36 



O. Daikiilisira and T. Iinitseki. 



soil and the reduction can proceed so energetically in the sub-soil that all 

 the nitrate applied may be reduced within a few weeks. 



(5)- Organic matters easily available to microbes favor denitrification 

 to a large extent ; further, straw or fresh rape cakes have more influence 

 upon the reduction of nitrate than the same materials well rotten, which 

 agrees with former observations on stable manure. 



PRACTICAL SUGGESTIONS. 



(i). The Chili-saltpetre is no suitable fertilizer for plants grown in 

 paddy soil. 



(2). When Chili-saltpetre is to be used for paddy plants, organic 

 manures should not be applied along with it, hence artificial mixed fertilizers 

 composed of Chili-saltpetre and some organic substances are to be avoided for 

 paddy fields. 



(3) When however an organic fertilizer is unavoidably to be used 

 along with Chili-saltpetre for paddy plants, the former should be used only 

 in a well rotten state. 



In conclusion, the authors express their hearty thanks for valuable 

 suggestions and advice given by the Director Prof. Y. Kozai and Prof. 

 Dr. O. Loew and for the analytical service given by Assistant Mr. 

 C. Matsuoka. 



