The Effect of Precision Nitrogen Topdressing Decision on Winter Wheat

摘要

Topdressing in the growth period is the key to high yield of wheat. So how to use the rapid detection technique to realize scientific and real-time topdressing for lower fertilizer application and higher use efficiency of fertilizer is critical to agricultural development. The aim of this study is to investigate the effect of fertilization as affected by different topdressing recommendations. In this study, field experiments are conducted at Xiaotangshan Precision Agriculture Demonstration Base in Beijing, using commonly-used rapid detection equipment. The experimental results are summarized as follows: Variable rate fertilization based on nitrate nitrogen level in soil and grower's uniform fertilization are basically same in fertilizing amount but the former produces higher yield of 320 kg/ha; high rate application based on low measured NDVI value in the reviving stage leads to highest fertilizer productivity at 19.3 kg/ kg, with an increase of 10.4 kg/ kg compared with grower's uniform fertilization; in terms of profitability, high rate application based on low measured NDVI value in the reviving stage produces highest profit of 12,649 yuan/ha, while high rate application based on high measured SPAD value and high measured NDVI value in the reviving stage produce lowest profits of 9,358 yuan/ha and 9,775 yuan/ha respectively.