A useful reference re: questions like this is "Nicotiana Procedures for
experimental use" USDA technical Bulletin Number 1586 R.D Durbin, ed.
1979 124 pp. Table 4.1 of this bulletin is relative to photoperiod. I
note that the commonly used mammoth type is SD. Jerry Cohen
On 11 Apr 1996, Diana Horvath wrote:
> Thanks to all who replied to my question about tobacco flowering
> conditions. The general answer is that most N. tabacum varieties
> are day neutral. Exceptions which are either LD or SD exist.
> Anyone interested in more detail and the references I received
> please e-mail.
>> Diana Horvath