Abstract: In order to explore the suitable nitrogen application,the influence of dry matter and nutrient element accumulation and distribution under different N application levels on buckwheat was studied. Field experiment was conducted under different N application rates N₀,N₁,N₂,N₃ and N₄(0,30,60,90,120 kg/ha). The results showed that buckwheat dry matter first increased and then dropped with the increment of nitrogen application rate. When the nitrogen application rate was N₂,the buckwheat dry matter reached the highest. But when the nitrogen application rate was N₃,the seeds dry matter and distribution rate reached the highest. The results also showed that seeds nitrogen,phosphorus and potassium contents first increased and then dropped with the increment of nitrogen application rate.When the nitrogen application rate was N₃,the seeds nitrogen,phosphorus and potassium contents reached the highest. The seeds nitrogen,phosphorus and potassium distribution rate increased with the increment of nitrogen application rate,but it decreased in stems and leaf. The amounts of nutrients which needed for the formation of 100 kg seeds of buckwheat were N 7.09 kg,P₂O₅ 4.15 kg,K₂O 8.74 kg and the rate was 1.00:0.59:1.24.The production efficiency of N,P₂O₅,K₂O first increased and then dropped with the increment of nitrogen application rate. When the nitrogen application rate was N₃,the production efficiency of N,P₂O₅,K₂O reached the highest.With the increase of the amount of nitrogen fertilizer, the dry matter production efficiency of nitrogen and phosphorus first increased, then decreased, and then increased. The dry matter production efficiency of potassium gradually increased, and the production efficiency of N₄, nitrogen, phosphorus and potassium dry matter reached the highest level. Considering the buckwheat dry matter and nutrient element under the experimental conditions,N application rate of 90 kg/ha identified to be the suitable amount.

Key words: N application rates, Buckwheat, Dry matter, Nutrient element, Accumulation and distribution

CLC Number: 

• S51

• S143.1