Atomic force microscopy (AFM) provides a powerful tool for quantifying the nanoscale mechanics of biological systems, linking molecular- and microfibril-level properties to organismal growth and agricultural performance. Here, we applied AFM-based force spectroscopy to investigate the structural and mechanical basis of plant cell wall function in both a model plant ( Arabidopsis thaliana ) and cotton species ( Gossypium hirsutum Gh and Gossypium barbadense Gb). We correlated the ixr1-2 mutant, which is resistant to isoxaben , with wild-type hypocotyls in Arabidopsis . Cellulose microfibrils in the wild type were better oriented, stiffer, and less deformable than those in ixr1-2 , which showed disordered organization and decreased mechanical integrity. These macroscopic variations in hypocotyl elongation are reflected by these nanoscale variations, which were detected by Young’s modulus, deformation, and roughness studies. This illustrated how force spectroscopy can contribute to molecular-scale alterations to growth outcomes. Extending this framework to cotton, a popular crop, we characterized microfibrils of Gb and Gh during four developmental growth stages (8, 12, 18, and 22 days post-anthesis). Gb's smoother texture and higher fiber quality can be explained by its consistent display of stronger, finer, and better-organized microfibrils. Furthermore, machine-learning algorithms were also able to predict agricultural features, such as boll length and cellulose content, with R 2 accuracies of 0.66 and 0.82, respectively, when transcriptome data and nanoscale spectroscopic data were combined. Collectively, these investigations demonstrated that AFM force spectroscopy serves as a translational platform for agriculture and a potential tool for examining the nanoscale mechanics of plant cell walls. This method opens a path for mechanobiology-informed crop improvement by linking nanomechanical properties information to macroscopic performance and predictive breeding techniques.
Masud et al. (Sun,) studied this question.