Question

The correct sequence of events related to nodule formation of legumes is

A. Formation of bacteroids

B. Growth of infection thread

C. Secretion of sugars, amino acids and flavonoids by roots

D. Chemotactic movement of Rhizobia towards legume roots

• A. DCBA
• B. CDBA
• C. ABCD
• D. CDAB

Answer 1

The correct option is B

CDBA

Root hairs of legume secretes chemicals like sugars, amino acids and flavonoids. Rhizobia get attracted towards root hair and infects and proven infection thread. Rhizobia transform into active bacteroids in the nodule inner cortical cells and pericycle cells form nodule.