Ultrastructural studies on tendrils of plant climbers reveal a hierarchical tissue organization: A microscopic investigation

Tendrils are natural morphological designs that function as climbing adaptations adopted by weak-stemmed plants to attach over strong-stemmed supporting hosts or different artificial support systems. Tendrils are frequently either a modified stem, axillary bud or a modified leaf. Tendril recognises its ideal support hosts with its coiled spring onto which it finally attaches. Robotic engineers often quest for upgraded structures that can sense and grip. The present study focuses on comprehending the underlying structural features naturally present in plant tendrils. The study highlights three different types of plant tendrils. Evaluation of plant tendril morphometry is done by various high-performance structural analytical tools, notably Scanning Electron Microscopy, Atomic Force Microscopy and Fluorescence Microscopy. The ultrastructural features revealed the unique architectural design of cellulose fibrils and tissue-level organization in the anatomy, which enables the mechanical function of the tendrils. Additionally, the study supports that there are six different hierarchical chirality length scales. To improve and redesign machines, notably in robotics; to endow them with sensory perception, an analysis of the microscopic cellular structure of tendrils may be beneficial. The study also emphasizes that an extraordinary design with clear hierarchical patterns is required rather than replicating the shape.