Label-free multiphoton nonlinear microspectroscopy imaging of microbial cells and organic matter in rhizosphere and soil minerals

Abstract

We have developed a novel multiphoton nonlinear microscopy with a highly integrated optical imaging system that offers numerous label-free techniques including two-photon excited fluorescence, second-harmonic generation, third-harmonic generation, fluorescence lifetime imaging, and spectral focusing coherent anti-Stokes Raman scattering in one platform. We have applied our system to investigate plant-microbe-mineral interactions in the rhizosphere. The system provides time efficient monitoring of the rhizosphere, offering an array of simultaneous biomolecular information without staining, three-dimensional sub-micron resolution with deeper penetration , and less photodamage. We believe that multiphoton nonlinear optical microscopy will become a valuable imaging tool in the rhizosphere and soil mineral sciences.