The nutritional status of sulfur in rice plants grown on various field conditions different in soil fertility, fertilizers used and weather was investigated as follows.
1. The critical percentage of sulfur in rice shoot grown in a sulfur deficient field appears to be over 0.2 around 30 days after transplanting.
2. The mean sulfur contents at harvesting stage were 0.22% and 0.43% in the ear and straw, respectively and increased more in the straw by the application of ammonium sulfate.
3. The ratio of sulfur contents in the straw and ear (straw/ear) showed the increasing tendency from north to south only in the fertilized fields. But it was not as such in the percent translocation, the mean values of which were 26% and 29% in the fertilized and non-fertilized, respectively.
4. The sulfur uptake amounted to 6㎏ and 10㎏ per acre in the non-fertilized and fertilized, respectively.
5. The sulfur content was decreased in the order of leaf blade+leaf sheath, stem and ear, and was higher in the low productive field than that of high productive field.
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