Popis: |
Seven rice varieties selected according to three cultivation seasons were examined with regard to their grain and straw production, and the chemical composition of straw. Weather conditions, fertiliser application and harvesting time were major factors affecting grain yield and straw composition. The following correlations were found: grain yield and straw length (r=0.82, p 80%). The blade retains a higher level of Si and the Si was less extractable than that of sheath. Extractable Si seemed to increase after urea treatment and this response was greatest in leaf sheath. Moreover, supplement of K to the rice land, especially to the late season rice, appeared to have a beneficial effect on yield and straw quality. |