Effects of Nitrogen Application Rate on Dry Matter Accumulation and Nitrogen Utilization Characteristics of Different Adlay Varieties

Zeng Tao; Pan Hong; Wei Xinyuan; Lu Xiujuan; Shi Ming; Long Shengwei; Li Gang; Li Xiangdong

doi:10.14083/j.issn.1001-4942.2025.05.015

Abstract：Two adlay varieties,JY01(early-maturing)and YZ04(medium-late-maturing),were used as test materials,four nitrogen(N)application rates of 90(N90),180(N180),270(N270),and 360(N360)kg/hm2were set using a randomized block design,and their effects on dry matter accumulation and nitrogen utilization characteristics of each adlay variety were investigated.The results showed that at mature stage,adlay grain yield increased first and then decreased with the increase of N application rate,and the grain yield of YZ04 was significantly higher than that of JY01 at each N level.The aboveground dry matter and nitrogen accumulation in both JY01 and YZ04 showed the trend of increasing first and then decreasing with the increase of N application rate,reaching their peak at 180 kg/hm2of nitrogen.Among which,their maximum dry matter accumulation were 7 100.90 and 19 052.95 kg/hm2,their nitrogen accumulation were 113.44 kg/hm2 and 253.39 kg/hm2,and their grain harvest indices ranged from 38.25～41.09%(JY01)and 25.87～30.74%(YZ04),respectively.For nitrogen grain production efficiency,the value of JY01 was 23.16～25.05 kg/kg which showed no significant difference among N levels.The value of YZ04 was 21.72～26.21 kg/kg showing the trend of increasing first and then decreasing with the increase of nitrogen application rate,and reached the maximum value at N270 level which showed no significant difference with other treatments.The ni-trogen harvest indices of JY01 and YZ04 were 45.85～50.93%and 46.57～55.26%,respectively.Nitrogen re-quirement per 100 kg of grains increased first and then decreased with the increase of nitrogen application rate,reaching their peak at the nitrogen application rate of 270 kg/hm2,which was 4.32 kg and 4.60 kg,re-spectively.It was known according to the linear regression equation fitting the nitrogen application rate with the grain yield,the optimal N application rates for JY01 and YZ04 was 259.21 kg/hm2 and 222.67 kg/hm2.