Abstract
1) The effects of chloropicrin, DD (Dichloropropan-Dichloropropylene) and EDB (Ethylene Dibromide) as soil fumigant were compared on the soil of continuous cropping field of upland rice. The injury on upland rice caused by its continuous cropping soil were almost removed by fumigation with chloropicrin, and diminished remarkably with DD, but not affected with EDB inspired in the soil. 2) The greater the amount of chloropicrin or DD, the greater their effect, in the range of the amount from 0.5 cc to 3 cc per 900 cm2 in field. 3) The injury was recognized to be removed by steam steriligation at higher temperature than 80°C for 20∼30 minutes. 4) It seems that in the case of continuous cropping the growth of upland rice was promoted by soil-acidification, but was nearly unaffected by application of such elements as Fe, Mn and Mg.
