Inside bamboo nodes: how plants control mineral flow

Plants rely on efficient internal transport systems to distribute essential mineral nutrients, yet how this distribution is spatially organized within complex plant structures remains poorly understood. This study reveals that nodes—distinct junctions connecting different plant organs—play a central role in coordinating mineral element deposition and transport in bamboo. By systematically examining the internal vascular architecture of different node types and mapping the spatial distribution of key mineral elements, the research demonstrates that nodes function not merely as structural connectors but as active hubs that regulate nutrient allocation. The findings provide new insight into how plants manage mineral distribution under varying growth conditions and highlight nodes as critical control points within plant vascular networks.

In vascular plants, mineral nutrients are traditionally thought to be distributed primarily through transpiration-driven transport along vascular tissues. However, this model cannot fully explain how rapidly growing or underground tissues with low transpiration demands receive sufficient nutrients. In grasses and cereals, nodes have been suggested to play specialized roles in redirecting mineral flows, but most studies have focused on a single node type or a limited set of elements. Bamboo presents a unique system because it possesses multiple distinct node types—culm, shoot, and rhizome nodes—each associated with different growth environments. Based on these challenges, there is a clear need to conduct in-depth research into how node structure governs mineral distribution in plants.

Researchers from Zhejiang Agriculture & Forestry University reported (DOI: 10.1093/hr/uhaf113) on 24 April 2025 in Horticulture Research, that bamboo nodes function as central hubs for mineral element distribution. By integrating detailed anatomical analysis with mineral staining techniques, the team investigated how vascular bundle structure influences the spatial deposition of iron, zinc, calcium, and potassium across different node types in Moso bamboo (Phyllostachys edulis). Their findings reveal coordinated relationships between vascular architecture and nutrient allocation, reshaping current understanding of how plants regulate mineral transport beyond simple transpiration-driven models.

The study systematically compared the vascular bundle organization of culm, shoot, and rhizome nodes using microscopic sectioning and three-dimensional anatomical analysis. Despite their different growth environments, all node types exhibited complex networks composed of enlarged, diffuse, and transit vascular bundles, interconnected by parenchyma tissues. However, each node type showed distinct structural adaptations. Culm nodes possessed well-developed xylem and phloem regions, while shoot and rhizome nodes displayed reduced phloem development, reflecting their lower demand for photoassimilate transport.

To link structure with function, the researchers mapped the deposition patterns of four essential mineral elements. Iron accumulated mainly in cells adjacent to vascular bundles, zinc localized preferentially within specific bundle regions, calcium concentrated in cells surrounding vascular tissues, and potassium was distributed broadly across most node cells. These element-specific patterns indicate that nodes selectively regulate mineral allocation rather than serving as passive conduits. Notably, rhizome nodes exhibited specialized vascular connections to crown roots and emerging shoot buds, supporting underground nutrient exchange. Together, the results demonstrate that bamboo nodes integrate structural specialization with mineral partitioning to meet diverse developmental and physiological demands.

“This work changes how we think about plant nutrient transport,” said the study's corresponding author. “Our results show that nodes are not just mechanical joints but active control centers that coordinate mineral allocation according to developmental needs.” The findings suggest that plants rely on finely tuned internal architectures to overcome limitations imposed by low transpiration or underground growth. By highlighting the functional importance of node-specific vascular organization, the study opens new avenues for understanding nutrient efficiency and adaptability in fast-growing plant species.

Identifying nodes as key hubs for mineral distribution has important implications for plant biology, agriculture, and forestry. A better understanding of node-mediated nutrient allocation could inform strategies to improve nutrient use efficiency in crops, particularly in species with complex growth forms or rapid biomass accumulation. For bamboo, an economically and ecologically valuable resource, insights into nutrient transport may support optimized cultivation, improved biomass quality, and stress resilience. More broadly, the findings provide a conceptual framework for exploring how structural specialization within plants supports adaptive nutrient management, offering potential targets for breeding or biotechnological interventions aimed at enhancing plant productivity.

###

References

DOI

10.1093/hr/uhaf113

Original Source URL

https://doi.org/10.1093/hr/uhaf113

Funding information

This work was financially supported by the National Natural Science Foundation of China (grant no. 31972495), the Zhejiang Provincial Natural Science Foundation of China (grant no. LQ20C160005), and the Agricultural Science and Technology Cooperation and Innovation Project of Hangzhou (202209SX13).

About Horticulture Research

Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.