A temperature-dependent morphological mutant of tobacco.

A recessive temperature dependent shooty mutant (tds) of Nicotiana tabacum L. (W38) is described. The mutant phenotype is expressed at low temperature (21 degrees C). Mutant characteristics include thick, narrow leaves with abnormal mesophyll cells, short internodes, and near absence of apical dominance. Most plants remain vegetative and the occasional flower has petaloid stamens. High temperature (30 degrees C) reverses the mutant phenotype, with formation of normal leaves and restoration of apical dominance. However, many flowers still have petaloid stamens. Reciprocal grafting and auxincytokinin interaction experiments do not suggest shifts in auxin-cytokinin balance. Overall, this mutant bears some resemblance to transgenic tobacco overexpressing homeodomain genes from maize and Arabidopsis.