Zhou Hanchang, Huang Siyuan, Zhang Ziying, Li Ting, Li Yi, Zhuang Guoqiang, Liu Guohua, Fu Bojie, Kuang Xiaobao
The Bamboo Institute, Jiangxi Academy of Forestry, Nanchang, China.
The Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, China.
Front Plant Sci. 2024 Nov 27;15:1492137. doi: 10.3389/fpls.2024.1492137. eCollection 2024.
The imbalanced fertilization and the consequential deterioration on the rhizosphere microbial community (RMC) were two potential reasons for the quick yielding degradation of (Lei-bamboo), a high-value shoot-oriented bamboo. However, most research only focused on nitrogen, phosphorus, and potassium; the studies on the dynamics of other nutrients, such as calcium and magnesium; and their driving mechanisms, lags far behind. Thus, Lei-bamboo fields of different mulching and recovery ages were selected to investigate the dynamics of calcium and magnesium in both soil and bamboo tissue, and to explore their relationship to RMC composition and network patterns. The results showed that mulching increased the content of soil acidification, total organic carbon, alkali-hydrolysable nitrogen, available phosphorus, and available potassium but reduced soil exchangeable magnesium and calcium in soil as well as the magnesium and calcium content in rhizome, stem, and leaf of Lei-bamboo, which indicated an increased relative limitation on magnesium and calcium. Mulching also enhanced the α-diversity and reshaped the composition of RMC, which had a close link to Mg rather than nitrogen, phosphorus, and potassium. As the mulching years increased, the RMC network became bigger and more complex, and the magnesium and calcium gradually appeared in the network center, which further support the magnesium and calcium deficiency to RMC. Nearly all the variation mentioned above could be revered after the removing of mulching. Structural equation modeling showed two main pathways that mulching leads to magnesium and calcium deficiency in Lei-bamboo, one is directly by lowering soil magnesium and calcium content, the other one is indirectly by improving RMC network interactions, a sign of weakened mutualism between RMC and plant roots that hampering the uptake of nutrients. This research highlights the quick magnesium and calcium deficiency caused by mulching in Lei-bamboo forest and the contribution of RMC in amplify the effects of soil magnesium and calcium deficiency, which offers valuable information on balancing fertilization pattern for future sustainable Lei-bamboo cultivation.
不均衡施肥以及随之而来的根际微生物群落（RMC）退化是高价值笋用竹雷竹产量快速下降的两个潜在原因。然而，大多数研究仅关注氮、磷、钾；对钙和镁等其他养分动态及其驱动机制的研究远远滞后。因此，选取不同覆盖和恢复年限的雷竹林，研究土壤和竹组织中钙和镁的动态变化，并探讨它们与RMC组成和网络模式的关系。结果表明，覆盖增加了土壤酸化、总有机碳、碱解氮、有效磷和速效钾的含量，但降低了土壤中交换性镁和钙以及雷竹根状茎、茎和叶中的镁和钙含量，这表明对镁和钙的相对限制增加。覆盖还增强了RMC的α多样性并重塑了其组成，这与镁而非氮、磷、钾密切相关。随着覆盖年限的增加，RMC网络变得更大、更复杂，镁和钙逐渐出现在网络中心，这进一步证明了RMC存在镁和钙缺乏的情况。去除覆盖后，上述几乎所有变化都可以逆转。结构方程模型表明，覆盖导致雷竹镁和钙缺乏有两条主要途径，一条是直接降低土壤镁和钙含量，另一条是间接通过改善RMC网络相互作用，这表明RMC与植物根系之间的互利共生关系减弱，从而阻碍了养分吸收。本研究突出了雷竹林覆盖导致的快速镁和钙缺乏以及RMC在放大土壤镁和钙缺乏效应方面的作用，为未来雷竹可持续种植的平衡施肥模式提供了有价值的信息。
