title: A new approach for in vitro regeneration of tomato plants devoid of exogenous plant growth hormones.
abstract: Many available methodologies for in vitro regeneration of commercial tomato varieties promote not only the production of normal shoots but also individual leaves, shoots without apical meristems and vitrified structures. All these abnormal formations influence and diminish the regeneration efficiency. At the basis of this phenomenon lies callus development. We optimized an alternative procedure by which the regeneration occurs without abnormal shoot formation. The portion including the proximal part of hypocotyls and the radicle was cultured on medium consisting of Murashige and Skoog salts, 4 mg/L thiamine, 100 mg/L mio-inositol and 3% sucrose. After two-three weeks, 60% explants showed adventitious shoot formation. No changes in the morphological characteristics of regenerated plants and fruits were observed as compared with parents. Karyotypic analysis of regenerated plants showed no variations in chromosome number. The optimized procedure offers the advantage of tomato plant regeneration avoiding callus formation, which enables normal plant recovery with an efficiency ranging from 1.45 +/- 0.05 to 2.57 +/- 0.06 shoots per explant in Campbell-28, Amalia, Lignon, and Floradel cultivars.
authors.affiliation: National Institute of Agricultural Sciences, San Joséde las Lajas, Havana, Cuba.
authors.forename: Dagmara
authors.initials: D
authors.lastname: Plana
authors.forename: Alejandro
authors.initials: A
authors.lastname: Fuentes
authors.forename: Marta
authors.initials: M
authors.lastname: Alvarez
authors.forename: Regla M
authors.initials: RM
authors.lastname: Lara
authors.forename: Félix
authors.initials: F
authors.lastname: Alvarez
authors.forename: Merardo
authors.initials: M
authors.lastname: Pujol
mesh_terms: D000383:Agriculture / Q000379:methods*; D018929:Cell Culture Techniques / Q000379:methods*; D002478:Cells, Cultured; D018551:Solanum lycopersicum / Q000502:physiology*; D038081:Organogenesis / Q000502:physiology*; D010937:Plant Growth Regulators / Q000494:pharmacology; D012038:Regeneration / Q000502:physiology*
chemical_list: D010937:Plant Growth Regulators