Chungbuk National University, Cheongju, Chungbuk, 28644, South Korea.
Soil Research Institute, Prumbio Co. Ltd, South Korea.
Environ Pollut. 2021 Dec 15;291:118132. doi: 10.1016/j.envpol.2021.118132. Epub 2021 Sep 8.
Urea is one of the most commonly used nitrogen fertilizers in agricultural soil and is easily decomposed by soil urease resulting in ammonium release. The produced ammonium can be volatilized or converted to nitrate, which is susceptible to leaching, leading to groundwater contamination unless used by plants. Hence, it is important to control the release of nitrogen from the urea. Pyroligneous acid inhibited the urease activity and decreased ammonium release up to 80% compared to the control. Amidase including asparaginase and glutaminase is an enzyme that catalyzes hydrolysis of amide group, similar to urease. Therefore, the effect of pyroligneous acid on the inhibition of soil amidase was also tested and the results showed that pyroligneous acid competitively inhibited asparaginase while glutaminase was not inhibited. However, inhibitory effect of pyroligneous acid on asparaginase was negligible compared to the urease. The application of pyroligneous acid with a smaller amount of urea for controlled nitrogen release during Chinese cabbage growth showed that dry biomass and nutrient contents of Chinese cabbage were similar to the case of the conventional urea application. The nitrogen utilization efficiency (NUE) was highest for 33% less amount of urea supply with pyroligneous acid (2.21) compared to conventional treatment (1.81). Consequently, the use of pyroligneous acid with urea enhances nitrogen use efficiency while also protecting environments from non-point source contamination.
尿素是农业土壤中最常用的氮肥之一，很容易被土壤中的脲酶分解，导致铵释放。产生的铵可以挥发或转化为硝酸盐，如果植物不利用，就容易随水流失，导致地下水污染。因此，控制尿素中的氮释放非常重要。木醋液抑制了脲酶的活性，与对照相比，铵的释放量减少了 80%。酰胺酶包括天冬酰胺酶和谷氨酰胺酶，是一种催化酰胺基团水解的酶，与脲酶相似。因此，还测试了木醋液对土壤酰胺酶抑制作用的影响，结果表明，木醋液竞争性地抑制天冬酰胺酶，而谷氨酰胺酶不受抑制。然而，与脲酶相比，木醋液对天冬酰胺酶的抑制作用可以忽略不计。在小白菜生长过程中，与常规尿素应用相比，应用木醋液与少量尿素控制氮释放，表现出小白菜的干生物量和养分含量相似。氮利用率（NUE）最高，木醋液（2.21）比常规处理（1.81）少用 33%的尿素。因此，木醋液与尿素一起使用可以提高氮素利用效率，同时保护环境免受非点源污染。
