Cytokinin application to reduce TSNAs in burley tobacco

The goal of this study is to test whether spraying burley tobacco with the synthetic cytokinin benzyladenine is an efficient, cost-effective method for lowering TSNAs. Cytokinins increase nitrogen utilization and the antioxidative capacity of the plant, and can delay senescence. We hypothesize that short cytokinin treatments alter the nitrogen metabolism and cellular antioxidative capacity, possibly lowering TSNA accumulation. Results from a pilot study were promising: we found that the cytokinin application indeed lowered TSNA levels. We also found that the cytokinin concentration used does not delay senescence but instead promotes the senescence process, a potentially beneficial effect for the curing of tobacco leaves. This suggests that higher cytokinin concentrations could be used without causing any senescence delays. Now that we have proof of concept, we are planning tests to establish the most suitable application. This year, we propose to increase the cytokinin concentration to test whether this causes an even stronger suppression of TSNA formation without adversely affecting curing. Signature: