变性淀粉包裹型尿素对氮素释放特性及生物学效应的影响

The Impact of Modified Starch-coating-urea on Nitrogen Release Characteristics and Biological Effect

采用水浸法、土柱淋溶法和盆栽方法研究了变性淀粉包裹型尿素氮素释放特性及生物学效应。结果表明:水浸和土柱淋溶试验中,FCU与RCU-J、RCU-C氮素释放差别很大,而RCU-J和RCU-C氮素释放具有相似性,并且与在水中相比,FCU在土壤中氮素释放速率明显降低,氮素释放曲线变化较大。苗期的玉米盆栽试验中,过量、适宜水分条件下,与Urea相比,FCU促进了植株干物重和吸氮量显著增加。干旱胁迫条件下,与RCU相比,FCU植株干物重和吸氮量降低幅度较小。通过用土柱淋溶和盆栽方法对FCU的测定结果进行相关分析可知,两种方法之间具有极显著的相关性,对FCU的评价可以采用土柱淋溶法,而采用两种方法相结合更能反映包膜肥的实际缓释特性。

Water dissolution rate method, soil column leaching method and pot experiment were used to study the nitrogen release and biological effect of Urea which coated by modified starch. The results showed that：during the water dissolution rate method and soil column leaching method,the nitrogen release of FCU had many differences with the RCU-J and RCU-C ,but the nitrogen release of RCU-J and RCU-C was similar,and compared with in water,the nitrogen release rate of FCU in soil reduced significantly,and the releasing curve changed greatly. During the corn pot experiment at the seedling stage,under the condition of excessive and normal water,FCU promoted the dry matter weight and nitrogen uptake compared with Urea. Under the condition of drought stress, the reduction of the two indexes of FCU were relatively moderate compared with RCU. According to the correlation analysis of the results measured by soil column leaching method and pot experiment of FCU,the two methods had significant correla- tion,the soil column leaching method can be used to evaluate FCU, and it was better to reflect the actual slow-release characteristics by using the two methods together.