Institute of Soil & Fertilizer and Resources & Environment, National Engineering and Technology Research Center for Red Soil Improvement, Jiangxi Academy of Agricultural Sciences, Nanchang, 330200, P.R. China.
College of Resource and Environment, Microelements Research Center, Huazhong Agricultural University, Wuhan, 430070, P.R. China.
Sci Rep. 2017 Jun 15;7(1):3577. doi: 10.1038/s41598-017-03919-y.
Chinese milk vetch (CMV) is vital for agriculture and environment in China. A pot experiment combined with N labeling (including three treatments: control, no fertilizer N and CMV; N-labeled urea alone, NU; substituting partial NU with CMV, NU-M) was conducted to evaluate the impact of CMV on plant growth, development and NU recovery in rice-based rotation system. The NU-M mitigated oxidative damage by increasing antioxidant enzymes activities and chlorophyll content while decreased malondialdehyde content in rice root and shoot, increased the biomass, total N and N uptake of plant shoots by 8%, 12% and 39% respectively, thus inducing a noticeable increase of annual N recovery by 77% versus NU alone. Remarkable increases in soil NH and populations of bacteria, actinomycetes and azotobacter were obtained in legume-rice rotation system while an adverse result was observed in soil NO content versus fallow-rice. CMV as green manure significantly increased the fungal population which was decreased with cultivating CMV as cover crop. Therefore, including legume cover crop in rice-based rotation system improves plant growth and development, annual N conservation and recovery probably by altering soil nitrogen forms plus ameliorating soil microbial communities and antioxidant system which alleviates oxidative damages in plants.
紫云英在中国的农业和环境中至关重要。采用盆栽试验与氮标记（包括三种处理：对照、无肥氮和紫云英；单独使用氮标记尿素、NU；用紫云英替代部分 NU、NU-M）相结合的方法，评估了紫云英对水稻轮作系统中植物生长、发育和 NU 回收的影响。NU-M 通过增加抗氧化酶活性和叶绿素含量来减轻氧化损伤，同时降低水稻根和茎中的丙二醛含量，使植物地上部分的生物量、总氮和氮吸收量分别增加 8%、12%和 39%，从而使 NU 单独处理时的年氮回收率显著提高 77%。在豆稻轮作系统中，土壤 NH 和细菌、放线菌和固氮菌的数量显著增加，而与休耕稻相比，土壤 NO 含量则呈下降趋势。紫云英作为绿肥显著增加了真菌的数量，而作为覆盖作物种植则降低了真菌的数量。因此，在水稻轮作系统中包括豆科覆盖作物可以促进植物生长和发育，提高年氮素保存和回收利用率，可能是通过改变土壤氮素形态，改善土壤微生物群落和抗氧化系统，从而减轻植物的氧化损伤。
