Sulfur nutrition of rice

Abstract

A solution culture experiment established critical sulfur contents or critical N: S ratios for sulfur deficiency of rice. Shoot dry weight increased linearly with increased lOgarithmic concentration of sulfur in culture solution. Two critical sulfur contents (or N: S ratios) in plant tissues were defined: critical sulfur content required to obtain maximum dry weight (DC100) and critical sulfur content required to obtain 50% of the maximum dry weight (DC50). The critical sulfur contents (DC100) in straw varied from 0.16% at tillering stage to 0.06% at maturity. Sinsle sulfur analysis was considered a better diagnostic tool than N: S ratio because the latter's analysis is more costly. When non-sulfur fertilizers and demineralized water were applied, sulfur deficiency was induced in potted plants on Lipa clay loam, which is not considered sulfur deficient. This experiment demonstrated the importance of sulfur supply in irrigation water as a sulfur source. Differences in natural supply of sulfur were illustrated for pot and field experiments. © 1979 Taylor & Francis Group, LLC.