不同氮效率小麦品种根系特征及根际土壤酶活性的分析

为探明不同氮效率小麦（Triticum aestivum L.）品种根系特征及其对根际土壤酶活性的响应，以30年的长期定位试验为平台，于2018—2020年采用大田试验的方法，在不同氮效率品种筛选的基础上，以氮高效小麦品种郑麦113、偃高21和氮低效小麦品种丰德存5号、周麦27为试验材料，在不施氮肥（N0）和正常施氮肥（N1）条件下研究其根系特征、氮素吸收利用及根际土壤酶活性的差异。结果表明，各品种小麦的根系活力均在孕穗期达到最大值，N0、N1水平下氮高效小麦品种根系活力的平均值分别比氮低效小麦品种增加了16.13%～24.22%、10.22%～62.49%。N1水平下小麦根长、根表面积和根体积明显高于N0水平。郑麦113、偃高21、周麦27的氮吸收效率显著高于丰德存5号，而周麦27的氮利用效率较低。两种氮水平处理下，郑麦113和偃高21的根际土壤β-葡萄糖苷酶（BG）、亮氨酸氨基肽酶（LAP）和多酚氧化酶（POX）活性整体显著高于丰德存5号和周麦27(P<0.05)，且根际土壤酶活性与根系形态指标均呈正相关关系。这说明郑麦113和偃高21较高的根系活力、根长、根表面积和根体积促...

Analysis of Root Characteristics and Rhizosphere Soil Enzyme Activities of Wheat Varieties With Different Nitrogen Efficiencies

To explore the characteristics of the root systems of wheat （Triticum aestivum L.） varieties with different nitrogen （N） efficiencies and their responses to rhizosphere soil enzyme activities， a field experiment was conducted based on 30-year long-term trial site during 2018—2020， in which the wheat varieties included in N efficient varieties of Zhengmai 113 （ZM 113） and Yangao 21 （YG 21）， and N inefficiency varieties of Fengdecun 5 （FDC 5） and Zhengmai 27 （ZM 27）. The root characteristics， N absorption and utilization， and differences in root soil enzyme activities were studied under conditions of no N fertilizer （N0） and conventional N fertilizer （N1）. The results indicated root vigor reached the maximum at the booting stage for all varieties. At the N0 level， the average root vigor of ZM 113 and YG 21 was 16.13%~24.22% higher than that of ZM 27 and FDC 5. Meanwhile， it was 10.22%~62.49% at the N1 level. The root length， root surface area， and root volume were significantly higher under N1 treatment compared with those under N0 treatment. The N uptake efficiency of ZM 113， YG 21， and ZM 27 was significantly higher than that of FDC 5， while N use efficiency of ZM 27 was relatively low. Under the fertilization treatments， rhizosphere soil β-glucosidase （BG）， eucine amiopeptidase （LAP）， and polyphenol oxidase （POX） activities of ZM 113 and YG 21 were significantly higher than FDC 5 and ZM 27 （P<0.05）. Besides， there was a positive correlation between rhizosphere soil enzyme activity and root morphological indexes. This indicated that the higher root activity， root length， root surface area， and root volume of ZM 113 and YG 21 promoted the uptake of nitrogen， which was the fundament for high nitrogen efficiency， and higher rhizosphere soil enzyme activity promoted the efficient use of nitrogen. This study provided a theoretical basis for the breeding and cultivation of nitrogen-efficient wheat varieties.