Abstract
Relationships between gibberellins and floral initiation were investigated in a conditional non-flowering mutant of red clover, Trifolium pratense. Untreated mutant plants will not flower under long-days, but will do so when certain GAs are applied. Gibberellins, A3, A1, A7, and A5 all resulted in both stem elongation and flowering whilst GA4 produced the elongation only. Applications of GA20, GA8 and GA13 under long-days had no detectable effect. Thus, by combining the use of the mutant with the application of different GAs, the correlation between the processes of stem elongation and floral initiation, which is normally strongly expressed in this species, was broken. Endogenous gibberellins shown to be present in normal plants were also found in the mutant genotype. Gibberellins alone were not sufficient to initiate floral development in the mutant, there being an essential element of interaction with long-days. These results are discussed in relation to the nature of the lesion in the mutant and the signal provided by the applied gibberellin.
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Jones, T.W.A., Thomas, A.M. Flowering and gibberellins in a mutant red clover (Trifolium pratense L.). Plant Growth Regul 12, 11–16 (1993). https://doi.org/10.1007/BF00144576
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DOI: https://doi.org/10.1007/BF00144576