Abstract:

In order to control N fertilizer application period and N application rates reasonably,the effect of site-specific nitrogen management (SSNM) on yield and dry matter accumulation and fertillizer-N use efficiency with rice cultivar ‘Qyoumahui1’ was studied in this article in the central areas of Guizhou Province. The results showed that the SPAD value and LCC value had extremely significant positive correlation, 36-40 was considered as the critical SPAD value, and 3.2-3.5 was the critical LCC value for N application. Compared with fertilization practice of farmer (FFP) on the condition of same N application rates, the yield of SSNM increased by 5.2%, while dry matter accumulation no significant differences between SSNM and FFP. The fertilizer-N recovery efficiency was 42.0%-144.4%, which was higher than that of FFP. SSNM was useful to control N fertilizer application period and N application rates reasonably, it had comparatively large application value in actual rice production.