Fallow waterlogged paddy field (FWPF) is a subtropical type of winter-spring fallow rice fields. Arthropod predation is crucial for their survival during the long-duration FWPF seasons. No research has been conducted in the trophic link of arthropod predators and their prey in FWPFs. Here, we used a quantitative real-time PCR approach, both in lab and field, to detect the trophic link. DNA-based identification confirmed the results of a morphological classification in two dominant species of springtail, Homidia socia Denis and H. tiantaiensis Chen and Lin (Collembola: Entomobryidae). The fastest degradation in H. socia DNA copy numbers in spider Pirata subpiraticus (Bösenberg and Strand) (Araneida: Lycosidae) guts occurred within 8 h under lab conditions. Quantitative comparisons of preying on H. socia by H. socia DNA copy numbers indicated that Oedothorax insecticeps (Bösenberg and Strand), Erigonidium graminicolum (Sundevall) (Araneida: Linyphiidae) and P. subpiraticus were more active springtail predators than others under field conditions. There were significant differences in the DNA copy numbers of springtails in gut of P. subpiraticus among different overwintering periods that was significantly positive related to the springtail densities. This study highlights springtail importance at species level as the prey of spiders in FWPFs and illustrates the utility of our approach to quantify their trophic linkages among different spider species or postharvest seasons.

淡水稻田（FWPF）是亚热带类型的冬春休耕稻田。节肢动物的捕食对其长期FWPF季节的生存至关重要。在节肢动物的节肢动物食肉动物及其猎物的营养联系上，尚未进行任何研究。在这里，我们在实验室和现场都使用了定量实时PCR方法来检测营养连接。基于DNA的鉴定证实了两个主要的跳尾物种形态学分类的结果，即Homidia socia Denis和H. tiantaiensis Chen和Lin（Collembola：Entomobryidae）。H降解最快。蜘蛛Pirata subpiraticus中的社会DNA拷贝数（Bösenbergand Strand）（Araneida：Lycosidae）的肠道在实验室条件下在8小时内发生。H捕食的定量比较。socia通过^ h。socia DNA拷贝数表明Oedothorax insecticeps（Bösenberg和绞线），草间小黑蛛（Sundevall）（Araneida：皿蛛）和P。水狼蛛更为活跃跳虫的天敌比别人野外条件下。P肠的跳尾DNA拷贝数差异显着 。p下在不同的越冬期中，与尾the密度显着正相关。这项研究突显了跳尾蛙在FWPF中作为蜘蛛的猎物在物种层面上的重要性，并说明了我们的方法在量化不同蜘蛛物种或收获后季节之间的营养联系方面的实用性。