Tobacco plants exhibit strong apical dominance because molecular signals from the shoot apical meristem (SAM) mediate hormonal regulation effectively inhibiting axillary bud growth. Upon SAM removal, however, hormonal signals are lost enabling axillary buds to grow into new shoots (or “suckers”). In traditional tobacco production practices, manual removal or chemicals are used for sucker management. Chemical use not only increases leaf production costs but can also leave undesired residues on cured leaf. Therefore, development of tobacco varieties with reduced or inhibited sucker pressure would have a positive impact on tobacco production.

Expression of a cell death gene under control of axillary bud specific promoters resulted in reduction of sucker growth. However, due to promoter leakage, next generation viable seed was not obtained. To achieve viable seed production, promoter analyses were conducted. Upon promoter modification and improvement, sucker control plants produced viable seed and the phenotype was successfully passed to the next generation. In this presentation, we will discuss promoter modifications and T1 plant performance in both greenhouse and field.