Somatic embryogenesis and plant regeneration from suspension cultures of Sapindus trifoliatus

A procedure for plant regeneration from cell suspension cultures through somatic embryogenesis is described for Sapindus trifoliatus, a commercially and medicinally important tree. Callus was induced from leaf disc on agar-solidified MS medium with 5.0 mg l?1 2, 4-D and 0.01 mg l?1 Kin. Embryogenic cell suspension cultures were established by placing leaf-derived friable calli in PGR-free full-strength MS liquid medium with 3 percent sucrose. The growth of cell suspension culture was significantly affected by the strength of the MS mineral solution and L-glutamine. Plating of the suspension on semisolid MS medium resulted in the formation of globular structures. These embryogenic globular structures differentiated into secondary globular structures or somatic embryos on a semisolid MS medium. The differentiation of globular structures and different stages of somatic embryos (from globular to cotyledonary)was enhanced by the addition of 200 mg l?1 L-glutamine in the medium. Sucrose at relatively high concentrations (5 percent)or ABA (0.01 mg l?1)promoted somatic embryo maturation. The highest percentage (about 90 percent)of germination of somatic embryo and plantlet conversion was achieved on a half-strength MS medium containing 2 percent sucrose. The plants were hardened and established in soil with a 90 percent survival rate