The effect of ample nitrogen fertilizer on cell-wall materials and its significance to rice blast disease.

Abstract

Ample supplies of nitrogen fertilizer in the form of ammonia reduced total carbohydrates, hemicellulose and lignin content of rice plant. There was a slight reduction of α-cellulose, but no alteration of pectic substances. Total sugar was increased according to the ammount of N supplied. At maximum level of total nitrogen in rice plant, the additional supply of nitrogen fertilizer had no effect on the reduction of hemicellulose. The hydrolysates of hemicellulose consist mainly of xylose with small quantities of arabinose and glucose. The significance of the reduction of cell-wall materials for reduced mechanical resistance to rice blast disease is discussed.