Effect of cytokinins and exogenous amino acids on in vitro plant regeneration and Agrobacterium mediated genetic transformation of Chickpea (Cicer Arietinum L.)

In vitro regeneration of healthy shoots after Agrobacterium mediated genetic transformation of explants is an important step in development of transgenic plants. Here, we report the response of cytokinins and exogenous amino acids (L-cysteine, L-arginine & L-glutamine) in axillary meristem explants (AMEs) of chickpea cv. DCP 92-3, after cocultivaton with Agrobacterium tumefaciens. We employed previously standardized regeneration system of chickpea that utilizes a cytokinin, benzyl amino purine (BAP) for induction of multiple shoots (10.4 ± 1.66) from AMEs. Co-cultivated explants were subjected to different amino acids concentration to calculate regeneration response. Modified MS medium with L-cysteine, L-arginine and L-glutamine synergistically helped to recover high regeneration response percent by decreasing browning of explants. After 72 h, maximum responded explants (79%) were recorded on MS medium containing MS salts, B₅ vit., 1.0 mgl⁻¹ BAP, 200 mgl⁻¹ L-cysteine, 0.60 mgl⁻¹ L-glutamine and 0.70 mgl⁻¹ L-arginine, 3% sucrose, 0.8% agar, pH5.8. This modified medium can be effectively utilized for higher transformation frequency in chickpea.