In vitro culture of young floral buds of tomato (Lycopersicon esculentum mill.)

Young floral buds of tomato (Lycopersicon esculentum Mill.), with sepal primordia only, were cultured successfully in a liquid medium containing Murashige and Skoog's salts, White's vitamins and glycine, 3% (w/v) sucrose and benzylaminopurine (BAP). In 5 weeks, 60–70% of the cultured buds showed normal flower development through to anthesis, and a full complement of floral organs was produced. In the anthers, microsporogenesis occured and microspores and pollen grains were formed. The gynoecium was differentiated into an ovary, style and a stigma, and the ovary contained many ovules, some of which had developing embryo sacs. The floral organs grown in vitro were, however, smaller in size than those produced in vivo. In the control medium, i.e. without BAP, the floral buds produced petal and stamen primordia only and they too showed limited growth. The data presented shows the importance of cytokinins in the initiation and development of organs in the excised floral buds.