Regeneration and histological analysis of snake melon (Cucumis melo var. flexuosus (L.) Naudin) by direct organogenesis

In vitro morphogenesis of Cucumis melo var. flexuosus (L.) Naudin was studied by direct organogenesis. Induction of adventitious buds was obtained from distal and proximal parts of the cotyledon incubated on Murashige and Skoog (1962) medium containing different concentrations of 6-benzyladenine (BA) (0.0, 0.5, 1.0, and 2.0 mg L^-1) and indole-3-acetic acid (IAA) (0.0, 0.1, and 0.5 mg L^-1). The best organogenesis was obtained from the proximal part of the cotyledon on medium containing 0.5 mg L^-1 BA and 0.5 mg L^-1 IAA (88%). This concentration was used for histological analysis. Less regeneration was obtained on media containing 1.0 mg L^-1 BA (75%) or 1.0 mg L^-1 BA and 0.1 mg L^-1 IAA (60%). Plant recovery was much greater from proximal rather than distal explants. A callus formed on almost every explant on media supplemented with BA. Histological analyses showed that the formation of early shoot apical meristems was observed in 14-day-old tissues and meristematic structures were seen in 17-day-old tissues. The first shoot was formed after 21 days. By this time, the surface was covered with leaf primordia and leaves, mostly without accompanying buds.