Tissue Culture of Tobacco. II. Influence Of IAA, Kinetin and Sucrose on Organogenesis in Nicotiana Tabacum Callus Cultures

Summary Factors influencing the differentiation of shoot and root from floral bud callus of Nicotians tabecum were investigated. With low level of IAA (0.3 mg/l) in the Murashige and Skoog medium the differentiation of either shoot or root is brought about by altering the sucrose level in the medium. Sucrose at 2 and 3% induced caulogenesis, whereas at 6% in the same medium it facilitated rhizogenesis, Higher levels of IAA (0.5 and 2.0 mg/l) in the presence of sucrose (2 to 6%) invariably induced rhizogenesis. IAA and kinetic taken in the ratio of 1:1 could either induce shoot and root or exclusively shoots. High IAA to kinetin ratio does not induce rhizogenesis. Likewise high kinetin to IAA ratio does not favour caulogenesis. Synthetic auxins-IBA, NAA and 2, 4-D, and kinetin proved ineffective in inducing organogenesis.