Gram-negative nitrogen-fixing bacteria found in association with plant roots are
A) alphaproteobacteria.
B) betaproteobacteria.
C) cyanobacteria.
D) gammaproteobacteria.
E) deeply branching bacteria.

Question

Quizplus · Accepted Answer

Alphaproteobacteria include many species that are capable of nitrogen fixation and are often found in association with plant roots, such as the Rhizobium and Bradyrhizobium genera.

Gram-Negative Nitrogen-Fixing Bacteria Found in Association with Plant Roots Are