Effect of growth regulators on in vitro morphogenic response of tomato

Abstract

A series of experiments were conducted to explore the in vitro morphogenic response of tomato genotypes viz., Castle Rock, Punjab Upma, VFN-8 and IPA-3, under different concentrations and combinations of growth regulators. The analysis of variance at 5% level of significance indicated that the differences among different genotypes, hormonal regimes as well as their interactions were statistically significant. The MS medium supplemented with BAP @ 3.0 mg L⁻¹ and IAA 2.5 mg L⁻¹ was optimum for callus induction, plant regeneration and number of shoots per explant. The maximum per cent callus induction and plant regeneration in the genotypes Castle Rock, Punjab Upma, VFN-8 and IPA-3. was 81.23, 76.69, 68.13 and 65.12%; and 46.91, 48.02, 57.14 and 60.23%, respectively, The respective average number of shoots per culture were 7.03, 6.92, 8.19 and 9.19. At higher and lower levels of hormones, a considerable decline was recorded in per cent callus induction, plant regeneration and number of shoots per explant. The best rooting was found to be in the ½ MS medium supplemented with 0.2 mg L⁻¹ IBA. Among the four soil mixtures studied viz., vermiculite, perlite, coco-peat and mixture of three (vermiculite, perlite and cocopeat in the ratio of 1:1:1), maximum plantlet survival rate was recorded in the mixture of three for genotypes Castle Rock and Punjab Upma and in vermiculite for genotype VFN-8.