Wheat can absorb clay particles through root cracks, study finds

By AI, Created 2:15 PM UTC, May 25, 2026, /AGP/ – New research shows wheat can take up micrometer-sized montmorillonite clay particles through tiny cracks at lateral root junctions, then move them into stems and leaves. The finding could reshape plant-soil science and inform new nutrient-delivery strategies for agriculture.

Why it matters: - Wheat can absorb micrometer-sized clay minerals that were long assumed too large to enter plant roots. - The discovery points to a previously overlooked route for moving minerals and nutrients into crops. - The finding could inform fertilizer design, soil amendments and broader sustainable agriculture research.

What happened: - Researchers from the Chinese Academy of Sciences and Qingdao University studied how wheat (Triticum aestivum) interacts with montmorillonite, a common clay mineral. - The study, published in Pedosphere in March 2025, tracked fluorescently labeled montmorillonite particles in hydroponic and soil-based systems. - The particles entered through cracks at sites where lateral roots emerged. - Once inside, the particles moved through the plant’s vascular system into stems and leaves. - The original article is available here.

The details: - The team used a stable fluorescent dye to tag montmorillonite and follow its movement over time. - Fluorescence appeared in root vascular tissues after 24 hours and intensified as exposure continued. - Confocal microscopy and scanning electron microscopy confirmed particle entry at lateral root junctions. - Tests in quartz sand and soil also showed uptake, though at lower levels because negatively charged soil particles interfered with movement. - SEM-EDS and high-resolution transmission electron microscopy detected montmorillonite in stems and leaves. - The transported particles carried potassium, calcium and iron. - The particles were coated in biomolecular coronas made of proteins, lipids and carbohydrates. - AFM-IR spectroscopy identified chemical signatures of those coronas and distinguished montmorillonite from silica-based particles. - The study identifies xylem transport as the route that carried the particles through the plant. - The research was supported by the National Natural Science Foundation of China and the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation.

Between the lines: - The result challenges the assumption that plant root barriers, including the Casparian strip, block clay particles entirely. - Natural fissures at lateral root junctions appear to create a backdoor for foreign particles. - Biomolecular coronas may affect how minerals move inside plants and how available those nutrients remain. - The finding raises the possibility that wheat and rice could directly use clay particles as alternative nutrient sources in depleted soils. - Dr. Yongming Luo said the study reveals a hidden route for nutrient delivery and creates a foundation for future work on soil-plant dynamics and nutrient management.

What’s next: - Future research is likely to test how broadly this uptake pathway applies across crops and soil types. - Scientists will also need to measure whether clay-based uptake can be turned into practical nutrient-delivery systems. - The findings could guide new nano-enabled fertilizers or soil amendments that mimic natural mineral uptake. - Further work will need to clarify how the biomolecular coronas influence plant metabolism and particle mobility.