Abstract
Recently, large scale farmland consolidation and upsizing of farming machinery have been progressing in the rice cultivation. In addition to the rice for staple food, various rice cultivations such as forage rice using a high-yield variety are conducted. On the other hand, the air temperature in summer has been increasing and it has great influence on the quality of rice. In this paper, the improve-ment of plowing practice and introduction of the under-ground irrigation system (FOEAS) mitigated the decline in quality of rice under high air temperature condition by maintaining the favorable rhizosphere environment. More-over, the nutrient balance of the soil was clarified. The sili-cic acid balance was negative in all cultivation. Silicic acid was effective for improvement of rice quality under high air temperature. Besides, this paper showed the measures to promote the aerobic decomposition of rice straw derived from cultivation of high-yield rice varieties. Finally, this paper proposed that the way of “soil-making” is not lim-ited to the application of soil amendments and soil-making fertilizers, but also comprehensive management including the machine work for the purpose of improving the rhizo-sphere environment.
