Nie Jiangwen, Xie Qingyun, Zhou Yong, He Feng, Yousaf Muhammad, Zhu Bo, Liu Zhangyong
Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland/Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, College of Agriculture, Yangtze University, Jingzhou, China.
College of Life Science and Technology, Hubei Engineering University, Xiaogan, China.
Front Plant Sci. 2025 Jun 3;16:1603434. doi: 10.3389/fpls.2025.1603434. eCollection 2025.
Chinese milk vetch (vetch) is a promising winter cover crop that can reduce dependence on fertilizers and enhance crop productivity in southern China. However, its impact on soil microbial communities, soil quality, and rice yield, particularly when comparing the incorporation of green manure residue to mowing, remains insufficiently explored.
To address this gap, an 12-year field experiment was conducted in the Dongting Lake Plain, comparing three vetch management strategies under double-rice cropping system: winter fallow (CK), vetch rotation with residue incorporation (CMI), and vetch rotation with residue mowing (CMR). The soil quality index (SQI) was calculated based on abiotic [e.g., soil organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO-N)] and biotic [e.g., bacterial abundance, abundance-based coverage (ACE), Chao 1] factors.
Results indicated that both the vetch management strategies significantly improved rice yield. Compared to CK, CMI and CMR enhanced early, late, and annual rice yields by 6.22%-10.77%, 7.50%-13.49%, and 7.03%-12.40%, respectively. Additionally, CMI improved soil redox potential, alkali-hydrolyzale nitrogen, ammonium nitrogen, and NO-N, while CMR enhanced soil SOC, TN, NO-N levels. Both CMI and CMR resulted in increases in the bacterial ACE index by 2.43%-2.53% and the Chao1 index by 0.92%-2.88% (P < 0.05). Furthermore, CMI reduced the Shannon index by 1.17% but increased the Simpson index by 19.35%, while CMR increased the Shannon index by 1.73% and elevated the Simpson index by 19.35% (P < 0.05). Principal component analysis indicated distinct bacterial community structures between CK and CMR. The dominant bacterial phyla included Proteobacteria, Chloroflexi, Nitrospirae, Acidobacteria, Bacteroidetes, and Actinobacteria. Notably, CMR exhibited lower relative abundances of Proteobacteria, Nitrospirae, and Acidobacteria compared to CMI. Compared to CK, CMI increased SQI by 6.92%, while CMR showed more modest improvements in soil quality. Moreover, a strong positive correlation between rice yield and SQI further confirmed the beneficial effect of vetch rotation on soil fertility. These findings underscore the potential of vetch rotation, particularly through vetch incorporation, to enhance soil quality and rice productivity, thereby offering valuable insights for sustainable agricultural practices.
紫云英是一种很有前景的冬季覆盖作物，它可以减少对化肥的依赖，并提高中国南方地区的作物产量。然而，它对土壤微生物群落、土壤质量和水稻产量的影响，特别是在比较绿肥残茬翻埋和刈割的情况下，仍未得到充分研究。
为了填补这一空白，在洞庭湖平原进行了一项为期12年的田间试验，比较了双季稻种植系统下的三种紫云英管理策略：冬季休耕（CK）、紫云英翻压轮作（CMI）和紫云英刈割轮作（CMR）。土壤质量指数（SQI）是根据非生物因素[如土壤有机碳（SOC）、全氮（TN）、硝态氮（NO₃-N）]和生物因素[如细菌丰度、基于丰度的覆盖率（ACE）、Chao1指数]计算得出的。
结果表明，两种紫云英管理策略均显著提高了水稻产量。与CK相比，CMI和CMR分别使早稻、晚稻和年水稻产量提高了6.22%-10.77%、7.50%-13.49%和7.03%-12.40%。此外，CMI提高了土壤氧化还原电位、碱解氮、铵态氮和NO₃-N含量，而CMR提高了土壤SOC、TN、NO₃-N含量。CMI和CMR均使细菌ACE指数提高了2.43%-2.53%，Chao1指数提高了0.92%-2.88%（P<0.05）。此外，CMI使香农指数降低了1.17%，但辛普森指数提高了19.35%，而CMR使香农指数提高了1.73%，辛普森指数提高了19.35%（P<0.05）。主成分分析表明，CK和CMR之间的细菌群落结构明显不同。优势细菌门包括变形菌门、绿弯菌门、硝化螺旋菌门、酸杆菌门、拟杆菌门和放线菌门。值得注意的是，与CMI相比，CMR中变形菌门、硝化螺旋菌门和酸杆菌门的相对丰度较低。与CK相比，CMI使SQI提高了6.92%，而CMR对土壤质量的改善较为有限。此外，水稻产量与SQI之间的强正相关进一步证实了紫云英轮作对土壤肥力的有益影响。这些发现强调了紫云英轮作，特别是通过紫云英翻压，在提高土壤质量和水稻生产力方面的潜力，从而为可持续农业实践提供了有价值的见解。
