What is the correct sequence of steps during infection of plants by nitrogen-fixing bacteria?

A) Rhizobia release Nod factors; roots release flavonoids; rhizobia proliferate inside of root hair; infection thread grows into the root cortex; nodule forms.
B) Rhizobia release flavonoids; roots release Nod factors; rhizobia proliferate inside of root hair; infection thread grows into the root cortex; nodule forms.
C) Roots release flavonoids; rhizobia release Nod factors; rhizobia proliferate inside of root hair; nodule forms; infection thread grows into the root cortex.
D) Roots release flavonoids; rhizobia release Nod factors; rhizobia proliferate inside of root hair; infection thread grows into the root cortex; nodule forms.
E) Nodule forms; infection thread grows into the root cortex; rhizobia proliferate inside of root hair; rhizobia release flavonoids and Nod factors.


Answer: D

Biology & Microbiology

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