provide a method for suppressing the occurrence.SOLUTION: The material for suppressing occurrence of soilborne disease is produced by carrying out carbonization treatment of a bulb part which is an onion piece in a carbonization furnace at &ge500°C and &le900°C or by carrying out carbonization treatment of an epidermal part which is an onion piece in the carbonization furnace at &ge300°C and &le500°C. After carbonization treatments of the bulb part and the epidermal part are separately carried out, these treated materials may be mixed to produce the material for suppressing occurrence of soilborne disease. The material may be produced by further adding 5-20 wt.% additive such as potassium carbonate which is permeated into the tissue of onion piece in a solution state and evaporated at carbonization treatment temperature of the onion piece to the onion piece to permeate the potassium carbonate into the tissue of the onion piece and heating the onion piece containing the potassium carbonate in the furnace to carbonize the onion piece while evaporate the additive.COPYRIGHT: (C)2008,JPO&INPIT【課題】 アブラナ科植物病害であるハクサイ根こぶ病、キャベツ根こぶ病等のアブラナ科根こぶ病に対して発病抑制効果が高く、環境汚染のない発病抑制資材および発病抑制方法を提供する。【解決手段】 玉葱片である鱗茎部分の場合は500℃以上900℃以下の温度にて炭化炉で炭化処理を実行し、表皮部分の場合は300℃以上500℃以下の温度にて炭化炉で炭化処理を実行し、土壌病害発病抑制資材として生成する。鱗茎部分と表皮部分とを別々に炭化処理した後に混合せしめても良い。さらに、溶液状態において玉葱片の組織内に浸透し玉葱片の炭化処理温度において蒸発する炭酸カリウムなどの添加剤を重量比で5%~20%添加して玉葱片の組織内に浸透させておき、炉中で加熱することにより、添加剤を蒸発させつつ玉葱片を炭化させて生成しても良い。【選択図】図2
