日本水稻保优栽培中的氮肥施用技术研究

利用日产的米质测定仪分析日本优质稻米品种(“越光”为代表)，发现稻米品质主要与其粗蛋白和直链淀粉含量有关。粗蛋白含量＜6.9%，直链淀粉含量＜20%的稻米为优质稻米。对日本关东地区各类土壤上的水稻栽培技术研究结果，则表明水稻保优栽培的关键是控制氮肥的施用量，尤其是在作穗肥施用时，应少施或不施氮肥。另外，不同类型的土壤对稻米品质也有一定影响。因此，要达到水稻保优栽培的目标，在栽培技术上要改变传统的施肥方式，要增加土壤有机质，改善栽培环境。

STUDY ON NITROGEN FERTILIZER APPLICATION IN RICE CULTIVATION ENSURING QUALITY RICE PRODUCTION IN JAPAN

The rice quality of some Japanese rice varieties producingquality rice such as “Kushihigari” etc. was analysed by use of rice quality meter made in Japan. The results indicated that rice quality was mainly related to the contents of crude protein and amylose , and the rice with crude protein content below 6.9% and amylose content below 20% is quality rice. In the meantime , the rice cultivation techniques practiced on some kinds of soils in Japan were investigated , and the results showed that the key of rice cultivation ensuring quality rice production consists in controlling the amount of nitrogenous fertilizer applied，especially no or less N fertilizer should be applied as panicle-promoting fertilizer; in addition, different types of soils also have some effects on rice quality. It is suggested thereby that the traditional fertilization method should be changed and cultivation environment should be improved through increasing organic matter in soil for ensuring quality rice production.