THE EFFECT OF PLANT GROWTH REGULATORS ON CALLUS INDUCTION AND SOMATIC EMBRYOGENESIS OF HYBRID TOMATO

Efficient tissue culture system is important for transformation of important genes in hybrid tomato cultivars. The present study was undertaken to develop an efficient tissue culture system for hybrid tomato cultivar Peto-86. The young primary leaves and stems were inoculated into five different MS media having different concentrations of plant growth regulators in different combinations for callus induction, somatic embryogenesis and for both direct and indirect regeneration. Maximum callus induction frequency 90% was achieved with MS media containing 2,4-D 4 mg L-1 and BAP 0.5 mg L-1. The direct somatic embryogenesis was found highest on MS media supplemented with 2,4-D 4 mg L-1 and BAP 0.5 mg L-1. Maximum indirect regeneration frequency 87% was achieved from primary leaves explants with MS media containing IAA 0.5 mg L-1 and BAP 3 mg L-1 and highest direct regeneration frequency 77% was obtained from primary leaves explants with MS media containing NAA 1 mg L-1 and BAP 3 mg L-1. The high concentration of 2,4-D increased callus induction and somatic embryogenesis frequencies while the high concentration of BAP increased regeneration frequency. An improved tissue culture system of hybrid tomato cultivar Peto-86 was established and it may be recommended for further transformation experiments.