Staged regulation and control method for nitrogen reduction and high quality of late-maturing medium japonica rice with different panicle types in high nitrogen fertilizer planting area

The invention discloses a staging regulation and control method for nitrogen reduction and excellent quality of late-maturing medium japonica rice with different panicle types in a high nitrogen fertilizer planting area. According to the method, the varieties are divided into small-panicle-type, medium-panicle-type and large-panicle-type late-maturing medium-japonica rice varieties according to panicle-type sizes by utilizing panicle-type characteristics of the late-maturing medium-japonica rice varieties with different source library types in production, and in a high nitrogen fertilizer planting area with pure nitrogen consumption (19-20) kg/mu, nitrogen is reasonably reduced by 10-11% in a nitrogen fertilizer sensitive period of each variety, and the nitrogen is reduced without reducing the yield. By means of the method, weight losing can be rapidly and accurately carried out on varieties of different panicle types, the total application amount of nitrogen fertilizer is effectively reduced, the fertilizer