THE PRESENT INVESTIGATION WAS UNDERTAKEN TO STUDY THE EFFECT OF DIFFERENT CONCENTRATIONS AND COMBINATIONS OF 2, 4-DICHLORO-PHENOXYACETIC ACID (2, 4-D), NAPHTHALENE ACETIC ACID (NAA) ON CALLUS INDUCTION OF FIVE CITRUS ROOTSTOCKS (SOUR ORANGE, CITROMELO, CITRANGE, PONCIRUS, VOLKAMERIANA) ON MS BASAL MEDIUM. DIFFERENT CONCENTRATION OF 2, 4-D AND NAA WERE TASTED IN ORDER TO OBTAIN THE BEST CALLUS FORMATION. MAXIMUM CALLUS INDUCTION RESPONSE (100%) WAS OBTAINED ON MS MEDIUM WITH 2, 4-D (2 AND 3MG/L) AND NAA (1.5 MG/L) FOR VOLKAMERIANA. BEST CALLUS INDUCTION RESPONSE OF CITRANGE (83.33%) WAS OBSERVED ON MS MEDIUM WITH 2, 4-D (1 MG/L) AND NAA (1.5 MG/L). THE HIGHEST FREQUENCY OF THE CALLUS INDUCTION RATE FOR PONCIRUS AND CITROMELO (91.67%) WAS OCCURRED ON MS MEDIUM SUPPLEMENTED WITH 2.4-D (3 MG/L) AND NAA (1.5 MG/L). MS MEDIUM SUPPLEMENTED WITH 2, 4-D (1 MG/L) AND NAA (1.5 MG/L) SHOWED MAXIMUM CALLUS INDUCTION (91.76%) FOR SOUR ORANGE.