Abstract:
:The temporal and spatial patterns of floral determination in cultured internode segments of Nicotiana tabacum L. cv. Wisconsin 38 were investigated. Segments from internodes, when cultured on hormone-free medium, either produced some de novo floral shoots or produced only vegetative shoots. Segments that produced some floral shoots were considered to contain florally determined tissues. The first internode tissues to exhibit floral determination were located 24 nodes (about 15 cm) below the terminal meristem on plants that had 21 leaves of length >/=3 cm (i.e., plants of age 21). Since the terminal meristem was morphologically vegetative at this age, floral determination in internode tissues did not result from a signal emanating from floral structures. As the plant continued growing, internode tissues progressively higher on the main axis gained the capacity to produce de novo floral shoots in culture. These data indicate that the inductive signal which elicited the state of floral determination in internode tissues was active in the upper half of the plant beginning at about age 21.
journal_name
Proc Natl Acad Sci U S Aauthors
Singer SR,McDaniel CNdoi
10.1073/pnas.84.9.2790subject
Has Abstractpub_date
1987-05-01 00:00:00pages
2790-2issue
9eissn
0027-8424issn
1091-6490journal_volume
84pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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