A taproot root consists of one large main root with smaller roots that branches off into the soil, while the fibrous roots consists of several main roots that branches off to form one mass of roots.
The root system in plants helps them to absorb water and other nutrients from the soil.
A taproot is much more like extension of stem that penetrates into the ground.
It tapers at the end with many other smaller roots branching and networking from it.
The fibrous root is a series of roots directly from the stem that independent of one another.
Roots are used by plants for anchorage into the soil.
Those would be called indicators , simply google them and you should find many. I'll leave some examples "bromophenol blue" "Methyl red" and "phenol red".
