Conditions for Strict Autotrophic Culture of Tobacco Callus

Conditions for strict autotrophic culture of tobacco callus.

Organic gelling agents such as agar and agarose provide a heterotrophic substrate for growth of illuminated tobacco callus. When green cells are incubated in CO(2)-free air on a medium lacking sucrose but solidified with 1% agar, an increase in relative dry weight is sustained through two passages. Similar results with different inoculum sources, and with three brands of agar and two forms of a...

Effects of CO(2) and O(2) on Photosynthesis and Growth of Autotrophic Tobacco Callus.

Mean inhibition of net photosynthesis in autotrophic tobacco callus by 21 and 40% O(2) was 30 and 47%, respectively, similar to intact leaves. Increasing CO(2) concentrations (500-2000 microliters per liter) produced a steady decline in percent inhibition at both O(2) concentrations, indicating that O(2) inhibition resulted primarily from photorespiration. Net photosynthetic rate was plotted as...

Callus culture and regeneration.

Epigenetic switches of tobacco transgenes associate with transient redistribution of histone marks in callus culture

In plants, silencing is usually accompanied by DNA methylation and heterochromatic histone marks. We studied these epigenetic modifications in different epialleles of 35S promoter (P35S)-driven tobacco transgenes. In locus 1, the T-DNA was organized as an inverted repeat, and the residing neomycin phosphotransferase II reporter gene (P35S-nptII) was silenced at the posttranscriptional (PTGS) le...

Application of ZnO Nanoparticles for Inducing Callus in Tissue Culture of Rapeseed

   Present study has comparatively investigated the effect of zinc oxide nanoparticles (ZnO NPs), ZnO bulk particles (BPs), and relevant metal ions (Zn2+) on the tissue culture of rapeseed (Brassica napus L.) to properly evaluate the impact of ZnO NPs on callus induction. For finding the best hormonal combination for inducing callus, hypocotyl explants were cultured on Murashige ...