Indian Journal of Horticulture

Investigation was conducted to develop a rapid in vitro regeneration protocol for Citrus jambhiri and C. karna, two important rootstocks commonly used in India. Among different plant growth regulators, the treatment containing 1 mg/l BAP, 0.5 mg/l NAA and 40 mg/l adenine sulphate significantly improved culture responses including percentage shoot bud formation, days required for shoot initiation, shoot length and number of resultant shoots per explant. Rooting was achieved on ½MS basal medium supplemented with NAA and IBA either in combination or individually at different concentrations. Medium containing 0.5 mg/l IBA + 0.5 mg/l NAA gave maximum response in both. The hardening medium consisted of 2 coco-peat: 1 solrite in which the survival rates of hardened plants were 94.7% in C. jambhiri and 96.7% in C. karna after one month. Subsequently, 65.5 and 71.8% in C. jambhiri and C. karna respectively, survived ex vitro.