Application of BAP and IAA for in vitro Callus Formation of Rose (Rosa indica cv. Ganganagri Gulab)

Abstract

A callus is a mass of undifferentiated cells capable of producing secondary metabolites. In this study, callus induction in Rosa spp. was evaluated using different concentrations of 6-Benzylaminopurine (BAP) and Indole-3-acetic acid (IAA) across the first, second, and third nodal segments under in vitro conditions. Callus formation was consistently observed in all tested combinations, with response rates ranging from 60% to 90% within 18.6 to 29 days of incubation. The highest callus induction was recorded in the third nodal segment, where a combination of 2.0 mg/L BAP + 2.0 mg/L IAA resulted in an 85% response rate and 0.93 g of callus weight in 18.6 days. A similar trend was noted in the second nodal segment, where 1.5 mg/L BAP + 1.5 mg/L IAA produced a 90% response rate and 0.93 g of callus weight in 20.6 days. The results indicated that equal concentrations of BAP and IAA yielded the highest callus induction across all nodal segments, with progressively increasing response rates and callus biomass from the first to the third nodal segment. Lower concentrations of IAA (0.5 mg/L) resulted in reduced callus formation, whereas higher concentrations (2.0 mg/L IAA) enhanced both the frequency of response and callus biomass.