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在温室采用脲酶活性强的稻田土壤进行水稻盆栽试验,比较了脲酶抑制剂NBPT不同浓度(按尿素施用量的0.5％、1％、2％、5％)和不同施用方法(①NBPT与尿素同时施UN;②NBPT和PPD以相同深度混合后与尿素一道施UNP;③NBFT在尿素施用前三天施用N+U;④NBPT与尿素施后通氧一小时UNO;⑤NBPT经双氧水预氧化后与尿素一道施UNH)对尿素水解的抑制效果,定期测定淹灌水的氨态氮浓度和剩余尿素浓度,并测定植株总吸氮量,计算氮素利用率。 试验结果表明:施用脲酶抑制剂NBPT的处理均不同程度地表现出抑制尿素水解的效果,随着抑制剂施用浓度的增加,抑制效果明显增强。在低抑制剂浓度条件下,尿素全部水解所需时间为7～8天,高抑制剂浓度条件下为9～10天;而不施抑制剂的对照处理,尿素施后4天可全部水解。NBPT不同施用方法对比,N+U、UNH、UNP和UNO在开始几天均不同程度地较UN有较强的抑制效果,尤以N+U和UNH更为明显,但四、五天后各处理差异不大。淹灌水氨态氮浓度的测定结果与上述结果相吻合。施用NBPT后,淹灌水的氨态氮浓度峰值明显降低,出现时间推迟,有效氮的供应期限延长4～6天,减少了氮的挥发损失。在水稻植株上表现为总吸氮量增加,氮索利用率提高,埴株干重也有一定增长。在盆栽条件下,NBPT与尿素—同施能表现出较好的效果,不?
Pot experiments were conducted in paddy soils with strong urease activity in the greenhouse. Different concentrations of urease inhibitor NBPT (0.5%, 1%, 2%, 5%) and different application methods (NBPT and urea simultaneously applied) UN; ②NBPT and PPD mixed with urea at the same depth after UNP; ③NBFT three days before the urea application of N + U; ④NBPT and urea after oxygen for one hour UNO; ⑤ NBPT by hydrogen peroxide pre-oxidation with urea UNH ) On the inhibition of urea hydrolysis. The concentrations of ammonia nitrogen and residual urea in the flooded irrigation water were determined regularly. The total nitrogen uptake of the plants was determined and the nitrogen utilization efficiency was calculated. The results showed that the application of the NBPT urease inhibitor inhibited the hydrolysis of urea to some extent. With the increase of inhibitor concentration, the inhibitory effect was obviously enhanced. Under the condition of low inhibitor concentration, the time required for the complete hydrolysis of urea was 7 to 8 days and that of high inhibitor concentration was 9 to 10 days. Without the inhibitor control, all the hydrolysis was completed 4 days after urea application. Compared with NBPT, N + U, UNH, UNP and UNO were more potent than UN in the first few days, especially N + U and UNH, but after four or five days Little difference. The results of determination of ammonia nitrogen concentration in submerged irrigation water are consistent with the above results. After application of NBPT, the peak value of ammonia nitrogen concentration in submerged irrigation water obviously decreased, the emergence time was delayed, the supply of available nitrogen was extended for 4-6 days, and the loss of nitrogen volatilization was reduced. In rice plants showed an increase in total nitrogen uptake, Nitrogen utilization rate increased, dry weight also had a certain growth. Under potting conditions, NBPT and urea - co-administered to show good results, not?