Abstract
Interspecific crosses involving the yellow-flowered Camellia chrysantha (diploid) have proved unsuccessful in the establishment of hybrid plants. In our hybridization program, five controlled pollinations between C.vietnamensis (hexaploid) and C. chrysantha successfully produced two mature capsules which contained three viable seeds. Mature cotyledons of these viable seeds cultured in vitro proliferated slowly for approximately six months on Murashige and Skoog (MS) medium containing 3.0mg/l benzyl-adenine and 1.0mg/l α naphthalene acetic acid. After they were transplanted on MS medium supplemented with 10% coconut milk and 1mg/l gibberelin(GA3), the whole surface of the cotyledons formed numerous yellowish or greenish organs. Only 4.3% (6/138) of the generated buds formed shoots longer than 5cm with leaf development and grew up to plantlets. Karyomorphological characteristics in root meristematic cells indicated that these new plants (tetraploid) were true hybrid individuals between C.vietnalnensis and C.chrysantha.
