S型控释氮肥运筹对水稻产量形成及氮素利用特征的影响OACSTPCD

CRFN has the characteristics of less application times and high fertilizer utilization rate,and S-type thermosetting resin-coated controlled release nitrogen fertilizer(S-type CRFN)is less affected by soil pH and has good fertilizer stability.In this study,S-type CRFN was used as the test material,and 4 pot experiments were set up to compare the response of 6 rice varieties,4 nitrogen application rates,5 nitrogen application periods,and 7 nitrogen application ratios,respectively,to study the effects of S-type CRFN on rice yield formation,nitrogen uptake and uti-lization.The results showed as follows:1)In the variety comparison test,S-type CRFN increased the yield of 6 rice varieties by 2.95%-18.57%,with an average increase of 12.60%;the increase in yield was due to the increase in panicle number or spikelets per panicle;S-type CRFN significantly increased the nitrogen accumulation and nitrogen use efficiency of rice at the mature stage,but it decreased the nitrogen grain production efficiency.2)In the CRFN operation test,with the increase of the application amount and proportion of S-type CRFN,the yield of Wuyunjing 24 showed a trend of first increase and then decrease,the yield increased the most in the treatment of 3 g pure nitrogen per pot and 80%controlled release nitrogen,respectively,and the yield increase effect was more significant when S-type CRFN was used as base fertilizer;the highest nitrogen absorption of Wuyunjing 24 at the mature stage was in the treatment of 4.5 g pure nitrogen per pot and controlled release nitrogen treatment(80%),and S-type CRFN in-crease effect was more significant than conventional fertilization treatment in base fertilizer.N grain production effi-ciency and N use efficiency showed a decreasing trend.N grain production efficiency was the highest when con-trolled release N(0%)and controlled release fertilizer were used as protection fertilizer,and N use efficiency was the highest when controlled release N(80%)and controlled release fertilizer were used as base fertilizer,respectively.3)In the experiment of the effect of CRFN on the root traits,S-type CRFN treatment increased the total length of advents root,root dry weight and absorption area per plant at day 30 after planting,and increased the total length of advents root,root dry weight and root vigor per plant at the head stage of Wuyunjing 24 rice;the increase of the number of the adventitious roots,total length of adventitious roots,root dry weight and root activity was the root basis for the synergistic increase of yield,nitrogen accumulation and nitrogen use efficiency.In conclusion,S-type CRFN can sig-nificantly improve the yield and nitrogen use efficiency of rice,and it has the best effect as the base fertilizer.Yield,nitrogen accumulation at the maturity and nitrogen utilization rate increased synergically when the ratio of controlled release N was about 80%with the treatment of 3 g pure N per pot,which was closely related to root character opti-mization of the heading stage at day 30 after planting.