Abstract

ZEATIN INDUCED DIRECT PLANT REGENERATION FROM COTYLEDON EXPLANTS OF CULTIVATED TOMATO (LYCOPERSICON ESCULENTUM MILL.)

Byale Gundamma Kalyani and Srinath Rao*

ABSTRACT

An efficient protocol for multiple shoots induction and plant regeneration from cotyledon explants of cultivated tomato (Lycopersicum esculentum Mill.) cv Samrat-18 is reported. The cotyledon explants excised from of 10-12 days old in vitro grown seedlings were cultured on MS medium supplemented with 0.50- 1.2 mg/L Zeatin as a sole growth regulator and also in combination with 0.1/0.5 mg/L IAA. Maximum number of multiple shoots formation was found at 1.0 mg/L Zeatin with 0.1 mg/L IAA. Shoots were transferred to MS medium supplemented with 0.2-1.0 mg/L GA3 for elongation. The medium supplemented with 0.6 mg/L GA3 in showed the maximum percentage of enhancement of shoot elongation. For In vitro rooting, elongated shoots were excised and transferred onto MS medium supplemented with 0.5mg / L IBA, IAA and NAA. Profuse rhizogenesis was observed at 0.5 mg/L IBA compared to IAA / NAA. The regenerated plants were acclimatized in the culture room and maintained in the green house. These plants were found to be normal and similar to the donor plant. Thus, an efficient and reproducible direct regeneration protocol has been developed in cultivated tomato cv Samrat-18 using cotyledon explants which is genotype dependent.

Keywords: Acclimatization; Cotyledon explants; Plant regeneration; Zeatin.