Leaf Discs as a Source Material for Plant Tissue Culture Studies of Sorghum bicolor (L.) Moench
Notulae Scientia Biologicae
Sorghum bicolor is one of the most difficult plant species to manipulate for tissue culture and genetic transformation; on the other hand Sorghum crop improvement through biotechnology requires efficient plant tissue culture protocols. In the present study a protocol has been optimized for Sorghum callus induction and regeneration from leaf tissue by optimizing the suitable explant, photoperiod and media composition. In Sorghum generally inflorescence tissue was used as explants for initiating
... allus cultures. Conversely, Sorghum flowering occurs only once in its life time and for few days only, thereby providing a small window of opportunity to provide source material or explant to initiate callus. Hence it is essential to identify a suitable explant, which can be available at any season. In the present study efficient callus induction was achieved on media supplemented in combination with 2 mgl-1 2,4,5-T plus 1 mgl-1 NAA and 0.5 mgl-1 ZN. Among the different combinations and concentrations of plant growth regulators tried for regeneration, 2.5 mgl-1 TDZ plus 1.0 mgl-1 BAP and 0.5 mgl-1 IAA showed better shoot regeneration frequency with 62.24.6 shoots per explant after 4 weeks of culture. Similarly, root induction was obtained from shoots with 1.0 mgl-1 NAA followed by their transfer to half strength MS medium which produced an average of two roots per shoot. Among the six genotypes tested, genotype IS3566 displayed superior results. Because of the reproducibility and the easy of accessibility of leaf tissue, the plant regeneration from leaf tissue provides a foundation for genetic transformation of Sorghum; this is of significant importance for improving important traits such as biomass, protein and sucrose content.