A Concise Compilation of the Diverse Detection Methods to Study Plant-Microbe Interfaces at the Cellular and Molecular Level: The Past, Present and Future

Abstract

Plant-microbe interaction can be classified under certain distinctive categories like synergistic, associative or pathogenic. The degree of friendly or hostile consortium depends on the kinds and species of microorganisms involved. These interactions are observed at various physiological planes of the host plant which in turn build the basis of molecular and genetic modifications. These changes then direct the path for biochemical reactions which occur between the plants and microbes. As a result of which, nutrient sequestration, mineral solubilization, nitrogen fixation, etc. are embarked upon by the plants, and in exchange the microbes get building blocks for energy conservation in their system. Due to this coevolutionary existence in the same niche, both have acquired mechanisms to defend each other’s non-complementary company as well. Before the scientific advent of modern molecular instruments and technologies, traditional methods such as culturing on solid media, light and electron microscopic observations and biochemical tests provided initial insight into a broader realization of how these two beings communicate. As years passed, the dire need of new, effortless techniques with contemporary serological and molecular-based methodologies like isozyme assays, polymerase chain reaction (PCR), enzyme-linked assays (ELISA, RIA), microarrays (lab-on-chip), nucleic acid-based techniques (next-generation sequencing, whole genome sequencing, etc.) surfaced. Also, the invention of particular high-resolution microscopic techniques like video microscopy, confocal laser scanning microscopy (CLSM) and fluorescence microscopy brought a whole set of new information at cellular level. Apart from these, high spectral imaging also proved to be efficient enough to detect the disease symptoms at an early stage based on volatile organic compound profiling. A compilation is presented.