Figure 14.4 Fluorescence photomicrograph of a nat microbial community colonizing plant roots in soilN microcolony development.The preparation has been stai with acridine orange. Figure 14.7 Visualization of bacterial microcolonies (bacte. rial cells appear as greenish-yellow dots)on the surface of soil particles by use of the fluorescent antibody technique Cells are about 1 pm in diameter