In vitro plant regeneration in rough lemon (Citrus jambhiri L.)

Abstract

The present study was conducted to optimize the protocol for plant regeneration from stem, leaf, and root explants of rough lemon (Citrus jambhiri L). Explants from in vitro grown seedling of C. jambhiri were cultured on MS medium supplemented with various concentration of α-Naphthaleneacetic acid (NAA), 2,4-Dichlorophenoxy acetic acid (2,4-D) and 6-Benzylaminopurine (BA) for callus and shoot initiation. MS medium fortified with various concentrations of NAA were used for root formation. The range of callus initiation from stem explants of C. jambhiri was 13.33% to 80%, whereas 13.33% to 56.66% from leaf explants showed; and 6.66% to 36.66%
from root explants. The frequency of shoot regeneration ranged from 13.33 to 70% from 15 days old callus. The highest frequency of callus initiation and shoot regeneration was observed in MS media supplemented with 1 mg L−1 2,4-D and 0.5 mg L−1 BA; and MS media supplemented with 0.5 mg L−1 NAA and 3 mg L−1 BA, respectively. Rooting frequency ranged from 6.66% to 96.66% in the regenerated shoots. The acclimatized plants transferred to field condition survived at 100% frequency. MS media supplemented with 1 mg L−1 2,4-D and 0.5 mg L−1 BA is the proper medium for high frequency (80%) callus induction in C. jambhiri using stem explant. MS media supplemented with 0.5 mg L−1 NAA and 3 mg L−1 BA and MS with 0.2 mg L−1 NAA are the best media for high frequency shoot regeneration (70%) and root initiation (96.66%), respectively.