Although radicle pruning has well been observed in plant–animal interactions, research has not been conducted to determine how radicle pruning by seed-eating animals regulates nutrition mobilization of cotyledonary reserves and absorption of soil nutrients. We used stable nitrogen isotopes to test how acorns of early-germinating oak species (Quercus variabilis, Q. aliena, and Q. mogolica) trade off nutrients in the cotyledons and those in the soil in response to radicle pruning by seed-eating rodents. Radicle pruning by rodents resulted in root branching in the 3 early-germinating oak species. Moreover, radicle pruning increased shoot dry weight and substantially reduced the root-to-shoot ratio of oak species. Corresponding to the decreased dry weight of roots and root-to-shoot ratio, the dry weight of the remnant cotyledons was higher after radicle pruning in the 3 oak species. We provided first evidence that radicle pruning by seed-eating animals improved seedling performance of early-germinating oaks by increasing absorption of nutrients from soil. The results indicate that early-germinating oak seedlings trade off nutrition budget by altering nutrient absorption from soil and reserve mobilization from cotyledons in response to radicle pruning by seed-eating animals. Our study provided new insight into the nutrition allocation mechanism of young seedlings in response to radicle pruning by seed-eating animals, reflecting a mutualistic interaction between early-germinating oak and food-hoarding animals.

中文翻译：

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吃种子的动物修剪胚根有助于橡树幼苗吸收更多的土壤养分

尽管在动植物相互作用中已经很好地观察到胚根修剪，但尚未进行研究以确定食种动物的胚根修剪如何调节子叶储备的营养动员和土壤养分的吸收。我们使用稳定的氮同位素来测试早发橡树（Quercus variabilis、Q. aliena和Q. mogolica ）的橡子如何) 权衡子叶和土壤中的营养物质，以应对食种啮齿动物的胚根修剪。啮齿动物的胚根修剪导致 3 种早发橡树的根分枝。此外，胚根修剪增加了枝条干重并显着降低了橡树种的根茎比。对应于根干重和根冠比的降低，3种橡树胚根修剪后残余子叶的干重较高。我们提供了第一个证据，表明食种动物修剪胚根通过增加土壤中养分的吸收来改善早发橡树的幼苗性能。结果表明，早期发芽的橡树幼苗通过改变土壤中的养分吸收和子叶的储备动员来权衡营养预算，以应对食种动物的胚根修剪。我们的研究为幼苗响应食种动物修剪胚根的营养分配机制提供了新的见解，反映了早发橡树和食物囤积动物之间的共生相互作用。