Induction of caulogenesis and somatic embryogenesis in
Cucumis melo (var. flexuosus).
Mohsen Hanana , Moncef Harrabi , Mohamed Boussaïd
Laboratoire de Génétique et Amélioration des Plantes, Institut National
Agronomique de Tunis (INAT), 43 Avenue Charles Nicolle, 1002 Tunis,
Tunisia.
Within the framework of genetic improvement of Tunisian Snake-melon
(Cucumis melo) cultivar by biotechnological methods, we have developed
a method to regenerate whole plants by in vitro culture using cotyledon
and hypocotyl as explants on MS medium with different combinations and
concentrations of auxin and cytokinin. Adventitious buds were initiated
from hypocotyls grown on medium with 1.5 mg 2,4-D/litre and 0.5 mg
benzyladenine/litre. A maximum percentage of embryogenesis (20%) was
obtained for cotyledons grown in MS medium containing 0.5 mg
2,4-D/litre and 1 mg kinetin/litre. For stimulating the development of
adventitious buds and the embryo's germination and their conversion
into plants, MS medium diluted twenty times and supplemented with 1.5%
sucrose was used. Histological studies showed that adventitious buds
were initiated from the peripheral zones of the organogenic calluses by
aggregation of meristematic cell masses which organized into a typical
shoot meristem. Embryoids resulted from the division of cells with a
dense cytoplasm, a large nuclei and a thick wall which are
differentiated on the callus periphery. |
