SOMATIC EMBRYOGENESIS FROM IMMATURE COTYLEDONS AND LEAF CALLI OF CHICKPEA (CICER ARIETINUM L.)

Somatic embryogenesis was induced in both direct and indirect pathways from immature cotyledons and young leaf explants of chickpea (Cicer arietinum) on MS medium with various concentrations of auxins and cytokinins. NAA and 2,4-D were used in the range of 1.0-16.0 mg/l. NAA 10-14 mg/l induced direct embryo formation on cut edges of immature cotyledons on adaxial surface. These pro-embryonic structures enlarged into distinct globular pro-embryoids within 4 weeks of incubation. Further growth of these pro-embryoids was limited and very few of these exhibited either shoot or root polarity. Auxins: cytokinins combinations also promoted induction of indirect embryogenesis. The best response was noticed in the medium 3 mg/l 2,4-D + 0.1 mg/l BAP. After 10-15 days leaf explants induced nodular callus consisted of pro-embryoids. After 5-6 weeks, the pro-embryoids transformed into embryo development phase ranging from globular, heart to torpedo stages. The sustainability and further growth of somatic embryos was investigated by shifting both direct and indirect embryoids on basal media. The frequency of embryogenesis and subsequent plantlet regeneration was found higher in indirect embryogenesis as compared to direct embryo formation