Song Wenchen, Wang Jing, Hou Lei
Key Laboratory of Ecology and Environment in Minority Areas, Minzu University of China, National Ethnic Affairs Commission, Beijing, China.
College of Life and Environmental Sciences, Minzu University of China, Beijing, China.
Front Microbiol. 2022 Aug 24;13:976154. doi: 10.3389/fmicb.2022.976154. eCollection 2022.
Stover mulching as a conservation and sustainable agricultural practice is beneficial for maintaining soil nitrogen (N) requirements and plant health. The microbial functional guilds of the root and rhizosphere are important factors in the soil nitrogen cycle. However, it is unclear how the frequency and amount of stover mulching influence microbial functional guilds in the root and rhizosphere. Therefore, we investigated the responses of the microbial functional guilds in the endosphere and rhizosphere to maize stover mulching amounts (0, 1/3, 2/3, and total stover mulching every year) and frequencies (once every 3 years and twice every 3 years) under 10-year no-till management. The bacterial functional guilds of nitrogen fixation, nitrification, and anaerobic nitrate oxidation displayed the significantly correlation with C/N, total nitrogen, NO , and NH . The fungal functional guilds of plant pathogens and saprotrophs showed significantly correlations with C/N, total nitrogen, and NO . Moreover, we found that bacterial guilds play a pivotal role in maintaining N requirements at the jointing stage, whereas root endophytic fungal guilds play a more important role than bacterial guilds in regulating plant health at the mature stage. The frequency and amount of stover mulching had significant effects on the microbial functional guilds in the root and rhizosphere. Our data suggest that stover mulch application twice every 3 years is the optimal mulching frequency because it yielded the lowest abundance of nitrifying and anaerobic nitrate-oxidising bacteria and the highest abundance of nitrogen-fixing bacteria at the jointing stage, as well as the lowest abundance of fungal plant pathogens in roots at the mature stage.
作为一种保护性和可持续农业实践的秸秆覆盖，有利于维持土壤氮素需求和植物健康。根系和根际的微生物功能类群是土壤氮循环的重要因素。然而，尚不清楚秸秆覆盖的频率和数量如何影响根系和根际的微生物功能类群。因此，我们研究了在10年免耕管理下，内生菌和根际中微生物功能类群对玉米秸秆覆盖量（0、1/3、2/3和每年全量秸秆覆盖）和频率（每3年一次和每3年两次）的响应。固氮、硝化和厌氧硝酸盐氧化的细菌功能类群与碳氮比、总氮、硝酸根和铵根显著相关。植物病原体和腐生菌的真菌功能类群与碳氮比、总氮和硝酸根显著相关。此外，我们发现细菌类群在拔节期维持氮素需求方面起关键作用，而根内生真菌类群在成熟期调节植物健康方面比细菌类群发挥更重要的作用。秸秆覆盖的频率和数量对根系和根际的微生物功能类群有显著影响。我们的数据表明，每3年进行两次秸秆覆盖是最佳覆盖频率，因为它在拔节期产生的硝化和厌氧硝酸盐氧化细菌丰度最低，固氮细菌丰度最高，在成熟期根系中真菌植物病原体的丰度最低。
