DEVELOPMENT OF SHOOTS AND ROOTS IN ANTHER-DERIVED CALLUS OF AZADIRACHTA-INDICA-A JUSS - A MEDICINAL TREE

Callus originated in microsporangial wall layers and connective tissues of anthers containing uninucleate microspores on Nitsch's or Murashige and Skoog's medium supplemented with growth regulators. A higher percentage of cultures (43) produced callus on Nitsch's medium containing 10 muM indole-3-acetic acid + 1 muM 6-benzyladenine. After 13-15 weeks, green nodular structures and prominent roots developed in 25% of the cultures on Murashige and Skoog's medium + 10 muM alpha-naphthaleneacetic acid + 1 muM kinetin. Multiple shoots were induced in this anther-derived callus when subcultured on Murashige and Skoog's medium augmented with 4.44 muM 6-benzyladenine + 0.53 muM a-naphthaleneacetic acid along with 18.75 muM polyvinylpyrrolidone. The excised shoots formed roots after subculturing on Murashige and Skoog's medium + 4.90 muM indole-3-butyric acid + 18.75 muM, polyvinylpyffolidone, thus developing complete plantlets. Examination of callusing anthers also revealed two- to multi-celled pollen masses with intact exine.