Influence of basal vitamins, growth regulators, and explants on in vitro organogenesis from synthetic seeds of Citrus jambhiri Lush.

Abstract

An efficient shoot and root organogenesis protocol has been developed from synseeds derived from various explants of Citrus jambhiri Lush. Optimum synseeds were developed using sodium alginate (0.5-0.75%) in 1.0% CaCl2 solution. Shoot organogenesis was examined under various basal vitamin mediums (MS Nitsch and MSB5) supplemented with various concentrations of adenine sulfate (ADS) and 6-benzyl amino purine (BAP) from different explants such as cotyledonary junction, shoot tip, and nodal explants. The synseed regeneration response ranged between 60-100% among the vitamins, cytokinins and explants used. The number of shoots per synseeds was higher (13.4) in MSB5-BAP (1.5 mg L-1), followed by 12.8 in MSN-ADS (2.0 mg L-1), 11.2 in MSN-ADS (1.0 mg L-1), and 10.8 in MSB5-ADS (1.0 mg L-1) from the synseeds developed using 0.75% sodium alginate. The mean number of roots per explant was higher (4.2) in ½MSN+IAA (1.0 mg L-1). Similarly, the mean root length was higher (5.2 cm) in ½MSN+IAA (0.5 mg L-1) followed by 4.2 cm in ½MSN+IAA (1.0 mg L-1). Regenerants derived from synseeds have shown no somaclonal variations, confirming that the plantlets are true-to-type to their parental progenies. The encapsulated plantlets showed >90% survivability while transferred at Kachai village, Manipur, India. The results of the present study encourage the use of various vitamin mediums and explants for large-scale propagation of C. jambhiri through synseeds.