Effect of Application Level of Nitrogen on Dry Matter Accumulation, Yield and Nitrogen Uptake and Utilization of Different Genotypes of High-quality Wheat

ZHANG Yunhong; SUN Kegang; DU Jun; DU Baochi; HE Ailing; DING Hua; XU Weigang; CHENG Xiaolong

doi:10.15933/j.cnki.1004-3268.2017.04.003

Abstract：A field experiment was carried out to study the effect of application levels (0,120,180,240 kg/ha) of nitrogen on dry matter accumulation,yield and nitrogen uptake and utilization of three genotypes of high-quality wheat (Zhengmai 0943,Zhengmai 0856 and Zhengmai 7698),so as to reveal the characteristics of nitrogen utilization of high-quality wheat and provide scientific basis for realization of great yield potential and appropriate fertilization management.The results showed that nitrogen application promoted the growth of three genotypes of high-quality wheat to different extent.At nitrogen level of 0-240 kg/ha,SPAD value of functional leaves,dry matter accumulation and yield factors overall increased with the increase of nitrogen level (except Zhengmai 0856).On the comparison among different genotypes of wheat varieties,yield of all nitrogen treatments of Zhengmai 7698 were higher than those of two other wheat varieties,mainly due to the increase in grain number per panicle and thousand seed weight,the 240 kg/ha nitrogen treatment of Zhengmai 7698 had the maximum values in yield(11 591.70 kg/ha),dry matter transfer rate(29.45％) and its contribution to grain(91.66％);the extents of variation in nitrogen use efficiency,nitrogen absorption efficiency and nitrogen agronomic efficiency of Zhengmai 7698were relatively large with the increase of nitrogen level.The yield of Zhengmai 0856 was the lowest under the no nitrogen treatment,and the decline of yield was the biggest compared to its highest yield (10 200.00kg/ha) of 180 kg/ha nitrogen treatment,with a drop of 18.63％;its nitrogen agronomic efficiency was significantly higher than those of two other wheat varieties,which indicated that Zhengmai 0856 was more sensitive to nitrogen.Under the condition of no nitrogen,Zhengmai 0943 had the minimum values in dry matter transfer rate and its contribution rate to grain,and the decline of yield was the smallest compared to its highest yield (9 933.45 kg/ha) of 240 kg/ha nitrogen treatment,with the drop of 8.89％;its nitrogen harvest index was higher than those of two other wheat varieties;nitrogen use efficiency of Zhengmai 0943 under the treatments of no nitrogen and high nitrogen were relatively large,which indicated that Zhengmai 0943 showed the characteristics of nitrogen high-efficiency use,and dry matter was mainly accumulated in early growth period.In conclusion,the yield of Zhengmai 7698 was higher than those of two other wheat varieties under the condition of no nitrogen,and the optimum nitrogen application level was 240 kg/ha;the yield of Zhengmai 0856 was sensitive to nitrogen deficiency,and the optimum nitrogen application level was 180 kg/ha;the yield of Zhengmai 0943 was not sensitive to nitrogen deficiency,and the optimum nitrogen application level was 240 kg/ha.