The Role of Plant Growth Regulators, Sucrose and pH in the Development of Floral Buds of Tomato ( Lycopersicon esculentum Mill.) Cultured in vitro

Abstract

The relative efficiency of different cytokinins i.e., BAP, kinetin, zeatin and zeatin riboside, and the role of NAA, GA 3 , sucrose and pH, on the in vitro growth and development of young floral buds of tomato ( Lycopersicon esculentum Mill.) was examined. Of the various cytokinins tested, BAP was the most and zeatin the least effective in terms of the number of floral buds attaining maturity. Naphthaleneacetic acid alone was without effect, as well, it antagonized the promotory effect of BAP on flower development. Gibberellic acid alone was also ineffective, but in combination with BAP — and depending upon the GA 3 concentration — it was either inhibitory, ineffective, or promotory for the growth of different floral organs. The optimal concentration of sucrose for the maturation of flowers was 3%, but the growth of floral organs was maximal at 4% sucrose level. Low pH (3.8–4.5) enhanced the growth of some floral parts, but the number of flowers reaching maturity was maximum at pH 5.8. This study shows that the in vitro growth and maturation of floral organs of tomato require different levels of various factors.