黄河三角洲贝壳堤滩脊地带干旱生境下，酸枣因受日本菟丝子严重寄生，导致植被退化严重，显著降低泥质海岸带防护林生态功能。AMF能提高植物对寄生的耐性，但关于干旱和AMF对植物寄生关系的交互影响及其机制尚不清晰。针对贝壳堤植物共生关系和寄生关系的作用过程及交互效应这一科学问题，拟阐明AMF和干旱对酸枣响应日本菟丝子寄生的交互影响及其生理学机制。以贝壳堤优势灌木酸枣为研究对象，基于野外调查和模拟控制相结合的实验方法，采用稳定同位素示踪技术，开展土壤水分、AMF和日本菟丝子寄生对酸枣生长特征及作用机制研究。探讨贝壳堤土壤水分对日本菟丝子和酸枣寄生关系的生理调控规律，解析AMF如何影响酸枣生长进而级联调控寄生关系的作用过程和生理学基础，明确土壤水分对寄生关系的影响是否依赖AMF，阐明土壤水分对“共生微生物-植物-寄生植物”的多重互作过程及其生理调控机制，以期为贝壳堤退化生态系统的植被恢复提供理论依据。

The vegetation has seriously degraded at Shell Island in the Yellow River Delta, because a mount of dominant plant Ziziphus jujube has been parasitized by Cuscuta japonica and the drought may influence this process. Although previous studies have demonstrated that AMF can improve the tolerance of host plants to parasitic plants, it remains unclear for the effect of drought and AMF on the interactions between host plants and parasitic plants and its underlying physiological mechanisms. Using Z. jujube as the host plant, a field research survey and three greenhouse experiments will be investigated. In the field survey, we will study the interaction between parasitism by C. japonica and the ratio of colonization by AMF. Using 13C and 15N isotope labeling technique, two greenhouse experiments will be conducted to reveal: 1) the mechanisms of drought and parasitism by C. japonica on the growth of the Z. jujube; 2) the mechanisms of AMF and parasitism by C. japonica on the growth of the Z. jujube; Finally, a three-way experiment including two soil water availability treatments (drought vs. control), two AMF treatments (present vs. absent) and two parasitism treatments (present vs. absent) will be conducted, to estimate the interactive effects of soil water availability, AMF and parasitism by C. japonica on the growth of the Z. jujube. The results will provide new insights into the ecological interactions between mutualism and parasitism via the same host plants and the scientific baseline for more effective management of parasitic plants, which is crucial for successful conservation of biodiversity and ecosystem functions in the valuable Shell Island of Yellow River Delta.